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Oracle
®
Real Application Clusters
Administration and Deployment Guide
12c Release 2 (12.2)
E49900-12
July 2017
Oracle Real Application Clusters Administration and Deployment Guide, 12c Release 2 (12.2)
E49900-12
Copyright
©
2009, 2017, Oracle and/or its affiliates. All rights reserved.
Primary Author: Richard Strohm
Contributing Authors: Janet Stern
Contributors: Troy Anthony, Lance Ashdown, Ram Avudaiappan, Prasad Bagal, Mark Bauer, Anand
Beldalker, Eric Belden, Gajanan Bhat, David Brower, George Claborn, Maria Colgan, Carol Colrain, Jonathan
Creighton, Rajesh Dasari, Steve Fogel, Richard Frank, GP Prabhaker Gongloor, Wei Hu, Yong Hu,
Dominique Jeunot, Sameer Joshi, Raj K. Kammend, Ankita Khandelwal, Sana Karam, Roland Knapp, Karen
Li, Barb Lundhild, Venkat Maddali, Bill Manry, John McHugh, Saar Maoz, Matthew Mckerley, Markus
Michalewicz, Anil Nair, Philip Newlan, Michael Nowak, Muthu Olagappan, Bharat Paliwal, Hanlin Qian,
Mark Ramacher, Sampath Ravindhran, Kevin Reardon, Kathy Rich, Dipak Saggi, Daniel Semler, Ara
Shakian, Cathy Shea, Khethavath P. Singh, Kesavan Srinivasan, Leo Tominna, Peter Wahl, Tak Wang,
Richard Wessman, Douglas Williams, Mike Zampiceni, Michael Zoll
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Contents
Preface
Changes in This Release for Oracle Real Application Clusters Administration and
Deployment Guide
1 Introduction to Oracle RAC
Oracle RAC Database Management Styles and Database Installation.....................................
Overview of Using Dynamic Database Services to Connect to Oracle Databases ...............
iii
Overview of Automatic Workload Management with Dynamic Database Services ...................
2 Administering Storage in Oracle RAC
Configuring Preferred Mirror Read Disks in Extended Distance Clusters .............................
Administering Oracle ASM Instances with SRVCTL in Oracle RAC.......................................
3 Administering Database Instances and Cluster Databases
Starting One or More Instances and Oracle RAC Databases Using SRVCTL .........................
Stopping One or More Instances and Oracle RAC Databases Using SRVCTL.......................
iv
Converting an Administrator-Managed Database to a Policy-Managed Database......................
Administering Multiple Cluster Interconnects on Linux and UNIX Platforms............................
Use Cases for Setting the CLUSTER_INTERCONNECTS Parameter ....................................
Using Oracle Enterprise Manager Cloud Control to Discover Nodes and Instances ..........
4 Administering Oracle RAC One Node
Converting a Database from Oracle RAC to Oracle RAC One Node.......................................
Converting a Database from Oracle RAC One Node to Oracle RAC.......................................
5 Workload Management with Dynamic Database Services
Configuring Your Environment to Use the Load Balancing Advisory ....................................
v
Enabling ODP.NET Clients to Receive FAN High Availability Events .................................
Enabling ODP.NET Clients to Receive FAN Load Balancing Advisory Events...................
Measuring Performance by Service Using the Automatic Workload Repository.........................
6 Ensuring Application Continuity
vi
7 Configuring Recovery Manager and Archiving
Oracle Automatic Storage Management and Cluster File System Archiving Scheme ..........
8 Managing Backup and Recovery
Using RMAN or Oracle Enterprise Manager to Restore the Server Parameter File
vii
9 Cloning Oracle RAC to Nodes in a New Cluster
10 Using Cloning to Extend Oracle RAC to Nodes in the Same Cluster
11 Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems
Adding Policy-Managed Oracle RAC Database Instances to Target Nodes.........................
Adding Administrator-Managed Oracle RAC Database Instances to Target Nodes ..........
12 Adding and Deleting Oracle RAC from Nodes on Windows Systems
Adding Administrator-Managed Oracle RAC Database Instances to Target Nodes ..........
13 Design and Deployment Techniques
Best Practices for Deploying Oracle RAC in a High Availability Environment ...................
Consolidating Multiple Applications in a Database or Multiple Databases in a Cluster....
viii
Node Addition and Deletion and the SYSAUX Tablespace in Oracle RAC..........................
14 Monitoring Performance
15 Converting Single-Instance Oracle Databases to Oracle RAC and Oracle
RAC One Node
Converting Oracle Database Installations to Oracle RAC Using DBCA................................
Converting Single Instance on a Cluster to Oracle RAC One Node Using DBCA...............
Converting Single Instance on a Cluster to Oracle RAC Using DBCA ..................................
Configuration Changes During Oracle RAC Conversion Using rconfig...............................
Converting Databases to Oracle RAC Using rconfig or Oracle Enterprise Manager.........
ix
x
Converting Databases to Oracle RAC Using Oracle Enterprise Manager...........................
A Server Control Utility Reference
B Troubleshooting Oracle RAC
Glossary
Index
xi
xii
List of Tables
How SQL*Plus Commands Affect Instances...........................................................................
3-6
Descriptions of V$ACTIVE_INSTANCES Columns ...........................................................
3-14
Initialization Parameters Specific to Oracle RAC ................................................................
3-19
Parameters That Should Have Identical Settings on All Instances....................................
3-23
Load Balancing Advisory FAN Events....................................................................................
5-7
Standard Tests for Some Common Application Servers.......................................................
6-6
Event Parameter Name-Value Pairs and Descriptions........................................................
6-14
FAN Parameters and Matching Session Information..........................................................
6-16
Example Treatment of Mutable Objects by Products During Replay...............................
6-37
Archived Redo Log File Name Format Parameters ..............................................................
7-5
UNIX/NFS Location Log Examples, Noncluster File System Local Archiving.................
7-9
UNIX/NFS Configuration for Shared Read Local Archiving Examples ...........................
7-9 clone.pl Script Parameters..........................................................................................................
9-4
Environment Variables Passed to the clone.pl Script.............................................................
9-5
Cloning Parameters Passed to the clone.pl Script..................................................................
9-5
Finding the Location of the Oracle Inventory Directory.......................................................
9-7
Variables in the DBCA Silent Mode Syntax..........................................................................
11-5
String Restrictions for SRVCTL Object Names.......................................................................
A-3
Deprecated Single-Character Parameters for SRVCTL Commands....................................
A-7
Deprecated Commands and Parameters for SRVCTL........................................................
A-16
Object Keywords and Abbreviations.....................................................................................
A-17 srvctl add database Command Parameters..........................................................................
A-18
srvctl config database Command Parameters......................................................................
A-21 srvctl convert database Command Parameters....................................................................
A-22 srvctl disable database Parameters.........................................................................................
A-23 srvctl disable diskgroup Parameters......................................................................................
A-24
srvctl add instance Command Parameters...........................................................................
A-25
srvctl disable instance Parameters..........................................................................................
A-26
srvctl add listener Command Parameters.............................................................................
A-27
srvctl disable listener Parameters...........................................................................................
A-29
srvctl config listener Command Parameters.........................................................................
A-29
srvctl add network Command Parameters...........................................................................
A-30
srvctl add nodeapps Command Parameters.........................................................................
A-32
srvctl disable nodeapps Parameters.......................................................................................
A-33
srvctl add ons Command Parameters....................................................................................
A-34
srvctl add scan Command Parameters..................................................................................
A-35
srvctl config scan Command Parameters..............................................................................
A-36
srvctl add scan_listener Command Parameters...................................................................
A-37
srvctl config scan_listener Command Parameters...............................................................
A-38
srvctl add service Command Parameters..............................................................................
A-40
srvctl config service Command Parameters..........................................................................
A-47
srvctl disable service Parameters............................................................................................
A-48
srvctl add srvpool Command Parameters.............................................................................
A-49
srvctl add vip Command Parameters....................................................................................
A-51
srvctl config vip Command Parameters................................................................................
A-52
srvctl disable vip Parameters..................................................................................................
A-52
srvctl config volume Command Parameters........................................................................
A-53
srvctl disable volume Parameters...........................................................................................
A-54
srvctl downgrade database Parameters.................................................................................
A-55
srvctl enable Summary.............................................................................................................
A-56
srvctl enable database Parameters..........................................................................................
A-56
xiii
xiv
srvctl enable diskgroup Parameters.......................................................................................
A-57
srvctl enable instance Parameters...........................................................................................
A-57
srvctl enable listener Parameters............................................................................................
A-58
srvctl enable nodeapps Parameters........................................................................................
A-59
srvctl enable service Parameters.............................................................................................
A-60
srvctl enable vip Parameters...................................................................................................
A-61
srvctl enable volume Parameters............................................................................................
A-62
srvctl getenv Summary............................................................................................................
A-63
srvctl getenv database Parameters.........................................................................................
A-63
srvctl getenv listener Parameters............................................................................................
A-63
srvctl getenv nodeapps Parameters.......................................................................................
A-64
srvctl getenv vip Parameters...................................................................................................
A-65
srvctl modify Summary...........................................................................................................
A-65
srvctl modify database Parameters........................................................................................
A-66
srvctl modify instance Command Parameters.....................................................................
A-70
srvctl modify listener Parameters...........................................................................................
A-71
srvctl modify network Parameters.........................................................................................
A-72
srvctl modify nodeapps Parameters......................................................................................
A-75
srvctl modify ons Parameters..................................................................................................
A-76
srvctl modify scan Command Parameters............................................................................
A-77
srvctl modify scan_listener Command Parameters.............................................................
A-78
srvctl modify service Parameters for Moving a Service......................................................
A-79
srvctl modify service Parameters for Changing to a Preferred Instance..........................
A-79
srvctl modify service Parameters for Changing Status of Multiple Instances.................
A-80
srvctl modify service Parameters............................................................................................
A-81
srvctl modify srvpool Parameters..........................................................................................
A-85
srvctl modify vip Parameters..................................................................................................
A-86
srvctl predict Summary............................................................................................................
A-87
srvctl predict database Parameters.........................................................................................
A-88
srvctl predict diskgroup Parameters......................................................................................
A-88
srvctl predict listener Parameters...........................................................................................
A-89
srvctl predict network Parameters.........................................................................................
A-89
srvctl predict scan Parameters................................................................................................
A-90
srvctl predict scan_listener Parameters.................................................................................
A-90
srvctl predict service Parameters............................................................................................
A-91
srvctl predict vip Parameters..................................................................................................
A-91
srvctl relocate Command Summary.......................................................................................
A-92
srvctl relocate database Parameters.......................................................................................
A-92
srvctl relocate scan Parameters...............................................................................................
A-94
srvctl relocate scan_listener Parameters................................................................................
A-94
srvctl relocate server Parameters............................................................................................
A-95
srvctl relocate service Command Parameters.......................................................................
A-95
srvctl relocate vip Parameters.................................................................................................
A-98
srvctl remove Summary...........................................................................................................
A-98
srvctl remove database Command Parameters....................................................................
A-99
srvctl remove diskgroup Parameters...................................................................................
A-100
srvctl remove instance Parameters.......................................................................................
A-101
srvctl remove listener Parameters........................................................................................
A-101
srvctl remove network Parameters......................................................................................
A-102
srvctl remove nodeapps Parameters....................................................................................
A-103
srvctl remove ons Parameters...............................................................................................
A-103
srvctl remove scan Command Parameters.........................................................................
A-104
srvctl remove scan_listener Command Parameters..........................................................
A-104
srvctl remove service Parameters.........................................................................................
A-105
srvctl remove srvpool Parameters........................................................................................
A-106
srvctl remove vip Parameters...............................................................................................
A-106
srvctl remove volume Parameters........................................................................................
A-107
srvctl setenv Summary...........................................................................................................
A-108
srvctl setenv database Parameters........................................................................................
A-108
srvctl setenv listener Parameters..........................................................................................
A-109
srvctl setenv nodeapps Parameters......................................................................................
A-109
srvctl setenv vip Parameters.................................................................................................
A-110
srvctl start Summary..............................................................................................................
A-111
srvctl start database Parameters...........................................................................................
A-111
srvctl start diskgroup Parameters........................................................................................
A-113
srvctl start home Parameters.................................................................................................
A-113
srvctl start instance Parameters............................................................................................
A-114
srvctl start listener Command Parameters..........................................................................
A-115
srvctl start nodeapps Parameters.........................................................................................
A-115
srvctl start scan Parameters...................................................................................................
A-116
srvctl start scan_listener Parameters....................................................................................
A-117
srvctl start vip Parameters.....................................................................................................
A-119
srvctl start volume Parameters.............................................................................................
A-120
srvctl status Summary............................................................................................................
A-121
srvctl status database Parameters.........................................................................................
A-121
srvctl status diskgroup Parameters......................................................................................
A-123
srvctl status home Parameters..............................................................................................
A-123
srvctl status instance Parameters..........................................................................................
A-124
srvctl status listener Parameters...........................................................................................
A-125
srvctl status scan Parameters................................................................................................
A-126
srvctl status scan_listener Parameters.................................................................................
A-126
srvctl status server Parameters.............................................................................................
A-127
srvctl status service Parameters............................................................................................
A-127
srvctl status srvpool Parameters...........................................................................................
A-128
srvctl status vip Parameters..................................................................................................
A-129
srvctl status volume Parameters...........................................................................................
A-129
srvctl stop Summary..............................................................................................................
A-131
srvctl stop database Command Parameters.......................................................................
A-132
srvctl stop diskgroup Parameters.........................................................................................
A-133
srvctl stop home Parameters.................................................................................................
A-133
srvctl stop instance Command Parameters.........................................................................
A-134
srvctl stop listener Command Parameters..........................................................................
A-135
srvctl stop nodeapps Parameters..........................................................................................
A-136
srvctl stop scan Parameters...................................................................................................
A-137
srvctl stop scan_listener Parameters....................................................................................
A-138
srvctl stop service Command Parameters...........................................................................
A-138
srvctl stop vip Parameters.....................................................................................................
A-140
srvctl stop volume Parameters.............................................................................................
A-141
srvctl unsetenv Command Summary..................................................................................
A-142
srvctl unsetenv database Parameters...................................................................................
A-142
srvctl unsetenv listener Parameters.....................................................................................
A-143
srvctl unsetenv nodeapps Parameters.................................................................................
A-143
srvctl unsetenv vip Parameters.............................................................................................
A-144
srvctl update Command Summary......................................................................................
A-144
srvctl update gns Parameters................................................................................................
A-146
srvctl upgrade database Parameters....................................................................................
A-149
xv
xvi
Preface
TheOracle Real Application Clusters Administration and Deployment Guide describes the
Oracle Real Application Clusters (Oracle RAC) architecture and provides an overview of this product, including Oracle Real Application Clusters One Node (Oracle RAC
One Node). This book also describes administrative and deployment topics for Oracle
RAC.
Information in this manual applies to Oracle RAC as it runs on all platforms unless otherwise noted. In addition, the content of this manual supplements administrative and deployment topics for noncluster Oracle databases that appear in other Oracle documentation. Where necessary, this manual refers to platform-specific documentation. This Preface includes these topics:
•
•
•
•
Audience
The Oracle Real Application Clusters Administration and Deployment Guide is intended for database administrators, network administrators, and system administrators who perform the following tasks:
• Install and configure an Oracle RAC database
• Administer and manage Oracle RAC databases
• Manage and troubleshoot clusters and networks that use Oracle RAC
Documentation Accessibility
For information about Oracle's commitment to accessibility, visit the Oracle
Accessibility Program website at http://www.oracle.com/pls/topic/lookup?
ctx=acc&id=docacc .
Access to Oracle Support
Oracle customers that have purchased support have access to electronic support through My Oracle Support. For information, visit http://www.oracle.com/pls/ topic/lookup?ctx=acc&id=info or visit http://www.oracle.com/pls/topic/lookup?
ctx=acc&id=trs if you are hearing impaired.
xvii
Related Documents
This book, the Oracle Real Application Clusters Administration and Deployment Guide, provides administration and application deployment information that is specific to
Oracle RAC. The discussions herein assume a knowledge of Oracle Clusterware.
For more information, see the Oracle resources listed in this section.
•
Oracle Database 2 Day + Real Application Clusters Guide
This task-oriented guide helps you understand the basic steps required to install, configure, and administer Oracle Clusterware and Oracle RAC on a two-node system using Red Hat Linux system.
•
Oracle Clusterware Administration and Deployment Guide
This is an essential companion book that describes Oracle Clusterware components such as the voting disks and the Oracle Cluster Registry (OCR).
• Platform-specific Oracle Clusterware and Oracle RAC installation guides
Each platform-specific Oracle Database installation media contains a copy of an
Oracle Clusterware and Oracle RAC platform-specific installation and configuration guide in HTML and PDF formats. These installation books contain the preinstallation, installation, and postinstallation information for the various
UNIX, Linux, and Windows platforms on which Oracle Clusterware and Oracle
RAC operate.
•
Oracle Database 2 Day DBA
•
Oracle Database Administrator's Guide
•
Oracle Database Net Services Administrator's Guide
•
Oracle Database Platform Guide for Microsoft Windows
•
Oracle Database Administrator's Reference for Linux and UNIX-Based Operating
Systems
•
Oracle Database 11g Administrator's Reference Release 1 (11.1) for UNIX Systems: AIX
Systems, HP-UX, Linux, and the Solaris Operating System (SPARC)
Note:
Additional information for this release may be available in the Oracle
Database 12c README or Release Notes. If these documents are available for this release, then they are on your Oracle product installation media.
Database error messages descriptions are available online or by way of a Tahiti documentation search.
Conventions
The following text conventions are used in this document:
xviii
Convention boldface
italic
monospace
Meaning
Boldface type indicates graphical user interface elements associated with an action, or terms defined in text or the glossary.
Italic type indicates book titles, emphasis, or placeholder variables for which you supply particular values.
Monospace type indicates commands within a paragraph, URLs, code in examples, text that appears on the screen, or text that you enter.
xix
Changes in This Release for Oracle Real
Application Clusters Administration and
Deployment Guide
This preface contains:
•
Changes in Oracle Real Application Clusters 12c Release 2 (12.2)
•
Changes in Oracle Real Application Clusters 12c Release 1 (12.1)
Changes in Oracle Real Application Clusters 12c Release 2 (12.2)
Following is a list of features that are new in the Oracle Real Application Clusters
Administration and Deployment Guide
for Oracle Real Application Clusters 12c release 2
(12.2).
SCAN Listener Supports HTTP Protocol
Currently, when a connection request comes in, the SCAN listener load balances among the handlers located on the same node. It then directly hands off the connection to the least loaded handler on the node. With this release, the SCAN listener is aware of the HTTP protocol so that it can redirect HTTP clients to the appropriate handler, which can reside on nodes in the cluster other than the node on which the SCAN listener resides.
IPv6 Support for Oracle Real Application Clusters on The Private Network
You can configure cluster nodes to use either IPv4- or IPv6-based IP addresses on a private network, and you can use more than one private network for a cluster.
See Also:
Oracle Clusterware Administration and Deployment Guide
Extend Oracle Database QoS Management to Fully Support Administrator-
Managed Databases
In this release, full Oracle Database Quality of Service Management (Oracle Database
QoS Management) support is available by also supporting its Management mode.
Oracle supports schema consolidation within an administrator-managed Oracle RAC database by adjusting the CPU shares of performance classes running in the database.
Additionally, database consolidation is supported by adjusting CPU counts per databases hosted on the same physical servers.
As administrator-managed databases do not run in server pools, the ability to expand or shrink the number of instances by changing the server pool size that is supported in policy-managed database deployments is not available for administrator-managed
xxi
databases. This deployment support is integrated into the Oracle Database QoS
Management pages in Oracle Enterprise Manager Cloud Control.
See Also:
Oracle Database Quality of Service Management User's Guide
Oracle Real Application Clusters Reader Nodes
Oracle RAC Reader Nodes facilitate Oracle Flex Cluster architecture by allocating a set of read/write instances running Online Transaction Processing (OLTP) workloads and a set of read-only database instances across Hub Nodes and Leaf Nodes in the cluster.
In this architecture, updates to the read-write instances are immediately propagated to the read-only instances on the Leaf Nodes, where they can be used for online reporting or instantaneous queries.
See Also:
Oracle Clusterware Administration and Deployment Guide
Server Weight-Based Node Eviction
Server weight-based node eviction acts as a tie-breaker mechanism in situations where
Oracle Clusterware must evict a particular node or a group of nodes from a cluster, in which all nodes represent an equal choice for eviction. The server weight-based node eviction mechanism helps to identify the node or the group of nodes to be evicted based on additional information about the load on those servers. Two principle mechanisms, a system-inherent automatic mechanism and a user input-based mechanism, exist to provide respective guidance.
See Also:
Oracle Clusterware Administration and Deployment Guide
Separation of Duty for Administering Oracle Real Application Clusters
Starting with Oracle Database 12c release 2 (12.2), Oracle Database provides support for separation of duty best practices when administering Oracle Real Application
Clusters (Oracle RAC) by introducing the SYSRAC administrative privilege for the clusterware agent. This feature removes the need to use the powerful SYSDBA administrative privilege for Oracle RAC.
SYSRAC, like SYSDG, SYSBACKUP and SYSKM, helps enforce separation of duties and reduce reliance on the use of SYSDBA on production systems. This administrative privilege is the default mode for connecting to the database by the clusterware agent on behalf of the Oracle RAC utilities, such as SRVCTL.
In-Memory FastStart
In-Memory FastStart optimizes the population of database objects in the In-Memory column store by storing In-Memory compression units directly on disk.
See Also:
Oracle Database In-Memory Guide
Changes in Oracle Real Application Clusters 12c Release 1 (12.1)
The following are changes in Oracle Real Application Clusters Administration and
Deployment Guide
for Oracle Real Application Clusters (Oracle RAC) 12c:
xxii
•
Changes in Oracle Real Application Clusters 12c Release 1 (12.1.0.2)
•
Changes in Oracle Real Application Clusters 12c Release 1 (12.1.0.1)
•
•
Changes in Oracle Real Application Clusters 12c Release 1 (12.1.0.2)
The following features are new in this release:
•
In-Memory Column Store
The In-Memory Column Store is an optional area in the SGA that stores whole tables, table partitions, and individual columns in a compressed columnar format.
The database uses special techniques, including SIMD vector processing, to scan columnar data extremely rapidly. The In-Memory Column Store is a supplement to, rather than a replacement for, the database buffer cache.
See Also:
Oracle Database Data Warehousing Guide
for more information
•
In-Memory Transaction Manager
The In-Memory Transaction Manager is an independent engine that automatically provides read consistency for transactions that apply changes to the In-Memory
Column Store. This engine is necessary because tables and partitions residing in the In-Memory Column Store are stored in columnar format in memory and in row-major format in the data files and database buffer cache.
See Also:
Oracle Database Concepts
for more information
•
Rapid Home Provisioning
Rapid Home Provisioning enables you to deploy Oracle homes based on images stored in a catalog of precreated software homes.
See Also:
Oracle Clusterware Administration and Deployment Guide
for more information
•
Full Database In-Memory Caching
In this release you can cache an entire database in memory. Use this feature when the buffer cache size of each instance is greater than the size of the whole database. In Oracle RAC systems, for well-partitioned applications, you can use this feature when the combined buffer caches of all database instances (with some extra space to handle duplicate cached blocks between instances) is greater than the database size.
xxiii
See Also:
Oracle Database Performance Tuning Guide
for more information
•
Memory Guard Does Not Require Oracle Database QoS Management to be
Active
With this release, Memory Guard is enabled by default independent of whether you use Oracle Database Quality of Service Management (Oracle Database QoS
Management). Memory Guard detects memory stress on a node and causes new sessions to be directed to other instances until the existing workload drains and frees memory. When free memory increases on the node, then services are enabled again to automatically accept new connections.
Changes in Oracle Real Application Clusters 12c Release 1 (12.1.0.1)
The following features are new in this release:
•
Application Continuity
Before this release, application developers were required to deal explicitly with outages of the underlying software, hardware, and communications layers if they wanted to mask outages from end users.
In Oracle Database 10g, Fast Application Notification (FAN) quickly delivered exception conditions to applications. However, neither FAN nor earlier Oracle technology reported the outcome of the last transaction to the application, or recovered the in-progress request from an application perspective. As a result, outages were exposed leading to user inconvenience and lost revenue. Users could unintentionally make duplicate purchases and submit multiple payments for the same invoice. In the problematic cases, the administrator needed to reboot the mid-tier to deal with the incoming problems this caused.
Application Continuity is an application-independent feature that attempts to recover incomplete requests from an application perspective and masks many system, communication, hardware failures, and storage outages from the end user.
See Also:
–
Oracle Database Concepts
for more information
–
Ensuring Application Continuity
•
Transaction Guard for Java
This feature exposes the new Application Continuity infrastructure to Java. It provides support for:
– At-most-once transaction execution protocol, such as transaction idempotence
– API for retrieving logical transaction ID (LTXID)
– Attribute to get Connection or Session status
xxiv
See Also:
Oracle Database JDBC Developer’s Guide
for more information
•
Transaction Idempotence
This feature delivers a general purpose, application-independent infrastructure that enables recovery of work from an application perspective and masks most system, communication, and hardware failures from the user. Transaction idempotence ensures that your transactions are executed on time and, at most, once.
See Also:
Oracle Database Development Guide
for more information
•
Oracle Flex Clusters
Large clusters consisting of, potentially, thousands of nodes, provide a platform for Oracle RAC to support massive parallel query operations.
See Also:
Oracle Clusterware Administration and Deployment Guide
for more information about Oracle Flex Clusters
•
Shared Oracle ASM Password File in a Disk Group
This feature implements the infrastructure needed to address the bootstrapping issues of storing an Oracle Automatic Storage Management (Oracle ASM) shared password file in an Oracle ASM disk group.
See Also:
Oracle Automatic Storage Management Administrator's Guide
•
Global Data Services
Similar to the way Oracle RAC supports a database service and enables servicelevel workload management across database instances in a cluster, Global Data
Services provides Oracle RAC-like connect-time and run-time load balancing, failover, and centralized service management for a set of replicated databases that offer common services. The set of databases can include Oracle RAC and nonclustered Oracle databases interconnected with Oracle Data Guard, Oracle
GoldenGate, or any other replication technology.
See Also:
Oracle Database Global Data Services Concepts and Administration Guide
for more information
•
Shared Grid Naming Service xxv
xxvi
One instance of Grid Naming Service (GNS) can service any number of clusters.
See Also:
Oracle Clusterware Administration and Deployment Guide
for more information
•
What-If Command Evaluation for Oracle RAC
This feature of Oracle Clusterware improves resource management and availability, through a mechanism that provides a policy response to a hypothetical planned or unplanned event, without modifying the state of the system.
In Oracle RAC, enhancements to SRVCTL aid you in determining the impact of certain commands before you run them to determine the potential impact of the command.
See Also:
–
" SRVCTL Usage Information " for a list of SRVCTL commands with What-
If functionality
–
Oracle Clusterware Administration and Deployment Guide
for a list of Oracle
Clusterware Control (CRSCTL) utility commands with similar enhancements
•
Restricting Service Registration for Oracle RAC Deployments
This feature allows listener registration only from local IPs by default and provides the ability to configure and dynamically update a set of IP addresses or subnets from which registration requests are allowed by the listener.
See Also:
Oracle Database Net Services Administrator's Guide
for more information
•
Restricting Service Registration with Valid Node Checking
This feature enables the network administrator to specify a list of nodes and subnet information from which the Single Client Access Name (SCAN) listener accepts registration. You can specify the nodes and subnets information using
SRVCTL, and SRVCTL stores the information in the SCAN listener resource profile and this information is also written to the listener.ora
file. Restricting client access to a database makes Oracle RAC even more secure and less vulnerable to security threads and attacks.
•
Pluggable Databases
Pluggable Databases enables an Oracle database to contain a portable collection of schemas, schema objects, and nonschema objects that appears to an Oracle Net client as a separate database. This self-contained collection is called a pluggable database (PDB). A container database (CDB) is an Oracle database that includes zero, one, or many user-created pluggable databases (PDBs). You can unplug a
PDB from a CDB and plug it into a different CDB.
See Also:
Oracle Database Administrator’s Guide
•
Support of Oracle Home User on Windows
Starting with Oracle Database 12c, Oracle Database supports the use of an Oracle home user, which you can specify at installation time. The Oracle home user is associated with a Windows domain user. The Windows domain user should be a low-privileged (non-Administrator) account to ensure that the Oracle home user has a limited set of privileges, thus ensuring that the Oracle Database services have only those privileges required to run Oracle products.
Windows Administrator user privileges are still required to perform Oracle software maintenance tasks including installation, upgrade, patching, and so on.
Oracle Database administrative tools have been enhanced to ask for the password of the Oracle home user, if needed. In Oracle RAC environments, you can store the password for the Oracle home user in a secure wallet. If such a wallet exists, then the Oracle Database administrative tools automatically use the password from the wallet and do not require the user to enter the password for the Oracle home user.
See Also:
Oracle Real Application Clusters Installation Guide for Microsoft Windows x64 (64-
Bit)
•
Cluster Resources for Oracle ACFS and Oracle ADVM
Oracle Clusterware resource support includes enhancements for Oracle homes stored on Oracle Automatic Storage Management Cluster File System (Oracle
ACFS), Oracle ACFS General Purpose file systems for Grid homes, and Oracle
ASM Dynamic Volume Manager (Oracle ADVM) volumes. These resources, that
Oracle Clusterware manages, support automatic loading of Oracle ACFS, Oracle
ADVM and OKS drivers, disk group mounts, dynamic volume enablement, and automatic Oracle ACFS file system mounts.
See Also:
Oracle Automatic Storage Management Administrator's Guide
for more information
•
Oracle Highly Available NFS
You can configure Oracle ACFS as a highly available, exported file system service.
This service uses Oracle ACFS' clusterwide data consistency and coherency, in combination with virtual IP addresses, to provide failover capability for NFS exports. By mounting the NFS export from this virtual IP address, a client can be assured that, if one node of the cluster is available, then the NFS export will be available.
xxvii
See Also:
Oracle Automatic Storage Management Administrator's Guide
for more information
•
Policy-Based Cluster Management and Administration
Oracle Grid Infrastructure allows running multiple applications in one cluster.
Using a policy-based approach, the workload introduced by these applications can be allocated across the cluster using a policy. In addition, a policy set enables different policies to be applied to the cluster over time as required. You can define policy sets using a web-based interface or a command-line interface.
Hosting various workloads in the same cluster helps to consolidate the workloads into a shared infrastructure that provides high availability and scalability. Using a centralized policy-based approach allows for dynamic resource reallocation and prioritization as the demand changes.
See Also:
Oracle Clusterware Administration and Deployment Guide
for more information
•
Online Resource Attribute Modification
Oracle Clusterware manages hardware and software components for high availability using a resource model. You use resource attributes to define how
Oracle Clusterware manages those resources. You can modify certain resource attributes and implement those changes without having to restart the resource using online resource attribute modification. You manage online resource attribute modification with certain SRVCTL and CRSCTL commands.
Deprecated Features
Deprecation of single-letter SRVCTL CLI options
All SRVCTL commands have been enhanced to accept full-word options instead of the single-letter options. All new SRVCTL command options added in this release support full-word options, only, and do not have single-letter equivalents. The use of singleletter options with SRVCTL commands might be desupported in a future release.
Desupported Features
See Also:
Oracle Database Upgrade Guide
for more information
•
Oracle Cluster File System for Windows
Oracle no longer supports Oracle Cluster File System (OCFS) on Windows.
•
Raw (block) storage devices for Oracle Database and related technologies
Oracle Database 12c release 1 (12.1) and its related grid technologies, such as
Oracle Clusterware, no longer support the direct use of raw or block storage
xxviii
devices. You must move existing files from raw or block devices to Oracle ASM before you upgrade to Oracle Clusterware 12c release 1 (12.1).
xxix
1
Introduction to Oracle RAC
Provides an overview of Oracle Real Application Clusters (Oracle RAC) installation and administration, and various components and functions.
This chapter includes the following topics:
•
•
Overview of Installing Oracle RAC
•
Overview of Oracle Real Application Clusters One Node
•
Overview of Oracle Clusterware for Oracle RAC
•
Overview of Oracle RAC Architecture and Processing
•
Overview of Automatic Workload Management with Dynamic Database Services
•
Overview of Server Pools and Policy-Managed Databases
•
Overview of Oracle Database Quality of Service Management
•
•
Overview of Oracle Multitenant with Oracle RAC
•
Overview of Database In-Memory and Oracle RAC
•
Overview of Managing Oracle RAC Environments
Overview of Oracle RAC
Provides an introduction to Oracle RAC and its functionality.
Non-cluster Oracle databases have a one-to-one relationship between the Oracle database and the instance. Oracle RAC environments, however, have a one-to-many relationship between the database and instances. An Oracle RAC database can have
all of which access one database. All database instances must use
the same interconnect, which can also be used by Oracle Clusterware.
Oracle RAC databases differ architecturally from non-cluster Oracle databases in that each Oracle RAC database instance also has:
• At least one additional thread of redo for each instance
• An instance-specific undo tablespace
1
With Oracle Database 10g release 2 (10.2) and later releases, Oracle Clusterware supports 100 nodes in an Oracle
Clusterware standard Cluster, with the option to run 100 database instances belonging to one production database on these nodes.
Introduction to Oracle RAC 1-1
Overview of Oracle RAC
The combined processing power of the multiple servers can provide greater throughput and Oracle RAC scalability than is available from a single server.
comprises multiple interconnected computers or servers that appear as if they are one server to end users and applications. The Oracle RAC option with Oracle
Database enables you to cluster Oracle databases. Oracle RAC uses Oracle
Clusterware for the infrastructure to bind multiple servers so they operate as a single system.
Oracle Clusterware is a portable cluster management solution that is integrated with
Oracle Database. Oracle Clusterware is a required component for using Oracle RAC that provides the infrastructure necessary to run Oracle RAC. Oracle Clusterware also
Virtual Internet Protocol (VIP)
listeners, services, and so on. In addition, Oracle Clusterware enables both noncluster
Oracle databases and Oracle RAC databases to use the Oracle high-availability infrastructure. Oracle Clusterware along with Oracle Automatic Storage Management
(Oracle ASM) (the two together comprise the
to create a clustered pool of storage to be used by any combination of noncluster and
Oracle RAC databases.
Oracle Clusterware is the only clusterware that you need for most platforms on which
Oracle RAC operates. If your database applications require vendor clusterware, then you can use such clusterware in conjunction with Oracle Clusterware if that vendor clusterware is certified for Oracle RAC.
Figure 1-1 shows how Oracle RAC is the Oracle Database option that provides a single
system image for multiple servers to access one Oracle database. In Oracle RAC, each
Oracle instance must run on a separate server.
Figure 1-1 Oracle Database with Oracle RAC Architecture
Application / Web Servers
HR
Sales
Call Center
HR
Sales
Call Center
Oracle Net Services Client Access
HR Service
Node 1
Instance 1 hb hb
Sales Service
Node 2
Instance 2 hb hb
HR
Sales
Call Center
Call Center Service
Node 3
Instance 3
RAC
Database
Heartbeat hb
1-2 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Installing Oracle RAC
Traditionally, an Oracle RAC environment is located in one data center. However, you can configure Oracle RAC on an
, which is an architecture that provides extremely fast recovery from a site failure and allows for all nodes, at all sites, to actively process transactions as part of a single database cluster. In an extended cluster, the nodes in the cluster are typically dispersed, geographically, such as between two fire cells, between two rooms or buildings, or between two different data centers or cities. For availability reasons, the data must be located at both sites, thus requiring the implementation of disk mirroring technology for storage.
If you choose to implement this architecture, you must assess whether this architecture is a good solution for your business, especially considering distance, latency, and the degree of protection it provides. Oracle RAC on extended clusters provides higher availability than is possible with local Oracle RAC configurations, but an extended cluster may not fulfill all of the disaster-recovery requirements of your organization. A feasible separation provides great protection for some disasters (for example, local power outage or server room flooding) but it cannot provide protection against all types of outages. For comprehensive protection against disasters—including protection against corruptions and regional disasters—Oracle recommends the use of
Oracle Data Guard with Oracle RAC, as described in the Oracle Data Guard Concepts
and Administration
and on the Maximum Availability Architecture (MAA) Web site.
Oracle RAC is a unique technology that provides high availability and scalability for all application types. The Oracle RAC infrastructure is also a key component for implementing the Oracle enterprise grid computing architecture. Having multiple instances access a single database prevents the server from being a single point of failure. Oracle RAC enables you to combine smaller commodity servers into a cluster to create scalable environments that support mission critical business applications.
Applications that you deploy on Oracle RAC databases can operate without code changes.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Oracle Grid Infrastructure Installation and Upgrade Guide
Oracle Data Guard Concepts and Administration
Maximum Availability Architecture (MAA)
Overview of Installing Oracle RAC
Install Oracle Grid Infrastructure and Oracle Database software using Oracle
Universal Installer, and create your database with Database Configuration Assistant
(DBCA).
This ensures that your Oracle RAC environment has the optimal network configuration, database structure, and parameter settings for the environment that you selected.
Alternatively, you can install Oracle RAC using Rapid Home Provisioning, which offers all of the advantages of Oracle Universal Installer and DBCA previously specified. In addition, Rapid Home Provisioning allows for standardization and automation.
This section introduces the installation processes for Oracle RAC under the following topics:
•
Understanding Compatibility in Oracle RAC Environments
Introduction to Oracle RAC 1-3
Overview of Installing Oracle RAC
•
Oracle RAC Database Management Styles and Database Installation
•
Oracle RAC Database Management Styles and Database Creation
•
Overview of Extending an Oracle RAC Cluster
Note:
You must first install Oracle Grid Infrastructure before installing Oracle RAC.
Related Topics:
Oracle Real Application Clusters Installation Guide
Oracle Grid Infrastructure Installation and Upgrade Guide
Understanding Compatibility in Oracle RAC Environments
To run Oracle RAC in configurations with different versions of Oracle Database in the same cluster, you must first install Oracle Grid Infrastructure, which must be the same version, or higher, as the highest version of Oracle Database that you want to deploy in this cluster. For example, to run an Oracle RAC 11g release 2 (11.2) database and an
Oracle RAC 12c database in the same cluster, you must install Oracle Grid
Infrastructure 12c. Contact My Oracle Support for more information about version compatibility in Oracle RAC environments.
Note:
Oracle does not support deploying an Oracle9i cluster in an Oracle Grid
Infrastructure 12c environment.
Oracle RAC Database Management Styles and Database Installation
Before installing the Oracle RAC database software and creating respective databases, decide on the management style you want to apply to the Oracle RAC databases, as described in "Overview of Server Pools and Policy-Managed Databases".
The management style you choose impacts the software deployment and database creation. If you choose the administrator-managed database deployment model, using a per-node installation of software, then it is sufficient to deploy the Oracle Database software (the database home) on only those nodes on which you plan to run Oracle
Database.
If you choose the policy-managed deployment model, using a per-node installation of software, then you must deploy the software on all nodes in the cluster, because the dynamic allocation of servers to server pools, in principle, does not predict on which server a database instance can potentially run. To avoid instance startup failures on servers that do not host the respective database home, Oracle strongly recommends that you deploy the database software on all nodes in the cluster. When you use a shared Oracle Database home, accessibility to this home from all nodes in the cluster is assumed and the setup needs to ensure that the respective file system is mounted on all servers, as required.
Oracle Universal Installer will only allow you to deploy an Oracle Database home across nodes in the cluster if you previously installed and configured Oracle Grid
Infrastructure for the cluster. If Oracle Universal Installer does not give you an option
1-4 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Installing Oracle RAC to deploy the database home across all nodes in the cluster, then check the prerequisite, as stated, by Oracle Universal Installer.
During installation, you can choose to create a database during the database home installation. Oracle Universal Installer runs DBCA to create your Oracle RAC database according to the options that you select.
See Also:
"Oracle RAC Database Management Styles and Database Creation" for more information if you choose this option
Note:
Before you create a database, a default listener must be running in the Oracle
Grid Infrastructure home. If a default listener is not present in the Oracle Grid
Infrastructure home, then DBCA returns an error instructing you to run
NETCA from the Oracle Grid Infrastructure home to create a default listener.
The Oracle RAC software is distributed as part of the Oracle Database installation media. By default, the Oracle Database software installation process installs the Oracle
RAC option when it recognizes that you are performing the installation on a cluster.
Oracle Universal Installer installs Oracle RAC into a directory structure referred to as the Oracle home, which is separate from the Oracle home directory for other Oracle software running on the system. Because Oracle Universal Installer is cluster aware, it installs the Oracle RAC software on all of the nodes that you defined to be part of the cluster.
Related Topics:
Overview of Server Pools and Policy-Managed Databases
Server pools are the basis for policy-managed databases.
Oracle RAC Database Management Styles and Database Creation
Part of Oracle Database deployment is the creation of the database.
Oracle Database Net Services Administrator's Guide
Oracle RAC Database Management Styles and Database Creation
Part of Oracle Database deployment is the creation of the database.
You can choose to create a database as part of the database software deployment, as described in "Oracle RAC Database Management Styles and Database Installation", or you can choose to only deploy the database software, first, and then, subsequently, create any database that is meant to run out of the newly created Oracle home by using DBCA. In either case, you must consider the management style that you plan to use for the Oracle RAC databases.
For administrator-managed databases, you must ensure that the database software is deployed on the nodes on which you plan to run the respective database instances.
You must also ensure that these nodes have access to the storage in which you want to store the database files. Oracle recommends that you select Oracle ASM during database installation to simplify storage management. Oracle ASM automatically manages the storage of all database files within disk groups. If you plan to use Oracle
Introduction to Oracle RAC 1-5
Overview of Installing Oracle RAC
Database Standard Edition to create an Oracle RAC database, then you must use
Oracle ASM to store all of the database files.
For policy-managed databases, you must ensure that the database software is deployed on all nodes on which database instances can potentially run, given your active server pool setup. You must also ensure that these nodes have access to the storage in which you want to store the database files. Oracle recommends using Oracle
ASM, as previously described for administrator-managed databases.
Server pools are a feature of Oracle Grid Infrastructure (specifically Oracle
Clusterware). There are different ways you can set up server pools on the Oracle
Clusterware level, and Oracle recommends you create server pools for database management before you create the respective databases. DBCA, however, will present you with a choice of either using precreated server pools or creating a new server pool, when you are creating a policy-managed database. Whether you can create a new server pool during database creation depends on the server pool configuration that is active at the time.
By default, DBCA creates one service for your Oracle RAC installation. This is the default database service and should not be used for user connectivity. The default database service is typically identified using the combination of the
DB_NAME
and
DB_DOMAIN
initialization parameters:
db_name.db_domain
. The default service is available on all instances in an Oracle RAC environment, unless the database is in restricted mode.
Note:
Oracle recommends that you reserve the default database service for maintenance operations and create dynamic database services for user or application connectivity as a post-database-creation step, using either SRVCTL or Oracle Enterprise Manager. DBCA no longer offers a dynamic database service creation option for Oracle RAC databases. For Oracle RAC One Node databases, you must create at least one dynamic database service.
Related Topics:
Oracle RAC Database Management Styles and Database Installation
Oracle Clusterware Administration and Deployment Guide
Overview of Extending an Oracle RAC Cluster
If you want to extend the Oracle RAC cluster (also known as cloning) and add nodes to the existing environment after your initial deployment, then you must to do this on multiple layers, considering the management style that you currently use in the cluster.
Oracle provides various means of extending an Oracle RAC cluster. In principle, you can choose from the following approaches to extend the current environment:
• Rapid Home Provisioning to provision new Oracle RAC databases and other software
• Cloning using cloning scripts
• Adding nodes using the addnode.sh
( addnode.bat
on Windows) script
1-6 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Installing Oracle RAC
Both approaches are applicable, regardless of how you initially deployed the environment. Both approaches copy the required Oracle software on to the node that you plan to add to the cluster. Software that gets copied to the node includes the
Oracle Grid Infrastructure software and the Oracle database homes.
For Oracle database homes, you must consider the management style deployed in the cluster. For administrator-managed databases, you must ensure that the database software is deployed on the nodes on which you plan to run the respective database instances. For policy-managed databases, you must ensure that the database software is deployed on all nodes on which database instances can potentially run, given your active server pool setup. In either case, you must first deploy Oracle Grid
Infrastructure on all nodes that are meant to be part of the cluster.
Note:
Oracle cloning is not a replacement for cloning using Oracle Enterprise
Manager as part of the Provisioning Pack. When you clone Oracle RAC using
Oracle Enterprise Manager, the provisioning process includes a series of steps where details about the home you want to capture, the location to which you want to deploy, and various other parameters are collected.
For new installations or if you install only one Oracle RAC database, use the traditional automated and interactive installation methods, such as Oracle Universal
Installer, Rapid Home Provisioning, or the Provisioning Pack feature of Oracle
Enterprise Manager. If your goal is to add or delete Oracle RAC from nodes in the cluster, you can use the procedures detailed in "Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems".
The cloning process assumes that you successfully installed an Oracle Clusterware home and an Oracle home with Oracle RAC on at least one node. In addition, all root scripts must have run successfully on the node from which you are extending your cluster database.
Related Topics:
Cloning Oracle RAC to Nodes in a New Cluster
This chapter describes how to clone Oracle Real Application Clusters
(Oracle RAC) database homes on Linux and UNIX systems to nodes in a new cluster.
Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems
Extend an existing Oracle Real Application Clusters (Oracle RAC) home to other nodes and instances in the cluster, and delete Oracle RAC from nodes and instances in the cluster.
Adding and Deleting Oracle RAC from Nodes on Windows Systems
Oracle Clusterware Administration and Deployment Guide
Introduction to Oracle RAC 1-7
Overview of Oracle Real Application Clusters One Node
See Also:
•
Oracle Clusterware Administration and Deployment Guide
for more information about Rapid Home Provisioning
• Oracle Enterprise Manager online help system for more information about the Provisioning Pack
Overview of Oracle Real Application Clusters One Node
Oracle Real Application Clusters One Node (Oracle RAC One Node) is an option to
Oracle Database Enterprise Edition available since Oracle Database 11g release 2 (11.2).
Oracle RAC One Node is a single instance of an Oracle RAC-enabled database running on one node in the cluster, only, under normal operations. This option adds to the flexibility that Oracle offers for database consolidation while reducing management overhead by providing a standard deployment for Oracle databases in the enterprise. Oracle RAC One Node database requires Oracle Grid Infrastructure and, therefore, requires the same hardware setup as an Oracle RAC database.
Oracle supports Oracle RAC One Node on all platforms on which Oracle RAC is certified. Similar to Oracle RAC, Oracle RAC One Node is certified on Oracle Virtual
Machine (Oracle VM). Using Oracle RAC or Oracle RAC One Node with Oracle VM increases the benefits of Oracle VM with the high availability and scalability of Oracle
RAC.
With Oracle RAC One Node, there is no limit to server scalability and, if applications grow to require more resources than a single node can supply, then you can upgrade your applications online to Oracle RAC. If the node that is running Oracle RAC One
Node becomes overloaded, then you can relocate the instance to another node in the cluster. With Oracle RAC One Node you can use the Online Database Relocation feature to relocate the database instance with no downtime for application users.
Alternatively, you can limit the CPU consumption of individual database instances per server within the cluster using Resource Manager Instance Caging and dynamically change this limit, if necessary, depending on the demand scenario.
Using the Single Client Access Name (SCAN) to connect to the database, clients can locate the service independently of the node on which it is running. Relocating an
Oracle RAC One Node instance is therefore mostly transparent to the client, depending on the client connection. Oracle recommends to use either Application
Continuity and Oracle Fast Application Notification or Transparent Application
Failover to minimize the impact of a relocation on the client.
Oracle RAC One Node databases are administered slightly differently from Oracle
RAC or non-cluster databases. For administrator-managed Oracle RAC One Node databases, you must monitor the candidate node list and make sure a server is always available for failover, if possible. Candidate servers reside in the Generic server pool and the database and its services will fail over to one of those servers.
For policy-managed Oracle RAC One Node databases, you must ensure that the server pools are configured such that a server will be available for the database to fail over to in case its current node becomes unavailable. In this case, the destination node for online database relocation must be located in the server pool in which the database is located. Alternatively, you can use a server pool of size 1 (one server in the server pool), setting the minimum size to 1 and the importance high enough in relation to all other server pools used in the cluster, to ensure that, upon failure of the one server
1-8 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Oracle Clusterware for Oracle RAC used in the server pool, a new server from another server pool or the Free server pool is relocated into the server pool, as required.
Note:
• Oracle RAC One Node supports Transaction Guard and Application
Continuity for failing clients over.
• To prepare for all failure possibilities, you must add at least one Dynamic
Database Service (Oracle Clusterware-managed database service) to an
Oracle RAC One Node database.
Related Topics:
Oracle Real Application Clusters Installation Guide for Linux and UNIX
Transaction Guard for Improving Client Failover
Transaction Guard prevents a transaction being replayed by Application
Continuity from being applied more than once.
Overview of Oracle Clusterware for Oracle RAC
Oracle Clusterware provides a complete, integrated clusterware management solution on all Oracle Database platforms.
This clusterware functionality provides all of the features required to manage your cluster database including node membership, group services, global resource management, and high availability functions.
You can install Oracle Clusterware independently or as a prerequisite to the Oracle
RAC installation process. Oracle Database features, such as services, use the underlying Oracle Clusterware mechanisms to provide advanced capabilities. Oracle
Database also continues to support select third-party clusterware products on specified platforms.
Oracle Clusterware is designed for, and tightly integrated with, Oracle RAC. You can use Oracle Clusterware to manage high-availability operations in a cluster. When you create an Oracle RAC database using any of the management tools, the database is registered with and managed by Oracle Clusterware, along with the other required components such as the VIP address, the Single Client Access Name (SCAN) (which includes the SCAN VIPs and the SCAN listener), Oracle Notification Service, and the
Oracle Net listeners. These resources are automatically started when the node starts and automatically restart if they fail. The Oracle Clusterware daemons run on each node.
Anything that Oracle Clusterware manages is known as a CRS resource. A CRS resource can be a database, an instance, a service, a listener, a VIP address, or an application process. Oracle Clusterware manages CRS resources based on the resource's configuration information that is stored in the Oracle Cluster Registry
(OCR). You can use SRVCTL commands to administer any Oracle-defined CRS resources. Oracle Clusterware provides the framework that enables you to create CRS resources to manage any process running on servers in the cluster which are not predefined by Oracle. Oracle Clusterware stores the information that describes the configuration of these components in OCR that you can administer.
Introduction to Oracle RAC 1-9
Overview of Oracle Clusterware for Oracle RAC
Another advantage with Oracle Flex Clusters is that you can convert Hub Nodes to
Leaf Nodes and vice versa, and you can convert a Leaf Node to a Hub Node with no downtime.
This section includes the following topics:
•
Overview of Oracle Flex Clusters
•
•
Overview of Local Temporary Tablespaces
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Oracle Clusterware Administration and Deployment Guide
Overview of Oracle Flex Clusters
Oracle Flex Clusters provide a platform for a variety of applications, including Oracle
RAC databases with large numbers of nodes.
Oracle Flex Clusters also provide a platform for other service deployments that require coordination and automation for high availability.
All nodes in an Oracle Flex Cluster belong to a single Oracle Grid Infrastructure cluster. This architecture centralizes policy decisions for deployment of resources based on application needs, to account for various service levels, loads, failure responses, and recovery.
Oracle Flex Clusters contain two types of nodes arranged in a hub and spoke
s. The number of Hub Nodes in an Oracle
Flex Cluster can be as many as 64. The number of Leaf Nodes can be many more. Hub
Nodes and Leaf Nodes can host different types of applications.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Overview of Reader Nodes
Reader nodes are instances of an Oracle RAC database that run on Leaf Nodes in an
Oracle Flex Cluster, a feature that was unavailable in previous Oracle Clusterware releases.
An advantage of using reader nodes is that these instances are not affected if you need to reconfigure a Hub Node. Parallel query jobs running on reader nodes are not subject to the brownout times that can occur when you reconfigure a Hub Node, and can continue to service clients that are connected to the reader nodes, as long as the
Hub Node to which it is connected is not evicted from the cluster. You can scale up to
64 reader nodes per Hub Node, and reader nodes can utilize massive parallel query to speed up operations on large data sets.
Database instances running on reader nodes have different characteristics than database instances running on Hub Nodes. Hub Node instances are similar to previous versions of Oracle RAC database instances, whereas instances running on reader nodes have the following notable differences:
• Database instances run in read-only mode.
1-10 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Oracle Clusterware for Oracle RAC
• Database instances are unaffected if you reconfigure Hub Node clusterware.
Database instances running on reader nodes are not subject to the brownout times and can continue to service the clients connected to the reader nodes, as long as the Hub Node to which it is connected is not evicted from the cluster. Using reader nodes, you can scale up to 64 reader nodes per hub.
• Because database instances running on the reader nodes are read only, you will receive an error if you attempt any DDL or DML operations.
You can create services to direct queries to read-only instances running on reader nodes. These services can use parallel query to further speed up performance. Oracle recommends that you size the memory in these reader nodes as high as possible so that parallel queries can use the memory for best performance.
Overview of Local Temporary Tablespaces
To improve I/O operations, Oracle introduces a local temporary tablespace in Oracle
Database 12c release 2 (12.2), so that spill-overs are written to the local disks on the reader nodes.
It is still possible for SQL operations, such as hash aggregation, sort, hash join, creation of cursor-duration temporary tables for the
WITH
clause, and star transformation to spill over to disk (specifically to the global temporary tablespace on shared disks).
Management of the local temporary tablespace is similar to that of the existing temporary tablespace.
Local temporary tablespaces improve temporary tablespace management in read-only instances by:
• Storing temp files in reader node private storage to take advantage of the I/O benefits of local storage.
• Avoiding expensive cross-instance temporary tablespace management.
• Increased addressability of temporary tablespace.
• Improving instance warm-up performance by eliminating on-disk space metadata management.
Note:
You cannot use local temporary tablespaces to store database objects, such as tables or indexes. This same restriction is also true for space for Oracle global temporary tables.
This section includes the following topics:
•
Parallel Execution Support for Cursor-Duration Temporary Tablespaces
•
Local Temporary Tablespace Organization
•
Temporary Tablespace Hierarchy
•
Local Temporary Tablespace Features
•
Metadata Management of Local Temporary Files
•
DDL Support for Local Temporary Tablespaces
•
Local Temporary Tablespaces for Users
Introduction to Oracle RAC 1-11
Overview of Oracle Clusterware for Oracle RAC
•
Atomicity Requirement for Commands
•
Local Temporary Tablespace and Dictionary Views
Parallel Execution Support for Cursor-Duration Temporary Tablespaces
The temporary tablespaces created for the
WITH
clause and star transformation exist in the temporary tablespace on the shared disk. A set of parallel query child processes load intermediate query results into these temporary tablespaces, which are then read later by a different set of child processes. There is no restriction on how these child processes reading these results are allocated, as any parallel query child process on any instance can read the temporary tablespaces residing on the shared disk.
For read-write and read-only instance architecture, as the parallel query child processes load intermediate results to the local temporary tablespaces of these instances, the parallel query child processes belonging to the instance where the intermediate results are stored share affinity with the reads for the intermediate results and can thus read them.
Local Temporary Tablespace Organization
You can create local temporary tablespace using the
{FOR_RIM | FOR ALL} extension, as follows:
CREATE LOCAL TEMPORARY TABLESPACE FOR RIM local_temp_ts_for_rim TEMPFILE\
'/u01/app/oracle/database/12.2.0.1/dbs/temp_file_rim'\
EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M AUTOEXTEND ON;
• Creation of a local temporary tablespace results in the creation of local temporary files on every instance and not a single file, as is currently true for shared global temporary tablespaces.
• You can create local temporary tablespaces for both read-only and read-write instances. The
LOCAL FOR RIM
option creates a local temporary tablespace whose files reside on local disks for read-only instances. The
LOCAL FOR ALL option creates a local temporary tablespace whose files reside on local disks for both read-write and read-only instances. For example:
CREATE LOCAL TEMPORARY TABLESPACE FOR ALL temp_ts_for_all TEMPFILE\
‘/u01/app/oracle/database/12.2.0.1/dbs/temp_file_all’\
EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M AUTOEXTEND ON;
Temporary Tablespace Hierarchy
When you define local temporary tablespace and shared (existing) temporary tablespace, there is a hierarchy in which they are used. To understand the hierarchy, remember that there can be multiple shared temporary tablespaces in a database, such the default shared temporary tablespace for the database and multiple temporary tablespaces assigned to individual users. If a user has a shared temporary tablespace assigned, then that tablespace is used first, otherwise the database default temporary tablespace is used.
Once a tablespace has been selected for spilling during query processing, there is no switching to another tablespace. For example, if a user has a shared temporary tablespace assigned and during spilling it runs out of space, then there is no switching to an alternative tablespace. The spilling, in that case, will result in an error.
Additionally, remember that shared temporary tablespaces are shared among instances.
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The allocation of temporary space for spilling to a local temporary tablespace differs between read-only and read-write instances. For read-only instances, the following is the priority of selecting which temporary location to use for spills:
1.
2.
Allocate from a user's local temporary tablespace.
Allocate from the database default local temporary tablespace.
3.
4.
Allocate from a user's temporary tablespace.
Allocate from the database default temporary tablespace.
Note:
If there is no local temporary tablespace in the database, then read-only instances will spill to shared temporary tablespace.
For read-write instances, the priority of allocation differs from the preceding allocation order, as shared temporary tablespaces are given priority, as follows:
1.
Allocate from a user’s shared temporary tablespace.
2.
3.
4.
Allocate from a user’s local temporary tablespace.
Allocate from the database default shared temporary tablespace.
Allocate from the database default local temporary tablespace.
Note:
For read-write instances to use a local temporary tablespace, that temporary tablespace must be created with the
LOCAL...FOR ALL
option.
Local Temporary Tablespace Features
Instances cannot share local temporary tablespace, hence one instance cannot take local temporary tablespace from another. If an instance runs out of temporary tablespace during spilling, then the statement resutls in an error.
• Local temporary tablespace support only one
BIGFILE
per tablespace.
• To address contention issues arising from having only one
BIGFILE
-based local temporary tablespace, multiple local temporary tablespaces can be assigned to different users, as default.
• A database administrator can specify the default temporary tablespace for a user using
ALTER USER
syntax. For example:
ALTER USER MAYNARD LOCAL TEMPORARY TABLESPACE temp_ts_for_rim;
• A user can be configured with two default temporary tablespaces:
– One local temporary (created with the
FOR RIM
option) when the user is connected to the read-only instance running on reader nodes.
– One shared temporary tablespace to be used when the same user is connected on the read-write instances running on a Hub Node.
Metadata Management of Local Temporary Files
Currently, temporary file information (such as file name, creation size, creation SCN, temporary block size, and file status) is stored in the control file along with the initial
Introduction to Oracle RAC 1-13
Overview of Oracle Clusterware for Oracle RAC and max files, as well as auto extent attributes. However, the information about local temporary files in the control file is common to all applicable instances (read write and read only for
LOCAL...FOR ALL
, and read only for
LOCAL...FOR RIM
).
Instance-specific information, such as bitmap for allocation, current size for a temporary file, and the file status, is stored in the SGA on instances and not in the control file because this information can be different for different instances. When an instance starts up, it reads the information in the control file and creates the temporary files that constitute the local temporary tablespace for that instance. If there are two or more instances running on a node, then each instance will have its own local temporary files.
For local temporary tablespaces, there is a separate file for each involved instance. If you create the local temporary tablespace using the LOCAL...FOR RIM option, then
Oracle creates files only on read-only instances. If you create the local temporary tablespace using the LOCAL...FOR ALL option, then Oracle creates files on all instances. The local temporary file names follow a naming convention such that the instance numbers are appended to the temporary file names specified while creating the local temporary tablespace.
For example, assume that a read-only node, N1, runs two Oracle read-only database instances with numbers 3 and 4. The following DDL command creates two files on node N1—
/temp/temp_file_rim_3
and
/temp/temp_file_rim_4
, for instance
3 and 4 respectively:
CREATE LOCAL TEMPORARY TABLESPACE FOR RIM temp_ts_for_rim TEMPFILE '/temp/ temp_file_rim'\
EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M AUTOEXTEND ON;
Assuming that there are two read-write instances (instance numbers 1 and 2) and two read-only instances (instance numbers 3 and 4), the following DDL command creates four files—
/temp/temp_file_all_1
and
/temp/temp_file_all_2
for instances
1 and 2, respectively, and
/temp/temp_file_all_3
and
/temp/ temp_file_all_4
for instances 3 and 4, respectively:
CREATE LOCAL TEMPORARY TABLESPACE FOR ALL temp_ts_for_all TEMPFILE '/temp/ temp_file_all'\
EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M AUTOEXTEND ON;
DDL Support for Local Temporary Tablespaces
You manage local temporary tablespaces and temporary files with either
ALTER
TABLESPACE
,
ALTER DATABASE
, or both DDL commands. All DDL commands related to local temporary tablespace management and creation are run from the readwrite instances. Running all other DDL commands will affect all instances in a homogeneous manner.
For example, the following command resizes the temporary files on all read-only instances:
ALTER TABLESPACE temp_ts_for_rim RESIZE 1G;
For local temporary tablespaces, Oracle supports the allocation options and their restrictions currently active for temporary files.
To run a DDL command on a local temporary tablespace on a read-only instance, only
(in particular,
CREATE LOCAL TABLESPACE...FOR RIM
or
ALTER TABLESPACE
LOCAL TABLESPACE...FOR RIM
), there must be at least one read-only instance in the cluster. This restriction is not applicable when creating or altering local temporary tablespaces
FOR ALL
. Users can assign a default local temporary tablespace to the
1-14 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Oracle Clusterware for Oracle RAC database with a
DEFAULT LOCAL TEMPORARY TABLESPACE
clause appended to the
ALTER DATABASE
command.
Note:
The annotation
FOR RIM
is unnecessary because it is implied by the name of the table space.
For example:
ALTER DATABASE DEFAULT LOCAL TEMPORARY TABLESPACE temp_ts_for_rim;
A database administrator can specify default temporary tablespace when creating the database, as follows:
CREATE DATABASE .. DEFAULT TEMPORARY TABLESPACE temp_ts_for_dbtemp_ts_for_rim
TEMPFILE\
'/temp/temp_file_for_dbrim' EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M AUTOEXTEND ON;
It is not possible to specify default local temporary tablespaces using the
CREATE
DATABASE
command. When you create a database, its default local temporary tablespace will point to the default shared temporary tablespace. Database administrators must run the
ALTER DATABASE
command to assign an existing local temporary tablespace as the default for the database.
Local Temporary Tablespace for Users
When you create a user without explicitly specifying shared or local temporary tablespace, the user inherits shared and local temporary tablespace from the corresponding default database tablespaces. You can specify default local temporary tablespace for a user, as follows:
CREATE USER new_user IDENTIFIED BY new_user LOCAL TEMPORARY TABLESPACE temp_ts_for_all;
You can change the local temporary tablespace for a user using the
ALTER USER command, as follows:
ALTER USER maynard LOCAL TEMPORARY TABLESPACE temp_ts_for_rim;
As previously mentioned, default user local temporary tablespace can be shared temporary space. Consider the following items for the
ALTER USER...TEMPORARY
TABLESPACE
command:
• You can change the user default local temporary tablespace to any existing local temporary tablespace.
• If you want to set the user default local temporary tablespace to a shared temporary tablespace,
T
, then
T
must be the same as the default shared temporary tablespace.
• If a default user local temporary tablespace points to a shared temporary tablespace, then, when you change the default shared temporary tablespace of the user, you also change the default local temporary tablespace to that tablespace.
Following are some examples of local temporary space management using the
ALTER command:
• To take a local temporary tablespace offline:
ALTER DATABASE TEMPFILE ‘/temp/temp_file_rim’ OFFLINE;
Introduction to Oracle RAC 1-15
Overview of Oracle Clusterware for Oracle RAC
• To decrease the size of a local temporary tablespace:
ALTER TABLESPACE temp_ts_for_rim SHRINK SPACE KEEP 20M
• To change the auto-extension attributes of a local temporary file:
ALTER TABLESPACE temp_ts_for_rim AUTOEXTEND ON NEXT 20G
• To resize a local temporary file:
ALTER TABLESPACE temp_ts_for_rim RESIZE 10G
Note:
When you resize a local temporary file, it applies to individual files.
Some read-only instances may be down when you run any of the preceding commands. This does not prevent the commands from succeeding because, when a read-only instance starts up later, it creates the temporary files based on information in the control file. Creation is fast because Oracle reformats only the header block of the temporary file, recording information about the file size, among other things. If you cannot create any of the temporary files, then the read-only instance stays down.
Commands that were submitted from a read-write instance are replayed, immediately, on all open read-only instances.
Atomicity Requirement for Commands
All the commands that you run from the read-write instances are performed in an atomic manner, which means the command succeeds only when it succeeds on all live instances.
Local Temporary Tablespace and Dictionary Views
Oracle extended dictionary views to display information about local temporary tablespaces. Oracle made the following changes:
• All the diagnosibility information related to temporary tablespaces and temporary files exposed through AWR, SQL monitor, and other utilities, is also available for local temporary tablespaces and local temporary files. This information is available with the exisiting dictionary views for temporary tablespaces and temporary files:
DBA_TEMP_FILES
,
DBA_TEMP_FREE_SPACE
.
• The
USER_TABLESPACES
and
DBA_TABLESPACES
dictionary view are extended by a column, called
SHARED
, that indicates whether the temporary file is local
(
FOR RIM
or
FOR ALL
) or shared.
• The
DBA_TEMP_FILES
dictionary view is extended by two columns:
SHARED
and
INST_ID
. The
SHARED
column indicates whether the temp file is local (
FOR RIM or
FOR ALL
) or shared. The
INST_ID
column contains the instance number. For shared temporary files, there is a single row per file, and the
INST_ID
is null. For local temporary files, this column contains information about temporary files per instance, such as the size of the file in bytes (
BYTES
column).
Note:
LOCAL...FOR RIM
shows only read-only instances per file.
• The
DBA_TEMP_FREE_SPACE
dictionary view is extended by two columns:
SHARED
and
INST_ID
. The
SHARED
column indicates whether the temporary file is local (
FOR RIM
or
FOR ALL
) or shared. The
INST_ID
column contains the instance number. For shared temporary files, there is a single row per file, and the
INST_ID
is null. For local temporary files, this column contains information about
1-16 Oracle Real Application Clusters Administration and Deployment Guide
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FREE_SPACE column).
Note:
LOCAL...FOR RIM
shows only read-only instances per file.
• In the dictionary views, such as
DBA_TABLESPACES
, Oracle distinguishes the type of the tablespace using the
SHARED
column with the following values:
–
SHARED
: for shared temporary tablespace
–
LOCAL_ON_ALL
: for local temporary tablespace on all instances
–
LOCAL_ON_RIM
: for local temporary tablespace on read-only instances
Note:
Currently, spills onto temporary tablespace for queries (such as sort and hash join spills) are automatically encrypted. This is also true for spills to local temporary tablespace.
Related Topics:
Oracle Database SQL Language Reference
Overview of Oracle RAC Architecture and Processing
At a minimum, Oracle RAC requires Oracle Clusterware software infrastructure to provide concurrent access to the same storage and the same set of data files from all nodes in the cluster, a communications protocol for enabling interprocess communication (IPC) across the nodes in the cluster, enable multiple database instances to process data as if the data resided on a logically combined, single cache, and a mechanism for monitoring and communicating the status of the nodes in the cluster.
The following sections describe these concepts in more detail:
•
Understanding Cluster-Aware Storage Solutions
•
Oracle RAC and Network Connectivity
•
Overview of Using Dynamic Database Services to Connect to Oracle Databases
•
Restricted Service Registration in Oracle RAC
•
About Oracle RAC Software Components
•
About Oracle RAC Background Processes
Understanding Cluster-Aware Storage Solutions
database. All data files, control files,
SPFILEs, and redo log files in Oracle RAC environments must reside on cluster-aware shared disks, so that all of the cluster database instances can access these storage components. Because Oracle RAC databases use a shared everything architecture,
Oracle RAC requires cluster-aware storage for all database files.
In Oracle RAC, the Oracle Database software manages disk access and is certified for use on a variety of storage architectures. It is your choice how to configure your
Introduction to Oracle RAC 1-17
Overview of Oracle RAC Architecture and Processing storage, but you must use a supported cluster-aware storage solution. Oracle Database provides the following storage options for Oracle RAC:
• Oracle Automatic Storage Management (Oracle ASM)
Oracle recommends this solution to manage your storage.
• A certified cluster file system
– Oracle recommends Oracle Automatic Storage Management Cluster File
System (Oracle ACFS).
– A third-party cluster file system on a cluster-aware volume manager that is certified for Oracle RAC. For example:
* Oracle OCFS2 (Linux, only)
* IBM GPFS (IBM AIX, only)
• Certified network file system (NFS) solution
Oracle RAC and Network Connectivity
All nodes in an Oracle RAC environment must connect to at least one Local Area
Network (LAN) (commonly referred to as the public network) to enable users and applications to access the database.
In addition to the public network, Oracle RAC requires private network connectivity
used exclusively for communication between the
s and database instances running on those nodes. This network is commonly referred to as the interconnect.
The interconnect network is a private network that connects all of the servers in the cluster. The interconnect network must use at least one switch and a Gigabit Ethernet adapter.
Note:
• Oracle supports interfaces with higher bandwidth but does not support using crossover cables with the interconnect.
• Do not use the interconnect (the private network) for user
uses the interconnect for interinstance communication.
You can configure Oracle RAC to use either the User Datagram Protocol (UDP) or
Reliable Data Socket (RDS) protocols for inter-instance communication on the interconnect. Oracle Clusterware uses the same interconnect using the UDP protocol, but cannot be configured to use RDS.
An additional network connectivity is required when using
. Network attached storage can be typical NAS devices, such as NFS
filers, or can be storage that is connected using Fibre Channel over IP, for example.
This additional network communication channel should be independent of the other communication channels used by Oracle RAC (the public and private network communication). If the storage network communication must be converged with one of the other network communication channels, then you must ensure that storagerelated communication gets first priority.
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Overview of Oracle RAC Architecture and Processing
Overview of Using Dynamic Database Services to Connect to Oracle Databases
Applications should use the Dynamic Database Services feature to connect to an
Oracle database over the public network.
Dynamic Database Services enable you to define rules and characteristics to control how users and applications connect to database instances. These characteristics include a unique name, workload balancing and failover options, and high availability characteristics.
Users can access an Oracle RAC database using a client/server configuration or through one or more middle tiers, with or without connection pooling. By default, a user connection to an Oracle RAC database is established using the TCP/IP protocol but Oracle supports other protocols. Oracle RAC database instances must be accessed through the SCAN for the cluster.
Related Topics:
Overview of Automatic Workload Management with Dynamic Database
Services represent groups of applications with common attributes, service level thresholds, and priorities.
Overview of Virtual IP Addresses
Oracle Clusterware hosts node virtual IP (VIP) addresses on the public network. Node
VIPs are VIP addresses that clients use to connect to an Oracle RAC database. A typical connect attempt from a database client to an Oracle RAC database instance can be summarized, as follows:
1.
The database client connects to SCAN (which includes a SCAN VIP on a public network), providing the SCAN listener with a valid service name.
2.
The SCAN listener then determines which database instance hosts this service and routes the client to the local or node listener on the respective node.
3.
The node listener, listening on a node VIP and a given port, retrieves the connection request and connects the client to the an instance on the local node.
If multiple public networks are used on the cluster to support client connectivity through multiple subnets, then the preceding operation is performed within a given subnet.
If a node fails, then the VIP address fails over to another node on which the VIP address can accept TCP connections, but it does not accept connections to the Oracle database. Clients that attempt to connect to a VIP address not residing on its home node receive a rapid connection refused error instead of waiting for TCP connect timeout messages. When the network on which the VIP is configured comes back online,
Oracle Clusterware fails back the VIP to its home node, where connections are accepted. Generally, VIP addresses fail over when:
• The node on which a VIP address runs fails
• All interfaces for the VIP address fail
• All interfaces for the VIP address are disconnected from the network
Oracle RAC 12c supports multiple public networks to enable access to the cluster through different subnets. Each network resource represents its own subnet and each
Introduction to Oracle RAC 1-19
Overview of Oracle RAC Architecture and Processing database service uses a particular network to access the Oracle RAC database. Each network resource is a resource managed by Oracle Clusterware, which enables the VIP behavior previously described.
SCAN is a single network name defined either in your organization's Domain Name
Server (DNS) or in the Grid Naming Service (GNS) that round robins to three IP addresses. Oracle recommends that all connections to the Oracle RAC database use the
SCAN in their client connection string. Incoming connections are load balanced across the active instances providing the requested service through the three SCAN listeners.
With SCAN, you do not have to change the client connection even if the configuration of the cluster changes (nodes added or removed). Unlike in previous releases, SCAN in Oracle RAC 12c fully supports multiple subnets, which means you can create one
SCAN for each subnet in which you want the cluster to operate.
Restricted Service Registration in Oracle RAC
The valid node checking feature provides the ability to configure and dynamically update a set of IP addresses or subnets from which registration requests are allowed by the listener.
Database instance registration with a listener succeeds only when the request originates from a valid node. The network administrator can specify a list of valid nodes, excluded nodes, or disable valid node checking. The list of valid nodes explicitly lists the nodes and subnets that can register with the database. The list of excluded nodes explicitly lists the nodes that cannot register with the database. The control of dynamic registration results in increased manageability and security of
Oracle RAC deployments.
By default, valid node checking for registration (VNCR) is enabled. In the default configuration, registration requests from all nodes within the subnet of the SCAN listener can register with the listener. Non-SCAN listeners only accept registration from instances on the local node. Remote nodes or nodes outside the subnet of the
SCAN listener must be included on the list of valid nodes by using the registration_invited_nodes_alias
parameter in the listener.ora
file or by modifying the SCAN listener using SRVCTL.
About Oracle RAC Software Components
Oracle RAC databases generally have two or more database instances that each contain memory structures and background processes. An Oracle RAC database has the same processes and memory structures as a noncluster Oracle database and additional processes and memory structures that are specific to Oracle RAC. Any one instance's database view is nearly identical to any other instance's view in the same
Oracle RAC database; the view is a single system image of the environment.
Each instance has a buffer cache in its System Global Area (SGA). Using Cache Fusion,
Oracle RAC environments logically combine each instance's buffer cache to enable the instances to process data as if the data resided on a logically combined, single cache.
Note:
• The In-Memory Transaction Manager integrates with the Cache Fusion protocol.
• The SGA size requirements for Oracle RAC are greater than the SGA requirements for noncluster Oracle databases due to Cache Fusion.
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Overview of Oracle RAC Architecture and Processing
To ensure that each Oracle RAC database instance obtains the block that it requires to satisfy a query or transaction, Oracle RAC instances use two processes, the Global
Cache Service (GCS) and the Global Enqueue Service (GES). The GCS and GES maintain records of the statuses of each data file and each cached block using a Global
Resource Directory (GRD). The GRD contents are distributed across all of the active instances, which effectively increases the size of the SGA for an Oracle RAC instance.
After one instance caches data, any other instance within the same cluster database can acquire a block image from another instance in the same database faster than by reading the block from disk. Therefore, Cache Fusion moves current blocks between instances rather than re-reading the blocks from disk. When a consistent block is needed or a changed block is required on another instance, Cache Fusion transfers the block image directly between the affected instances. Oracle RAC uses the private interconnect for interinstance communication and block transfers. The GES Monitor and the Instance Enqueue Process manage access to Cache Fusion resources and enqueue recovery processing.
Related Topics:
Oracle Database In-Memory Guide
About Oracle RAC Background Processes
The GCS and GES processes, and the GRD collaborate to enable Cache Fusion. The
Oracle RAC processes and their identifiers are as follows:
•
ACMS
: Atomic Controlfile to Memory Service (
ACMS
)
In an Oracle RAC environment, the
ACMS
per-instance process is an agent that contributes to ensuring a distributed SGA memory update is either globally committed on success or globally aborted if a failure occurs.
•
GTX0-j
: Global Transaction Process
The
GTX0-j
process provides transparent support for XA global transactions in an Oracle RAC environment. The database autotunes the number of these processes based on the workload of XA global transactions.
•
LMON
: Global Enqueue Service Monitor
The
LMON
process monitors global enqueues and resources across the cluster and performs global enqueue recovery operations.
•
LMD
: Global Enqueue Service Daemon
The
LMD
process manages incoming remote resource requests within each instance.
•
LMS
: Global Cache Service Process
The
LMS
process maintains records of the data file statuses and each cached block by recording information in a Global Resource Directory (GRD). The
LMS
process also controls the flow of messages to remote instances and manages global data block access and transmits block images between the buffer caches of different instances. This processing is part of the Cache Fusion feature.
•
LCK0
: Instance Enqueue Process
The
LCK0
process manages non-Cache Fusion resource requests such as library and row cache requests.
Introduction to Oracle RAC 1-21
Overview of Automatic Workload Management with Dynamic Database Services
•
RMSn
: Oracle RAC Management Processes (
RMSn
)
The
RMSn
processes perform manageability tasks for Oracle RAC. Tasks accomplished by an
RMSn
process include creation of resources related to Oracle
RAC when new instances are added to the clusters.
•
RSMN
: Remote Slave Monitor manages background slave process creation and communication on remote instances. These background slave processes perform tasks on behalf of a coordinating process running in another instance.
Note:
Many of the Oracle Database components that this section describes are in addition to the components that are described for noncluster Oracle databases in Oracle Database Concepts.
Related Topics:
Oracle Database Concepts
Overview of Automatic Workload Management with Dynamic Database
Services
Services represent groups of applications with common attributes, service level thresholds, and priorities.
Application functions can be divided into workloads identified by services. For example, Oracle E-Business Suite can define a service for each responsibility, such as general ledger, accounts receivable, order entry, and so on. A service can span one or more instances of an Oracle database, multiple databases in a global cluster, and a single instance can support multiple services. The number of instances that are serving the service is transparent to the application. Services provide a single system image to manage competing applications, and allow each workload to be managed as a unit.
Middle tier applications and clients select a service by specifying the service name as part of the connection in the TNS connect string. For example, data sources for Oracle
WebLogic Server are set to route to a service. Using Net Easy*Connection, this connection comprises simply the service name and network address, as follows:
user_name/password@SCAN/service_name
. Server-side work such as Oracle
Scheduler, Parallel Query, and Oracle Streams queues set the service name as part of the workload definition. For Oracle Scheduler, jobs are assigned to job classes and job classes execute within services. For Parallel Query and Parallel DML, the query coordinator connects to a service and the parallel query slaves inherit the service for the duration of the parallel execution. For Oracle Streams, streams queues are accessed using services. Work executing under a service inherits the thresholds and attributes for the service and is measured as part of the service.
Oracle Database Resource Manager binds services to consumer groups and priorities.
This allows the database to manage the services in the order of their importance. For example, the DBA can define separate services for high priority online users and lower priority internal reporting applications. Likewise, the DBA can define Gold, Silver and
Bronze services to prioritize the order in which requests are serviced for the same application. When planning the services for a system, the plan should include the priority of each service relative to the other services. In this way, Oracle Database
Resource Manager can satisfy the priority-one services first, followed by the prioritytwo services, and so on.
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Overview of Automatic Workload Management with Dynamic Database Services
When users or applications connect to a database, Oracle recommends that you use a service specified in the
CONNECT_DATA
portion of the connect string. Oracle Database automatically creates one database service when the database is created but the behavior of this service is different from that of database services that you subsequently create. To enable more flexibility in the management of a workload using the database, Oracle Database enables you to create multiple services and specify on which instances (or in which server pools) the services start. If you are interested in greater workload management flexibility, then continue reading this chapter to understand the added features that you can use with services.
Note:
The features discussed in this chapter do not work with the following default database services:
DB_NAME
,
DB_UNIQUE_NAME
,
PDB_NAME
,
SYS
$BACKGROUND
, and
SYS$USERS
. Oracle strongly recommends that you do not use these services for applications to connect to the database. You must create cluster managed services to take advantage of these features. You can only manage the services that you create. Any service that the database create automatically is managed by the database server.
Dynamic Database Services
Dynamic database services enable you to manage workload distributions to provide optimal performance for users and applications. Dynamic database services offer the following features:
•
Services
: Oracle Database provides a powerful automatic workload management facility, called services, to enable the enterprise grid vision. Services are entities that you can define in Oracle RAC databases that enable you to group database workloads, route work to the optimal instances that are assigned to offer the service, and achieve high availability for planned and unplanned actions.
•
High Availability Framework
: An Oracle RAC component that enables Oracle
Database to always maintain components in a running state.
•
Fast Application Notification (FAN)
: Provides information to Oracle RAC applications and clients about cluster state changes and Load Balancing Advisory events, such as
UP
and
DOWN
events for instances, services, or nodes. FAN has two methods for publishing events to clients, the Oracle Notification Service daemon, which is used by Java Database Connectivity (JDBC) clients including the Oracle
Application Server, and Oracle Streams Advanced Queueing, which is only used by previous releases of Oracle Call Interface (OCI) and Oracle Data Provider for .NET (ODP.NET) clients.
Note:
All clients beginning with Oracle Database 12c release 2 (12.2) use Oracle
Notification Service.
•
Transaction Guard
: A tool that provides a protocol and an API for at-most-once execution of transactions in case of unplanned outages and duplicate submissions.
•
Application Continuity
: Provides a general purpose infrastructure that replays the in-flight request when a recoverable error is received, masking many system,
Introduction to Oracle RAC 1-23
Overview of Server Pools and Policy-Managed Databases communication, and storage outages, and hardware failures. Unlike existing recovery technologies, this feature attempts to recover the transactional and nontransactional session states beneath the application, so that the outage appears to the application as a delayed execution.
•
Connection Load Balancing
: A feature of Oracle Net Services that balances incoming connections across all of the instances that provide the requested database service.
•
Load Balancing Advisory
: Provides information to applications about the current service levels that the database and its instances are providing. The load balancing advisory makes recommendations to applications about where to direct application requests to obtain the best service based on the management policy that you have defined for that service. Load balancing advisory events are published through Oracle Notification Service.
•
Automatic Workload Repository (AWR)
: Tracks service-level statistics as
Server generated alerts can be created for these metrics when they exceed or fail to meet certain thresholds.
•
Fast Connection Failover (FCF)
: This is the ability of Oracle Clients to provide rapid failover of connections by subscribing to FAN events.
•
Runtime Connection Load Balancing
: This is the ability of Oracle Clients to provide intelligent allocations of connections in the connection pool based on the current service level provided by the database instances when applications request a connection to complete some work.
•
Single Client Access Name (SCAN)
: Provides a single name to the clients connecting to Oracle RAC that does not change throughout the life of the cluster, even if you add or remove nodes from the cluster. Clients connecting with SCAN can use a simple connection string, such as a thin JDBC URL or EZConnect, and still achieve the load balancing and client connection failover.
You can deploy Oracle RAC and noncluster Oracle database environments to use dynamic database service features in many different ways. Depending on the number of nodes and your environment's complexity and objectives, your choices for optimal automatic workload management and high-availability configuration depend on several considerations that are described in this chapter.
Related Topics:
Oracle Database Administrator’s Guide
Workload Management with Dynamic Database Services
Workload management includes load balancing, enabling clients for
Oracle Real Application Clusters (Oracle RAC), distributed transaction processing, and services.
Overview of Server Pools and Policy-Managed Databases
Server pools are the basis for policy-managed databases.
You can create Oracle RAC databases, whether multinode or Oracle Real Application
Clusters One Node (Oracle RAC One Node), using the following deployment models:
• Administrator-managed deployment is based on the Oracle RAC deployment types that existed before Oracle Database 11g release 2 (11.2) and requires that you statically configure each database instance to run on a specific node in the cluster,
1-24 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Server Pools and Policy-Managed Databases and that you configure database services to run on specific instances belonging to a certain database using the preferred
and available
designation.
• Policy-managed deployment is based on server pools, where database services run within a server pool as singleton or uniform across all of the servers in the server pool. Databases are deployed in one or more server pools and the size of the server pools determine the number of database instances in the deployment.
Related Topics:
Oracle Database Quality of Service Management User's Guide
Introduction to Server Pools
Server pools logically apportion a cluster into groups of servers offering database or application services.
Server pool properties control the scalability and availability of those databases and applications. You can configure each server pool with a minimum and maximum size, which determines scalability. Oracle Clusterware manages availability between server pools, and you can further regulate availability by configuring the importance value of individual server pools.
Servers are not assigned to server pools by name but by number. Therefore, you must configure any server to run any database. If you cannot configure servers due to, for example, heterogeneous servers or storage connectivity, then you can restrict servers by using server category definitions to determine server pool membership eligibility.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Examples of Using Server Pools
This section includes the following examples of using server pools:
•
Minimum and Maximum Number of Servers
•
IMPORTANCE Attribute of Server Pools
•
Minimum and Maximum Number of Servers
Consider a four-node cluster configured into two server pools named online
and backoffice
. A database named dbsales
runs in the online
server pool offering the browse
, search
, and salescart
services. A database named dberp
runs in the backoffice
server pool and offers the inventory
and shipping
services, as
. During normal business hours the enterprise requires a minimum of two instances of the dbsales
database and one instance of the dberp database to meet normal demand.
Introduction to Oracle RAC 1-25
Overview of Server Pools and Policy-Managed Databases
Figure 1-2 Server Placement by Minimum and Maximum Limits
Online Server Pool
Min = 2, Max = 3, Imp = 5
Backoffice Server Pool
Min = 1, Max = 2, Imp = 10
Free Server Pool
Min = 0, Max = 1, Imp = 0
dbsales
browse search salescart inventory shipping
ASM Disk
Groups
ASM Disk
Groups
ASM Disk
Groups
ASM Disk
Groups
In this policy-managed deployment, the value of the
MIN_SIZE
server pool attribute for the online
server pool is 2, while the value of the
MIN_SIZE
server pool attribute for the backoffice
server pool is 1. Configured this way, Oracle Clusterware ensures that there are always two servers in the online
server pool and one server in the backoffice
server pool. Because this is a four-node cluster, there is one server left not assigned to either server pool. Where that last server gets deployed is determined by the
MAX_SIZE
server pool parameter of each server pool. If the sum of the values of the
MAX_SIZE
server pool attribute for each server pool is less than the total number of servers in the cluster, then the remaining servers stay in the Free server pool awaiting a failure of a deployed node.
If the value of
MAX_SIZE
is greater than that of
MIN_SIZE
, then the remaining server will be deployed into the server pool whose importance value is greatest, as shown in
Figure 1-2 , and fully discussed in the next section. In this case, the server is a shareable
resource that can be relocated online to join the server pool where it is required. For example, during business hours the server could be given to the online
server pool to add an instance of the dbsales
database but after hours could be relocated to the backoffice
server pool, adding a dberp
database instance. All such movements are online and instances are shut down, transactionally.
These two policy-managed databases are running only the instances that are required and they can be dynamically increased or decreased to meet demand or business requirements.
IMPORTANCE Attribute of Server Pools
The
IMPORTANCE
server pool attribute is used at cluster startup and in response to a node failure or eviction. In contrast to administrator-managed databases, you can configure server pools with different importance levels to determine which databases are started first and which databases remain online in case there is a multinode outage.
1-26 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Server Pools and Policy-Managed Databases
Consider a four-node cluster that hosts a database named dbapps
in two server pools, sales
and backoffice
. Two services, orderentry
and billing
, run in the sales
server pool, while two other services, erp
and reports
, run in the backoffice
server pool, as shown in
. By configuring the value of the
IMPORTANCE
server pool attribute of the sales
server pool higher than that of the backoffice
server pool, the services in sales
start first when the cluster starts and are always available, even if there is only one server left running after a multinode failure. The
IMPORTANCE
server pool attribute enables you to rank services and also eliminates the requirement to run a service on all nodes in a cluster to ensure that it is always available.
Figure 1-3 Server Pool Importance
Sales Server Pool
Min = 2, Max = 3, Imp = 5
Backoffice Server Pool
Min = 2, Max = 2, Imp = 10
Free Server Pool
Min = 0, Max = -1, Imp = 0 orderentry billing erp reports
ASM Disk
Groups
ASM Disk
Groups
ASM Disk
Groups
ASM Disk
Groups
Consolidation of Databases
You can use several different approaches, either discretely or combined, to consolidate
Oracle databases. Policy-managed deployments facilitate consolidation. In the case of schema consolidation, where multiple applications are being hosted in a single database separated into discrete schemas or pluggable databases (PDBs), you can use server pools to meet required capacity. Because of the dynamic scaling property of server pools, you can increase or decrease the number of database instances to meet current demand or business requirements. Since server pools also determine which services run together or separately, you can configure and maintain required affinity or isolation.
When it is not possible to use schema consolidation because of, for example, version requirements, you can host multiple databases on a single set of servers. Using policymanaged databases facilitates this database consolidation because they can share the
same server pool by making use of
, which enables you to dynamically
increase or decrease databases, both horizontally (using server pool size) and vertically (using the
CPU_COUNT
server configuration attribute) to meet demand or business policies and schedules.
Introduction to Oracle RAC 1-27
Overview of Server Pools and Policy-Managed Databases
By contrast, with administrator-managed databases, you are required to reserve capacity on each server to absorb workload failing over should a database instance or server fail. With policy-managed databases, however, you can effectively rank server pools by the business necessity of the workloads that they are running using the
MIN_SIZE
,
MAX_SIZE
, and
IMPORTANCE
server pool attributes.
When the failure of a server brings a server pool to below its configured minimum number of servers, another server will move from a less important server pool to take its place and bring the number of servers back up to the configured minimum. This eliminates the risk of cascade failures due to overloading the remaining servers and enables you to significantly reduce or even eliminate the need to reserve capacity for handling failures.
Migrating or converting to policy-managed databases also enables cluster consolidation and creates larger clusters that have greater availability and scalability because of the increased number of servers available to host and scale databases.
Because policy-managed databases do not require binding their instance names to a particular server and binding services to particular instances, the complexity of configuring and managing large clusters is greatly reduced.
An example deployment is shown in
Figure 1-4 where the previous two cluster
) are consolidated into a single cluster, making use of both database consolidation (using instance caging) and cluster consolidation (using server pools) configured so that workloads are properly sized and prioritized.
Figure 1-4 Consolidating Databases
Online Server Pool
Min = 2, Max = 3, Imp = 5
Backoffice Server Pool
Min = 2, Max = 2, Imp = 10
Free Server Pool
Min = 0, Max = -1, Imp = 0
dbsales CPU=6 browse search salescart orderentry billing inventory shipping erp reports
ASM Disk
Groups
ASM Disk
Groups
ASM Disk
Groups
ASM Disk
Groups
Related Topics:
Oracle Clusterware Administration and Deployment Guide
1-28 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Server Pools and Policy-Managed Databases
Deploying Policy-Managed Databases
When you deploy a policy-managed database you must first determine the services and their required sizing, taking into account that services cannot span server pools.
If you are going to collocate this database with other databases, then you should factor in its CPU requirements relative to the other hosted databases, and also factor in the value of its
CPU_COUNT
attribute for instance caging, so that you can size the database both vertically and horizontally in one or more server pools.
If you are going to collocate the server pools for this database with other server pools, then consider configuring the server pools to adjust the server pool sizes on a calendar or event basis to optimize meeting demand and business requirements. Once you have determined the sizes of the server pools, and configured the appropriate values for the
MIN_SIZE
and
MAX_SIZE
server pool attributes, you can then determine the relative importance of each server pool.
You, as the cluster administrator, create policy-managed database server pools using the srvctl add serverpool
command. You can modify the properties of the server pool using the srvctl modify serverpool
command in the Oracle Grid
Infrastructure home.
While it is possible to create a server pool using DBCA, Oracle recommends this only for small, single server pool deployments, because DBCA will fail if servers are already allocated to other server pools. Additionally, if the cluster is made up of servers with different capacities, such as old and new servers, Oracle recommends that you set up server category definitions defining the minimum server requirements for a server to join each server pool.
After you create the server pools, you can run DBCA from the appropriate database home. Depending on the database type and task, you will be presented with different default options. For all new Oracle RAC and Oracle RAC One Node databases, including container databases (CDBs), the Policy-Managed option is the default and the option that Oracle recommends.
If you are upgrading your database from an administrator-managed database or a database earlier than Oracle Database 11g release 2 (11.2), then you will not have the option to directly upgrade to a policy-managed database. After you upgrade, however, you can convert the database to policy managed using the srvctl modify database
command.
When you convert from an administrator-managed database to a policy-managed database, the instance names are automatically updated to include the underscore (for example: orcl1
becomes orcl_1
). The underscore is required so that the database can automatically create instances when a server pool grows in size.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Oracle Database Quality of Service Management User's Guide
Oracle Clusterware Administration and Deployment Guide
Converting an Administrator-Managed Database to a Policy-Managed Database
You can convert an administrator-managed database to a policymanaged database.
Introduction to Oracle RAC 1-29
Overview of Server Pools and Policy-Managed Databases
Managing Policy-Managed Databases
Managing a policy-managed database requires less configuration and reconfiguration steps than an administrator-managed one with respect to creation, sizing, patching, and load balancing.
Also, because any server in the server pools within the cluster can run any of the databases, you do not have to create and maintain database instance-to-node-name mappings. If, however, you want a database to use a specific instance name whenever it runs on a particular node, then you can create instance-to-node-name mappings using the srvctl modify instance -db db_unique_name -instance
inst_name -node node_name
command. This can be useful when scripts on a particular node connect to the database using a fixed
ORACLE_SID
value.
You can perform maintenance tasks such as patching by relocating servers into the
Free pool or by adjusting the server pool minimum and maximum sizes, thereby retaining required availability.
Policy-managed databases also facilitate the management of services, because they are assigned to a single server pool and run as singletons or uniform across all servers in the pool. You no longer have to create or maintain explicit preferred and available database instance lists for each service. If a server moves into a server pool because of manual relocation or a high availability event, all uniform services and their dependent database instances are automatically started. If a server hosting one or more singleton services goes down, those services will automatically be started on one or more of the remaining servers in the server pool. In the case of Oracle RAC One
Node, the corresponding database instance will also be started automatically.
Managing services relative to each other is improved by making use of the importance attribute of each server pool. Each service running in a server pool inherits the server pool's importance relative to the other server pool-hosted services in the cluster. If the minimum size of the most important server pool is greater than zero, then the services and associated database instances in that server pool are started first on cluster startup and will be the last services and database instances running, as long as there is one server running in the cluster. You can offer services not critical to the business in the least important server pool, ensuring that, should sufficient resources not be available due to demand or failures, those services will eventually be shut down and the more business-critical services remain available.
Because many management tasks may involve making changes that can affect multiple databases, services, or server pools in a consolidated environment, you can use the evaluate mode for certain SRVCTL commands to get a report of the resource impact of a command.
Consider the following example, that evaluates the effect on the system of modifying a server pool:
$ srvctl modify srvpool -l 3 -g online -eval
Service erp1 will be stopped on node test3
Service reports will be stopped on node test3
Service inventory will be stopped on node test3
Service shipping will be stopped on node test3
Database dbsales will be started on node test3
Service orderentry will be started on node test3
Service billing will be started on node test3
Service browse will be started on node test3
Service search will be started on node test3
1-30 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Server Pools and Policy-Managed Databases
Service salescart will be started on node test3
Server test3 will be moved from pool backoffice to pool online
As shown in the preceding example, modifying a server pool can result in many resource state changes. You can use a policy set through either Oracle Clusterware or
Oracle Database Quality of Service Management.
Related Topics:
SRVCTL is installed on each node in a cluster by default. To use
SRVCTL, log in to the operating system of a node and enter the SRVCTL command and its parameters in case-sensitive syntax.
Oracle Clusterware Administration and Deployment Guide
Oracle Database Quality of Service Management User's Guide
Policy-Based Cluster Management
Oracle Clusterware supports the management of a cluster configuration policy set as a native Oracle Clusterware feature.
contains one definition for each server pool that is
defined in the system. A cluster configuration policy also specifies resource placement and cluster node availability. A
cluster configuration policy set
all of the server pools that are configured in a cluster, and contains one or more configuration policies.
There is always only one configuration policy in effect at any one time. However, administrators typically create several configuration policies to reflect the different business needs and demands based on calendar dates or time of day parameters. For instance, morning hours during business days are typically when most users log in and download their email; email-related workloads are usually light at nighttime and on weekends. In such cases, you can use cluster configuration policies to define the server allocation based on the expected demand. More specifically for this example, a configuration policy that allocates more servers to OLTP workloads is in effect during workday mornings, and another configuration policy allocates more servers to batch workloads on weekends and workday evenings.
Using cluster configuration policies can also help manage clusters that comprise servers of different capabilities, such as different computer and memory sizes
(heterogeneous). To create management and availability policies for clusters comprised of heterogeneous server types, the cluster administrator can create server categories based on server attributes. These attributes can restrict which servers can be assigned to which server pools. For example, if you have some servers in a cluster that run older hardware, then you can use an attribute to specify that these servers should only be allocated to the server pools that support batch jobs and testing, instead of allocating them to the server pools that are used for online sales or other businesscritical applications.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Introduction to Oracle RAC 1-31
Overview of Oracle Database Quality of Service Management
Overview of Oracle Database Quality of Service Management
Oracle Database Quality of Service Management (Oracle Database QoS Management) is an automated, policy-based product that monitors the workload requests for an entire system.
Oracle Database QoS Management manages the resources that are shared across applications, and adjusts the system configuration to keep the applications running at the performance levels needed by your business. Oracle Database QoS Management responds gracefully to changes in system configuration and demand, thus avoiding additional oscillations in the performance levels of your applications.
Oracle Database QoS Management monitors and manages Oracle RAC database workload performance objectives by identifying bottlenecked resources impacting these objectives, and both recommending and taking actions to restore performance.
Administrator-managed deployments bind database instances to nodes but policymanaged deployments do not, so the Oracle Database QoS Management server pool size resource control is only available for the latter. All other resource management controls are available for both deployments.
Oracle Database QoS Management supports administrator-managed Oracle RAC and
Oracle RAC One Node databases with its Measure-Only, Monitor, and Management modes. This enables schema consolidation support within an administrator-managed
Oracle RAC database by adjusting the CPU shares of performance classes running in the database. Additionally, database consolidation is supported by adjusting CPU counts for databases hosted on the same physical servers.
Because administrator-managed databases do not run in server pools, the ability to expand or shrink the number of instances by changing the server pool size that is supported in policy-managed database deployments is not available for administratormanaged databases. This new deployment support is integrated into the Oracle QoS
Management pages in Oracle Enterprise Manager Cloud Control.
Related Topics:
Oracle Database Quality of Service Management User's Guide
Overview of Hang Manager
Hang Manager is an Oracle Database feature that automatically detects and resolves system hangs.
Hang Manager was first available in Oracle Database 11g release 1 (11.1) and, initially, identified system hangs and then dumped the relevant information about the hang into a trace file. In Oracle Database 12c release 2 (12.2), Hang Manager can take action on and attempt to resolve the system hang. Hang Manager also runs in both singleinstance and Oracle RAC database instances.
Note:
Hang manager does not resolve dead locks, although dead lock detection has been available in Oracle Database for several of the past releases.
Hang Manager functions, as follows:
• First detects a system hang and then analyzes the hang and verifies the cause of the hang. It then applies heuristics to decide on a course of action to resolve the hang.
1-32 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Oracle Multitenant with Oracle RAC
• Automates the tasks that used to require manual steps by a DBA to provide the trace files to My Oracle Support so that someone there could identify the source of the hang, minimizing or eliminating database and application downtime.
• Periodically scans all processes and analyzes a smaller subset of processes that are holding resources in successive scans. Hang manager ignores processes if there is nothing waiting on the resource.
• Considers cross-instance hangs, which are hangs where the holder is a database process waiting on a response from an Oracle ASM instance.
• Is aware of processes running in reader nodes instances, and checks whether any of these processes are blocking progress on Hub Nodes and takes action, if possible.
• Considers the Oracle Database Quality of Service Management settings of the holder.
• Terminates the holder process so the next process waiting on that resource can move on and prevent a hang.
• Notifies a DBA with an ORA-32701 error message in the alert log.
See Also:
Oracle Autonomous Health Framework User's Guide
Overview of Oracle Multitenant with Oracle RAC
Oracle Multitenant is an option with Oracle Database 12c that simplifies consolidation, provisioning, upgrades, and more.
It is based on an architecture that allows a multitenant container database (CDB) to hold several pluggable databases (PDBs). You can adopt an existing database as a PDB without having to change the application tier. In this architecture, Oracle RAC provides the local high availability that is required when consolidating various business-critical applications on one system.
When using PDBs with Oracle RAC, the multitenant CDB is based on Oracle RAC.
You can make each PDB available on either every instance of the Oracle RAC CDB or a subset of instances. In either case, access to and management of the PDBs are regulated using dynamic database services, which will also be used by applications to connect to the respective PDB, as they would in a single instance Oracle database using Oracle Net Services for connectivity.
You can isolate PDBs to prevent certain operations from being performed on or within a particular PDB that may interfere with other PDBs sharing the same Oracle RAC database or database instance. PDB isolation allows for a higher degree of consolidation using Oracle Multitenant.
If you create an Oracle RAC database as a CDB and plug one or more PDBs into the
CDB, then, by default, a PDB is not started automatically on any instance of the Oracle
RAC CDB. With the first dynamic database service assigned to the PDB (other than the default database service which has the same name as the database name), the PDB is made available on those instances on which the service runs.
Whether a PDB is available on more than one instance of an Oracle RAC CDB, the
CDB is typically managed by the services running on the PDB. You can manually enable PDB access on each instance of an Oracle RAC CDB by starting the PDB manually on that instance.
Introduction to Oracle RAC 1-33
Overview of Database In-Memory and Oracle RAC
Overview of Database In-Memory and Oracle RAC
Each node in an Oracle RAC environment has its own In-Memory (IM) column store.
By default, populated objects are distributed across all IM column stores in the cluster.
Each node in an Oracle RAC environment has its own In-Memory (IM) column store.
Oracle recommends that you equally size the IM column stores on each Oracle RAC node. For any Oracle RAC node that does not require an IM column store, set the
INMEMORY_SIZE
parameter to 0.
It is possible to have completely different objects populated on every node, or to have larger objects distributed across all of the IM column stores in the cluster. It is also possible to have the same objects appear in the IM column store on every node (on engineered systems, only). The distribution of objects across the IM column stores in a cluster is controlled by two additional sub-clauses to the
INMEMORY
attribute;
DISTRIBUTE
and
DUPLICATE
.
In an Oracle RAC environment, an object that only has the
INMEMORY
attribute specified on it is automatically distributed across the IM column stores in the cluster.
The
DISTRIBUTE
clause can be used to specify how an object is distributed across the cluster. By default, the type of partitioning used (if any) determines how the object is distributed. If the object is not partitioned it is distributed by rowid range.
Alternatively, you can specify the
DISTRIBUTE
clause to over-ride the default behavior.
On an Engineered System, it is possible to duplicate or mirror objects populated in memory across the IM column store in the cluster. This provides the highest level of redundancy. The
DUPLICATE
clause is used to control how an object should be duplicated across the IM column stores in the cluster. If you specify just
DUPLICATE
, then one mirrored copy of the data is distributed across the IM column stores in the cluster. If you want to duplicate the entire object in each IM column store in the cluster, then specify
DUPLICATE ALL
.
Note:
When you deploy Oracle RAC on a non-Engineered System, the
DUPLICATE clause is treated as
NO DUPLICATE
.
Related Topics:
Oracle Database In-Memory Guide
Overview of Managing Oracle RAC Environments
This section describes the following Oracle RAC environment management topics:
•
About Designing and Deploying Oracle RAC Environments
•
About Administrative Tools for Oracle RAC Environments
•
About Monitoring Oracle RAC Environments
•
About Evaluating Performance in Oracle RAC Environments
1-34 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Managing Oracle RAC Environments
About Designing and Deploying Oracle RAC Environments
Any enterprise that is designing and implementing a high availability strategy with
Oracle RAC must begin by performing a thorough analysis of the business drivers that require high availability.
An analysis of business requirements for high availability combined with an understanding of the level of investment required to implement different high availability solutions enables the development of a high availability architecture that achieves both business and technical objectives.
Related Topics:
Design and Deployment Techniques
Oracle Database High Availability Overview
See Also:
For help choosing and implementing the architecture that best fits your availability requirements:
• "Design and Deployment Techniques" provides a high-level overview you can use to evaluate the high availability requirements of your business.
•
Oracle Database High Availability Overview
describes how to select the most suitable architecture for your organization, describes several high availability architectures, and provides guidelines for choosing the one that best meets your requirements, and also provides information about the Oracle Maximum Availability Architecture
About Administrative Tools for Oracle RAC Environments
You administer a cluster database as a single-system image using the Server Control
Utility (SRVCTL), Oracle Enterprise Manager, SQL*Plus, and other utilities.
•
Server Control Utility (SRVCTL)
: SRVCTL is a command-line interface that you can use to manage an Oracle RAC database from a single point. You can use
SRVCTL to start and stop the database and instances and to delete or move instances and services. You can also use SRVCTL to manage configuration information, Oracle Real Application Clusters One Node (Oracle RAC One Node),
Oracle Clusterware, and Oracle ASM.
•
Rapid Home Provisioning
: Use Rapid Home Provisioning to patch, upgrade, and provision Oracle RAC databases.
•
Oracle Enterprise Manager
: Oracle Enterprise Manager Cloud Control GUI interface for managing both noncluster database and Oracle RAC database environments. Oracle recommends that you use Oracle Enterprise Manager to perform administrative tasks whenever feasible.
You can use Oracle Enterprise Manager Cloud Control to also manage Oracle
RAC One Node databases.
•
SQL*Plus
: SQL*Plus commands operate on the current instance. The current instance can be either the local default instance on which you initiated your
Introduction to Oracle RAC 1-35
Overview of Managing Oracle RAC Environments
SQL*Plus session, or it can be a remote instance to which you connect with Oracle
Net Services.
•
Cluster Verification Utility (CVU)
: CVU is a command-line tool that you can use to verify a range of cluster and Oracle RAC components, such as shared storage devices, networking configurations, system requirements, and Oracle
Clusterware, in addition to operating system groups and users. You can use CVU for preinstallation checks and for postinstallation checks of your cluster environment. CVU is especially useful during preinstallation and during installation of Oracle Clusterware and Oracle RAC components. Oracle Universal
Installer runs CVU after installing Oracle Clusterware and Oracle Database to verify your environment.
Install and use CVU before you install Oracle RAC to ensure that your configuration meets the minimum Oracle RAC installation requirements. Also, use CVU for verifying the completion of ongoing administrative tasks, such as node addition and node deletion.
•
DBCA
: The recommended utility for creating and initially configuring Oracle
RAC, Oracle RAC One Node, and Oracle noncluster databases.
•
NETCA
: Configures the network for your Oracle RAC environment.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Administering Database Instances and Cluster Databases
Monitoring Oracle RAC and Oracle Clusterware
Server Control Utility Reference
Oracle Clusterware Administration and Deployment Guide
Oracle Database Net Services Administrator's Guide
See Also:
• "Administering Database Instances and Cluster Databases" for an introduction to Oracle RAC administration using SRVCTL, Oracle
Enterprise Manager, and SQL*Plus
• "Monitoring Oracle RAC and Oracle Clusterware"
• "Server Control Utility Reference" for SRVCTL reference information
•
Oracle Clusterware Administration and Deployment Guide
for information about the Cluster Verification Utility (CVU), in addition to other Oracle
Clusterware tools, such as the OIFCFG tool for allocating and deallocating network interfaces and the
OCRCONFIG
command-line tool for managing
OCR
•
Oracle Database Net Services Administrator's Guide
for more information about NETCA
1-36 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Managing Oracle RAC Environments
About Monitoring Oracle RAC Environments
Web-based Oracle Enterprise Manager Cloud Control enables you to monitor an
Oracle RAC database.
Oracle Enterprise Manager Cloud Control is a central point of control for the Oracle environment that you access by way of a graphical user interface (GUI). See
"Monitoring Oracle RAC and Oracle Clusterware" and Oracle Database 2 Day + Real
Application Clusters Guide
for detailed information about using Oracle Enterprise
Manager to monitor Oracle RAC environments.
Also, note the following recommendations about monitoring Oracle RAC environments:
• Use Oracle Enterprise Manager Cloud Control to initiate cluster database management tasks.
• Use Oracle Enterprise Manager Cloud Control to administer multiple or individual Oracle RAC databases.
• Use the global views (
GV$
views), which are based on
V$
views. The catclustdb.sql
script creates the
GV$
views. Run this script if you do not create your database with DBCA. Otherwise, DBCA runs this script for you.
For almost every
V$
view, there is a corresponding global
GV$
view. In addition to the
V$
information, each
GV$
view contains an extra column named
INST_ID
, which displays the instance number from which the associated
V$
view information was obtained.
• Use the sophisticated management and monitoring features of the Oracle
Database Diagnostic and Tuning packs within Oracle Enterprise Manager that include the Automatic Database Diagnostic Monitor (ADDM) and Automatic
Workload Repository (AWR).
Note:
Although Statspack is available for backward compatibility, Statspack provides reporting only. You must run Statspack at level 7 to collect statistics related to block contention and segment block waits.
Related Topics:
Monitoring Oracle RAC and Oracle Clusterware
Oracle Database 2 Day + Real Application Clusters Guide
Oracle Database Performance Tuning Guide
See Also:
Oracle Database Performance Tuning Guide
for descriptions of the Oracle
Database automatic features for performance diagnosing and tuning, including ADDM
Introduction to Oracle RAC 1-37
Overview of Managing Oracle RAC Environments
About Evaluating Performance in Oracle RAC Environments
You do not need to perform special tuning for Oracle RAC; Oracle RAC scales without special configuration changes. If your application performs well on a noncluster
Oracle database, then it will perform well in an Oracle RAC environment. Many of the tuning tasks that you would perform on a noncluster Oracle database can also improve Oracle RAC database performance. This is especially true if your environment requires scalability across a greater number of CPUs.
Some of the performance features specific to Oracle RAC include:
• Dynamic resource allocation
– Oracle Database dynamically allocates Cache Fusion resources as needed
– The dynamic mastering of resources improves performance by keeping resources local to data blocks
• Cache Fusion enables a simplified tuning methodology
– You do not have to tune any parameters for Cache Fusion
– No application-level tuning is necessary
– You can use a bottom-up tuning approach with virtually no effect on your existing applications
• More detailed performance statistics
– More views for Oracle RAC performance monitoring
– Oracle RAC-specific performance views in Oracle Enterprise Manager
1-38 Oracle Real Application Clusters Administration and Deployment Guide
2
Administering Storage in Oracle RAC
Oracle recommends Oracle Automatic Storage Management (Oracle ASM) as a storage management solution that provides an alternative to conventional volume managers, file systems, and raw devices.
for Oracle database files that
supports single-instance Oracle Database and Oracle Real Application Clusters (Oracle
RAC) configurations.
Oracle ASM uses disk groups to store data files; an Oracle ASM disk group is a collection of disks that Oracle ASM manages as a unit. Within a disk group, Oracle
ASM exposes a file system interface for Oracle database files. The content of files that are stored in a disk group is evenly distributed to eliminate hot spots and to provide uniform performance across the disks. The performance is comparable to the performance of raw devices.
You can add or remove disks from a disk group while a database continues to access files from the disk group. When you add or remove disks from a disk group, Oracle
ASM automatically redistributes the file contents and eliminates the need for downtime when redistributing the content.
The Oracle ASM volume manager functionality provides flexible server-based mirroring options. The Oracle ASM normal and high redundancy disk groups enable two-way and three-way mirroring respectively. You can use external redundancy to enable a Redundant Array of Independent Disks (RAID) storage subsystem to perform the mirroring protection function.
Oracle ASM also uses the Oracle Managed Files feature to simplify database file management. Oracle Managed Files automatically creates files in designated locations.
Oracle Managed Files also names files and removes them while relinquishing space when tablespaces or files are deleted.
Oracle ASM reduces the administrative overhead for managing database storage by consolidating data storage into a small number of disk groups. The smaller number of disk groups consolidates the storage for multiple databases and dprovides for improved I/O performance.
Oracle ASM files can coexist with other storage management options such as raw disks and third-party file systems. This capability simplifies the integration of Oracle
ASM into pre-existing environments.
Oracle ASM has easy to use management interfaces such as SQL*Plus, the Oracle ASM
Command Line Utility (ASMCMD) command-line interface, and Oracle ASM
Configuration Assistant (ASMCA).
This chapter includes the following topics:
•
Overview of Storage Management for Oracle RAC
•
Data File Access in Oracle RAC
Administering Storage in Oracle RAC 2-1
Overview of Storage Management for Oracle RAC
•
•
Redo Log File Storage in Oracle RAC
•
Automatic Undo Management in Oracle RAC
•
Oracle Automatic Storage Management with Oracle RAC
Related Topics:
Oracle Automatic Storage Management Administrator's Guide
Oracle Automatic Storage Management Administrator's Guide
Overview of Storage Management for Oracle RAC
All data files (including an undo tablespace for each instance) and redo log files (at least two for each instance) for an Oracle RAC database must reside on shared storage.
Oracle recommends that you use Oracle ASM to store these files in an Oracle ASM disk group.
Oracle supports alternative ways of using shared storage, such as certified
s. In addition, Oracle recommends that you use one shared server parameter file (SPFILE) with instance-specific entries. Oracle RAC 12c allows storing shared password files in Oracle ASM and storing Oracle Database files on Oracle Automatic
Storage Management Cluster File System (Oracle ACFS).
Note:
Oracle Database and related technologies, such as Oracle Clusterware, no longer support the use of raw (block) storage devices. You must move files to
Oracle ASM before upgrading to Oracle Clusterware 12c.
Unless otherwise noted, Oracle Database storage features such as Oracle ASM, Oracle
Managed Files, automatic segment-space management, and so on, function the same in Oracle RAC environments as they do in noncluster Oracle database environments.
Note:
To create an Oracle RAC database using Oracle Database Standard Edition, you must use Oracle ASM for your database storage.
Related Topics:
Oracle Database 2 Day DBA
Oracle Automatic Storage Management Administrator's Guide
Oracle Database Administrator’s Guide
Data File Access in Oracle RAC
All Oracle RAC instances must be able to access all data files. If a data file must be recovered when the database is opened, then the first Oracle RAC instance to start is the instance that performs the recovery and verifies access to the file. As other
2-2 Oracle Real Application Clusters Administration and Deployment Guide
NFS Server for Storage instances start, they also verify their access to the data files. Similarly, when you add a tablespace or data file or bring a tablespace or data file online, all instances verify access to the file or files.
If you add a data file to a disk that other instances cannot access, then verification fails.
Verification also fails if instances access different copies of the same data file. If verification fails for any instance, then diagnose and fix the problem. Then run the
ALTER SYSTEM CHECK DATAFILES
statement on each instance to verify data file access.
NFS Server for Storage
An Oracle database can serve as a network file system (NFS) server. The database responds to NFS requests from any NFS client and stores both the files and their metadata within the database.
Files associated with a primary database, such as SQL scripts, can be automatically replicated on a standby database. You can also store unstructured data, such as emails, on the database.
You can create or destroy an Oracle file system and access it though the NFS server using the procedures documented in Oracle Database SecureFiles and Large Objects
Developer's Guide
.
Related Topics:
Oracle Database SecureFiles and Large Objects Developer's Guide
Oracle Database PL/SQL Packages and Types Reference
Oracle Database Reference
Redo Log File Storage in Oracle RAC
In an Oracle RAC database, each instance must have at least two groups of redo log files. You must allocate the redo log groups before enabling a new instance with the
ALTER DATABASE ENABLE INSTANCE instance_name
command. When you use
DBCA to create the database, DBCA allocates redo log files to instances, as required, automatically. You can change the number of redo log groups and the size of the redo log files as required either during the initial database creation or as a post-creation step.
When the current group fills, an instance begins writing to the next log file group. If your database is in
ARCHIVELOG
mode, then each instance must save filled online log groups as archived redo log files that are tracked in the control file. During database recovery, all enabled instances are checked to see if recovery is needed. If you remove an instance from your Oracle RAC database, then you should disable the instance's thread of redo so that Oracle does not have to check the thread during database recovery.
Redo log management must be considered when the number of instances for a particular production Oracle RAC database changes. For example, if you increase the cardinality of a server pool for a policy-managed database and a new server is allocated to the server pool, then Oracle starts an instance on the new server. As soon as the database instance on the new server starts, it will require a set of redo log groups. Using Oracle Managed Files based on an Oracle ASM disk group, allocation of the required redo log thread and respective files is performed automatically. You should create redo log groups only if you use administrator-managed databases.
Administering Storage in Oracle RAC 2-3
Automatic Undo Management in Oracle RAC
For administrator-managed databases, each instance has its own online redo log groups. Create these redo log groups and establish group members. To add a redo log group to a specific instance, specify the
INSTANCE
clause in the
ALTER DATABASE
ADD LOGFILE
statement. If you do not specify the instance when adding the redo log group, then the redo log group is added to the instance to which you are currently connected.
Each instance must have at least two groups of redo log files. You must allocate the redo log groups before enabling a new instance with the
ALTER DATABASE ENABLE
INSTANCE
instance_name
command. When the current group fills, an instance begins writing to the next log file group. If your database is in
ARCHIVELOG
mode, then each instance must save filled online log groups as archived redo log files that are tracked in the control file.
During database recovery, all enabled instances are checked to see if recovery is needed. If you remove an instance from your Oracle RAC database, then you should disable the instance's thread of redo so that Oracle does not have to check the thread during database recovery.
Related Topics:
About Designing and Deploying Oracle RAC Environments
Any enterprise that is designing and implementing a high availability strategy with Oracle RAC must begin by performing a thorough analysis of the business drivers that require high availability.
Oracle Database Administrator’s Guide
Oracle Database SQL Language Reference
Automatic Undo Management in Oracle RAC
Oracle Database automatically manages undo segments within a specific undo tablespace that is assigned to an instance. Instances can always read all undo blocks
environment for consistent read purposes. Also, any instance can update any undo tablespace during transaction recovery, if that undo tablespace is not currently used by another instance for undo generation or transaction recovery.
You assign undo tablespaces in your Oracle RAC administrator-managed database by specifying a different value for the
UNDO_TABLESPACE
parameter for each instance in your SPFILE or individual PFILEs. For policy-managed databases, Oracle automatically allocates the undo tablespace when the instance starts if you have
Oracle Managed Files enabled. You cannot simultaneously use automatic undo management and manual undo management in an Oracle RAC database. In other words, all instances of an Oracle RAC database must operate in the same undo mode.
Related Topics:
Setting SPFILE Parameter Values for Oracle RAC
Oracle Database Administrator’s Guide
Oracle Automatic Storage Management with Oracle RAC
Oracle ASM automatically maximizes I/O performance by managing the storage configuration across the disks that Oracle ASM manages.
Oracle ASM does this by evenly distributing the database files across all of the available storage assigned to the disk groups within Oracle ASM. Oracle ASM
2-4 Oracle Real Application Clusters Administration and Deployment Guide
Oracle Automatic Storage Management with Oracle RAC allocates your total disk space requirements into uniformly sized units across all disks in a disk group. Oracle ASM can also automatically mirror files to prevent data loss.
Because of these features, Oracle ASM also significantly reduces your administrative overhead.
Oracle ASM instances are created on each node where you install Oracle Clusterware.
Each Oracle ASM instance has either an SPFILE or PFILE type parameter file. Oracle recommends that you back up the parameter files and the TNS entries for nondefault
Oracle Net listeners.
To use Oracle ASM with Oracle RAC, select Oracle ASM as your storage option when you create your database with the Database Configuration Assistant (DBCA). As in noncluster Oracle databases, using Oracle ASM with Oracle RAC does not require I/O tuning.
The following topics describe Oracle ASM and Oracle ASM administration, as follows:
•
Storage Management in Oracle RAC
•
Modifying Disk Group Configurations for Oracle ASM
•
Oracle ASM Disk Group Management
•
Configuring Preferred Mirror Read Disks in Extended Distance Clusters
•
Converting Nonclustered Oracle ASM to Clustered Oracle ASM
•
Administering Oracle ASM Instances with SRVCTL in Oracle RAC
Related Topics:
Oracle Automatic Storage Management Administrator's Guide
Storage Management in Oracle RAC
You can create Oracle ASM disk groups and configure mirroring for Oracle ASM disk groups using the Oracle ASM configuration assistant (ASMCA).
Alternatively, you can use Oracle Enterprise Manager to administer Oracle ASM disk groups after you have discovered the respective servers with Oracle Enterprise
Manager.
The Oracle tools that you use to manage Oracle ASM, including ASMCA, Oracle
Enterprise Manager, and the silent mode install and upgrade commands, include options to manage Oracle ASM instances and disk groups.
You can use the Cluster Verification Utility (CVU) to verify the integrity of Oracle
ASM across the
. Typically, this check ensures that the Oracle ASM instances on
all nodes run from the same Oracle home and, if asmlib
exists, that it is a valid version and has valid ownership. Run the following command to perform this check: cluvfy comp asm [-n node_list] [-verbose]
Replace
node_list
with a comma-delimited list of node names on which the check is to be performed. Specify all
to check all nodes in the cluster.
Use the cluvfy comp ssa
command to locate shared storage.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Administering Storage in Oracle RAC 2-5
Oracle Automatic Storage Management with Oracle RAC
Modifying Disk Group Configurations for Oracle ASM
When you create a disk group for a cluster or add new disks to an existing clustered disk group, prepare the underlying physical storage on shared disks and give the
Oracle user permission to read and write to the disk.
The shared disk requirement is the only substantial difference between using Oracle
ASM with an Oracle RAC database compared to using it with a noncluster Oracle database. Oracle ASM automatically redistributes the data files after you add or delete a disk or disk group.
In a cluster, each Oracle ASM instance manages its node's metadata updates to the disk groups. In addition, each Oracle ASM instance coordinates disk group metadata with other nodes in the cluster. As with noncluster Oracle databases, you can use
Oracle Enterprise Manager, ASMCA, SQL*Plus, and the Server Control Utility
(SRVCTL) to administer disk groups for Oracle ASM that are used by Oracle RAC.
Oracle Automatic Storage Management Administrator's Guide
explains how to use
SQL*Plus to administer Oracle ASM instances. Subsequent sections describe how to use the other tools.
Note:
When you start ASMCA, if there is not an Oracle ASM instance, then the utility prompts you to create one.
Related Topics:
Oracle Automatic Storage Management Administrator's Guide
Oracle ASM Disk Group Management
To use Oracle ASM, you must first create disk groups with ASMCA before creating a database with DBCA.
You can also use the disk group management commands to create and manage an
Oracle ASM instance and its associated disk groups independently of creating a database. You can use Oracle Enterprise Manager or ASMCA to add disks to a disk group, to mount a disk group or to mount all of the disk groups, or to create Oracle
ASM instances. Additionally, you can use Oracle Enterprise Manager to dismount and drop disk groups or to delete Oracle ASM instances.
Oracle ASM instances are created when you install Oracle Clusterware. To create an
Oracle ASM disk group, run ASMCA from the
Grid_home/bin
directory. You can also use the Oracle ASM Disk Groups page in ASMCA for Oracle ASM management.
That is, you can configure Oracle ASM storage separately from database creation. For example, from the ASM Disk Groups page, you can create disk groups, add disks to existing disk groups, or mount disk groups that are not currently mounted.
When you start ASMCA, if the Oracle ASM instance has not been created, then
ASMCA prompts you to create the instance. ASMCA prompts you for the sysasm password and the
ASMSNMP
password.
Related Topics:
Oracle Automatic Storage Management Administrator's Guide
2-6 Oracle Real Application Clusters Administration and Deployment Guide
Oracle Automatic Storage Management with Oracle RAC
Configuring Preferred Mirror Read Disks in Extended Distance Clusters
When you configure Oracle ASM
s, it may be more efficient for a node to
read from an extent that is closest to the node, even if that extent is a secondary extent.
You can configure Oracle ASM to read from a secondary extent if that extent is closer to the node instead of Oracle ASM reading from the primary copy which might be farther from the node. Using preferred read failure groups is most beneficial in an
.
To configure this feature, set the
ASM_PREFERRED_READ_FAILURE_GROUPS initialization parameter to specify a list of failure group names as preferred read disks.
Oracle recommends that you configure at least one mirrored extent copy from a disk that is local to a node in an extended cluster. However, a failure group that is preferred for one instance might be remote to another instance in the same Oracle
RAC database. The parameter setting for preferred read failure groups is instance specific.
Related Topics:
Oracle Automatic Storage Management Administrator's Guide
Oracle Database Reference
Converting Nonclustered Oracle ASM to Clustered Oracle ASM
When installing Oracle Grid Infrastructure, any nonclustered Oracle ASM instances are automatically converted to clustered Oracle ASM.
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
Oracle Automatic Storage Management Administrator's Guide
Administering Oracle ASM Instances with SRVCTL in Oracle RAC
You can use the Server Control Utility (SRVCTL) to add or remove an Oracle ASM instance.
To issue SRVCTL commands to manage Oracle ASM, log in as the operating system user that owns the Oracle Grid Infrastructure home and issue the SRVCTL commands from the bin directory of the Oracle Grid Infrastructure home.
Use the following syntax to add an Oracle ASM instance: srvctl add asm
Use the following syntax to remove an Oracle ASM instance: srvctl remove asm [-force]
You can also use SRVCTL to start, stop, and obtain the status of an Oracle ASM instance as in the following examples.
Use the following syntax to start an Oracle ASM instance: srvctl start asm [-node node_name] [-startoption start_options]
Use the following syntax to stop an Oracle ASM instance:
Administering Storage in Oracle RAC 2-7
Oracle Automatic Storage Management with Oracle RAC srvctl stop asm [-node node_name] [-stopoption stop_options]
Use the following syntax to show the configuration of an Oracle ASM instance: srvctl config asm -node node_name
Use the following syntax to display the state of an Oracle ASM instance: srvctl status asm [-node node_name]
Related Topics:
Server Control Utility Reference
Oracle Automatic Storage Management Administrator's Guide
2-8 Oracle Real Application Clusters Administration and Deployment Guide
3
Administering Database Instances and
Cluster Databases
This chapter describes how to administer Oracle Real Application Clusters (Oracle
RAC) databases and database instances.
The topics in this chapter include:
•
Overview of Oracle RAC Database Administration
•
Starting and Stopping Instances and Oracle RAC Databases
•
Starting and Stopping PDBs in Oracle RAC
•
Verifying That Instances are Running
•
Terminating Sessions On a Specific Cluster Instance
•
Overview of Initialization Parameter Files in Oracle RAC
•
Initialization Parameter Use in Oracle RAC
•
Converting an Administrator-Managed Database to a Policy-Managed Database
•
Managing Memory Pressure for Database Servers
•
Quiescing Oracle RAC Databases
•
Administering Multiple Cluster Interconnects on Linux and UNIX Platforms
•
Customizing How Oracle Clusterware Manages Oracle RAC Databases
•
Advanced Oracle Enterprise Manager Administration
See Also:
The Oracle Enterprise Manager Cloud Control online help for more information about Oracle Enterprise Manager Cloud Control
Overview of Oracle RAC Database Administration
Oracle RAC database administration requires certain privileges and involves either a policy-managed or administrator-managed deployment model.
Required Privileges for Oracle RAC Database Administration
To increase security and further separate administrative duties, Oracle RAC database administrators manage Oracle RAC databases with the SYSRAC administrative privilege, and no longer require the SYSDBA administrative privilege. The SYSRAC
Administering Database Instances and Cluster Databases 3-1
Overview of Oracle RAC Database Administration administrative privilege is the default mode of connecting to the database by the
Oracle Clusterware agent on behalf of Oracle RAC utilities, such as SRVCTL, meaning that no SYSDBA connections to the database are necessary for everyday administration of Oracle RAC database clusters.
Oracle RAC Database Depolyment Models
Oracle RAC databases support two different management styles and deployment models:
• Administrator-managed deployment is based on the Oracle RAC deployment types that existed before Oracle Database 11g release 2 (11.2) and requires that you statically configure each database instance to run on a specific node in the cluster, and that you configure database services to run on specific instances belonging to a certain database using the preferred
and available
designation.
• Policy-managed deployment is based on server pools, where database services run within a server pool as singleton or uniform across all of the servers in the server pool. Databases are deployed in one or more server pools and the size of the server pools determine the number of database instances in the deployment.
You can manage databases with either the administrator-managed or policy-managed deployment model using the same commands or methods (such as DBCA or Oracle
Enterprise Manager). All commands and utilities maintain backward compatibility to support the management of Oracle databases that only support administrator-based management (Oracle databases before Oracle Database 11g release 2 (11.2)).
In general, a database is defined as a resource in Oracle Clusterware. The database resource is automatically created when you create your database with DBCA or provision a database using Rapid Home Provisioning, or you can manually create the database resource by adding your database with SRVCTL. The database resource contains the Oracle home, the SPFILE, one or more server pools, and one or more
Oracle ASM disk groups required for the database to start. You can specify the Oracle
ASM disk groups using either the srvctl add database
or srvctl modify database
commands, or, when the database opens a data file on a disk group that is not on this list, the disk group gets added to the list.
The database resource also has a weak start dependency on the listener type, which means that the resource tries to start all listeners for the node when the database instance starts. Oracle Clusterware tries to start listeners on the node where the database instance starts. Starting the listeners in turn starts the VIP for the node.
When you review the database resource for an administrator-managed database, you see a server pool defined with the same name as the Oracle database. This server pool is part of a special Oracle-defined server pool called Generic. Oracle RAC manages the
Generic server pool to support administrator-managed databases. When you add or remove an administrator-managed database using either SRVCTL or DBCA, Oracle
RAC creates or removes the server pools that are members of Generic. You cannot use
SRVCTL or CRSCTL commands to modify the Generic server pool.
Use
s to simplify management of dynamic systems. Policy
management allows clusters and databases to expand or shrink as requirements change. If you use policy-managed databases, then you must install the Oracle home software on every node in your cluster. Policy-managed databases must use Oracle
Database 11g release 2 (11.2) or higher software and cannot coexist on the same servers as administrator-managed databases.
3-2 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Oracle RAC Database Administration
Note:
You cannot run more than one instance of the same database on the same node.
A policy-managed database is defined by
, which is the number of database instances you want running during normal operations. A policy-managed database runs in one or more database server pools that the cluster administrator creates in the cluster, and it can run on different servers at different times. Every server pool of a policy-managed database should have at least one database service. A database instance starts on a server that is in the server pools defined for the database. If you are using Oracle Automatic Storage Management (Oracle ASM) with Oracle Managed
Files for your database storage, then, when an instance starts and there is no redo thread available, Oracle RAC automatically enables one and creates the required redo log files and undo tablespace. Clients can connect to a policy-managed database using the same SCAN-based connect string no matter which servers they happen to be running on at the time.
Policy-managed databases are named
db_unique_name_cardinality
, where
cardinality
is the cardinality ID of the server in the server pool. Use the srvctl status database -sid
command to retrieve the instance name on the local node.
You can also create a fixed mapping of nodes-to-instance name using the srvctl modify instance
command.
Using the Same Cluster for Administrator-Managed and Policy-Managed
Databases
If you want to create an administrator-managed database on a cluster that already hosts policy-managed databases, then you must carefully select the nodes for the administrator-managed database. This is because the nodes that you select for an administrator-managed database that are in policy-managed server pools will be moved into the Generic server pool as part of this process.
If you select nodes that already run other policy-managed database instances, then
DBCA prompts you with a message that lists the instances and services that will be shut down when DBCA creates the administrator-managed database. If you select the
Yes
button on the dialog box when DBCA asks "Do you want to continue?", then your policy-managed database instances and services will be shut down because of the administrator-managed database creation process.
Note:
This is also true if you use the srvctl add instance
command, which returns a similar error message indicating that the databases would be shut down. If you also use the force option (
-f
) with the srvctl add instance command, then this is the same as choosing Yes on the DBCA dialog. Doing this shuts down any policy-managed databases that are running on the node before moving the node into the Generic server pool.
Related Topics:
Oracle Database Security Guide
Oracle Clusterware Administration and Deployment Guide
Administering Database Instances and Cluster Databases 3-3
Overview of Oracle RAC Database Administration
Converting an Administrator-Managed Database to a Policy-Managed Database
You can convert an administrator-managed database to a policymanaged database.
Tools for Administering Oracle RAC
The following sections introduce Oracle RAC administration using the three tools that you commonly use to manage Oracle RAC databases and instances: the SRVCTL utility, Oracle Enterprise Manager, and SQL*Plus. In many cases, you use these tools the same way to manage Oracle RAC environments as you would use them manage noncluster Oracle databases:
•
Administering Oracle RAC with SRVCTL
•
Administering Oracle RAC with Oracle Enterprise Manager
•
Administering Oracle RAC with SQL*Plus
Administering Oracle RAC with SRVCTL
The Server Control Utility (SRVCTL) is a command-line interface that you can use to manage Oracle Databases in a centralized manner.
Oracle made centralized, SRVCTL-based database management available in Oracle
Database 11g release 2 (11.2) for single-instance Oracle Databases, using Oracle ASM in the Oracle Grid Infrastructure, for both a noncluster environment and Oracle RAC databases, based on Oracle Grid Infrastructure for a cluster. This enables homogeneous management of all Oracle Database types using SRVCTL. You can use
SRVCTL to start and stop the database and instances, and to delete or move instances and services. You can also use SRVCTL to add services and manage configuration information, in addition to other resources in the cluster.
When you use SRVCTL to perform configuration operations on your cluster, SRVCTL stores configuration data in the Oracle Cluster Registry (OCR) in a cluster or Oracle
Local Registry (OLR) in Oracle Restart environments. SRVCTL performs other operations, such as starting and stopping instances, by configuring and managing
Oracle Clusterware resources, which define agents that perform database startup and shutdown operations using Oracle Call Interface APIs.
Note:
If you require your database (or database instance) to start using certain environment variables, then use the srvctl setenv
command to set those variables for the database profile that is maintained for the database using
SRVCTL. You do not need to set the
ORACLE_HOME
and
ORACLE_SID environment variables, because SRVCTL maintains and sets those parameters, automatically.
Related Topics:
Server Control Utility Reference
Administering Oracle RAC with Oracle Enterprise Manager
Oracle Enterprise Manager provides a central point of control for the Oracle RAC environment, allowing you to perform administrative tasks simultaneously on multiple cluster databases.
3-4 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Oracle RAC Database Administration
Based on the Oracle Enterprise Manager Cloud Control (Grid Control in Oracle
Enterprise Manager 11g) graphical user interface (GUI), you can manage both nonclustered and Oracle RAC environments.
In Oracle Enterprise Manager, Oracle RAC-specific administrative tasks generally
focus on two levels: tasks that affect an entire
specific instances. For example, you can use Oracle Enterprise Manager to start, stop, and monitor databases, cluster database instances, and their listeners, and to schedule jobs or set up alert thresholds for metrics. Or you can perform instance-specific commands such as setting parameters or creating resource plans. You can also use
Oracle Enterprise Manager to manage schemas, security, and cluster database storage features.
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
Advanced Oracle Enterprise Manager Administration
You can install, configure, and monitor an Oracle RAC database from a single location using Oracle Enterprise Manager Cloud Control.
Administering Oracle RAC with SQL*Plus
Unlike SRVCTL or Oracle Enterprise Manager, SQL*Plus is an instance-oriented management tool.
SQL*Plus commands operate on the current instance. The current instance can be either the local default instance on which you initiated your SQL*Plus session, or it can be a remote instance to which you connect with Oracle Net Services. For an Oracle
RAC environment that runs multiple instances on one database at the same time, this implies that you need to consider the extent to which SQL*Plus can operate on this instance. Due to those restrictions, you should not use SQL*Plus to manage policymanaged databases.
For example, when using pluggable databases (PDBs)—regardless of whether those databases are managed in an administrator-managed or a policy-managed style—you must consider that any alteration performed on the PDB using a SQL*Plus connection will, by default, only affect the current instance. To make changes affecting all instances that belong to the PDB, you must use the
ALTER PLUGGABLE DATABASE command with instance=all
. When using PDBs you must connect, using a dynamic database service (
net_service_name
), to an instance, as PDBs represent themselves as dynamic database services associated with one or more instances of an
Oracle RAC database.
Because, by default, the SQL*Plus prompt does not identify the current instance, you should direct your commands to the correct instance. Starting a SQL*Plus session and connecting to the database without specifying an instance directs all SQL*Plus commands to the local instance. In this case, the default instance is also the current instance.
Since the SQL*Plus prompt does not identify the current instance by default, you should direct your commands to the correct instance. Starting a SQL*Plus session and connecting to the database without specifying an instance directs all SQL*Plus commands to the local instance. In this case, the default instance is also the current instance. To connect to a different instance in SQL*Plus, issue a new
CONNECT command and specify a remote instance net service name, as shown in the following example, where
password
is the password:
Administering Database Instances and Cluster Databases 3-5
Overview of Oracle RAC Database Administration
CONNECT user_name@net_service_name
Enter password: password
Connecting as
SYSOPER
or
SYSRAC
enables you to perform privileged operations, such as instance startup and shutdown. Multiple SQL*Plus sessions can connect to the same instance at the same time. SQL*Plus automatically disconnects you from the first instance whenever you connect to another one.
Note:
Use the
SYSASM
privilege instead of the
SYSRAC
privilege to connect to and administer an Oracle ASM instance. If you use the
SYSRAC
privilege to connect to an Oracle ASM instance, then Oracle Database writes warnings to the alert log files because commands that run using the
SYSRAC
privilege on an Oracle ASM instance are deprecated.
Related Topics:
Oracle Database Administrator’s Guide
Oracle Automatic Storage Management Administrator's Guide
Oracle Database Net Services Administrator's Guide
Oracle Database Administrator’s Guide
How SQL*Plus Commands Affect Instances
Most SQL statements affect the current instance. You can use SQL*Plus to start and stop instances in the Oracle RAC database. You do not need to run SQL*Plus commands as root
on Linux and UNIX systems or as
Administrator
on Windows systems. You need only the proper database account with the privileges that you normally use for a noncluster Oracle database. Some examples of how SQL*Plus commands affect instances are:
•
ALTER SYSTEM CHECKPOINT LOCAL
affects only the instance to which you are currently connected, rather than the default instance or all instances.
•
ALTER SYSTEM CHECKPOINT
or
ALTER SYSTEM CHECKPOINT GLOBAL
affects
all
instances in the cluster database.
•
ALTER SYSTEM SWITCH LOGFILE affects only the current instance.
– To force a global log switch, use the
ALTER SYSTEM ARCHIVE LOG
CURRENT
statement.
– The
INSTANCE
option of
ALTER SYSTEM ARCHIVE LOG
enables you to archive each online redo log file for a specific instance.
describes how SQL*Plus commands affect instances.
Table 3-1 How SQL*Plus Commands Affect Instances
SQL*Plus Command Associated Instance
Always affects the current instance.
ARCHIVE LOG
3-6 Oracle Real Application Clusters Administration and Deployment Guide
Starting and Stopping Instances and Oracle RAC Databases
Table 3-1 (Cont.) How SQL*Plus Commands Affect Instances
SQL*Plus Command Associated Instance
CONNECT
Affects the default instance if no instance is specified in the
CONNECT
command.
HOST
Affects the node running the SQL*Plus session, regardless of the location of the current and default instances.
Does not affect any particular instance, but rather the database.
RECOVER
SHOW INSTANCE
Displays information about the current instance, which can be different from the default local instance if you have redirected your commands to a remote instance.
Displays parameter and SGA information from the current instance.
SHOW PARAMETER and
SHOW SGA
Always affects the current instance. These are privileged SQL*Plus commands.
STARTUP and
SHUTDOWN
Starting and Stopping Instances and Oracle RAC Databases
You can start and stop instances with Oracle Enterprise Manager, SQL*Plus, or
SRVCTL.
Both Oracle Enterprise Manager and SRVCTL provide options to start and stop all of the instances in an Oracle RAC database with a single step.
Using any tool, you can choose the startup state to which you want to start the database. The state of the database and database instance will determine what operations you can perform. You can perform certain operations only when the database is in the MOUNT (NOMOUNT) state. Performing other operations requires that the database be in the OPEN state.
Note:
Oracle does not support running more than one instance of the same database on the same node.
To start an Oracle RAC database instance on a node in the cluster, you must first start the Oracle Grid Infrastructure stack on the node. An Oracle RAC database instance will not start on a server on which the Oracle Grid Infrastructure stack is not running.
Administering Database Instances and Cluster Databases 3-7
Starting and Stopping Instances and Oracle RAC Databases
Oracle Database QoS Management Policy Workload Criticality Determines
Database Startup Order
If a user-created Oracle Database Quality of Service Management (Oracle Database
QoS Management) policy is active, then the ranked order of the performance classes determines the order in which the associated Oracle RAC databases start or request real-time LMS process slots. Using the performance class rankings ensures that mission-critical databases running in a consolidated environment have their LMS processes run in real time, thus eliminating a resource bottleneck within inter-node communication. Because the Oracle Database QoS Management policy specifies the rank of each workload, using the value of
Max(Ranks)
for each database provides a consistent expression of the expressed business criticality of each database.
The procedures in the following sections discuss starting and stopping Oracle RAC database instances:
•
Starting One or More Instances and Oracle RAC Databases Using SRVCTL
•
Stopping One or More Instances and Oracle RAC Databases Using SRVCTL
•
Stopping All Databases and Instances Using CRSCTL
•
Starting and Stopping Individual Instances Using SQL*Plus
Related Topics:
Oracle Database Concepts
Oracle Database 2 Day + Real Application Clusters Guide
Starting One or More Instances and Oracle RAC Databases Using SRVCTL
Use SRVCTL start Oracle RAC databases and instances.
Note:
This section assumes that you are using an SPFILE for your database.
Enter the following SRVCTL syntax from the command line, providing the required database name and instance name, or include multiple instance names to start multiple specific instances:
• To start or stop your entire cluster database, that is, all of the instances and its enabled services, enter the following SRVCTL commands:
$ srvctl start database -db db_unique_name [-startoption start_options]
$ srvctl stop database -db db_unique_name [-o stop_options]
The following SRVCTL command, for example, mounts all of the non-running instances of an Oracle RAC database:
$ srvctl start database -db orcl -startoption mount
• To start administrator-managed databases, enter a comma-delimited list of instance names:
$ srvctl start instance -db db_unique_name -instance instance_name_list
[-startoption start_options]
3-8 Oracle Real Application Clusters Administration and Deployment Guide
Starting and Stopping Instances and Oracle RAC Databases
In Windows you must enclose a comma-delimited list in double quotation marks
(
""
).
• To start policy-managed databases, enter a single node name:
$ srvctl start instance -db db_unique_name -node node_name
[-startoption start_options]
Note that this command also starts all enabled and non-running services that have
AUTOMATIC
management policy, and for which the database role matches one of the service's roles.
• To stop one or more instances, enter the following SRVCTL syntax from the command line:
$ srvctl stop instance -db db_unique_name [-instance "instance_name_list" |
-node node_name] [-stopoption stop_options]
You can enter either a comma-delimited list of instance names to stop several instances or you can enter a node name to stop one instance. In Windows you must enclose a comma-delimited list in double quotation marks (
""
).
This command also stops the services related to the terminated instances on the nodes where the instances were running. As an example, the following command shuts down the two instances, orcl3
and orcl4
, on the orcl
database using the immediate
stop option:
$ srvctl stop instance -db orcl -instance "orcl3,orcl4" -stopoption immediate
Related Topics:
Server Control Utility Reference
Stopping One or More Instances and Oracle RAC Databases Using SRVCTL
Use SRVCTL to stop instances and Oracle RAC databases.
The procedure for shutting down Oracle RAC instances is identical to shutting down instances in noncluster Oracle databases, with the following exceptions:
• In Oracle RAC, shutting down one instance does not interfere with the operation of other running instances.
• To shut down an Oracle RAC database completely, shut down every instance that has the database open or mounted.
• After a
NORMAL
or
IMMEDIATE
shutdown, instance recovery is not required.
Recovery is required, however, after you issue the
SHUTDOWN ABORT
command or after an instance terminates abnormally. An instance that is still running performs instance recovery for the instance that shut down. If no other instances are running, the next instance to open the database performs instance recovery for any instances needing it.
• Using the
SHUTDOWN TRANSACTIONAL
command with the
LOCAL
option is useful to shut down a particular Oracle RAC database instance. Transactions on other instances do not block this operation. If you omit the
LOCAL
option, then this operation waits until transactions on all other instances that started before you ran the
SHUTDOWN
command either commit or rollback, which is a valid approach, if you intend to shut down all instances of an Oracle RAC database.
Administering Database Instances and Cluster Databases 3-9
Starting and Stopping Instances and Oracle RAC Databases
Note:
SHUTDOWN TRANSACTIONAL
and
SHUTDOWN TRANSACTIONAL LOCAL
both perform the same action on a nonclustered database but the two commands are different on an Oracle RAC database.
Use SRVCTL to shut down an Oracle RAC database or database instance. The respective SRVCTL commands ( srvctl stop database
or srvctl stop instance
) provide shutdown options to perform an optimized transactional shutdown. Use the
TRANSACTIONAL
stop option with the srvctl stop database command and the
TRANSACTIONAL LOCAL
stop option with the srvctl stop instance
command.
Related Topics:
The srvctl stop database
command stops a database, its instances, and its services.
The srvctl stop instance
command stops instances and stops any services running on specified instances.
Oracle Database Concepts
Oracle Database Administrator’s Guide
Stopping All Databases and Instances Using CRSCTL
When you want to stop an entire node or cluster (for maintenance purposes, for example), you run either the crsctl stop crs
command on the node or the crsctl stop cluster -all
command, provided you have the required cluster privileges. These commands stop all database instances running on a server or in the cluster and ensure that their state is recovered after you restart the cluster. Using
CRSCTL also enables Oracle Clusterware to relocate services and other resources that can run elsewhere.
Using either of these CRSCTL commands to stop all database instances on a server or in the cluster can lead to the database instances being stopped similar to shutdown
abort
, which requires an instance recovery on startup. If you use SRVCTL to stop the database instances manually before stopping the cluster, then you can prevent a
shutdown abort
, but this requires that you manually restart the database instances after restarting Oracle Clusterware.
Starting and Stopping Individual Instances Using SQL*Plus
If you want to start or stop just one instance and you are connected to your local node, then you must first ensure that your current environment includes the SID for the local instance.
Note that any subsequent commands in your session, whether inside or outside a
SQL*Plus session, are associated with that same SID.
Note:
This section assumes you are using an SPFILE.
3-10 Oracle Real Application Clusters Administration and Deployment Guide
Starting and Stopping Instances and Oracle RAC Databases
To start or shutdown your local instance, initiate a SQL*Plus session and connect with the SYSRAC or SYSOPER privilege and then issue the required command. For example to start and mount an instance on your local node, run the following commands in your SQL*Plus session:
CONNECT / AS SYSRAC
STARTUP MOUNT
Note:
If you use Oracle ASM disk groups, then use the SYSASM privilege instead of the SYSRAC privilege to connect to and administer the Oracle ASM instances.
Oracle recommends that you do not use SQL*Plus to manage Oracle ASM instances in an Oracle RAC environment. Oracle Clusterware automatically manages Oracle ASM instances, as required. If manual intervention is necessary, then use respective SRVCTL commands.
You can start multiple instances from a single SQL*Plus session on one node using
Oracle Net Services. Connect to each instance in turn by using a Net Services connection string, typically an instance-specific alias from your tnsnames.ora
file.
For example, you can use a SQL*Plus session on a local node to perform a transactional shutdown for two instances on remote nodes by connecting to each in turn using the instance's individual alias name. Assume the alias name for the first instance is db1
and that the alias for the second instance is db2
. Connect to the first instance and shut it down as follows:
CONNECT /@db1 AS SYSRAC
SHUTDOWN TRANSACTIONAL
Note:
To ensure that you connect to the correct instance, you must use an alias in the connect string that is associated with just one instance. If you use a connect string that uses a TNS alias that connects to a service or an Oracle Net address that lists multiple IP addresses, then you might not be connected to the specific instance you want to shut down.
Then connect to and shutdown the second instance by entering the following from your SQL*Plus session:
CONNECT /@db2 AS SYSRAC
SHUTDOWN TRANSACTIONAL
It is not possible to start or stop multiple instances, simultaneously, with SQL*Plus, so you cannot start or stop all of the instances for a cluster database with a single
SQL*Plus command. You may want to create a script that connects to each instance in turn and start it up and shut it down. However, you must maintain this script manually if you add or drop instances.
Related Topics:
Oracle Automatic Storage Management Administrator's Guide
SQL*Plus User's Guide and Reference
Administering Database Instances and Cluster Databases 3-11
Starting and Stopping PDBs in Oracle RAC
Starting and Stopping PDBs in Oracle RAC
Administering a pluggable database (PDB) involves a small subset of the tasks required to administer a non-CDB.
Administering an Oracle RAC-based multitenant container database (
somewhat similar to administering a non-CDB. The differences are only that some administrative tasks apply to the entire CDB, some apply only to the root, and some apply to specific pluggable databases (
s). In this subset of tasks, most are the same
for a PDB and a non-CDB. There are some differences, however, such as when you modify the open mode of a PDB. Also, a PDB administrator is limited to managing a single PDB and is not affected by other PDBs in the CDB.
See Also:
Oracle Database Administrator's Guide
for more information about managing
CDBs and PDBs
You manage PDBs in an Oracle RAC-based CDB by managing services, regardless of whether the PDBs are policy managed or administrator managed. Assign one dynamic database service to each PDB to coordinate start, stop, and placement of PDBs across instances in a clustered container database.
For example, if you have a CDB called raccont
with a policy-managed PDB called spark
, which is in a server pool called prod
, then assign a service called plug
to this database using the following command: srvctl add service –db raccont –pdb spark –service plug –serverpool prod
The service plug
will be uniformly managed across all nodes in the server pool. If you want to have this service running as a singleton service in the same server pool, use the
-cardinality singleton
parameter with the preceding command.
To open the PDB spark
, you must start the respective service, plug
, as follows: srvctl start service -db raccont -service plug
To stop the service, plug
: srvctl stop service -db raccont -service plug
The PDB spark
remains open until you close the PDB using the SQL command
ALTER PLUGGABLE DATABASE PDB_NAME CLOSE IMMEDIATE;
. You can check the status of the database using the srvctl status service
command.
Because PDBs are managed using dynamic database services, typical Oracle RACbased management practices apply. So, if the service plug
is in the ONLINE state when Oracle Clusterware is shut down on a server hosting this service, then the service will be restored to its original state after the restart of Oracle Clusterware on this server. This way, starting PDBs is automated as with any other Oracle RAC database.
3-12 Oracle Real Application Clusters Administration and Deployment Guide
Verifying That Instances are Running
Note:
Unlike SQL*Plus, SRVCTL operates on a cluster database, as a whole. Starting a PDB using services therefore applies to multiple instances of the clustered
CDB at the same time, if the service is defined to run on multiple servers simultaneously, and the current status of the cluster allows for this placement.
Related Topics:
Workload Management with Dynamic Database Services
Verifying That Instances are Running
To verify that a database instance is available, use Oracle Enterprise Manager,
SRVCTL, or SQL*Plus.
•
Using SRVCTL to Verify That Instances are Running
•
Using SQL*Plus to Verify That Instances are Running
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
See Also:
Oracle Database 2 Day + Real Application Clusters Guide
for information about using Oracle Enterprise Manager to view the status of Oracle RAC database instances
Using SRVCTL to Verify That Instances are Running
You can use SRVCTL to verify that instances are running on a particular database.
The following command provides an example of using SRVCTL to check the status of the database instances for the Oracle RAC database named mail:
$ srvctl status database -db mail
This command returns output similar to the following:
Instance mail1 is running on node betal011Instance mail2 is running on node betal010
Additionally, you can check whether PDBs are running in the cluster by checking the availability of their assigned services, as follows:
$ srvctl status service -db db_unique_name -service service_name
Using SQL*Plus to Verify That Instances are Running
You can use SQL*Plus to verify that database instances are running.
1.
On any node, from a SQL*Plus prompt, connect to a database instance by using a
Net Services connection string, typically an instance-specific alias from your tnsnames.ora
file.
Administering Database Instances and Cluster Databases 3-13
Terminating Sessions On a Specific Cluster Instance
2.
CONNECT /@db1 as SYSRAC
Query the V$ACTIVE_INSTANCES view, using the following statement:
CONNECT SYS/as SYSRAC
Enter password: password
SELECT * FROM V$ACTIVE_INSTANCES;
This query returns output similar to the following:
INST_NUMBER INST_NAME
----------- -----------------
1 db1-sun:db1
2 db2-sun:db2
3 db3-sun:db3
The output columns for this example are shown in the following table.
Table 3-2 Descriptions of V$ACTIVE_INSTANCES Columns
Column
INST_NUMBER
INST_NAME
Description
Identifies the instance number.
Identifies the host name and instance name as
host_name
:
instance_name
.
Terminating Sessions On a Specific Cluster Instance
You can use the
ALTER SYSTEM KILL SESSION
statement to terminate a session on a specific instance.
When a session is terminated, any session active transactions are rolled back, and resources held by the session (such as locks and memory areas) are immediately released and available to other sessions.
Using the
ALTER SYSTEM KILL SESSION
statement enables you to maintain strict application service-level agreements in Oracle RAC environments. Often, the goal of a service-level agreement is to carry out a transaction in a specified time limit. In an
Oracle RAC environment, this may require terminating a transaction on an instance, and retrying the transaction on another instance within a specified time frame.
Note:
You can use Application Continuity to hide the cancellation of a transaction from the user, if the application initially used an Application Continuityenabled dynamic database service to connect to the database instance.
For a more granular approach to service-level management, Oracle recommends that you use Oracle Database Quality of Service Management
(Oracle Database QoS Management) for all Oracle RAC-based databases.
To terminate sessions, follow these steps:
1.
Query the value of the
INST_ID
column in the
GV$SESSION
dynamic performance view to identify which session to terminate.
3-14 Oracle Real Application Clusters Administration and Deployment Guide
Terminating Sessions On a Specific Cluster Instance
2.
Issue the
ALTER SYSTEM KILL SESSION
and specify the session index number
(SID) and serial number of a session that you identified with the
GV$SESSION dynamic performance view.
KILL SESSION 'integer1, integer2[, @integer3]'
• For
integer1
, specify the value of the SID column.
• For
integer2
, specify the value of the
SERIAL#
column.
• For the optional
integer3
, specify the ID of the instance where the session to be killed exists. You can find the instance ID by querying the
GV$
tables.
To use this statement, your instance must have the database open, and your session and the session to be terminated must be on the same instance unless you specify
integer3
.
If the session is performing some activity that must be completed, such as waiting for a reply from a remote database or rolling back a transaction, then Oracle Database waits for this activity to complete, marks the session as terminated, and then returns control to you. If the waiting lasts a minute, then Oracle Database marks the session to be terminated and returns control to you with a message that the session is marked to be terminated. The PMON background process then marks the session as terminated when the activity is complete.
Examples of Identifying and Terminating Sessions
The following examples provide three scenarios in which a user identifies and terminates a specific session. In each example, the SYSDBA first queries the
GV
$SESSION
view for the
SCOTT
user's session to identify the session to terminate, and then runs the
ALTER SYSTEM KILL SESSION
statement to terminate the session on the instance.
Example 3-1 Identify and terminate the session on an busy instance
In this example, assume that the executing session is
SYSDBA
on the instance
INST_ID=1
. The
ORA-00031
message is returned because some activity must be completed before the session can be terminated.
SQL> SELECT SID, SERIAL#, INST_ID FROM GV$SESSION WHERE USERNAME='SCOTT';
SID SERIAL# INST_ID
---------- ---------- ----------
80 4 2
SQL> ALTER SYSTEM KILL SESSION '80, 4, @2'; alter system kill session '80, 4, @2'
*
ERROR at line 1:
ORA-00031: session marked for kill
SQL>
Example 3-2 Identify and terminate the session on an idle instance
In this example, assume that the executing session is
SYSDBA
on the instance
INST_ID=1
. The session on instance
INST_ID=2
is terminated immediately when
Oracle Database executes the statement within 60 seconds.
SQL> SELECT SID, SERIAL#, INST_ID FROM GV$SESSION WHERE USERNAME='SCOTT';
SID SERIAL# INST_ID
Administering Database Instances and Cluster Databases 3-15
Overview of Initialization Parameter Files in Oracle RAC
---------- ---------- ----------
80 6 2
SQL> ALTER SYSTEM KILL SESSION '80, 6, @2';
System altered.
SQL>
Example 3-3 Using the IMMEDIATE parameter
The following example includes the optional
IMMEDIATE
clause to immediately terminate the session without waiting for outstanding activity to complete.
SQL> SELECT SID, SERIAL#, INST_ID FROM GV$SESSION WHERE USERNAME='SCOTT';
SID SERIAL# INST_ID
---------- ---------- ----------
80 8 2
SQL> ALTER SYSTEM KILL SESSION '80, 8, @2' IMMEDIATE;
System altered.
SQL>
Related Topics:
Oracle Database Administrator’s Guide
Oracle Database 2 Day + Performance Tuning Guide
Oracle Database Quality of Service Management User's Guide
Application Continuity masks many recoverable database outages
(when replay is successful) from applications and users by restoring the database session: the full session, including all states, cursors, variables, and the last transaction if there is one.
Overview of Initialization Parameter Files in Oracle RAC
When you create the database, Oracle Database creates an SPFILE in the file location
that you specify. This location can be either an Oracle ASM disk group or a
. If you manually create your database, then Oracle recommends that you create an SPFILE from an initialization parameter file (PFILE).
Note:
Oracle RAC uses a traditional PFILE only if an SPFILE does not exist or if you specify
PFILE
in your
STARTUP
command. Oracle recommends that you use an SPFILE to simplify administration, to maintain parameter setting consistency, and to guarantee parameter setting persistence across database shutdown and startup events. In addition, you can configure RMAN to back up your SPFILE.
All instances in the cluster database use the same SPFILE at startup. Because the
SPFILE is a binary file, do not directly edit the SPFILE with an editor. Instead, change
3-16 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Initialization Parameter Files in Oracle RAC
SPFILE parameter settings using Oracle Enterprise Manager or
ALTER SYSTEM
SQL statements.
When creating an SPFILE, if you include the
FROM MEMORY
clause (for example,
CREATE PFILE FROM MEMORY
or
CREATE SPFILE FROM MEMORY
), then the
CREATE
statement creates a PFILE or SPFILE using the current system-wide parameter settings. In an Oracle RAC environment, the created file contains the parameter settings from each instance. Because the
FROM MEMORY
clause requires all other instances to send their parameter settings to the instance that is trying to create the parameter file, the total execution time depends on the number of instances, the number of parameter settings on each instance, and the amount of data for these settings.
This section includes the following topics:
•
Setting SPFILE Parameter Values for Oracle RAC
•
Parameter File Search Order in Oracle RAC
•
Backing Up the Server Parameter File
Setting SPFILE Parameter Values for Oracle RAC
You can change SPFILE settings with Oracle Enterprise Manager or by using the
SET clause of the
ALTER SYSTEM
statement.
Note:
Modifying the SPFILE using tools other than Oracle Enterprise Manager or
SQL*Plus can corrupt the file and prevent database startup. To repair the file, you might be required to create a PFILE and then regenerate the SPFILE.
The examples in this section appear in ASCII text although the SPFILE is a binary file.
Assume that you start an instance with an SPFILE containing the following entries:
*.OPEN_CURSORS=500 prod1.OPEN_CURSORS=1000
The value before the period (.) in an SPFILE entry identifies the instance to which the particular parameter value belongs. When an asterisk (*) precedes the period, the value is applied to all instances that do not have a subsequent, individual value listed in the SPFILE.
For the instance with the Oracle system identifier (SID) prod1
, the
OPEN_CURSORS parameter is set to
1000
even though it has a database-wide setting of
500
. Parameter file entries that have the asterisk (*) wildcard character only affect the instances without an instance-specific entry. This gives you control over parameter settings for instance prod1
. These two types of settings can appear in any order in the parameter file.
If another DBA runs the following statement, then Oracle Database updates the setting on all instances except the instance with SID prod1
:
ALTER SYSTEM SET OPEN_CURSORS=1500 sid='*' SCOPE=SPFILE;
The SPFILE now has the following entries for
OPEN_CURSORS
:
Administering Database Instances and Cluster Databases 3-17
Overview of Initialization Parameter Files in Oracle RAC
*.OPEN_CURSORS=1500 prod1.OPEN_CURSORS=1000
Run the following statement to reset
OPEN_CURSORS
to its default value for all instances except prod1
:
ALTER SYSTEM RESET OPEN_CURSORS SCOPE=SPFILE;
The SPFILE now has just the following entry for prod1
: prod1.OPEN_CURSORS=1000
Run the following statement to reset the
OPEN_CURSORS
parameter to its default value for instance prod1
only:
ALTER SYSTEM RESET OPEN_CURSORS SCOPE=SPFILE SID='prod1';
Parameter File Search Order in Oracle RAC
Oracle Database searches for your parameter file in a particular order depending on your platform. For Oracle RAC databases, you can easily determine the location of the parameter file by using the srvctl config database
command.
On Linux and UNIX platforms, the search order is as follows:
1.
$ORACLE_HOME/dbs/spfilesid.ora
2.
$ORACLE_HOME/dbs/spfile.ora
3.
$ORACLE_HOME/dbs/initsid.ora
On Windows platforms, the search order is as follows:
1.
%ORACLE_HOME%\database\spfilesid.ora
2.
%ORACLE_HOME%\database\spfile.ora
3.
%ORACLE_HOME%\database\initsid.ora
Note:
Oracle recommends that you do not use the default SPFILE names because all instances must use the same file and they all have different SIDs. Instead, store the SPFILE on Oracle ASM. If you store the SPFILE on a cluster file system, then use the following naming convention for the SPFILE:
$ORACLE_HOME/dbs/spfiledb_unique_name.ora
. Create a PFILE named
$ORACLE_HOME/dbs/initsid.ora
that contains the name
SPFILE=ORACLE_HOME/dbs/spfiledb_unique_name.ora
.
Related Topics:
Displays the configuration for an Oracle RAC database or lists all configured databases that are registered with Oracle Clusterware.
Backing Up the Server Parameter File
Oracle recommends that you regularly back up the server parameter file for recovery purposes.
3-18 Oracle Real Application Clusters Administration and Deployment Guide
Initialization Parameter Use in Oracle RAC
Do this using Oracle Enterprise Manager (as described in the Oracle Database 2 Day +
Real Application Clusters Guide
) or use the
CREATE PFILE
statement. For example:
CREATE PFILE='/u01/oracle/dbs/test_init.ora'
FROM SPFILE='/u01/oracle/dbs/test_spfile.ora';
You can use Recovery Manager (RMAN) to create backups of the server parameter file. You can also recover an SPFILE by starting an instance using a client-side initialization parameter file. Then re-create the server parameter file using the
CREATE
SPFILE
statement. Note that if the parameter file that you use for this operation was for a single instance, then the parameter file does not contain instance-specific values, even those that must be unique in Oracle RAC instances. Therefore, ensure that your parameter file contains the appropriate settings as described earlier in this chapter.
To ensure that your SPFILE (and control files) are automatically backed up by RMAN during typical backup operations, use Oracle Enterprise Manager or the RMAN
CONTROLFILE AUTOBACKUP
statement to enable the RMAN autobackup feature
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
Oracle Database SQL Language Reference
Oracle Database Backup and Recovery Reference
Initialization Parameter Use in Oracle RAC
By default, most parameters are set to a default value and this value is the same across all instances.
However, many initialization parameters can also have different values on different
instances as described in Table 3-3
. Other parameters must either be unique or identical as described in the following sections
•
Parameters That Must Have Identical Settings on All Instances
•
Parameters That Have Unique Settings on All Instances
•
Parameters That Should Have Identical Settings on All Instances
summarizes the initialization parameters used specifically for Oracle RAC databases.
Table 3-3 Initialization Parameters Specific to Oracle RAC
Parameter
ACTIVE_INSTANCE_COUNT
ASM_PREFERRED_READ_FAI
LURE_GROUPS
CLUSTER_DATABASE
Description
This initialization parameter was deprecated in Oracle RAC 11g release 2 (11.2).
Instead, use a service with one preferred and one available instance.
Specifies a set of disks to be the preferred disks from which to read mirror data copies. The values you set for this parameter are instance specific and need not be the same on all instances.
Enables a database to be started in cluster mode. Set this parameter to
TRUE
.
Administering Database Instances and Cluster Databases 3-19
Initialization Parameter Use in Oracle RAC
Table 3-3 (Cont.) Initialization Parameters Specific to Oracle RAC
Parameter
CLUSTER_DATABASE_INSTA
NCES
CLUSTER_INTERCONNECTS
DB_NAME
DISPATCHERS
GCS_SERVER_PROCESSES
Description
Oracle RAC uses this parameter to allocate adequate memory resources. It must be set to the same value on all instances.
• For policy-managed databases, Oracle internally sets this parameter to 16
• For administrator-managed databases, Oracle internally sets it to the number of configured Oracle RAC instances
You can set this parameter to a value that is greater than the current number of instances, if you are planning to add instances. For policy-managed databases, you should set this parameter to a higher value only if you intend to run a database with more than 16 instances. In this case, set the parameter to the expected maximum number of instances on which this database will run.
Specifies an alternative cluster interconnect for the private network when there are multiple interconnects.
Notes:
• Oracle recommends that all Oracle databases and Oracle Clusterware use the same interconnect network.
• Oracle does not recommend setting the
CLUSTER_INTERCONNECTS parameter except in certain situations. See "
Administering Multiple Cluster
Interconnects on Linux and UNIX Platforms
" for more details.
• This parameter is stored in the Grid Plug and Play profile in a Grid Plug and Play environment.
If you set a value for
DB_NAME
in instance-specific parameter files, the setting must be identical for all instances.
Set the
DISPATCHERS
parameter to enable a shared server configuration, that is a server that is configured to enable many user processes to share very few server processes. With shared server configurations, many user processes connect to a dispatcher. The
DISPATCHERS
parameter may contain many attributes.
Oracle recommends that you configure at least the
PROTOCOL
and
LISTENER attributes.
PROTOCOL
specifies the network protocol for which the dispatcher process generates a listening end point.
LISTENER
specifies an alias name for the Oracle Net Services listeners. Set the alias to a name that is resolved through a naming method such as a tnsnames.ora
file. The tnsnames.ora
file contains net service names. Clients, nodes, and the Oracle Performance Manager node need this file. Oracle Enterprise Manager does not require tnsnames.ora
entries on the client for Cloud Control.
See Also:
Oracle Database Net Services Administrator's Guide for complete information about configuring the
DISPATCHERS
parameter and its attributes and for configuring the shared server
This static parameter specifies the initial number of server processes for an
Oracle RAC instance's Global Cache Service (GCS). The GCS processes manage the routing of interinstance traffic among Oracle RAC instances. The default number of GCS server processes is calculated based on system resources with a minimum setting of 2. For systems with one CPU, there is one GCS server process. For systems with two to eight CPUs, there are two GCS server processes. For systems with more than eight CPUs, the number of GCS server processes equals the number of CPUs divided by 4, dropping any fractions. For example, if you have 10 CPUs, then 10 divided by 4 means that your system has
2 GCS processes. You can set this parameter to different values on different instances.
3-20 Oracle Real Application Clusters Administration and Deployment Guide
Initialization Parameter Use in Oracle RAC
Table 3-3 (Cont.) Initialization Parameters Specific to Oracle RAC
Parameter
INSTANCE_NAME
RESULT_CACHE_MAX_SIZE
SERVICE_NAMES
SPFILE
THREAD
Description
Specifies the unique name of an instance. Clients can use this name to force their session to be connected to a specific instance in the cluster. The format of the
INSTANCE_NAME
parameter is generally
db_unique_name_instance_number
, such as orcldb_2
.
Note:
In Grid Plug and Play environments, the
INSTANCE_NAME
parameter is not required and defaults to
db_unique_name_instance_number
if not specified.
In a clustered database, you can either set
RESULT_CACHE_MAX_SIZE=0
on every instance to disable the
, or use a nonzero value on every instance to enable the result cache. To switch between enabled and disabled result cache requires that you restart every instance:
•
Enabling the result cache:
Set
RESULT_CACHE_MAX_SIZE
to a value greater than
0
, or leave the parameter unset. You can size the cache differently on individual instances.
•
Disabling the result cache:
Set
RESULT_CACHE_MAX_SIZE=0
on all instances to disable the result cache. If you set
RESULT_CACHE_MAX_SIZE=0
upon startup of any one instance, then you must set the parameter to zero on all instance startups because disabling the result cache must done clusterwide. Disabling the result cache on some instances may lead to incorrect results.
If you do not set the
RESULT_CACHE_MAX_SIZE
parameter, the parameter resolves to a default, nonzero value.
When you use services, Oracle recommends that you do not set a value for the
SERVICE_NAMES
parameter but instead you should create cluster managed services through the Cluster Managed Services page in Oracle Enterprise
Manager Cloud Control. This is because Oracle Clusterware controls the setting for this parameter for the services that you create and for the default database
service. The service features described in Workload Management with Dynamic
are not directly related to the features that Oracle provides when you set
SERVICE_NAMES
. In addition, setting a value for this parameter may override some benefits of using services.
Note:
Oracle recommends that client connections use services rather than instance names. Entries in the
SERVICE_NAMES
parameter may be used by client connections rather than the
INSTANCE_NAME
parameter value. The
SERVICE_NAMES
parameter may include one or more names and different instances may share one or more names with other instances, enabling a client to connect to either a specific instance or to any one of a set of instances, depending on the service name chosen in the connection string.
When you use an SPFILE, all Oracle RAC database instances must use the
SPFILE and the file must be on shared storage.
Specifies the number of the redo threads to be used by an instance. You can specify any available redo thread number if that thread number is enabled and is not used. If specified, this parameter must have unique values on all instances. The best practice is to use the
INSTANCE_NAME
parameter to specify redo log groups.
Related Topics:
Oracle Database Reference
Administering Database Instances and Cluster Databases 3-21
Initialization Parameter Use in Oracle RAC
Parameters That Must Have Identical Settings on All Instances
Certain initialization parameters that are critical at database creation or that affect certain database operations must have the same value for every instance in an Oracle
RAC database. Specify these parameter values in the SPFILE or in the individual
PFILEs for each instance. The following list contains the parameters that must be identical on every instance:
COMPATIBLE
CLUSTER_DATABASE
CONTROL_FILES
DB_BLOCK_SIZE
DB_DOMAIN
DB_FILES
DB_NAME
DB_RECOVERY_FILE_DEST
DB_RECOVERY_FILE_DEST_SIZE
DB_UNIQUE_NAME
INSTANCE_TYPE
(RDBMS or ASM)
PARALLEL_EXECUTION_MESSAGE_SIZE
REMOTE_LOGIN_PASSWORDFILE
UNDO_MANAGEMENT
The following parameters must be identical on every instance only if the parameter value is set to zero:
DML_LOCKS
RESULT_CACHE_MAX_SIZE
Parameters That Have Unique Settings on All Instances
When it is necessary to set parameters that have unique settings on a policy-managed database, you can ensure that instances always use the same name on particular nodes by running the srvctl modify instance -n node_name -i instance_name command for each server that can be assigned to the database's server pool. Then a unique value of the parameter can be specified for
instance_name
that is used whenever the database runs on
node_name
.
Specify the
ORACLE_SID
environment variable, which consists of the database name and the number of the
INSTANCE_NAME
assigned to the instance.
Use the
CLUSTER_INTERCONNECTS
initialization parameter to specify an alternative interconnect to the one Oracle Clusterware is using for the private network. Each instance of the Oracle RAC database gets a unique value when setting the
CLUSTER_INTERCONNECTS
initialization parameter.
Oracle Database uses the
INSTANCE_NUMBER
parameter to distinguish among instances at startup and the
INSTANCE_NAME
parameter to assign redo log groups to specific instances. The instance name can take the form
db_unique_name_instance_number
and when it has this form of name and number separated by an underscore, the number after the underscore is used as the
INSTANCE_NUMBER
. With Oracle Database 11.2 using Grid Plug and Play, you no longer have to explicitly assign instance numbers for policy-managed databases and the instance name defaults to
db_unique_name_instance_number
, where Oracle
Database assigns the instance number.
3-22 Oracle Real Application Clusters Administration and Deployment Guide
Initialization Parameter Use in Oracle RAC
When you specify
UNDO_TABLESPACE
with automatic undo management enabled, then set this parameter to a unique undo tablespace name for each instance.
If you use the
ROLLBACK_SEGMENTS
parameters, then Oracle recommends setting unique values for it by using the
SID
identifier in the SPFILE. However, you must set a unique value for
INSTANCE_NUMBER
for each instance and you cannot use a default value.
Using the
ASM_PREFERRED_READ_FAILURE_GROUPS
initialization parameter, you can specify a list of preferred read failure group names. The disks in those failure groups become the preferred read disks. Thus, every node can read from its local disks. This results in higher efficiency and performance and reduced network traffic.
The setting for this parameter is instance-specific, and the values need not be the same on all instances.
Related Topics:
Administering Multiple Cluster Interconnects on Linux and UNIX Platforms
In Oracle RAC environments that run on Linux and UNIX platforms, you can use the
CLUSTER_INTERCONNECTS
initialization parameter to specify an alternative interconnect to the one Oracle Clusterware is using for the private network.
Parameters That Should Have Identical Settings on All Instances
Oracle recommends that the parameters listed here have identical settings on all instances.
Oracle recommends that you set the values for the parameters in Table 3-4
to the same value on all instances. Although you can have different settings for these parameters on different instances, setting each parameter to the same value on all instances simplifies administration.
Table 3-4 Parameters That Should Have Identical Settings on All Instances
Parameter Description
ARCHIVE_LAG_TARGET
Different values for instances in your Oracle RAC database are likely to increase overhead because of additional automatic synchronization performed by the database processing.
When using either Oracle Streams downstream capture or Oracle
GoldenGate integrated capture mode in a downstream capture configuration with your Oracle RAC database, the value must be greater than zero.
CLUSTER_DATABASE_I
NSTANCES
LICENSE_MAX_USERS
While it is preferable for this parameter to have identical settings across all Oracle RAC database instances, it is not required.
Because this parameter determines a database-wide limit on the number of users defined in the database, it is useful to have the same value on all instances of your database so you can see the current value no matter which instance you are using. Setting different values may cause Oracle Database to generate additional warning messages during instance startup, or cause commands related to database user management to fail on some instances.
Administering Database Instances and Cluster Databases 3-23
Converting an Administrator-Managed Database to a Policy-Managed Database
Table 3-4 (Cont.) Parameters That Should Have Identical Settings on All Instances
Parameter Description
LOG_ARCHIVE_FORMAT
If you do not use the same value for all your instances, then you unnecessarily complicate media recovery. The recovering instance expects the required archive log file names to have the format defined by its own value of
LOG_ARCHIVE_FORMAT
, regardless of which instance created the archive log files.
Databases that support Oracle Data Guard, either to send or receive archived redo log files, must use the same value of
LOG_ARCHIVE_FORMAT
for all instances.
SPFILE
If this parameter does not identify the same file to all instances, then each instance may behave differently and unpredictably in fail over, load-balancing, and during normal operations.
Additionally, a change you make to the SPFILE with an
ALTER
SYSTEM SET
or
ALTER SYSTEM RESET
command is saved only in the SPFILE used by the instance where you run the command.
Your change is not reflected in instances using different SPFILEs.
If the SPFILE values are different in instances for which the values were set by the server, then you should restart the instances that are not using the default SPFILE.
TRACE_ENABLED
UNDO_RETENTION
If you want diagnostic trace information to be always available for your Oracle RAC database, you must set
TRACE_ENABLED
to
TRUE
on all of your database instances. If you trace on only some of your instances, then diagnostic information might not be available when required should the only accessible instances be those with
TRACE_ENABLED
set to
FALSE
.
By setting different values for
UNDO_RETENTION
in each instance, you are likely to reduce scalability and encounter unpredictable behavior following a failover. Therefore, you should carefully consider whether there are any benefits before you assign different values for this parameter to the instances in your Oracle
RAC database.
Related Topics:
Oracle Streams Replication Administrator's Guide
Converting an Administrator-Managed Database to a Policy-Managed
Database
You can convert an administrator-managed database to a policy-managed database.
Note:
If the administrator-managed database is configured for a low-privileged user and you attempt to convert the database to a policy-managed database, then you must manually add a wallet (if one does not already exist) for this low privileged user, so that a Windows service for Oracle Database can be created.
To convert an administrator-managed database:
3-24 Oracle Real Application Clusters Administration and Deployment Guide
Converting an Administrator-Managed Database to a Policy-Managed Database
1.
2.
Check the current configuration of all services and the database (if you make a mistake and need to recover, then you can know what the configuration looked like when you began), as follows: srvctl config database -db db_unique_name srvctl config service -db db_unique_name
Create a server pool for the policy-managed database (you must be a cluster administrator to do this), as follows: srvctl add srvpool -serverpool server_pool -min 0 -max n
In the preceding command, 0 is the minimum number of servers you want in the server pool and
n
is the maximum.
Note:
This step does not necessarily place servers in the newly-created server pool.
If there are no servers in the Free pool from which the new server pool can allocate servers, for example, then you may have to use the srvctl relocate server
command to relocate a server from another server pool once the conversion is complete.
3.
4.
Stop the database using Oracle Enterprise Manager or SRVCTL, as follows: srvctl stop database -db db_unique_name
Modify the database to be in the new server pool, as follows: srvctl modify database -db db_unique_name -serverpool server_pool
5.
Add a service user to the wallet, as follows: crsctl add wallet -type OSUSER -user user_name -passwd
6.
Check the status of the database to confirm that it is now policy managed by
repeating the commands in step 1 .
Configure Oracle Enterprise Manager to recognize the change you made in the previous procedure, as follows:
1.
In order for Oracle Enterprise Manager Cloud Control to recognize the new database instances, you must change the instance name from
db_unique_name#
to
db_unique_name_#
(notice the additional underscore (_) before the number sign (#) character).
2.
Rename the orapwd
file in the dbs/database
directory (or create a new orapwd file by running the orapwd
command).
By default, there is an orapwd
file with the instance name appended to it, such as orapwdORCL1
. You must change the name of the file to correspond to the instance name you changed in the previous step. For example, you must change orapwdORCL1
to orapwdORCL_1
or create a new orapwd
file.
You cannot directly convert a policy-managed database to an administrator-managed database. Instead, you can remove the policy-managed configuration using the srvctl remove database
and srvctl remove service
commands, and then register the same database as an administrator-managed database using the srvctl add database
and srvctl add instance
commands. Once you register the
Administering Database Instances and Cluster Databases 3-25
Managing Memory Pressure for Database Servers database and instance, you must use the srvctl add service
command to add back the services as you removed them.
Services for administrator-managed databases continue to be defined by the
PREFERRED
and
AVAILABLE
definitions. For policy-managed databases, a service is defined to a database server pool and can either be uniform (running on all instances in the server pool) or singleton (running on only one instance in the server pool). If you change the management policy of the database, then you must recreate the database services to be either uniform/singleton or
PREFERRED
/
AVAILABLE
, depending upon which database management policy you choose.
Related Topics:
Server Control Utility Reference
Managing Memory Pressure for Database Servers
Enterprise database servers can use all available memory due to too many open sessions or runaway workloads. Running out of memory can result in failed transactions or, in extreme cases, a restart of the server and the loss of a valuable resource for your applications. Memory Guard detects
on a server in real time and redirects new sessions to other servers to prevent using all available memory on the stressed server.
When Oracle Database QoS Management is enabled and managing an Oracle
Clusterware server pool, Cluster Health Monitor sends a metrics stream that provides real-time information about memory resources for the cluster servers to Memory
Guard. This information includes the following:
• Amount of available memory
• Amount of memory currently in use
If Memory Guard determines that a node is experiencing memory pressure, then the database services managed by Oracle Clusterware are stopped on that node, preventing new connections from being created. After the memory stress is relieved, the services on that node are restarted automatically, and the listener starts sending new connections to that server. The memory pressure can be relieved in several ways
(for example, by closing existing sessions or by user intervention).
Rerouting new sessions to different servers protects the existing workloads on the memory-stressed server and enables the server to remain available. Memory Guard is a feature of Oracle RAC that manages the memory pressure for servers, adding a new resource protection capability in managing service levels for applications hosted on
Oracle RAC databases.
Quiescing Oracle RAC Databases
The procedure for quiescing Oracle RAC databases is identical to quiescing a noncluster database.
You use the
ALTER SYSTEM QUIESCE RESTRICTED
statement from one instance.
You cannot open the database from any instance while the database is in the process of being quiesced. When all non-DBA sessions become inactive, the
ALTER SYSTEM
QUIESCE RESTRICTED
statement finishes, and the database is considered as in a quiesced state. In an Oracle RAC environment, this statement affects all instances, not just the one from which the statement is issued.
3-26 Oracle Real Application Clusters Administration and Deployment Guide
Administering Multiple Cluster Interconnects on Linux and UNIX Platforms
To successfully issue the
ALTER SYSTEM QUIESCE RESTRICTED
statement in an
Oracle RAC environment, you must have the Database Resource Manager feature activated, and it must have been activated since instance startup for all instances in the cluster database. It is through the facilities of the Database Resource Manager that non-DBA sessions are prevented from becoming active. Also, while this statement is in effect, any attempt to change the current resource plan is queued until after the system is unquiesced.
These conditions apply to Oracle RAC:
• If you issued the
ALTER SYSTEM QUIESCE RESTRICTED
statement but Oracle
Database has not finished processing it, you cannot open the database.
• You cannot open the database if it is in a quiesced state.
• The
ALTER SYSTEM QUIESCE RESTRICTED
and
ALTER SYSTEM UNQUIESCE statements affect all instances in an Oracle RAC environment, not just the instance that issues the command.
Note:
You cannot use the quiesced state to take a cold backup. This is because Oracle
Database background processes may still perform updates for Oracle
Database internal purposes even while the database is in quiesced state. In addition, the file headers of online data files continue to look like they are being accessed. They do not look the same as if a clean shutdown were done.
You can still take online backups while the database is in a quiesced state.
Related Topics:
Oracle Database Administrator’s Guide
Oracle Database SQL Language Reference
Administering Multiple Cluster Interconnects on Linux and UNIX
Platforms
In Oracle RAC environments that run on Linux and UNIX platforms, you can use the
CLUSTER_INTERCONNECTS
initialization parameter to specify an alternative interconnect to the one Oracle Clusterware is using for the private network.
Note:
The
CLUSTER_INTERCONNECTS
initialization parameter should not be set to highly available IP (HAIP) addresses provided by Redundant Interconnect
Usage. HAIP addresses are recognized automatically.
If you set multiple values for
CLUSTER_INTERCONNECTS
, then Oracle Database uses all of the network interfaces that you specify for the interconnect, providing load balancing if all of the listed interconnects remain operational. You must use identical values, including the order in which the interconnects are listed, on all instances of your database when defining multiple interconnects with this parameter.
Administering Database Instances and Cluster Databases 3-27
Administering Multiple Cluster Interconnects on Linux and UNIX Platforms
Note:
Oracle does not recommend setting the
CLUSTER_INTERCONNECTS initialization parameter, which overrides the default interconnect settings at the operating system level.
Instead, the best practice is to use Redundant Interconnect Usage, available with
Oracle Grid Infrastructure 11g release 2 (11.2) for Oracle RAC and Oracle Real
Application Clusters One Node 11g release 2 (11.2) databases, and later. For databases that precede Oracle Database 11g release 2 (11.2), use operating system-based network bonding technologies to enable high availability (and load balancing) for network interface cards meant to be used as the cluster interconnect. If you want to use multiple database versions in one cluster, you can combine both techniques.
Redundant Interconnect Usage will use the interfaces as presented on the operating system level, regardless of bonding. For more information regarding bonding technologies contact your operating system vendor.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Use Cases for Setting the CLUSTER_INTERCONNECTS Parameter
The
CLUSTER_INTERCONNECTS
initialization parameter requires an IP address. It enables you to specify multiple IP addresses, separated by colons. Oracle RAC network traffic is distributed between the specified IP addresses.
Note:
• Oracle does not recommend setting the
CLUSTER_INTERCONNECTS parameter when using a policy-managed database.
• Oracle recommends that all databases and Oracle Clusterware use the same interconnect network.
Typically, you set the
CLUSTER_INTERCONNECTS
parameter only in the following situations:
• The cluster is running multiple databases and you need the interconnect traffic to be separated and you do not use Redundant Interconnect Usage.
• You have a single IP address that is made highly available by the operating system, and it does not have a stable interface name (for example, the name can change when you restart).
Do not set the
CLUSTER_INTERCONNECTS
parameter for the following common configurations:
• If you want to use Redundant Interconnect Usage.
• If you have only one cluster interconnect.
• If the default cluster interconnect meets the bandwidth requirements of your
Oracle RAC database, which is typically the case.
3-28 Oracle Real Application Clusters Administration and Deployment Guide
Customizing How Oracle Clusterware Manages Oracle RAC Databases
Consider the following important points when specifying the
CLUSTER_INTERCONNECTS
initialization parameter:
• The
CLUSTER_INTERCONNECTS
initialization parameter is useful only in Linux and UNIX environments where UDP IPC is enabled.
• Specify a different value for each instance of the Oracle RAC database when setting the
CLUSTER_INTERCONNECTS
initialization parameter in the parameter file.
• The IP addresses you specify for the different instances of the same database on different nodes must belong to network adapters that connect to the same interconnect network.
• If you specify multiple IP addresses for this parameter, then list them in the same order for all instances of the same database. For example, if the parameter for the first instance on node1
lists the IP addresses of the alt0:
, fta0:
, and ics0: devices in that order, then the parameter for the second instance on node2
must list the IP addresses of the equivalent network adapters in the same order.
• If an operating system error occurs while Oracle Database is writing to the interconnect that you specify with the
CLUSTER_INTERCONNECTS
parameter, then Oracle Database returns an error even if some other interfaces are available.
This is because the communication protocols between Oracle Database and the interconnect can vary greatly depending on your platform. See your Oracle
Database platform-specific documentation for more information.
Example
Consider setting
CLUSTER_INTERCONNECTS
when a single cluster interconnect cannot meet your bandwidth requirements. You may need to set this parameter in data warehouse environments with high interconnect bandwidth demands from one or more databases that cannot use Redundant Interconnect Usage.
For example, if you have two databases with high interconnect bandwidth requirements, then you can override the default interconnect provided by your operating system and nominate a different interconnect for each database using the following syntax in each server parameter file where ipn
is an IP address in standard dot-decimal format, for example:
144.25.16.214
:
Database One: crm1.CLUSTER_INTERCONNECTS = ip1
Database Two: ext1.CLUSTER_INTERCONNECTS = ip2
If you have one database with high bandwidth demands, then you can nominate multiple interconnects using the following syntax:
CLUSTER_INTERCONNECTS = ip1:ip2:...:ipn
Related Topics:
Oracle Database Reference
Customizing How Oracle Clusterware Manages Oracle RAC Databases
Use these examples to minimize Oracle Clusterware control over Oracle RAC databases, which you may need to do during upgrades.
By default, Oracle Clusterware controls database restarts in Oracle RAC environments. In some cases, you may need to minimize the level of control that
Administering Database Instances and Cluster Databases 3-29
Customizing How Oracle Clusterware Manages Oracle RAC Databases
Oracle Clusterware has over your Oracle RAC database, for example, during database upgrades.
Note:
When using third-party clusterware, Oracle recommends that you use Oracle
Clusterware to manage the Oracle RAC instances. If you set the instance to manual and start it with third-party clusterware, then do not use the thirdparty clusterware to monitor and restart database instances because Oracle
Clusterware must do that.
To prevent Oracle Clusterware from restarting your Oracle RAC database when you restart your system, or to avoid restarting failed instances more than once, configure a management policy to define the degree of control. There are two management policies: AUTOMATIC, which is the default, and MANUAL. If the management policy is set to AUTOMATIC, the database is automatically restored to its previous running condition (started or stopped) upon restart of the database host computer. If
MANUAL, the database is never automatically restarted upon restart of the database host computer. A MANUAL setting does not prevent Oracle Restart from monitoring the database while it is running and restarting it if a failure occurs.
Use SRVCTL commands to display and change the Oracle Clusterware management policies, as shown in the following examples:
Example 1: Display the Current Management Policy
Use the following command syntax to display the current management policy where
db_unique_name
is the name of the database for which you want to change management policies: srvctl config database -db db_unique_name -all
Example 2: Change the Current Management Policy to Another Management
Policy
Use the following SRVCTL command syntax to change the current management policy to either AUTOMATIC, MANUAL, or NORESTART: srvctl modify database -db db_unique_name -policy [AUTOMATIC | MANUAL | NORESTART]
This command syntax sets the resource attribute of the database resource.
Example 3: Specify a Management Policy for a New Database
When you add a new database using the srvctl add database
command, you can use the
-policy
parameter to specify the management policy as either
AUTOMATIC
,
MANUAL
, or
NORESTART
, as shown in the following example where
db_unique_name
is the name of the database: srvctl add database -db db_unique_name -policy [AUTOMATIC | MANUAL | NORESTART]
-oraclehome $ORACLE_HOME -dbname DATA
This command syntax places the new database under the control of Oracle
Clusterware. If you do not provide a management policy option, then Oracle Database uses the default value of automatic
. After you change the management policy, the
Oracle Clusterware resource records the new value for the affected database.
3-30 Oracle Real Application Clusters Administration and Deployment Guide
Advanced Oracle Enterprise Manager Administration
Related Topics:
Displays the configuration for an Oracle RAC database or lists all configured databases that are registered with Oracle Clusterware.
Modifies the configuration for a database.
Adds a database configuration to Oracle Clusterware.
Advanced Oracle Enterprise Manager Administration
You can install, configure, and monitor an Oracle RAC database from a single location using Oracle Enterprise Manager Cloud Control.
This section provides advanced administration tasks that are not covered inOracle
Database 2 Day + Real Application Clusters Guide
or in "Overview of Monitoring and
Tuning Oracle RAC Databases".
This section includes the following topics:
•
Using Oracle Enterprise Manager Cloud Control to Discover Nodes and Instances
•
Other Oracle Enterprise Manager Capabilities
•
Administering Jobs and Alerts in Oracle RAC
Using Oracle Enterprise Manager Cloud Control to Discover Nodes and Instances
Discovering Oracle RAC database and instance targets in Oracle Enterprise Manager enables monitoring and administration.
Oracle Enterprise Manager Cloud Control
enables you to use the Oracle Enterprise
Manager console interface to discover Oracle RAC database and instance targets.
If the Oracle Enterprise Manager Cloud Control agents are installed on a cluster that has an Oracle RAC database, then Oracle RAC database targets are discovered at install time. You can use the console interface to discover targets if a database is created after agents are installed or if a database is not automatically discovered at agent install time.
To discover nodes and instances, use Oracle Enterprise Manager Cloud Control as follows:
1.
2.
3.
4.
5.
Log in to Oracle Enterprise Manager and click the Targets tab.
Click the Database tab to view all of the available targets. The column labeled
Types
shows the Oracle RAC databases using the entry Cluster Database.
Add the database target by selecting the target name, then clicking Add. The Add
Database Target: Specify Host page appears, which enables you to add databases, listeners, and Oracle ASM as monitored targets.
Click the flashlight icon to display the available host names, select a host, then click Continue. The Add Database: Specify Source page appears.
Either request Oracle Enterprise Manager to discover only noncluster databases and listeners, or to discover all cluster databases, noncluster databases, and listeners on the cluster, then click Continue.
Administering Database Instances and Cluster Databases 3-31
Advanced Oracle Enterprise Manager Administration
6.
If this procedure did not discover your reconfigured cluster database and all of its instances, you can use the Targets Discovered on Cluster page to manually configure your cluster database and noncluster databases.
Other Oracle Enterprise Manager Capabilities
This section lists Oracle Enterprise Manager capabilities available with Oracle
Enterprise Manager 12c.
• The Oracle Grid Infrastructure/Oracle RAC Provisioning deployment procedure provisions Oracle RAC 12c and Oracle Grid Infrastructure. This procedure also has a feature called Profiles, which enables you to record the inputs and subsequently use them for repeated deployments.
• Dynamic prerequisites for the new procedures enable Oracle Enterprise Manager, when connected to My Oracle Support (formerly OracleMetaLink), to download the latest prerequisites and tools for Oracle RAC provisioning.
• The existing One-Click Extend Cluster Database capability now supports Oracle
RAC 12c stack.
• The existing Delete/Scale down Oracle Real Application Clusters capability is certified with Oracle RAC 12c clusters.
• The existing Oracle Database Provisioning procedure now supports provisioning of single instances of Oracle Database 12c.
• A new deployment procedure—Oracle Grid Infrastructure Provisioning for
Standalone Servers—has been introduced to provision Oracle Grid Infrastructure
12c for noncluster databases.
Administering Jobs and Alerts in Oracle RAC
The Cluster Database Home page shows all of the instances in the Oracle RAC database and provides an aggregate collection of several Oracle RAC-specific statistics
Automatic Workload Repository (AWR)
for server manageability.
You do not need to navigate to an instance-specific page to see these details. However, on the Cluster Database Home page, if an instance is down that should be operating, or if an instance has a high number of alerts, then you can drill down to the instancespecific page for each alert.
To perform specific administrative tasks as described in the remainder of this section, log in to the target Oracle RAC database, navigate to the Cluster Database Home page, and click the Administration tab.
This section includes the following topics:
•
Administering Jobs in Oracle RAC
•
Administering Alerts in Oracle RAC with Oracle Enterprise Manager
•
Using Defined Blackouts in Oracle Enterprise Manager
Administering Jobs in Oracle RAC
You can administer Oracle Enterprise Manager jobs at both the database and instance levels. For example, you can create a job at the cluster database level to run on any
3-32 Oracle Real Application Clusters Administration and Deployment Guide
Advanced Oracle Enterprise Manager Administration active instance of the target Oracle RAC database. Or you can create a job at the instance level to run on the specific instance for which you created it. If there is a failure, then recurring jobs can run on a surviving instance.
Because you can create jobs at the instance level, cluster level, or cluster database level, jobs can run on any available host in the cluster database. This applies to scheduled jobs as well. Oracle Enterprise Manager also displays job activity in several categories, including,
Active
,
History
, and
Library
.
Use the Jobs tab to submit operating system scripts and SQL scripts and to examine scheduled jobs. For example, to create a backup job for a specific Oracle RAC database:
1.
2.
Click Targets and click the database for which you want to create the job.
Log in to the target database.
3.
4.
When Oracle Enterprise Manager displays the Database Home page, click
Maintenance
.
Complete the Enterprise Manage Job Wizard pages to create the job.
Administering Alerts in Oracle RAC with Oracle Enterprise Manager
You can use Oracle Enterprise Manager to configure Oracle RAC environment alerts.
You can also configure special Oracle RAC database tests, such as global cache converts, consistent read requests, and so on.
Oracle Enterprise Manager distinguishes between database- and instance-level alerts in Oracle RAC environments. Alert thresholds for instance-level alerts, such as archive log alerts, can be set at the instance target level. This function enables you to receive alerts for the specific instance if performance exceeds your threshold. You can also configure alerts at the database level, such as setting alerts for tablespaces, to avoid receiving duplicate alerts at each instance.
Related Topics:
Oracle Database PL/SQL Packages and Types Reference
See Also:
Oracle Technology Network for an example of configuring alerts in Oracle
RAC, and Oracle Database PL/SQL Packages and Types Reference for information about using packages to configure thresholds
Using Defined Blackouts in Oracle Enterprise Manager
You can define blackouts (which are time periods in which database monitoring is suspended so that maintenance operations do not skew monitoring data or generate needless alerts) for all managed targets of an Oracle RAC database to prevent alerts from occurring while performing maintenance. You can define blackouts for an entire cluster database or for specific cluster database instances.
Administering Database Instances and Cluster Databases 3-33
Advanced Oracle Enterprise Manager Administration
3-34 Administration and Deployment Guide
4
Administering Oracle RAC One Node
Oracle Real Application Clusters One Node (Oracle RAC One Node) is a single instance of an Oracle Real Application Clusters (Oracle RAC) database that runs on one node in a cluster. This option adds to the flexibility that Oracle offers for database consolidation. You can consolidate many databases into one cluster with minimal overhead while also providing the high availability benefits of failover protection, online rolling patch application, and rolling upgrades for the operating system and
Oracle Clusterware.
This chapter includes the following topics:
•
Creating an Oracle RAC One Node Database
•
•
Creating an Oracle RAC One Node Database
You can create Oracle RAC One Node databases by using Rapid Home Provisioning or the Database Configuration Assistant (DBCA), as with any other Oracle database
(manually created scripts are also a valid alternative).
You can create an Oracle RAC One Node database using Rapid Home Provisioning and the rhpctl add database
command with the
-dbtype RACONENODE paramater. You can also include an Oracle RAC One Node database using the rhpctl add workingcopy
command.
Oracle RAC One Node databases may also be the result of a conversion from either a single-instance Oracle database (using rconfig
, for example) or an Oracle RAC database. Typically, Oracle-provided tools register the Oracle RAC One Node database with Oracle Clusterware. Depending on your configuration, automatic registration of an Oracle RAC One Node database with Oracle Clusterware may not have happened. If this is the case, then follow the steps in this section to register the
Oracle RAC One Node database with Oracle Clusterware.
Note:
Oracle recommends that you manage Oracle RAC One Node databases with
Server Control Utility (SRVCTL). You can only perform certain operations
(such as Online Database Relocation) using SRVCTL.
If your Oracle RAC One Node database did not register automatically with Oracle
Clusterware, then use the srvctl add database
command to add an Oracle RAC
One Node database to your cluster. For example:
Administering Oracle RAC One Node 4-1
Converting Databases
$ srvctl add database -dbtype RACONENODE [-server server_list]
[-instance instance_name] [-timeout timeout]
Use the
-server
option and the
-instance
option when adding an administratormanaged Oracle RAC One Node database.
For Oracle RAC One Node databases, you must configure at least one dynamic database service (in addition to and opposed to the default database service). When using an administrator-managed Oracle RAC One Node database, service registration is performed as with any other Oracle RAC database. When you add services to a policy-managed Oracle RAC One Node database, SRVCTL does not accept any placement information, but instead configures those services using the value of the
SERVER_POOLS
attribute.
Note:
When adding an administrator-managed Oracle RAC One Node database, you can optionally supply an instance prefix with the
-instance
instance_name
option of the srvctl add database
command. The name of the instance will then be
prefix_1
. If you do not specify an instance prefix, then the first 12 characters of the unique name of the database becomes the prefix. The instance name changes to
prefix_2
during an online database relocation and reverts back to
prefix_1
during a subsequent online database relocation. The same instance name is used on failover.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Adds a database configuration to Oracle Clusterware.
Using DBCA in Interactive Mode to Add Database Instances to Target Nodes
Converting Databases
Using SRVCTL, you can convert an Oracle RAC database with one instance to an
Oracle RAC One Node database and vice versa.
This section includes the following topics:
•
Converting a Database from Oracle RAC to Oracle RAC One Node
•
Converting a Database from Oracle RAC One Node to Oracle RAC
Converting a Database from Oracle RAC to Oracle RAC One Node
Use SRVCTL to convert an Oracle RAC database to an Oracle RAC One Node database.
Before converting an Oracle RAC database to an Oracle RAC One Node database, you must first ensure that the Oracle RAC database has only one instance. If your Oracle
RAC database is administrator managed and has more than one instance, then you must remove all instances except one using the srvctl remove instance command. If your Oracle RAC database is policy managed and has more than one instance, then you must stop all instances except one using the srvctl stop instance
command.
4-2 Oracle Real Application Clusters Administration and Deployment Guide
Converting Databases
If the Oracle RAC database is administrator managed, then you must change the configuration of all services to set the preferred instance to the instance that you want to keep as an Oracle RAC One Node database after conversion. If any service had a
PRECONNECT TAF
policy, then its TAF policy must be updated to
BASIC
or
NONE before starting the conversion process. These services must no longer have any available instance.
If the Oracle RAC database is policy managed, then you must change the configuration of all services so that they all use the same server pool before you convert the Oracle RAC database to an Oracle RAC One Node database.
You can convert an Oracle RAC database with one instance to an Oracle RAC One
Node database using the srvctl convert database
command, as follows:
$ srvctl convert database -db db_unique_name -dbtype RACONENODE
[-instance instance_name -timeout timeout]
-w timeout]
Note:
An Oracle RAC database that you want to convert to Oracle RAC One Node must either use Oracle Managed Files (to enable automatic thread allocation) or have at least two redo threads.
Related Topics:
Converting a Database from Oracle RAC One Node to Oracle RAC
You can convert an Oracle RAC One Node database to an Oracle RAC database by logging in as the Oracle RAC One Node database owner and entering the following
SRVCTL command: srvctl convert database -db db_unique_name -dbtype RAC
If you are relocating the database you want to convert to Oracle RAC using online database relocation, or an online database relocation has failed, then you must either quit or complete the relocation before you run the srvctl convert database command.
After you run this command, you must create server pools for each database service, in addition to the database server pool. The values for
SERVER_NAMES
for the server pools used by the database services must be set to the node that you converted from an Oracle RAC One Node to an Oracle RAC node. You can use the CRSCTL utility or
Oracle Enterprise Manager to create and configure the server pools.
Converting an administrator-managed Oracle RAC One Node database to an Oracle
RAC database configures all database services so that the single-instance database is the preferred instance for that service. After you convert the database, you can add instances to your database by using the srvctl add instance
command.
Converting a policy-managed Oracle RAC One Node database to an Oracle RAC database sets all database services to UNIFORM cardinality. It also results in reusing the server pool in which the database currently runs. The conversion reconfigures the
Administering Oracle RAC One Node 4-3
Online Database Relocation database to run on all nodes in the server pool. The command does not start any additional instances but running the srvctl start database
command starts the database on all nodes in the server pool.
Related Topics:
Online Database Relocation
You can relocate an Oracle RAC One Node database to another node while still maintaining service availability using the online database relocation feature.
Only during a planned online database relocation is a second instance of an Oracle
RAC One Node database created, so that any database sessions can continue while the database is relocated to a new node. You can only use online database relocation with
Oracle RAC One Node databases but you cannot use online database relocation with
Oracle RAC databases regardless of their management style (either administrator or policy managed).
You can use the srvctl relocate database
command configure the amount of time after the relocated database starts and services are migrated, before the former instance of the database stops. This configured amount of time is not an upper bound on the amount of time taken by the entire operation, but only controls how long the relocated database waits for connections to migrate from the former instance to the new instance, before stopping the former instance.
Online database relocation occurs, as follows:
1.
2.
Start a new database instance in a different location.
Move all the services to the relocated instance.
3.
Wait for all the connections to migrate to the relocated instance.
4.
Shut down the former database instance, forcing any remaining connections to move to the relocated instance.
The online relocation timeout is the amount of time you configure to complete step 3.
If your Oracle RAC One Node database is administrator managed, then the target node to which you want to relocate the database instance must be part of the Free server pool at the moment you initiate the relocation. If you have a spare target node in the Free server pool, then this node is added to the candidate list for the Oracle RAC
One Node database.
4-4 Oracle Real Application Clusters Administration and Deployment Guide
Online Database Relocation
Note:
• When you relocate a database instance to a target node that is not currently in the candidate server list for the database, you must copy the password file, if configured, to the target node, unless you use shared password files stored in Oracle ASM.
When you use password file-based authentication for remote management of Oracle RAC One Node databases without any shared password file, you must have two password files on each node where the database can run: one named
SID_prefix_1
and the other named
SID_prefix_2
. You must recopy both of these files to all candidate nodes every time you update the password file. This is true for both policy-managed and administrator-managed databases.
Oracle recommends using Oracle Clusterware to start and stop the database, and defining users in the data dictionary for other management.
• Before you relocate a database instance, you must ensure that the database service user is added to the wallet. Run crsctl query wallet -type OSUSER -all
to check whether the database service user is in the wallet. If not, then run crsctl add wallet -type
OSUSER -user user_name -passwd
to add the database service user to the wallet.
Use the srvctl relocate database
command to initiate relocation of an Oracle
RAC One Node database. For example:
$ srvctl relocate database -d rac1 -n node7
Related Topics:
Oracle Database Administrator’s Guide
Administering Oracle RAC One Node 4-5
Online Database Relocation
4-6 Administration and Deployment Guide
5
Workload Management with Dynamic
Database Services
Workload management includes load balancing, enabling clients for Oracle Real
Application Clusters (Oracle RAC), distributed transaction processing, and services.
This chapter includes the following topics:
•
•
•
Enabling Clients for Oracle RAC
•
Distributed Transaction Processing in Oracle RAC
•
•
Measuring Performance by Service Using the Automatic Workload Repository
•
Automatic Workload Repository Service Thresholds and Alerts
•
•
•
•
•
Connecting to a Service: An Example
Connection Load Balancing
Oracle Net Services provides the ability to distribute client connections across the instances in an Oracle RAC configuration.
There are two types of load balancing that you can implement: client-side and serverside load balancing. Client-side load balancing distributes the connection requests across the listeners, independently at each client. With server-side load balancing, the
SCAN listener directs a connection request to the best instance currently providing the service, based on the
-clbgoal
and
-rlbgoal
settings for the service.
The SCAN listener is aware of the HTTP protocol so that it can redirect HTTP clients to the appropriate handler, which can reside on different nodes in the cluster than the node on which the SCAN listener resides.
In an Oracle RAC database, client connections should use both types of connection load balancing.
•
Workload Management with Dynamic Database Services 5-1
Connection Load Balancing
•
•
•
Client-Side Connection Configuration for Older Clients
Related Topics:
Oracle Database Net Services Administrator's Guide
Server-Side Load Balancing
When you create an Oracle RAC database with DBCA, it automatically:
• Configures and enables server-side load balancing
• Creates a sample client-side load balancing connection definition in the tnsnames.ora
file on the server
The Oracle Clusterware Database Agent is responsible for managing the
LISTENER_NETWORKS
parameter.
Note:
Note: If you set the
REMOTE_LISTENER
parameter manually, then set this parameter to
scan_name:scan_port
.
FAN, Fast Connection Failover, and the load balancing advisory depend on an accurate connection load balancing configuration that includes setting the connection load balancing goal for the service. You can use a goal of either
LONG
or
SHORT
for connection load balancing. These goals have the following characteristics:
•
SHORT
: Use the
SHORT
connection load balancing method for applications that use run-time load balancing. When using connection pools that are integrated with Load Balancing Advisory, set the
CLB_GOAL
to
SHORT
. The following example modifies the service known as oltpapp
, using SRVCTL to set the connection load balancing goal to
SHORT
:
$ srvctl modify service -db db_unique_name -service oltpapp -clbgoal SHORT
•
LONG
: Use the
LONG
connection load balancing method if run-time load balancing is not required. This is typical for batch operations.
LONG
is the default connection load balancing goal. The following is an example of modifying a service, batchconn
, using SRVCTL to define the connection load balancing goal for long-lived sessions:
$ srvctl modify service -db db_unique_name -service batchconn -clbgoal LONG
Generic Database Clients
Oracle Net Services enables you to add the
CONNECT_TIMEOUT
,
RETRY_COUNT
, and
TRANSPORT_CONNECT_TIMEOUT
parameters to the tnsnames.ora
connection string.
For example, when using SCAN addresses for the remote listeners at the database: jdbc:oracle:thin:@(DESCRIPTION =
(TRANSPORT_CONNECT_TIMEOUT=3)(CONNECT_TIMEOUT=60)
5-2 Oracle Real Application Clusters Administration and Deployment Guide
Connection Load Balancing
(RETRY_COUNT=3)(FAILOVER=ON)
(ADDRESS_LIST =(ADDRESS=(PROTOCOL=tcp)
(HOST=CLOUD-SCANVIP.example.com)(PORT=5221))
(CONNECT_DATA=(SERVICE_NAME=orcl)))
Remote_listeners=CLOUD-SCANVIP.example.com:5221
For example, when using remote listeners pointing to VIPs at the database: jdbc:oracle:thin:@(DESCRIPTION =
(TRANSPORT_CONNECT_TIMEOUT=3)
(CONNECT_TIMEOUT=60)(RETRY_COUNT=20)
(RETRY_DELAY=3)(FAILOVER=ON)
(ADDRESS_LIST=
(ADDRESS=(PROTOCOL=tcp)(HOST=CLOUD-VIP1)(PORT=1521) )
(ADDRESS=(PROTOCOL=tcp)(HOST=CLOUD-VIP2)(PORT=1521) )
(ADDRESS=(PROTOCOL=tcp)(HOST=CLOUD-VIP3)(PORT=1521) ))
(CONNECT_DATA=(SERVICE_NAME=GOLD)))
The value of these parameters is expressed in seconds. In the preceding examples,
Oracle Net waits for 60 seconds for each full connection to receive a response, after which it assumes that a failure occurred and retries the next address in the
ADDRESS_LIST
. Oracle Net retries the address list 3 times before it returns a failure message to the client. The
TRANSPORT_CONNECT_TIMEOUT
parameter establishes the time to wait to establish a TCP connection to the database server.
For SCAN, Oracle Net Services tries all three addresses (returned by the SCAN address) before returning a failure to the client. EZConnect with SCAN includes this connection failover feature.
This behavior is called Oracle Net connection failover. If an error is returned from a chosen address in the list, then Oracle Net Services tries the next address in the list until it is either successful or it has exhausted all addresses in its list.
Client-Side Connection Configuration for Older Clients
In addition to client-side load balancing, Oracle Net Services include connection
failover
. If an error is returned from the chosen address in the list, Oracle Net Services tries the next address in the list until it is either successful or it has exhausted all addresses in its list. For SCAN, Oracle Net Services tries all three addresses before returning a failure to the client. EZConnect with SCAN includes this connection failover feature.
To increase availability, you can specify a timeout that specifies how long Oracle Net waits for a response from the listener before returning an error. The method of setting this timeout parameter depends on the type of client access. Oracle Net maintains these parameters for backward compatibility.
This section includes the following topics:
•
•
JDBC-Thin Clients
You can avoid delays by setting the oracle.net.ns.SQLnetDef.TCP_CONNTIMEOUT_STR
property, as follows:
Properties prop = new Properties (); prop.put (oracle.net.ns.SQLnetDef.TCP_CONNTIMEOUT_STR,
Workload Management with Dynamic Database Services 5-3
Connection Load Balancing
"" + (1 * 1000)); // 1 second dbPools[ poolIndex ].setConnectionProperties ( prop );
The parameter value is specified in milliseconds. Therefore, it is possible to reduce the timeout to 500Ms if the application retries connecting.
OCI Clients
For OCI clients, create a local sqlnet.ora
file on the client side.
Configure the connection timeout in this file by adding the following line: sqlnet.outbound_connect_timeout = number_of_seconds
The granularity of the timeout value for the OCI client is in seconds. The sqlnet.ora
file affects all connections using this client.
Note:
Do not configure the connection timeout in the sqlnet.ora
file on the server.
Related Topics:
Oracle Call Interface Programmer's Guide
Client-Side Load Balancing
Client-side load balancing is defined in your client connection definition
( tnsnames.ora
file, for example) by setting the parameter
LOAD_BALANCE=ON
.
When you set this parameter to
ON
, Oracle Database randomly selects an address in the address list, and connects to that node's listener. This balances client connections across the available SCAN listeners in the cluster.
If you configured SCAN for connection requests, then client-side load balancing is not relevant for those clients that support SCAN access. When clients connect using
SCAN, Oracle Net automatically balances the load of client connection requests across the three IP addresses you defined for the SCAN, unless you are using EZConnect.
The SCAN listener redirects the connection request to the local listener of the instance that is least loaded (if
-clbgoal
is set to
SHORT
) and provides the requested service.
When the listener receives the connection request, the listener connects the user to an instance that the listener knows provides the requested service. To see what services a listener supports, run the lsnrctl services
command.
When clients connect using SCAN, Oracle Net automatically load balances client connection requests across the three IP addresses you defined for the SCAN, unless you are using EZConnect.
If you are using clients that do not support SCAN (for example, the client version is pre-Oracle Database 11g release 2 (11.2)), then, to use SCAN you must change the client tnsnames.ora
to include the SCAN VIPs, and set
LOAD_BALANCE=ON
to balance requests across the VIPs. For example:
Sales.example.com=(DESCRIPTION=
(ADDRESS_LIST=(LOAD_BALANCE=ON)(FAILOVER=ON)
(ADDRESS=(PROTOCOL=TCP)(HOST=172.22.67.192)(PORT=1521))
(ADDRESS=(PROTOCOL=TCP)(HOST=172.22.67.193)(PORT=1521))
(ADDRESS=(PROTOCOL=TCP)(HOST=172.22.67.194)(PORT=1521))
5-4 Oracle Real Application Clusters Administration and Deployment Guide
Load Balancing Advisory
(CONNECT_DATA=(SERVICE_NAME=salesservice.example.com))
))
Note:
If your database is not Oracle Database 11g release 2 (11.2), or later, and you want to use SCAN, then you must add SCAN VIPs to the
REMOTE_LISTENER parameter to enable correct listener cross-registration.
Related Topics:
Oracle Database Reference
Load Balancing Advisory
This section describes the load balancing advisory under the following topics:
•
Overview of the Load Balancing Advisory
•
Configuring Your Environment to Use the Load Balancing Advisory
•
Load Balancing Advisory FAN Events
•
Monitoring Load Balancing Advisory FAN Events
Overview of the Load Balancing Advisory
Load balancing distributes work across all of the available Oracle RAC database instances. Oracle recommends that applications use connection pools with persistent connections that span the instances that offer a particular service. When using persistent connections, connections are created infrequently and exist for a long duration. Work comes into the system with high frequency, borrows these connections, and exists for a relatively short duration. The load balancing advisory provides advice about how to direct incoming work to the instances that provide the optimal quality of service for that work. This minimizes the need to relocate the work later.
By using the Load Balancing Advisory and run-time connection load balancing goals, feedback is built in to the system. Work is routed to provide the best service times globally, and routing responds gracefully to changing system conditions. In a steady state, the system approaches equilibrium with improved throughput across all of the
Oracle RAC instances.
Standard architectures that can use the load balancing advisory include connection load balancing, transaction processing monitors, application servers, connection concentrators, hardware and software load balancers, job schedulers, batch schedulers, and message queuing systems. All of these applications can allocate work.
The load balancing advisory is deployed with key Oracle clients, such as a listener, the
JDBC universal connection pool, OCI session pool, Oracle WebLogic Server Active
GridLink for Oracle RAC, and the ODP.NET Connection Pools. Third-party applications can also subscribe to load balancing advisory events by using JDBC and
Oracle RAC FAN API or by using callbacks with OCI.
Workload Management with Dynamic Database Services 5-5
Load Balancing Advisory
Configuring Your Environment to Use the Load Balancing Advisory
You can configure your environment to use the load balancing advisory by defining service-level goals for each service for which you want to enable load balancing.
Configuring a service-level goal enables the load balancing advisory and the publishing of FAN load balancing events for that service. There are two types of service-level goals for run-time connection load balancing:
•
SERVICE_TIME
: Attempts to direct work requests to instances according to response time. Load balancing advisory data is based on elapsed time for work done in the service plus available bandwidth to the service. An example for the use of
SERVICE_TIME
is for workloads such as internet shopping where the rate of demand changes. The following example shows how to set the goal to
SERVICE_TIME
for connections using the online
service:
$ srvctl modify service -db db_unique_name -service online
-rlbgoal SERVICE_TIME -clbgoal SHORT
•
THROUGHPUT
: Attempts to direct work requests according to throughput. The load balancing advisory is based on the rate that work is completed in the service plus available bandwidth to the service. An example for the use of
THROUGHPUT is for workloads such as batch processes, where the next job starts when the last job completes. The following example shows how to set the goal to
THROUGHPUT for connections using the sjob
service:
$ srvctl modify service -db db_unique_name -service sjob
-rlbgoal THROUGHPUT -clbgoal LONG
Setting the run-time connection load balancing goal to
NONE
disables load balancing for the service. You can see the goal settings for a service in the data dictionary by querying the
DBA_SERVICES
,
V$SERVICES
, and
V$ACTIVE_SERVICES
views. You can also review the load balancing settings for a service using Oracle Enterprise
Manager.
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
Load Balancing Advisory FAN Events
The load balancing advisory FAN events provide metrics for load balancing algorithms.
The easiest way to take advantage of these events is to use the run-time connection load balancing feature of an Oracle integrated client such as JDBC, Universal
Connection Pool (or the deprecated Implicit Connection Cache), ODP.NET Connection
Pools, OCI session pools, or Oracle WebLogic Server Active GridLink for Oracle RAC.
Other client applications can take advantage of FAN programatically by using the
Oracle RAC FAN API to subscribe to FAN events and execute event-handling actions
upon receipt. Table 5-1 describes the load balancing advisory FAN event parameters.
5-6 Oracle Real Application Clusters Administration and Deployment Guide
Load Balancing Advisory
See Also:
Oracle Database JDBC Developer’s Guide
for more information about the Oracle
RAC FAN API
Table 5-1 Load Balancing Advisory FAN Events
Parameter Description
Version of the event record. Used to identify release changes.
VERSION
A load balancing advisory event is always of the
SERVICEMETRICS
event type.
EVENT_TYPE
The service name; matches the value of
NAME
in
DBA_SERVICES
.
SERVICE
DATABASE
The unique database supporting the service; matches the initialization parameter value for
DB_UNIQUE_NAME
, which defaults to the value of the initialization parameter
DB_NAME
.
The name of the instance that supports the service; matches the
ORACLE_SID
value.
INSTANCE
The percentage of work requests to send to this database instance.
PERCENT
FLAG
Indication of the service quality relative to the service goal. Valid values are
GOOD
,
VIOLATING
,
NO DATA
, and
BLOCKED
.
The local time zone to use when ordering notification events.
TIMESTAMP
Note:
The
INSTANCE
,
PERCENT
, and
FLAG
event parameters are generated for each instance offering the service. Each set of instance data is enclosed within braces (
{}
).
Related Topics:
Oracle Database JDBC Developer’s Guide
Monitoring Load Balancing Advisory FAN Events
You can use the following query against the internal queue table for load balancing advisory FAN events to monitor load balancing advisory events generated for an instance:
SET PAGES 60 COLSEP '|' LINES 132 NUM 8 VERIFY OFF FEEDBACK OFF
COLUMN user_data HEADING "AQ Service Metrics" FORMAT A60 WRAP
BREAK ON service_name SKIP 1
SELECT
Workload Management with Dynamic Database Services 5-7
Enabling Clients for Oracle RAC
TO_CHAR(enq_time, 'HH:MI:SS') Enq_time, user_data
FROM sys.sys$service_metrics_tab
ORDER BY 1 ;
The results of this query contain rows similar to the following:
02:56:05|SYS$RLBTYP('hr', 'VERSION=1.0 database=sales service=hr
{ {instance=sales_4 percent=38 flag=GOOD aff=TRUE}{instance=sales_1
percent=62 flag=GOOD aff=TRUE} } timestamp=2012-07-16 07:56:05')
Following is an example of a load balancing advisory event for the lba_serv
service offered on two instances ( orcl1
and orcl2
), as captured from Oracle Notification
Service using the Oracle RAC FAN API:
Notification Type: database/event/servicemetrics/lba_serv.example.com
VERSION=1.0 database=orcl service=lba_serv.example.com { {instance=orcl2
percent=50 flag=UNKNOWN aff=FALSE}{instance=orcl1 percent=50 flag=UNKNOWN
aff=FALSE} } timestamp=2012-07-06 13:19:12
Note:
The
SERVICMETRICS
events are not visible through the FAN callout mechanism.
Enabling Clients for Oracle RAC
Oracle has integrated FAN with many of the common client application environments that are used to connect to Oracle RAC databases. Therefore, the easiest way to use
FAN is to use an integrated Oracle Client.
The following sections discuss how FAN is integrated with Oracle Clients and how to enable FAN events for the several specific client development environments:
•
Overview of Oracle Integrated Clients and FAN
•
Enabling JDBC-Thin Clients for Fast Connection Failover
•
Enabling JDBC Clients for Run-time Connection Load Balancing
•
Configuring JDBC-Thin Clients for Application Continuity for Java
•
Configuring JDBC-Thin Clients for Transaction Guard
•
Enabling OCI Clients for Fast Connection Failover
•
Enabling OCI Clients for Run-time Connection Load Balancing
•
Configuring OCI Clients to use Transaction Guard
•
Enabling ODP.NET Clients to Receive FAN High Availability Events
•
Enabling ODP.NET Clients to Receive FAN Load Balancing Advisory Events
•
Configuring ODP.NET Clients to use Transaction Guard
Overview of Oracle Integrated Clients and FAN
The overall goals of FAN are to enable end-to-end, lights-out recovery of applications and load balancing based on real transaction performance.
5-8 Oracle Real Application Clusters Administration and Deployment Guide
Enabling Clients for Oracle RAC
Applications use the FAN high availability (HA) events to achieve very fast detection of failures, balancing of connection pools following failures, and distribution of connections again when the failed components are repaired.
The FAN events carrying load balancing advice help connection pools consistently deliver connections to available instances that provide the best service. FAN HA is integrated with the JDBC-thin and OCI drivers. FAN HA and FAN load balancing are both integrated with the JDBC Universal Connection Pool (and the deprecated Implicit
Connection Cache), the OCI session pools, the ODP.NET connection pool, and Oracle
WebLogic Server Active GridLink for Oracle RAC.
Due to the integration with FAN, Oracle integrated clients are more aware of the current status of an Oracle RAC cluster. This prevents client connections from waiting or trying to connect to instances or services that are no longer available. When instances start, Oracle RAC uses FAN to notify the connection pool so that the connection pool can create connections to the recently started instance and take advantage of the additional resources that this instance provides.
Oracle client drivers that are integrated with FAN can:
• Remove terminated connections immediately when a service is declared
DOWN
at an instance, and immediately when nodes are declared
DOWN
• Report errors to clients immediately when Oracle Database detects the
NOT
RESTARTING
state, instead of making the client wait while the service repeatedly attempts to restart
Oracle connection pools that are integrated with FAN can:
• Balance connections across all of the Oracle RAC instances when a service starts; this is preferable to directing the sessions that are defined for the connection pool to the first Oracle RAC instance that supports the service
• Balance work requests at run time using load balancing advisory events
The use of client drivers or connection pools and FAN requires that you properly configure the Oracle Notification Service to deliver the FAN events to the clients. In addition, for load balancing, configure database connection load balancing across all of the instances that provide the services used by the connection pool. Oracle recommends that you configure both client-side and server-side load balancing with
Oracle Net Services. If you use DBCA to create your database, then both client-side and server-side load balancing are configured by default.
Related Topics:
Oracle Net Services provides the ability to distribute client connections across the instances in an Oracle RAC configuration.
Enabling JDBC-Thin Clients for Fast Connection Failover
Enabling Fast Connection Failover (FCF) for Universal Connection Pool and Oracle
WebLogic Server Active GridLink for Oracle RAC enables the use of FAN HA and load balancing advisory events.
For Universal Connection Pool to use FAN, your application can use the JDBC development environment for either JDBC OCI or JDBC Thin clients. The Java
Database Connectivity Oracle Call Interface (JDBC/OCI) driver connection pooling
Workload Management with Dynamic Database Services 5-9
Enabling Clients for Oracle RAC functionality is part of the JDBC-thin client. This functionality is provided by the
OracleOCIConnectionPool
class.
To enable FCF for the JDBC-thin client, call the method setFastConnectionFailoverEnabled(true)
of the
OracleDataSource
class in the oracle.jdbc.pool
package before making the first getConnection() request. When you enable FCF for the JDBC-thin client, the failover property applies to every connection in the connection pool. Enabling FCF with JDBC-thin driver or
JDBC/OCI clients enables the connection pool to receive and react to all FAN events.
JDBC application developers can programmatically integrate with FAN by using a set of APIs introduced in Oracle Database 11g release 2 (11.2). The Oracle RAC FAN APIs enable application code to receive and respond to FAN event notifications sent by
Oracle RAC in the following ways:
• Listening for Oracle RAC service down, service up, and node down events
• Listening for load balancing advisory events and responding to them
Related Topics:
Oracle Database JDBC Developer’s Guide
Oracle Database 2 Day + Real Application Clusters Guide
Oracle Notification Service for JDBC-Thin Clients
FCF relies on Oracle Notification Service to propagate database events between the connection pool and the Oracle RAC database. At run time, the connection pool must be able to setup an Oracle Notification Service environment. Oracle Notification
Service ( ons.jar
) is included as part of the Oracle Client software. Oracle
Notification Service can be configured using either remote configuration or client-side
Oracle Notification Service daemon configuration. Remote Oracle Notification Service subscription offers the following advantages:
• Support for an All Java mid-tier software
• An Oracle Notification Service daemon is not necessary on the client system, so you do not have to manage this process
• Simple configuration by way of a
DataSource
property
Configuring FCF for JDBC/OCI and JDBC-Thin Driver Clients
You can enable FCF for Universal Connection Pool or Implicit Connection Cache.
Oracle recommends using the Universal Connection Pool for Java because the Implicit
Connection Cache is deprecated. You can also use Oracle WebLogic Server Active
GridLink for Oracle RAC.
This procedure explains how to enable FCF for JDBC. For JDBC/OCI clients, if you enable FCF, then do not use the method used with Oracle Database 11g release 2 (11.2) of enabling FAN for OCI clients (setting notification
to TRUE on the service), and do not configure TAF, either on the client or for the service. You can also configure
Application Continuity and Transaction Guard.
To enable FCF, you must first enable the Universal Connection Pool, as described in the following procedure:
1.
Create the connection pool and set setFastConnectionFailoverEnabled(true)
.
5-10 Oracle Real Application Clusters Administration and Deployment Guide
Enabling Clients for Oracle RAC
2.
The following example creates a connection pool and enables FCF. The ucp.jar
library must be included in the classpath of an application to use this example.
PoolDataSource pds = PoolDataSourceFactory.getPoolDataSource(); pds.setFastConnectionFailoverEnabled(true);
Determine the ports to use for Oracle Notification Service remote subscriptions.
Use the following command to view the Oracle Notification Service configuration on each node that is running Oracle Clusterware as in the following example: srvctl config nodeapps -onsonly
The output of this command lists the local and remote ports configured for Oracle
Notification Service.
Note:
Oracle Notification Service configuration should have been automatically completed during the Oracle Clusterware installation.
3.
Configure the remote Oracle Notification Service subscription.
When using the Universal Connection Pool, an application calls setONSConfiguration
for an
OracleDataSource
instance and specifies the nodes and port numbers to use. The port numbers used for each node are the same as the remote port displayed for each node in Step 2, as shown in the following example. The ons.jar
library must be included in the classpath of an application to use this example.
pds.setONSConfiguration("nodes=racnode1:6200,racnode2:6200");
4.
Applications that use remote Oracle Notification Service configuration must set the oracle.ons.oraclehome
system property to the location of
ORACLE_HOME before starting the application, for example: java -Doracle.ons.oraclehome=$ORACLE_HOME ...
Configure the connection URL.
A connection factory's connection URL must use the service name syntax when using FCF. The service name is used to map the connection pool to the service.
The following example demonstrates configuring the connection URL: pds.setConnectionFactoryClassName("oracle.jdbc.pool.OracleDataSource"); pds.setURL("jdbc:oracle:thin@//SCAN_name:service_name");...
Related Topics:
Oracle Database JDBC Developer’s Guide
Oracle Universal Connection Pool Developer’s Guide
Enabling JDBC Clients for Run-time Connection Load Balancing
Run-time connection load balancing requires the use of an Oracle JDBC driver and an
Oracle RAC database.
Workload Management with Dynamic Database Services 5-11
Enabling Clients for Oracle RAC
Oracle JDBC Universal Connection Pool and Oracle WebLogic Server Active GridLink for Oracle RAC leverage the load balancing functionality provided by an Oracle RAC database.
The Universal Connection Pool and Oracle WebLogic Server Active GridLink for
Oracle RAC are integrated to take advantage of Load Balancing Advisory information.
Oracle introduced the Universal Connection Pool for JDBC in Oracle Database 11g release 11.1.0.7.0. Consequently, Oracle deprecated the existing JDBC connection pool, the Implicit Connection Cache, which was introduced in Oracle Database 10g release 1 for use with Oracle RAC databases. In addition to Oracle Database 12c, you can also use the Universal Connection Pool with Oracle Database 10g or Oracle Database 11g.
Run-time connection load balancing requires that FCF is enabled and configured properly. In addition, the Oracle RAC load balancing advisory must be configured with service-level goals for each service used by the connection pool. The connection load balancing goal should be set to
SHORT
, for example: srvctl modify service -db db_unique_name -service service_name
-rlbgoal SERVICE_TIME -clbgoal SHORT
Related Topics:
Configuring FCF for JDBC/OCI and JDBC-Thin Driver Clients
You can enable FCF for Universal Connection Pool or Implicit
Connection Cache.
Oracle Universal Connection Pool Developer’s Guide
Configuring JDBC-Thin Clients for Application Continuity for Java
The Replay data source ( oracle.jdbc.replay.OracleDataSource
) is a JDBCthin data source that Application Continuity requires for Java.
This data source serves as the connection factory that produces new physical JDBC connections, for both Universal Connection Pool and Oracle WebLogic Server Active
GridLink for Oracle RAC data sources. The JDBC replay driver maintains a history of calls during a client conversation with Oracle Database 12c, in collaboration with
Oracle Database. Following any outage of the session caused by a loss of database service, planned or unplanned, under the direction of the database, the JDBC replay driver attempts to rebuild the non-transactional and transactional database session states, so that the outage appears as a delayed execution.
To use Application Continuity for Java and the JDBC replay driver, you must use an
Oracle Database 12c client and connect to an Oracle Database 12c database.
Application Continuity for Java is supported in the following configurations:
• JDBC applications using Oracle JDBC Replay data source and using neither
Universal Connection Pool or Oracle WebLogic Server Active GridLink—typical third-party, JDBC-based connection pools
• JDBC applications using Universal Connection Pool data sources—standalone or third-party application servers configured to use a Universal Connection Pool data source
• JDBC applications using only Oracle WebLogic Server Active GridLink but not
Universal Connection Pool data sources—typical Oracle WebLogic Server J2EE cases
5-12 Oracle Real Application Clusters Administration and Deployment Guide
Enabling Clients for Oracle RAC
To configure JDBC-thin clients to use the JDBC Replay Driver:
1.
2.
3.
Ensure that you are using an application that is certified for replay.
Use SRVCTL to create a service for use by the application, if one does not already exist. Set the
-failovertype
parameter to
TRANSACTION
and the
commit_outcome
parameter to
TRUE
for this service.
Configure the connection element using the replayDataSource
object, as shown in the following example: replayDataSource rds = PoolDataSourceFactory.getreplayDataSource(); rds.setConnnectionPoolName("replayExample"); rds.setONSConfiguration("nodes=racnode1:4200,racnode2:4200"); rds.setFastConnectionFailoverEnabled(true); rds.setConnectionFactoryClassName("oracle.jdbc.replay.OracleDataSource");
4.
Connection conn = replayDataSource.getConnection();
When connecting to the database, use a URL that can access all instances offering the service.
Related Topics:
Application Continuity masks many recoverable database outages
(when replay is successful) from applications and users by restoring the database session: the full session, including all states, cursors, variables, and the last transaction if there is one.
Creating Services for Application Continuity and Transaction Guard
To configure services for Application Continuity, when you create a service using SRVCTL, set the
-failovertype
parameter to
TRANSACTION
and
-commit_outcome
to
TRUE
.
Configuring FCF for JDBC/OCI and JDBC-Thin Driver Clients
You can enable FCF for Universal Connection Pool or Implicit
Connection Cache.
Oracle Database JDBC Developer’s Guide
Oracle Universal Connection Pool Developer’s Guide
See Also:
Oracle Database JDBC Developer’s Guide
for information about configuring
Transaction Guard without enabling Application Continuity
Configuring JDBC-Thin Clients for Transaction Guard
Transaction Guard provides a protocol and a generic tool for applications to use for atmost-once execution in case of planned and unplanned outages.
Applications use the logical transaction ID to determine the outcome of the last transaction open in a database session following an outage. Without Transaction
Guard, end users or applications that attempt to retry operations following outages can cause logical corruption by committing duplicate transactions or committing transactions out of order.
Workload Management with Dynamic Database Services 5-13
Enabling Clients for Oracle RAC
Related Topics:
Oracle Database JDBC Developer’s Guide
Oracle Database Development Guide
Oracle Call Interface Programmer's Guide
Enabling OCI Clients for Fast Connection Failover
OCI clients can enable FCF by registering to receive notifications for Oracle RAC high availability FAN events and responding when events occur. Using FCF improves the session failover response time in OCI applications and also removes connections to nonfunctioning instances from connection and session pools. FCF can be used in OCI applications that also use TAF, OCI drivers (including your own connection pools),
OCI connection pool, and OCI session pools. FAN is posted over the Oracle
Notification Service for both high availability and load balancing events.
To use FCF, you must use a service with FAN enabled. FAN is published over Oracle
Notification Service. Client applications can also register callbacks that are used whenever an event occurs. This reduces the time that it takes to detect a connection failure.
During
DOWN
event processing, OCI:
• Terminates affected connections at the client and returns an error
• Removes connections from the OCI connection pool and the OCI session pool— the session pool maps each session to a physical connection in the connection pool, and there can be multiple sessions for each connection
• Fails over the connection if you have configured TAF. If TAF is not configured, then the client only receives an error if the instance it is connected to fails.
If your application is using TAF, then you must enable the TAF properties for the service using SRVCTL or Oracle Enterprise Manager. Configure your OCI client applications to connect to an Oracle RAC database using the configured service.
Note:
OCI does not manage
UP
events.
Configuring FCF for OCI Clients
OCI applications must connect to an Oracle RAC instance to enable HA event notification. Furthermore, these applications must perform the following steps to configure FCF for an OCI client:
1.
Configure the service for your OCI connection pool to enable FAN, connection load balancing, and run-time connection load balancing, as shown in the following example:
$ srvctl modify service -db crm -service ociapp.example.com -notification TRUE
2.
3.
Link the application with a thread library.
After linking with the thread library, the applications can register a callback that is invoked whenever a FAN event occurs.
5-14 Oracle Real Application Clusters Administration and Deployment Guide
Enabling Clients for Oracle RAC
Related Topics:
Oracle Database Net Services Administrator's Guide
Oracle Call Interface Programmer's Guide
Enabling OCI Clients for Run-time Connection Load Balancing
As of Oracle Database 12c, OCI session pooling enables multiple threads of an application to use a dynamically managed set of pre-created database sessions.
In connection pooling, the pool element is a connection, but in session pooling, the pool element is a session. Oracle Database continually reuses the sessions in the session pool to form nearly permanent channels to the instances, thus saving the overhead of creating and closing sessions every time applications need them.
Run-time connection load balancing is enabled by default in an Oracle Database 11g release 11.1, or later, client communicating with a server of Oracle Database 10g release 10.2, or later. For Oracle RAC environments, session pools use service metrics
received from the Oracle RAC load balancing advisory 1 through Fast Application
Notification (FAN) events to balance application session requests. The work requests coming into the session pool can be distributed across the instances of Oracle RAC offering a service, using the current service performance.
Configuring OCI Clients to Receive Load Balancing Advisory FAN Events
For Oracle RAC environments, session pools use service metrics received from the
Oracle RAC load balancing advisory through Fast Application Notification (FAN) events to balance application session requests. To enable your application to receive the service metrics based on the service time, ensure that you configure FAN, the load balancing advisory goal (
-rlbgoal
parameter), and the connection load balancing goal (
-clbgoal
parameter) for a service that is used by the session pool, as shown in the following example:
$ srvctl modify service -db crm -service ociapp.example.com -rlbgoal SERVICE_TIME
-clbgoal SHORT -notification TRUE
Related Topics:
Oracle Call Interface Programmer's Guide
Configuring OCI Clients to use Transaction Guard
OCI supports FAN messages and Transaction Guard. FAN is designed to quickly notify an OCI-based application of outages at the node, database, instance, service, and public network levels.
Once notified of the failure, an application can leverage Transaction Guard to reliably determine the outcome of the last in-flight transaction.
Transaction Guard avoids the costs of ambiguous errors that lead to user frustration, customer support calls, and lost opportunities. Transaction Guard is safer and performs better, with lower overheads, than home grown solutions for a known outcome.
1
Run-time connection load balancing is basically routing work requests to sessions in a session pool that can best serve the work. It comes into effect when selecting a session from an existing session pool. Thus, run-time connection load balancing is a very frequent activity.
Workload Management with Dynamic Database Services 5-15
Enabling Clients for Oracle RAC
Related Topics:
The Oracle RAC high availability framework monitors a database and its services and sends event notifications using Fast Application
Notification (FAN).
Enabling Clients for Oracle RAC
Oracle Call Interface Programmer's Guide
Enabling ODP.NET Clients to Receive FAN High Availability Events
ODP.NET connection pools can subscribe to FAN HA notifications that indicate when nodes, services, and service members are down.
After a
DOWN
event, Oracle Database cleans up sessions in the connection pool that go to the instance and ODP.NET proactively removes connections that are no longer valid. ODP.NET establishes additional connections to existing Oracle RAC instances if the removal of invalid connections reduces the total number of connections to below the value for the
Min Pool Size
parameter.
When connecting to Oracle Database 12c and later, ODP.NET uses Oracle Notification
Service, rather than Advanced Queuing.
Enable Fast Connection Failover for ODP.NET connection pools by subscribing to
FAN high availability events. To enable Fast Connection Failover, include "
HA
Events=true
" and " pooling=true
" (the default value) in the connection string, as shown in the following example where
user_name
is the name of the database user and
password
is the password for that user: con.ConnectionString =
"User Id=user_name;Password=password;Data Source=odpnet;" +
"Min Pool Size=10;Connection Lifetime=120;Connection Timeout=60;" +
"HA Events=true;Incr Pool Size=5;Decr Pool Size=2";
Related Topics:
Oracle Data Provider for .NET Developer's Guide for Microsoft Windows
Enabling ODP.NET Clients to Receive FAN Load Balancing Advisory Events
When connecting to Oracle Database 12c and later, ODP.NET uses Oracle Notification
Service, rather than Advanced Queuing.
Use the following procedure to enable ODP.NET clients or applications to receive
FAN load balancing advisory events:
1.
Enable Oracle Notification Service notifications by using SRVCTL, and set the run-time load balancing goal, as shown in the following example:
2.
3.
$ srvctl modify service -db crm -service odpapp.example.com
-notification TRUE -clbgoal LONG -rlbgoal SERVICE_TIME
Ensure Oracle Notification Service (ONS) is configured for FAN events including run-time load balancing advice.
To take advantage of load balancing events with ODP.NET connection pools, set the load balancing attribute in the ConnectionString to
TRUE
(the default is
FALSE
). You can do this at connect time. This only works if you are using connection pools, or when the pooling attribute is set to
TRUE
which is the default.
5-16 Oracle Real Application Clusters Administration and Deployment Guide
Distributed Transaction Processing in Oracle RAC
The following example demonstrates how to configure the ConnectionString to enable load balancing, where
user_name
is the name of the user and
password
is the password: con.ConnectionString =
"User Id=user_name;Password=password;Data Source=odpapp;" +
"Min Pool Size=10;Connection Lifetime=120;Connection Timeout=60;" +
"Load Balancing=true;Incr Pool Size=5;Decr Pool Size=2";
Note:
ODP.NET does not support connection redistribution when a node starts (UP events). However, if you have enabled failover on the server-side, then
ODP.NET can migrate connections to newly available instances.
Related Topics:
Modifies service configuration.
Oracle Data Provider for .NET Developer's Guide for Microsoft Windows
Configuring ODP.NET Clients to use Transaction Guard
ODP.NET supports FAN messages and Transaction Guard. FAN is designed to quickly notify an ODP.NET-based application of outages at the node, database, instance, service, and public network levels.
Once notified of the failure, an application can leverage Transaction Guard to reliably determine the outcome of the last in-flight transaction.
Transaction Guard avoids the costs of ambiguous errors that lead to user frustration, customer support calls, and lost opportunities. Transaction Guard is safer and performs better, with lower overheads, than home grown solutions for a known outcome.
Related Topics:
The Oracle RAC high availability framework monitors a database and its services and sends event notifications using Fast Application
Notification (FAN).
Creating Services for Application Continuity and Transaction Guard
To configure services for Application Continuity, when you create a service using SRVCTL, set the
-failovertype
parameter to
TRANSACTION
and
-commit_outcome
to
TRUE
.
Oracle Data Provider for .NET Developer's Guide for Microsoft Windows
Distributed Transaction Processing in Oracle RAC
The X/Open Distributed Transaction Processing (DTP) architecture defines a standard architecture or interface that enables multiple application programs (APs) to share
Workload Management with Dynamic Database Services 5-17
Distributed Transaction Processing in Oracle RAC resources provided by multiple, and possibly different, resource managers (RMs). It coordinates the work between APs and RMs into global transactions.
The following sections discuss how Oracle RAC supports global (XA) transactions and
DTP processing:
•
Overview of XA Transactions and Oracle RAC
•
Using Global Transactions and XA Affinity for XA Transactions
•
Using Services with XA Transactions on Oracle RAC
•
Configuring Services for XA Applications
•
Relocating Services in Administrator-Managed Databases
Overview of XA Transactions and Oracle RAC
A global (XA) transactioncan span Oracle RAC instances by default, allowing any application that uses the Oracle XA library to take full advantage of the Oracle RAC environment to enhance the availability and scalability of the application.
GTXn background processes support XA transactions in an Oracle RAC environment.
The
GLOBAL_TXN_PROCESSES
initialization parameter, which is set to
1
by default, specifies the initial number of GTXn background processes for each Oracle RAC instance. Use the default value for this parameter clusterwide to allow distributed transactions to span multiple Oracle RAC instances. Using the default value allows the units of work performed across these Oracle RAC instances to share resources and act as a single transaction (that is, the units of work are tightly coupled). It also allows 2PC requests to be sent to any node in the cluster.
Before Oracle RAC 11g release 1 (11.1), the way to achieve tight coupling in Oracle
RAC was to use distributed transaction processing (DTP) services, that is, services whose cardinality (one) ensured that all tightly-coupled branches landed on the same instance—regardless of whether load balancing was enabled. If the XA application does not use suspend and resume on the same transaction branch, and does not issue savepoints that span branches, then tightly coupled XA transactions no longer require the special type of singleton services to be deployed on Oracle RAC databases. If your application cannot determine whether a transaction branch has been suspended and resumed, then the application must continue to use DTP services or preferably use XA affinity.
XA affinity (placing all branches of the same XA transaction at the same Oracle RAC instance) is a requirement when suspending and resuming the same XA branch or if using savepoints across branches. It also provides much better performance because different transactions can be balanced. XA affinity is available with Oracle WebLogic
Server Active GridLink for Oracle RAC, JDBC Universal Connection Pool, and Oracle
Tuxedo.
Note:
Occasionally, transaction processing monitors continue to require either XA affinity or DTP services because the applications that use them suspend and resume the same branch or use save points.
An external transaction manager, such as Oracle Services for Microsoft Transaction
Server (OraMTS), coordinates XA transactions. However, an internal Oracle
5-18 Oracle Real Application Clusters Administration and Deployment Guide
Distributed Transaction Processing in Oracle RAC transaction manager coordinates distributed SQL transactions. They can both use singleton services or uniform services. Singleton services provide XA affinity and can be drained for maintenance, taking advantage of global transactions.
Related Topics:
Using Global Transactions and XA Affinity for XA Transactions
To provide improved application performance with distributed transaction processing (DTP) in Oracle RAC, you can take advantage of
XA affinity.
Oracle Database Reference
Using Global Transactions and XA Affinity for XA Transactions
To provide improved application performance with distributed transaction processing
(DTP) in Oracle RAC, you can take advantage of XA affinity.
Using XA affinity, you can direct all branches of a distributed transaction to a single instance in the cluster. To implement XA affinity you can use an application server that provides XA affinity, such as WebLogic Server and Universal Connection Pool. If your application server does not have XA affinity, then you can also use singleton services across Oracle RAC.
Connection pools at the application server tier that load balance across multiple connections to an Oracle RAC database use XA affinity to ensure that all tightlycoupled branches of a global distributed transaction run on only one Oracle RAC instance. When using a connection pool with XA affinity, your services using XA can span Oracle RAC. This is also true in distributed transaction environments using protocols such as X/Open Distributed Transaction Processing or the Microsoft
Distributed Transaction Coordinator.
To enhance the performance of distributed transactions, you use services to manage
DTP environments. A singleton service runs on one Oracle RAC instance at time in an
Oracle RAC database. This service still allows draining for maintenance, so has better high-availability characteristics than an older DTP service. To load balance across the cluster, it is better to have several groups of smaller application servers with each group directing its transactions to a single service, or set of services, than it is to have one or two larger application servers. Using singleton services, global distributed transactions performed through the services have their tightly-coupled branches running on a single Oracle RAC instance. This has the following benefits:
• The changes are available locally within one Oracle RAC instance when tightly coupled branches need information about changes made by each other
• Relocation and failover of services are fully supported using global transactions
• By using more singleton services than there are Oracle RAC instances, Oracle
Database can balance the load by services across all of the Oracle RAC database instances
Note:
The DTP service attribute or XA affinity is required, if the application suspend and resumes the same XA branch.
Workload Management with Dynamic Database Services 5-19
Distributed Transaction Processing in Oracle RAC
Using Services with XA Transactions on Oracle RAC
Most applications using XA on Oracle RAC can use uniform or (all preferred) services with XA affinity provided by the connection pool or transaction processing monitor.
The application may also use singleton services to provide XA affinity.
When using singleton services, to leverage all of the instances in a cluster, create one or more singleton services for each Oracle RAC instance that hosts distributed transactions. Choose different services for application servers to balance the workload among the Oracle RAC database instances. Because all of the branches of a distributed transaction are on one instance, you can leverage all of the instances to balance the load of many distributed transaction processing (DTP) transactions through multiple singleton services, thereby maximizing application throughput.
If you add or delete nodes from your cluster database, then you may have to identify and relocate services to ensure that you maintain optimum performance levels. Using singleton services, current work can complete. If you use DTP services, then current work is aborted.
You only need to use DTP services for XA applications that suspend and resume the same branch. When you are using DTP, the same approach applies as that for singletons, but you cannot drain the work when relocating services.
Configuring Services for XA Applications
To create distributed transaction processing (DTP) services for distributed transaction processing, perform the following steps:
1.
Create a singleton service using Oracle Enterprise Manager or SRVCTL.
For an administrator-managed database, define only one instance as the preferred instance. You can have as many available instances as you want, for example:
$ srvctl add service -db crm -service xa_01.example.com -preferred RAC01
-available RAC02,RAC03
2.
For a policy-managed database, specify the server pool to use, and set the cardinality of the service to
SINGLETON
, for example:
$ srvctl add service -db crm -service xa_01.example.com -serverpool dtp_pool
-cardinality SINGLETON
Set the DTP parameter (
-dtp
) for the service to
TRUE
(the default value is
FALSE)
. You can use Oracle Enterprise Manager or SRVCTL to modify the DTP property of the singleton service. The following example shows how to modify the xa_01.example.com
service using SRVCTL:
$ srvctl modify service -db crm -service xa_01.example.com -dtp TRUE
Note:
If the application does require DTP services, then use the
-dtp parameter. If not, then use the preceding example with no
-dtp
parameter.
Related Topics:
Adds services to a database and assigns them to instances.
5-20 Oracle Real Application Clusters Administration and Deployment Guide
Automatic Workload Repository
Modifies service configuration.
Relocating Services in Administrator-Managed Databases
Beginning with Oracle Real Application Clusters 11g release 1 (11.1), global transactions and XA affinity replace the need for distributed transaction processing
(DTP) services.
Most XA deployments should be using global transactions with XA affinity for improved load balancing and flexibility rather than the DTP attribute.
If the instance that provides a DTP service, for example
XA_01
, fails, then the service fails over in the same manner as any other service. Because there is a requirement that sessions exist on exactly one instance, however, the
-f
(force kill) option for database sessions always applies.
If services migrate to other instances, then you might have to force the relocation of the service back to the preferred instance after it is restarted to evenly re-balance the load on all of the available hardware. You can use data from the
GV
$ACTIVE_SERVICES
view to determine whether you need to relocate the DTP service.
Automatic Workload Repository
The Automatic Workload Repository (AWR) collects, processes, and maintains performance statistics for the database.
The gathered data can be displayed in both reports and views. If you use services with
your database, then AWR tracks
Metrics can be measured against a variety of units, including time, transactions, or database calls. For example, the number of database calls per second is a metric. Server generated alerts can be placed on these metrics when they exceed or fail to meet userspecified thresholds. The database or system administrator can then respond, for example, by:
• Using the Oracle Database Resource Manager to configure the service level for one service to have priorities relative to other services
• Stopping overloaded processes
• Modifying a service level requirement
• Implementing recovery scenarios in response to service quality changes
Using AWR metrics and performance alerts enables you to maintain continued service availability despite service level changes. It also enables you to measure the quality of service provided by the database services.
The AWR ensures that the Oracle Clusterware workload management framework and the database resource manager have persistent and global representations of performance data. This information helps Oracle Database schedule job classes by service and to assign priorities to consumer groups. If necessary, you can rebalance workloads manually with either Oracle Enterprise Manager or SRVCTL. You can also disconnect a series of sessions, but leave the service running.
Workload Management with Dynamic Database Services 5-21
Measuring Performance by Service Using the Automatic Workload Repository
Note:
Oracle does not recommend using the DBMS_SERVICE package for use with services used by an Oracle RAC database. Use SRVCTL or Oracle Enterprise
Manager to create database services for Oracle RAC.
Related Topics:
Oracle Database 2 Day + Performance Tuning Guide
Oracle Database Performance Tuning Guide
Oracle Database PL/SQL Packages and Types Reference
Measuring Performance by Service Using the Automatic Workload
Repository
Services add a new dimension for performance tuning because workloads are visible and measurable, and therefore resource consumption and wait times are attributable by application.
Tuning by using "service and SQL" replaces tuning by "session and SQL" in the majority of systems where all sessions are anonymous and shared.
The AWR maintains performance statistics that include information about response time, throughput, resource consumption, and wait events for all services and work that a database performs. Oracle Database also maintains metrics, statistics, wait events, wait classes, and SQL-level traces for services. You can optionally augment these statistics by defining modules within your application to monitor certain statistics. You can also define the actions within those modules that business critical transactions should execute in response to particular statistical values.
Enable module and action monitoring using the
DBMS_MONITOR
PL/SQL package.
For example, for connections that use the erp
service, the following command enables monitoring for the exceptions pay
action in the payroll
module:
EXECUTE DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE(SERVICE_NAME => 'ERP',
MODULE_NAME=> 'PAYROLL', ACTION_NAME => 'EXCEPTIONS PAY');
For connections that use the erp
service, the following command enables monitoring for all actions in the payroll
module:
EXECUTE DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE(SERVICE_NAME => 'ERP',
MODULE_NAME=> 'PAYROLL', ACTION_NAME => NULL);
Use the
DBA_ENABLED_AGGREGATIONS
view to verify that you have enabled monitoring for application modules and actions.
Statistics aggregation and tracing by service are global in scope for Oracle RAC databases. In addition, these statistic aggregations are persistent across instance restarts and service relocations for both Oracle RAC and noncluster Oracle databases.
The service, module, and action names are visible in
V$SESSION
,
V
$ACTIVE_SESSION_HISTORY
, and
V$SQL
views. The call times and performance statistics are visible in
V$SERVICE_STATS
,
V$SERVICE_EVENT
,
V
$SERVICE_WAIT_CLASS
,
V$SERVICEMETRIC
, and
V$SERVICEMETRIC_HISTORY
.
When you enable statistics collection for an important transaction, you can see the call
5-22 Oracle Real Application Clusters Administration and Deployment Guide
Automatic Workload Repository Service Thresholds and Alerts speed for each service, module, and action name at each database instance using the
V
$SERV_MOD_ACT_STATS
view.
The following sample SQL*Plus script provides service quality statistics for a five second interval. You can use these service quality statistics to monitor the quality of a service, to direct work, and to balance services across Oracle RAC instances:
SET PAGESIZE 60 COLSEP '|' NUMWIDTH 8 LINESIZE 132 VERIFY OFF FEEDBACK OFF
COLUMN service_name FORMAT A20 TRUNCATED HEADING 'Service'
COLUMN begin_time HEADING 'Begin Time' FORMAT A10
COLUMN end_time HEADING 'End Time' FORMAT A10
COLUMN instance_name HEADING 'Instance' FORMAT A10
COLUMN service_time HEADING 'Service Time|mSec/Call' FORMAT 999999999
COLUMN throughput HEADING 'Calls/sec'FORMAT 99.99
BREAK ON service_name SKIP 1
SELECT
service_name
, TO_CHAR(begin_time, 'HH:MI:SS') begin_time
, TO_CHAR(end_time, 'HH:MI:SS') end_time
, instance_name
, elapsedpercall service_time
, callspersec throughput
FROM
gv$instance i
, gv$active_services s
, gv$servicemetric m
WHERE s.inst_id = m.inst_id
AND s.name_hash = m.service_name_hash
AND i.inst_id = m.inst_id
AND m.group_id = 10
ORDER BY
service_name
, i.inst_id
, begin_time ;
Automatic Workload Repository Service Thresholds and Alerts
Service level thresholds enable you to compare actual service levels against required levels of service. This provides accountability for the delivery or the failure to deliver an agreed service level. The end goal is a predictable system that achieves service levels. There is no requirement to perform as fast as possible with minimum resource consumption; the requirement is to meet the quality of service.
AWR enables you to explicitly specify two performance thresholds for each service: the response time for calls (
ELAPSED_TIME_PER_CALL
), and the CPU time for calls
(
CPU_TIME_PER_CALL
). The response time threshold indicates that the elapsed time for each user call for each service should not exceed a certain value, and the CPU time for calls threshold indicates that the time spent using the CPU for each call for each service should not exceed a certain value. Response time is a fundamental measure that reflects all delays and faults that might be blocking the call from running on behalf of the user. Response time can also indicate differences in node power across the nodes of an Oracle RAC database.
You must set these thresholds on each instance of an Oracle RAC database. The elapsed time and CPU time are calculated as the moving average of the elapsed, server-side call time. The AWR monitors the elapsed time and CPU time and publishes AWR alerts when the performance exceeds the thresholds. You can schedule actions using Oracle Enterprise Manager jobs for these alerts, or you can schedule actions to occur programmatically when the alert is received. You can respond to these alerts by changing the priority of a job, stopping overloaded processes, or by
Workload Management with Dynamic Database Services 5-23
Automatic Workload Repository Service Thresholds and Alerts relocating, starting or stopping a service. This permits you to maintain service availability despite changes in demand.
This section includes the following topics:
•
Example of Services and Thresholds Alerts
•
Enable Service_ Module_ and Action Monitoring
Example of Services and Thresholds Alerts
In this scenario, you need to check the thresholds for the payroll service. You can use the AWR report to get this information. You should compare the results from reports run over several successive intervals during which time the system is running optimally. For example, assume that for servers accessed by a payroll application, the
AWR report runs each Thursday during the peak usage times of 1:00 p.m. to 5:00 p.m.
The AWR report contains the response time, or elapsed database time, and the CPU consumption time, or CPU time, for calls for each server, including the payroll service. The AWR report also provides a breakdown of the work done and the wait times that are contributing to the response times.
Using
DBMS_MONITOR
, you set a warning threshold for the elapsed time per call for the payroll
service at 0.5 seconds (500000 microseconds). You also set a critical threshold for the elapsed time per call for the payroll
service at 0.75 seconds (750000 microseconds).
In this example, thresholds are added for the payroll
service as follows:
EXECUTE DBMS_SERVER_ALERT.SET_THRESHOLD(
METRICS_ID => DBMS_SERVER_ALERT.ELAPSED_TIME_PER_CALL
, warning_operator => DBMS_SERVER_ALERT.OPERATOR_GE
, warning_value => '500000'
, critical_operator => DBMS_SERVER_ALERT.OPERATOR_GE
, critical_value => '750000'
, observation_period => 30
, consecutive_occurrences => 5
, instance_name => NULL
, object_type => DBMS_SERVER_ALERT.OBJECT_TYPE_SERVICE
, object_name => 'payroll');
You can verify the threshold configuration is set on all the instances using the following
SELECT
statement:
SELECT METRICS_NAME, INSTANCE_NAME, WARNING_VALUE, CRITICAL_VALUE,
OBSERVATION_PERIOD FROM dba_thresholds ;
Enable Service, Module, and Action Monitoring
You can enable performance data tracing for important modules and actions within each service. The performance statistics are available in the
V$SERV_MOD_ACT_STATS view. For example, you might decide to set the following:
• For the
ERP
service, enable monitoring for the exceptions pay
action in the payroll
module.
• For the
ERP
service, enable monitoring for the all actions in the payroll
module.
• For the
HOT_BATCH
service, enable monitoring for all actions in the posting module.
5-24 Oracle Real Application Clusters Administration and Deployment Guide
Using Oracle Services
The following commands show how to enable the module and action monitoring for the services:
EXECUTE DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE(service_name => 'erp', module_name=>
'payroll', action_name => 'exceptions pay');
EXECUTE DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE(service_name => 'erp', module_name=>
'payroll');
EXECUTE DBMS_MONITOR.SERV_MOD_ACT_STAT_ENABLE(service_name => 'hot_batch', module_name =>'posting');
To verify monitoring is enabled for the service, module, and actions, use the following
SELECT
statement:
COLUMN AGGREGATION_TYPE FORMAT A21 TRUNCATED HEADING 'AGGREGATION'
COLUMN PRIMARY_ID FORMAT A20 TRUNCATED HEADING 'SERVICE'
COLUMN QUALIFIER_ID1 FORMAT A20 TRUNCATED HEADING 'MODULE'
COLUMN QUALIFIER_ID2 FORMAT A20 TRUNCATED HEADING 'ACTION'
SELECT * FROM DBA_ENABLED_AGGREGATIONS ;
The output is similar to the following:
AGGREGATION SERVICE MODULE ACTION
------------ -------------------- ---------- -------------
SERVICE_MODULE_ACTION erp payroll exceptions pay
SERVICE_MODULE erp payroll
SERVICE_MODULE hot_batch posting
Using Oracle Services
To manage workloads or a group of applications, you can define services that you assign to a particular application or to a subset of an application's operations. You can also group work by type under services. For example, online users can use one service, while batch processing can use another and reporting can use yet another service to connect to the database.
Oracle recommends that all users who share a service have the same service level requirements. You can define specific characteristics for services and each service can represent a separate unit of work. There are many options that you can take advantage of when using services. Although you do not have to implement these options, using them helps optimize application performance.
Service Deployment Options
This section describes the following service deployment topics:
•
Service Usage in an Oracle RAC Database
•
•
•
Restricted Service Registration
Service Usage in an Oracle RAC Database
Services provide location transparency. A service name can identify multiple database instances, and an instance can belong to multiple services. Several database features use services for an Oracle RAC database:
This section includes the following topics:
Workload Management with Dynamic Database Services 5-25
Service Deployment Options
•
Oracle Clusterware Resources for a Service
•
Database Resource Manager Consumer Group Mappings for Services
•
Performance Monitoring by Service with AWR
•
Parallel Operations and Services
•
Oracle Clusterware Resources for a Service
Resource profiles are automatically created when you define a service. A resource profile describes how Oracle Clusterware should manage the service and which instance the service should failover to if the preferred instance stops. Resource profiles also define service dependencies for the instance and the database. Due to these dependencies, if you stop a database, then the instances and services are automatically stopped in the correct order.
Database Resource Manager Consumer Group Mappings for Services
Services are integrated with Oracle Resource Manager, which enables you to restrict the resources that users use to connect to an instance by using a service. Oracle
Resource Manager enables you to map a consumer group to a service so that users who connect to an instance using that service are members of the specified consumer group. Oracle Resource Manager operates at an instance level.
Performance Monitoring by Service with AWR
The metric data generated by Automatic Workload Repository (AWR) is organized into various groups, such as event, event class, session, service, and tablespace metrics.
Typically, you view the AWR data using Oracle Enterprise Manager or AWR reports.
Related Topics:
Oracle Database Performance Tuning Guide
Parallel Operations and Services
By default, in an Oracle RAC environment, a SQL statement executed in parallel can run across all of the nodes in the cluster. For this cross-node or inter-node parallel execution to perform well, the interconnect in the Oracle RAC environment must be sized appropriately because inter-node parallel execution may result in a lot of interconnect traffic. To limit inter-node parallel execution, you can control parallel execution in an Oracle RAC environment using the
PARALLEL_FORCE_LOCAL initialization parameter. By setting this parameter to
TRUE
, the parallel execution servers can only execute on the same Oracle RAC node where the SQL statement was started.
Services are used to limit the number of instances that participate in a parallel SQL operation. When the default database service is used, the parallel SQL operation can run on all available instances. You can create any number of services, each consisting of one or more instances. When a parallel SQL operation is started, the parallel execution servers are only spawned on instances which offer the specified service used in the initial database connection.
PARALLEL_INSTANCE_GROUP
is an Oracle RAC parameter that, when used with services, lets you restrict parallel query operations to a limited number of instances.To
restrict parallel query operations to a limited number of instances, set the
5-26 Oracle Real Application Clusters Administration and Deployment Guide
Service Deployment Options
PARALLEL_INSTANCE_GROUP
initialization parameter to the name of a service. This does not affect other parallel operations such as parallel recovery or the processing of
GV$
queries.
Oracle Streams and Oracle RAC
Oracle Streams takes advantage of Oracle RAC features.
When Oracle Streams is configured in an Oracle RAC environment, each queue table has an owning instance. If the instance that hosts a queue table fails, another instance in the Oracle RAC database becomes the owning instance for the queue table, allowing
Oracle Streams to continue operating.
Also, on an Oracle RAC database, a service is created for each buffered queue. This service always runs on the owner instance of the destination queue and follows the ownership of this queue if the ownership switches because of instance startup, instance shutdown, and so on. This service is used by queue-to-queue propagations.
Related Topics:
Oracle Streams Concepts and Administration
Service Characteristics
When you create new services for your database, you should define the automatic workload management characteristics for each service. The characteristics of a service include:
•
•
•
•
•
•
•
Load Balancing Advisory Goal for Run-time Connection Load Balancing
•
Connection Load Balancing Goal
•
Distributed Transaction Processing
•
Failing Over OCI Clients with TAF
Service Name
Each service has a service name. The service name is used by clients to connect to one or more instances. The service name must be unique throughout your system.
Service Edition
Edition-based redefinition of database objects enables you to upgrade an application's objects while these objects are in use. You can set the edition attribute of a database service when you create it, or modify an existing service to set the edition. When you set the service edition, connections that use this service use this edition as the initial session edition. If the service does not specify the edition name, then the initial session edition is the database default edition.
Workload Management with Dynamic Database Services 5-27
Service Deployment Options
You can set the service edition using SRVCTL, as follows:
$ srvctl modify service –db hr –s crmsrv –edition e2
Service Management Policy
When you use Oracle Clusterware to manage your database, you can configure startup options for each individual database service when you add the service using the srvctl add service
command with the
-policy
parameter.
If you set the management policy for a service to
AUTOMATIC
(the default), then the service starts automatically when you start the database with SRVCTL. If you set the management policy to
MANUAL
, then the service does not automatically start, and you must manually start it with SRVCTL. A
MANUAL
setting does not prevent Oracle
Clusterware from monitoring the service when it is running and restarting it if a failure occurs. Before Oracle RAC 11g release 2 (11.2), all services worked as though they were defined with a
MANUAL
management policy.
Using CRSCTL to stop and restart Oracle Clusterware is treated as a failure and the service is restarted if it was previously running.
Note:
When you use automatic services in an administrator-managed database, during planned database startup, services may start on the first instances to start rather than their preferred instances, provided that the started instances are in the (combined) preferred and available services list.
Related Topics:
Adds services to a database and assigns them to instances.
Database Role for a Service
If you configured Oracle Data Guard in your environment, then you can define a role for services when you add or modify a service using SRVCTL and the
-role parameter with the appropriate command.
When you specify a role for a service, Oracle Clusterware automatically starts the service only when the database role matches the role you specified for the service.
Valid roles are
PRIMARY
,
PHYSICAL_STANDBY
,
LOGICAL_STANDBY
, and
SNAPSHOT_STANDBY
and you can specify more than one role for a service.
Note:
The service role only controls automatic startup of services. Using SRVCTL to manually start a service will succeed even if the roles do not match.
Redo Apply (physical standby database) can run on all or some standby instances that you can configure. This enables Redo Apply performance to scale, if necessary, by adding additional standby instances.
If multiple databases in the cluster offer the same service name, then Oracle RAC balances connections to that service across all such databases. This is useful for standby and active Oracle Data Guard databases, but if you want client connections to
5-28 Oracle Real Application Clusters Administration and Deployment Guide
Service Deployment Options a service to be directed to a particular database, then the service name must be unique within the cluster (not offered by any other database).
Related Topics:
Oracle Data Guard Concepts and Administration
Instance Preference
When you define a service for an administrator-managed database, you define which instances normally support that service using SRVCTL with the
-preferred parameter.
These are known as the preferred instances. You can also define other instances to support a service if the service's preferred instance fails using SRVCTL with the
available
parameter. These are known as available instances.
When you specify preferred instances, you are specifying the number of instances on which a service normally runs. This is the maximum cardinality of the service. Oracle
Clusterware attempts to ensure that the service always runs on the number of instances for which you have configured the service. Afterwards, due to either instance failure or planned service relocations, a service may be running on an available instance.
If an instance fails, then you cannot control to which available instance Oracle
Clusterware relocates the services if there are multiple instances in the list. During a planned operation, however, you can manually direct the service to any instance in either the preferred or the available list not currently offering the service.
When a service moves to an available instance, Oracle Database does not move the service back to the preferred instance when the preferred instance restarts because:
• The service is running on the desired number of instances.
• Maintaining the service on the current instance provides a higher level of service availability.
• Not moving the service back to the initial preferred instance prevents a second outage.
You can, however, easily automate fail back to the preferred instance by using FAN callouts.
Related Topics:
Tools for Administering Oracle RAC
Server Pool Assignment
When you define services for a policy-managed database, you assign the service to a server pool in which the database is hosted using SRVCTL with the
-serverpool parameter.
You can define the service as either
UNIFORM
(running on all instances in the server pool) or
SINGLETON
(running on only one instance in the server pool) using the
cardinality
parameter. For singleton services, Oracle RAC chooses on which instance in the server pool the service is active. If that instance fails, then the service fails over to another instance in the server pool. A service can only run in one server pool and Oracle recommends that every server pool has at least one service.
Workload Management with Dynamic Database Services 5-29
Service Deployment Options
Note:
Oracle Database Quality of Service Management (Oracle Database QoS
Management) manages singleton services in a server pool, if the maximum size of that server pool is one.
Related Topics:
Tools for Administering Oracle RAC
Load Balancing Advisory Goal for Run-time Connection Load Balancing
With run-time connection load balancing, applications can use load balancing advisory events to provide better service to users. Oracle JDBC, Oracle Universal
Connection Pool for Java, OCI session pool, ODP.NET, and Oracle WebLogic Server
Active GridLink for Oracle RAC clients are automatically integrated to take advantage of load balancing advisory events. The load balancing advisory informs the client about the current service level that an instance is providing for a service. To enable the load balancing advisory, use SRVCTL with the
-rlbgoal
parameter when creating or modifying the service.
The load balancing advisory also recommends how much of the workload should be sent to that instance. The goal determines whether connections are made to the service based on best service quality (how efficiently a single transaction completes) or best throughput (how efficiently a complete job or long-running query completes).
Connection Load Balancing Goal
Oracle Net Services provides connection load balancing to enable you to spread user connections across all of the instances that are supporting a service.
For each service, you can use SRVCTL to define the method you want the listener to use for load balancing by setting the connection load balancing goal, specified with the
-clbgoal
parameter. Connections are classified as
LONG
(such as connection pools and SQL*FORMS), which tells the listener to use session count, or
SHORT
, which tells the listener to use response-time or throughput statistics.
If load balancing advisory is enabled (the
-rlbgoal
parameter does not equal
NONE
), then connection load balancing attempts to use load balancing advisory (whether it is set to
SHORT
or
LONG
). If load balancing advisory is set to
SHORT
, then it will use the
GOODNESS
value of a service to try to prevent all connection requests from going to one instance. If load balancing advisory is set to
LONG
, then it uses run queue length
if the service is non-uniform, or session count
if there is uniform service distribution.
Distributed Transaction Processing
applications have unique requirements. Oracle provides global transactions across Oracle RAC. For best performance, use XA affinity (all branches at the same instance) for most transactions, and global transactions when needed. You can use XA affinity with connection pools, such as Universal Connection Pools and WebLogic
Server. You can also use singleton services that you create using SRVCTL. Use
SRVCTL, as well, to set the distributed transaction processing parameter (
-dtp
) to
TRUE
if you are suspending and resuming the same Oracle XA branch. Do not use this in general, however, because it does not offer rolling planned maintenance.
5-30 Oracle Real Application Clusters Administration and Deployment Guide
Service Deployment Options
Related Topics:
Distributed Transaction Processing in Oracle RAC
Adds services to a database and assigns them to instances.
Default Service Connections
Your Oracle RAC database includes an Oracle database service identified by
DB_UNIQUE_NAME
, if set, or
DB_NAME
or
PDB_NAME
, if not. This default service is always available on all instances in an Oracle RAC environment, unless an instance is in restricted mode. You cannot alter this service or its properties. Additionally, the database supports the following two internal services:
•
SYS$BACKGROUND
is used by the background processes only
•
SYS$USERS
is the default service for user sessions that are not associated with any application service
All of these services are used for internal management. You cannot stop or disable any of these internal services to do planned outages or to failover to Oracle Data Guard.
Do not use these services for client connections.
Note:
You can explicitly manage only the services that you create. If a feature of the database creates an internal service, you cannot manage it using the information in this chapter.
Restricted Service Registration
This feature allows listener registration only from local IP addresses, by default, and provides the ability to configure and dynamically update a set of IP addresses or subnets from which registration requests are allowed by the listener.
Security is a high priority to all enterprises, and network security and controlling access to the database is a critical component of overall security endeavours. Database
Instance registration with a listener succeeds only when the request originates from a valid node. The network administrator can specify a list of valid nodes, excluded nodes, or disable valid node checking. The list of valid nodes explicitly lists the nodes and subnets that can register with the database. The list of excluded nodes explicitly lists the nodes that cannot register with the database. The control of dynamic registration results in increased manageability and security of Oracle RAC deployments.
By default, valid node checking for registration (VNCR) is enabled. In the default configuration, registration requests are only allowed from nodes within the cluster, because they are redirected to the private subnet, and only nodes within the cluster can access the private subnet. Non-SCAN listeners only accept registration from instances on the local node. You must manually include remote nodes or nodes outside the subnet of the SCAN listener on the list of valid nodes by using the registration_invited_nodes_alias
parameter in the listener.ora
file or by modifying the SCAN listener using SRVCTL, as follows:
$ srvctl modify scan_listener -invitednodes node_list -invitedsubnets subnet_list
Workload Management with Dynamic Database Services 5-31
Administering Services
Related Topics:
Oracle Database Net Services Administrator's Guide
Administering Services
You can create and administer services with Oracle Enterprise Manager and the
SRVCTL utility. The following sections describe how to perform service-related tasks using these tools:
This section includes the following topics:
•
Overview of Service Administration
•
Administering Services with Oracle Enterprise Manager
•
Administering Services with SRVCTL
Note:
You can also use the DBMS_SERVICE package to create or modify services and service attributes, but SRVCTL will override any settings made using this package. The DBMS_SERVICE package is not recommended for use with services used by an Oracle RAC database, nor when Oracle Restart is used, nor when Oracle Clusterware is managing a single-instance database.
Overview of Service Administration
When you create and administer services, you are dividing the work that your database performs into manageable units.
The goal of using services is to achieve optimal utilization of your database infrastructure. You can create and deploy services based on business requirements.
Oracle Database can measure the performance for each service. Using the
DBMS_MONITOR
package, you can define both the application modules within a service and the individual actions for a module and monitor thresholds for these actions, enabling you to manage workloads to deliver capacity on demand.
When you create new services for your database, you should define the automatic
workload management characteristics for each service, as described in " Service
See Also:
Oracle Database Quality of Service Management User's Guide
if you are using
Oracle Database QoS Management with your Oracle cluster for details on how to configure the database services
In addition to creating services, you can:
•
Delete a service
. You can delete services that you created. However, you cannot delete or modify the properties of the default database service that Oracle
Database created.
5-32 Oracle Real Application Clusters Administration and Deployment Guide
Administering Services
•
Check the status of a service
. A service can be assigned different roles among the available instances. In a complex database with many services, you may not remember the details of every service. Therefore, you may have to check the status on an instance or service basis. For example, you may have to know the status of a service for a particular instance before you make modifications to that instance or to the Oracle home from which it runs.
•
Start or stop a service for a database or an instance
. A service must be started before it can be used for client connections to that instance. If you shut down your database, for example, by running the SRVCTL command srvctl stop database -db
db_unique_name
where
db_unique_name
is the name of the database you want to stop, then Oracle Database stops all services for that database. Depending on the service management policy, you may have to manually restart the services when you start the database. Both the srvctl stop database
and srvctl stop service
commands accept the
-force
option to forcibly disconnect connections. To drain sessions for planned outages do not use the
-force
option.
Note:
If Oracle Database QoS Management is enabled for the Oracle RAC database, then the services are automatically restarted after they are stopped.
•
Map a service to a consumer group
. You can map services to Resource Manager
Consumer groups to limit the amount of resources that services can use in an instance. You must create the consumer group and then map the service to the consumer group.
•
Enable or disable a service for a database or an instance
. By default, Oracle
Clusterware attempts to restart a service automatically after failures. You can prevent this behavior by disabling a service. Disabling a service is useful when you must perform database or instance maintenance, such as when you are performing an upgrade and you want to prevent connection requests from succeeding.
•
Relocate a service to a different instance
. You can move a service from one instance to another instance to re-balance workloads, for example, after adding or deleting cluster nodes.
Workload Management with Dynamic Database Services 5-33
Administering Services
Note:
• When you use services, do not set a value for the
SERVICE_NAMES parameter; Oracle Database controls the setting for this parameter for the services that you create and for the default database service. The service features that this chapter describes are not directly related to the features that Oracle Database provides when you set
SERVICE_NAMES
. In addition, setting a value for this parameter may override some benefits of using services.
• Service status information must be obtained from SRVCTL or from the service-related database views, such as dba_services
.
• If you specify a service using the
DISPATCHERS
initialization parameter, it overrides any service in the
SERVICE_NAMES
parameter, and cannot be managed. (For example, stopping the service with a SRVCTL command does not stop users connecting with the service.)
Related Topics:
Oracle Database Quality of Service Management User's Guide
Enabling Clients for Oracle RAC
Oracle Database PL/SQL Packages and Types Reference
Administering Services with Oracle Enterprise Manager
The Cluster Managed Database Services page is the master page for beginning all tasks related to services.
Access this page, as follows:
1.
In Oracle Enterprise Manager, go to the Cluster Database Home page.
See Also:
Oracle Database 2 Day DBA
for details on logging in to Oracle Enterprise
Manager.
2.
From the Availability menu, select Cluster Managed Database Services to display the Cluster Managed Database Services page.
3.
Enter or confirm the credentials for the Oracle RAC database and host operating system and click Continue to display the Cluster Managed Database Services page.
From the Cluster Managed Database Services page you can drill down to perform the following tasks:
• View a list of services for the cluster
• View the instances on which each service is currently running
• View the server pool and nodes offering the service in a policy-managed environment
5-34 Oracle Real Application Clusters Administration and Deployment Guide
Administering Services
• View the status for each service
• Create or edit a service
• Start or stop a service
• Enable or disable a service
• Perform instance-level tasks for a service
• Delete a service
Note:
You must have
SYSDBA
credentials to access a cluster database. Cluster
Managed Database Services does not permit you to connect as anything other than
SYSDBA
.
Related Topics:
Oracle Database 2 Day DBA
Oracle Database 2 Day + Real Application Clusters Guide
See Also:
• Oracle Enterprise Manager online help for more information about administering services with Oracle Enterprise Manager
•
Oracle Database 2 Day + Real Application Clusters Guide
for more information about using Oracle Enterprise Manager to manage services
Administering Services with SRVCTL
When you create a service using SRVCTL, you must start the service with a separate
SRVCTL command.
However, you may later have to manually stop or restart the service. You may also have to disable the service to prevent automatic restarts, to manually relocate the service, or obtain status information about the service. The following sections explain how to use SRVCTL to perform the following administrative tasks:
•
•
Creating Services for Application Continuity and Transaction Guard
•
Starting and Stopping Services with SRVCTL
•
Enabling and Disabling Services with SRVCTL
•
Relocating Services with SRVCTL
•
Obtaining the Status of Services with SRVCTL
•
Obtaining the Configuration of Services with SRVCTL
Workload Management with Dynamic Database Services 5-35
Administering Services
Creating Services with SRVCTL
To create a service with SRVCTL, use the srvctl add service
command on the command line.
Related Topics:
Adds services to a database and assigns them to instances.
Creating Services for Application Continuity and Transaction Guard
To configure services for Application Continuity, when you create a service using
SRVCTL, set the
-failovertype
parameter to
TRANSACTION
and
commit_outcome
to
TRUE
.
When using Application Continuity and Transaction Guard with your applications, you must configure a service. This section describes how to configure these application services depending on the functionality you plan to implement.
Creating Services for Application Continuity
Additionally, you can set values for these other service parameters for Application
Continuity and load balancing:
•
-replay_init_time
: Specifies how long, in seconds, you allow replay to start.
Oracle recommends that you choose a value based on how long you will allow replay to be initiated. The default value is 300 seconds.
•
-retention
: Specifies the time (in seconds) that the commit outcome information is stored in the database. The default value is 86400 (1 day).
•
-session_state
: After a COMMIT has executed, if the state was changed in that transaction, then it is not possible to replay the transaction to reestablish that state if the session is lost. When configuring Application Continuity, the applications are categorized depending on whether the session state after the initial setup is dynamic or static, and then whether it is correct to continue past a
COMMIT operation within a request.
–
Dynamic
: (default) A session has a dynamic state if the session state changes are not fully encapsulated by the initialization, and cannot be fully captured in a callback at failover. Once the first transaction in a request commits, failover is internally disabled until the next request begins. This is the default mode that almost all applications should use for requests.
–
Static
: (special—on request) A session has a static state if all session state changes, such as NLS settings and PL/SQL package state, can be repeated in an initialization callback. This setting is used only for database diagnostic applications that do not change session state. Do not specify
STATIC
if there are any non-transactional state changes in the request that cannot be reestablished by a callback. If you are unsure what state to specify, use
DYNAMIC
.
•
-failoverretry
: Number of connection retries for each connection attempt; recommended value is 30.
•
-failoverdelay
: Delay in seconds between each connection attempt; recommended value is 10.
5-36 Oracle Real Application Clusters Administration and Deployment Guide
Administering Services
•
-notification
: FAN is highly recommended—set this value to
TRUE
to enable
FAN for OCI and ODP.Net clients.
•
-clbgoal
: For connection load balancing, use
SHORT
when using run-time load balancing.
•
-rlbgoal
: For run-time load balancing, set to
SERVICE_TIME
.
To create a service for Application Continuity for a policy-managed Oracle RAC database, use a command similar to the following, where racdb
is the name of your
Oracle RAC database, app2
is the name of the service you are modifying, and
Svrpool1
is the name of the server pool in which the service is offered:
$ srvctl add service -db racdb -service app2 -serverpool Srvpool1
-failovertype TRANSACTION -commit_outcome TRUE -replay_init_time 1800
-retention 86400 -notification TRUE -rlbgoal SERVICE_TIME -clbgoal SHORT
-failoverretry 30 -failoverdelay 10
You can use SRVCTL to modify an existing service for Application Continuity, similar to the following command, where racdb
is the name of your Oracle RAC database, and app1
is the name of the service you are modifying:
$ srvctl modify service -db racdb -service app1 -clbgoal SHORT
-rlbgoal SERVICE_TIME -failoverretry 30 -failoverdelay 10
-failovertype TRANSACTION -commit_outcome TRUE -replay_init_time 1800
-retention 86400 -notification TRUE
Creating Services for Transaction Guard
To enable Transaction Guard, but not Application Continuity, create the service using
SRVCTL and set only
-commit_outcome TRUE
.
You can use SRVCTL to modify an existing service to enable Transaction Guard, similar to the following command, where racdb
is the name of your Oracle RAC database, and app2
is the name of the service you are modifying:
$ srvctl modify service -db racdb -service app2 -commit_outcome TRUE
-retention 86400 -notification TRUE
In the preceding example, the
-retention
parameter specifies how long, in seconds, to maintain the history. Additionally the
–notification
parameter is set to
TRUE
, enabling FAN events.
To use Transaction Guard, a DBA must grant permission, as follows:
GRANT EXECUTE ON DBMS_APP_CONT;
Related Topics:
Oracle Database Development Guide
Starting and Stopping Services with SRVCTL
For applications to connect using a server, the service must be started. If you stop a service, then it is temporarily unavailable, but is still subject to automatic restart and failover.
Enter the following SRVCTL syntax at the command line to start or stop a service:
$ srvctl start service -db db_unique_name [-service
service_name_list
]
[-instance
inst_name
] [-startoption
start_options
]
Workload Management with Dynamic Database Services 5-37
Administering Services
$ srvctl stop service -db db_unique_name -service
service_name_list
[-instance
inst_name
] [-startoption
start_options
]
Enabling and Disabling Services with SRVCTL
If you disable a service, then Oracle Clusterware does not consider the service for automatic startup, failover, or restart. You might disable a service when performing application maintenance, to ensure the service is not accidentally restarted by Oracle
Clusterware until your maintenance operations are complete. To make the service available for normal operation again, you enable the service.
Use the following SRVCTL syntax from the command line to enable and disable services:
$ srvctl enable service -db
db_unique_name
-service
service_name_list
[-instance
inst_name
]
$ srvctl disable service -db
db_unique_name
-service
service_name_list
[-instance
inst_name
]
Relocating Services with SRVCTL
Run the srvctl relocate service
command from the command line to relocate a service. You might use this command when a service has failed over to an available instance, but you want to move it back to the preferred instance after that instance is restarted.
The following command relocates the crm
service from instance apps1
to instance apps3
:
$ srvctl relocate service -db apps -service crm -oldinst apps1 -newinst apps3
The following command relocates the crm
service from node1
to node3
using node syntax:
$ srvctl relocate service -db apps -service crm -currentnode node1
-targetnode node3
Obtaining the Status of Services with SRVCTL
Run the srvctl status service
command from the command line to obtain the status of a service. For example, the following command returns the status of the services that are running on the apps
database:
$ srvctl status service -db apps
Service erp is running on nodes: apps02,apps03
Service hr is running on nodes: apps02,apps03
Service sales is running on nodes: apps01,apps04
Obtaining the Configuration of Services with SRVCTL
Run the srvctl config service
command from the command line to obtain the high availability configuration of a service. For example, the following command returns the configuration of the erp
service that is running on the apps
database:
$ srvctl config service -db apps -service erp
Service name: erp
Service is enabled
Server pool: pool1
5-38 Oracle Real Application Clusters Administration and Deployment Guide
Global Services
Cardinality: 1
Disconnect: false
Service role: PRIMARY
Management policy: AUTOMATIC
DTP transaction: false
AQ HA notifications: true
Global: false
Commit Outcome: true
Failover type: TRANSACTION
Failover method: NONE
TAF failover retries: 30
TAF failover delay: 10
Connection Load Balancing Goal: LONG
Runtime Load Balancing Goal: SERVICE_TIME
TAF policy specification: NONE
Edition:
Pluggable database name:
Maximum lag time: ANY
SQL Translation Profile:
Retention: 86400 seconds
Replay Initiation Time: 1800 seconds
Session State Consistency: STATIC
Preferred instances: apps
Available instances:
Global Services
Oracle RAC supports database services and enables service-level workload management across instances in a single cluster.
Global services provide dynamic load balancing, failover, and centralized service management for a set of replicated databases that offer common services. The set of databases may include Oracle RAC and non-clustered Oracle databases interconnected by Oracle Data Guard, Oracle GoldenGate, or any other replication technology.
When you create and use global services, the following workload management features are available:
• Ability to specify preferred and available databases for a global service
• Handling of replication lag
• Geographical affinity between clients and servers
• Connection load balancing
• Run-time load balancing
• Inter-database service failover
• Fast connection failover
• Connect-time failover
• Application Continuity
• Transaction Guard
• Backward compatibility with existing clients
Workload Management with Dynamic Database Services 5-39
Service-Oriented Buffer Cache Access
Note:
You can manage instance placement of a global service within an Oracle RAC database with SRVCTL but you can only manage other global service attributes with GDSCTL.
Related Topics:
Oracle Database Global Data Services Concepts and Administration Guide
Service-Oriented Buffer Cache Access
Service-oriented buffer cache access improves performance by managing data with the service to which the data belongs.
Access of an object, over time, through a service is mapped and persisted to the database, and this information can be used to improve performance. Blocks that are accessed through the service are cached in the instances where the services are running and, more importantly, the information is not cached where the services are not running.
This information can also be used to pre-warm the cache prior to a service starting.
The service start-up can be triggered either by instance start-up or by service relocation. Service-oriented buffer cache access provides consistent performance to any user of that service because the blocks that the service user accesses are cached in the new relocated instance.
Connecting to a Service: An Example
The following example illustrates how to create a service and then gives several examples of connecting to that service using different client methods.
In this example the service is enabled for run-time load balancing, as follows:
• Service Name:
HR.example.com
– Running on database named CRM
– The system consists of 4 nodes
• Specifying
SERVICE_TIME
as the value for the
-rlbgoal
parameter
• SCAN address of the listener is rws3010104-scan.example.com
• Listener port is 1585
The service has a cardinality of two, but if needed, can be offered by any of the CRM database instances. The service configuration is as follows:
• Preferred Instances: CRM1, CRM2
• Available Instances: CRM3, CRM4
• Specifying
SHORT
as the value for the
-clbgoal
parameter
The application using this service takes advantage of Application Continuity, so you must set
-failovertype
and
-commit_outcome
. Use the default retention parameters, but set a 10 second delay between connection attempts, and up to 40 retries before failing to get a connection.
5-40 Oracle Real Application Clusters Administration and Deployment Guide
Connecting to a Service: An Example
Creating the HR Service Using SRVCTL
Create the HR service using SRVCTL, as follows:
$ srvctl add service –db CRM –service HR.example.com –preferred CRM1,CRM2
–available CRM3,CRM4 –clbgoal SHORT –failovertype TRANSACTION
–commit_outcome TRUE –failoverdelay 10 –failoverretry 40
Start the
HR.example.com
service, as follows:
$ srvctl start service –db CRM –service HR.example.com
The service is now be available on up to two instances, and CRM1 and CRM2 are the preferred instances.
Connecting to the HR Service from a JDBC Application
The application that connects to the HR service, in this example, is a JDBC application using the JDBC Universal Connection Pool with the JDBC thin driver.
In this example, a URL is constructed specifying the thin-style service name format for the database specifier. Fast Connection Failover is enabled, and remote Oracle
Notification Service is configured, where the Oracle Notification Service daemon on the cluster listens on port 6200.
//import packages and register the driver import java.sql.Connection; import java.sql.SQLException; import java.sql.Statement; import oracle.ucp.jdbc.PoolDataSourceFactory; import oracle.ucp.jdbc.PoolDataSource;
PoolDataSource pds = PoolDataSourceFactory.getPoolDataSource();
//set the connection properties on the data source.
pds.setConnectionPoolName("FCFPool"); pds.setFastConnectionFailoverEnabled(true); pds.setONSConfiguration("nodes=rws3010104-scan.example.com:6200"); pds.setConnectionFactoryClassName("oracle.jdbc.pool.OracleDataSource"); pds.setURL("jdbc:oracle:thin:@//rws3010104-scan.example.com:1585/HR.example.com"); pds.setUser("HR"); pds.setPassword("hr");
//Override any pool properties.
pds.setInitialPoolSize(5);
//Get a database connection from the datasource.
Connection conn = pds.getConnection();
// do some work
//return connection to pool conn.close(); conn=null
Related Topics:
Oracle Universal Connection Pool Developer’s Guide
Workload Management with Dynamic Database Services 5-41
Connecting to a Service: An Example
5-42 Administration and Deployment Guide
6
Ensuring Application Continuity
Application Continuity
is a feature that enables the replay, in a non-disruptive and rapid manner, of a request against the database after a recoverable error that makes the database session unavailable so an outage appears to the user as no more than a delayed execution of the request.
The request can contain transactional and non-transactional work. After a successful replay, the application can continue where that database session left off, instead of having users left in doubt, not knowing what happened to their funds transfers, flight bookings, and so on, and avoiding the need to reboot mid-tier servers to recover from an overload of log ins when the application comes back online. With Application
Continuity, the end-user experience is improved by masking many outages, planned and unplanned, without the application developer needing to attempt to recover the request.
Without Application Continuity, it can be almost impossible for an application to mask outages in a safe way, for reasons that include the following:
• The state at the client remains at present time, with entered data, returned data, and variables cached.
• If a
COMMIT
has been issued, then the
COMMIT
failure message cannot be retrieved if it is not received by the client or the application.
• Checking the status of an in-doubt tansaction at a point in time is no guarantee that it will not
COMMIT
later.
• Non-transactional database session state that the application needs to operate is lost.
• If the request can continue, the database and the database session must be in the right state.
With Application Continuity, however, Oracle Database, the Oracle drivers, and the
Oracle connection pools all collaborate to mask many outages in a safe and reliable way.
Application Continuity improves developer productivity by attempting to mask outages that can be masked. However, applications still must include error handling for these cases:
•
Nonrecoverable
errors, such as invalid input data. (Application Continuity applies only to recoverable errors.)
• Recoverable errors when replay has encountered a restriction, such as use of concrete classes in the application, or when replay has not been able to restore the client-visible state to that on which the client may have made decisions so far.
Ensuring Application Continuity 6-1
Fast Application Notification
Introduced in Oracle Database 12c Release 1 (12.1.0.1), Application Continuity strengthens the fault tolerance of systems and applications that use an Oracle database.
This chapter assumes that you are familiar with the major relevant concepts and techniques of the technology or product environment in which you are using
Application Continuity, such as Oracle WebLogic Server, Oracle RAC, or Oracle
Active Data Guard (Oracle ADG).
This chapter includes the following topics:
•
•
Application Continuity Operation and Usage
•
Potential Side Effects of Application Continuity
•
Restrictions and Other Considerations for Application Continuity
•
•
Transaction Guard for Improving Client Failover
•
Failing Over OCI Clients with TAF
Fast Application Notification
The Oracle RAC high availability framework monitors a database and its services and sends event notifications using Fast Application Notification (FAN).
Oracle Database focuses on maintaining the highest possible service availability. In
Oracle RAC, services are designed to be continuously available with loads shared across one or more instances. The Oracle RAC high-availability framework maintains service availability by using Oracle Clusterware and resource profiles. Oracle
Clusterware recovers and balances services according to business rules and the service attributes.
This includes the following topics:
•
Overview of Fast Application Notification
•
•
•
Fast Application Notification High Availability Events
•
Subscription to High Availability Events
•
Using Fast Application Notification Callouts
Related Topics:
Enabling Clients for Oracle RAC
Overview of Fast Application Notification
FAN provides immediate interrupt of clients following outages related to the database, nodes, and networks.
6-2 Oracle Real Application Clusters Administration and Deployment Guide
Fast Application Notification
FAN is essential to break clients out of TCP/IP timeouts immediately following failures. FAN notifies clients immediately when resources become available and initiates draining of database sessions so clients experience no outages during planned maintenance. FAN also includes notifying configuration- and service-level information that includes changes in service status.
The Oracle client drivers and Oracle connection pools respond to FAN events and take immediate action. FAN UP and DOWN events apply to services, databases, instances, networks, and nodes.
Note:
FAN is supported from Oracle Database 10g release 2 (10.2), on.
Oracle connection pools, for example, use FAN to receive very fast notification of failures, to balance connections following failures, and to balance connections again after the failed components are repaired. So, when a service at an instance starts, the connection pool uses the FAN event to route work to that resource, immediately.
When a service at an instance or node fails, the connection pool uses the FAN event to immediately interrupt applications to recover. FAN is essential to prevent applications from hanging on TCP/IP timeouts.
Importance of FAN
Applications can waste time in many critical ways:
• Waiting for TCP/IP timeouts when a node fails without closing sockets, and for every subsequent connection while that IP address is down.
• Attempting to connect when services are down.
• Not connecting when services resume.
• Processing the last result at the client when the server goes down.
• Attempting to execute work on sub-optimal nodes.
When a node fails without closing sockets, all sessions that are blocked in an I/O wait
(read or write) wait for tcp_keepalive
. This wait status is the typical condition for an application connected by a socket. Sessions processing the last result are even worse off, not receiving an interrupt until the next data is requested. Using FAN events eliminates applications waiting on TCP timeouts, time wasted processing the last result at the client after a failure has occurred, and time wasted executing work on slow, hung, or dead nodes.
For cluster configuration changes, the Oracle RAC high availability framework publishes a FAN event immediately when a state change occurs in the cluster. Instead of waiting for the application to time out against the database and detect a problem, applications can receive FAN events and react immediately. With FAN, in-flight transactions are immediately terminated and the client notified when the instance fails.
FAN also publishes load balancing advisory events. Applications can take advantage of the load balancing advisory FAN events to direct work requests to the instance in the cluster that is currently providing the best service quality.
Oracle Database 12c release 2 (12.2) client drivers are FAN-aware, and FAN is enabled, by default. This includes the JDBC Thin driver (12.2.0.1) and Oracle Data Provider for
Net (ODP.NET) drivers. A client driver can detect planned and unplanned FAN events and take action beneath the application.
Ensuring Application Continuity 6-3
Fast Application Notification
For planned maintenance and applications using OCI or Pro* (and not using the OCI session pool or Tuxedo), an application must check
OCI_ATTR_SERVER_STATUS
.
Add this check when sessions are returned to your own connection pool, and for idle connections, regularly.
Following a FAN down event with planned maintenance, this attribute is set to
OCI_SERVER_NOT_CONNECTED
. The application closes the connection after reading this disconnected status. The session remains open for draining of active work until the application closes, providing error-free failover.
You can take advantage of FAN events in the following ways:
• Applications can use FAN without programmatic changes if you use an integrated Oracle client. The integrated clients for FAN events include Oracle
JDBC Universal Connection Pool, ODP.NET connection pool, OCI session pool,
Oracle WebLogic Server Active Gridlink for Oracle RAC, and OCI and ODP.NET
clients. The integrated Oracle clients must be Oracle Database 10g release 2 (10.2) or later to take advantage of the FAN high-availability events. The pooled clients can also take advantage of the load balancing advisory FAN events.
• You can configure third-party application containers, such as those provided by
Apache Tomcat and WebSphere, to use the built-in FAN support offered by using the Universal Connection Pool in place of the default pool, which is certified as a connection pool for third-party Java application servers including Apache Tomcat and WebSphere.
• Use the FAN-aware capability of the Oracle drivers by using standard interfaces to test connections on get or release from the third-party connection pools in use by third-party application servers or custom applications.
– This solution applies to standard Java applications through the use of the standard TNS connect string and ensures that the ons.jar
and simpleFAN.jar
files are available on the application CLASSPATH.
– For the OCI/OCCI driver, the OCI_ATTR_SERVER_STATUS server context handle attribute is sensitive to FAN events and will return
OCI_SERVER_NOT_CONNECTED
if the connection has been affected by a FAN event.
• You can implement FAN with server-side callouts on your database tier.
• Applications can use FAN programmatically by using the JDBC and Oracle RAC
FAN application programming interface (API) or by using callbacks with OCI and
ODP.NET to subscribe to FAN events and to run event handling actions upon the receipt of an event.
If you use one of the integrated clients listed in the first item of the preceding list, then, for DOWN events, the disruption to the application is minimized because the FANaware client terminates the connections to the failed instance or node before they are reused. Active work can be allowed to complete and, if there is a surviving instance, then continuous service can be maintained for ongoing work. Any sessions active when the instance or service stops are terminated and the application user is immediately notified. Incomplete transactions can be protected by Application
Continuity, if it is enabled. Application users who request connections are directed to available instances, only.
For
UP
events, when services and instances are started, new connections are created so that the application can immediately take advantage of the extra hardware resources or additional capacity.
6-4 Oracle Real Application Clusters Administration and Deployment Guide
Fast Application Notification
To take advantage of FAN-aware capabilities in the drivers, as mentioned in the previous list, the following is required:
• For the thin Java driver, beginning with release 12.2, FAN is automatically enabled by placing the ons.jar
and simpleFAN.jar
files on the CLASSPATH, and by using the recommended TNS format (as shown in
recommended TNS format automatically configures ONS. Also with the Java thin driver, FAN is supported for both planned and unplanned events. For unplanned outages, the FAN interrupt is immediate. For planned maintenance, configure the
Java application servers or custom pools using standard interfaces to test connections on get or release from third-party connection pools. For example,
TestConnectionsOnReserve
,
TestOnBorrow
, or
PreTest
connections, depending on the application server.
With this approach, when a FAN event is received during planned maintenance,
Fast Connection Failover closes sessions when they are tested, because the application does not have a connection to the database at this time, and can retry for a new connection. The connection tests may use isValid
, isClosed
, isUsable
,
PingDatabase
, or a SQL statement that is preceded by the hint
/*+
CLIENT_CONNECTION_VALIDATION */
.
• For a SQL test, the SQL syntax must begin with the hint
/*+
CLIENT_CONNECTION_VALIDATION */
. At the time the SQL command runs, the driver will drain the connection, if it is affected by the upcoming planned maintenance. Connection pools, data sources, and, in the programmatic case, customer applications, must all be ready to manage the recoverable error that occurs when the SQL command runs, which usually closes the physical connection.
Note:
The SQL hint must be placed as the first non-comment token within the
SQL string to avoid changing current, driver-based SQL parsing. For example:
/*+ CLIENT_CONNECTION_VALIDATION */ SELECT 1 FROM DUAL;
• Third-party Java application servers and Java applications can use the
PooledConnection
standard interface when developing connection pools.
• Beginning with the 11.2.0.3 release of the OCI/OCCI driver, when the
OCI_ATTR_SERVER_STATUS server context handle attribute returns
OCI_SERVER_NOT_CONNECTED
, the application must terminate the connection.
Work will be drained for planned maintenance. The 12.2 release of the driver can also detect
OCISessionRelease
and
OCIRequestEnd
when it receives a planned DOWN event.
The following table describes the standard tests available for several of the more common application servers:
Ensuring Application Continuity 6-5
Fast Application Notification
Table 6-1 Standard Tests for Some Common Application Servers
Application Server Connection Test to Database
Oracle WebLogic Server The tests offered include:
•
TestConnectionsonReserve
: isUsable
, isValid
, or
PingDatabase
•
TestConnectionsOnCreate
(SQL syntax):
/*+ CLIENT_CONNECTION_VALIDATION */ Select 1 from dual;
Oracle WebLogic Server
Active Gridlink
The test is embedded: isUsable
IBM WebSphere
RedHat JBoss
Apache Tomcat
PreTest
connections (SQL syntax):
/*+ CLIENT_CONNECTION_VALIDATION */ Select user from dual; check-valid-connection-sql
(SQL syntax):
Select 1 from dual;
There are two tests available— testOnBorrow
and testOnReturn
—and they both use SQL syntax to test the connection to the database:
/*+ CLIENT_CONNECTION_VALIDATION */ Select 1 from dual;
Oracle recommends that you use the following format for supporting automatic configuration of FAN:
Example 6-1 Automatic Configuration of FAN
alias =(DESCRIPTION =
(CONNECT_TIMEOUT=90)(RETRY_COUNT=20)(RETRY_DELAY=3)(TRANSPORT_CONNECT_TIMEOUT=3)
(ADDRESS_LIST =
(LOAD_BALANCE=on)
( ADDRESS = (PROTOCOL = TCP)(HOST=primary-scan)(PORT=1521)))
(ADDRESS_LIST =
(LOAD_BALANCE=on)
( ADDRESS = (PROTOCOL = TCP)(HOST=secondary-scan)(PORT=1521)))
(CONNECT_DATA=(SERVICE_NAME = gold-cloud)))
FAN callouts are server-side scripts or executables that run whenever a FAN event is generated. You can design and build callouts to do many things. For example:
• Log status information
• Page DBAs or to open support tickets when resources fail to start
• Automatically start dependent external applications that must be co-located with a service
• Change resource plans or shut down services when the number of available instances for a policy-managed database decreases, for example, if nodes fail
6-6 Oracle Real Application Clusters Administration and Deployment Guide
Fast Application Notification
• Automate the fail back of a service to preferred instances for administratormanaged databases, if needed
FAN events are published using Oracle Notification Service and Oracle Streams
Advanced Queuing, the latter being continued for backward compatibility to previous
Oracle Database releases. The publication mechanisms are automatically configured as part of your Oracle RAC installation. If you are using thin Java JDBC connections, then the client can be automatically configured for Oracle Notification Service, by obtaining the database-server Oracle Notification Service configuration from the database connection. It is not necessary to configure Oracle Notification Service on the client.
Oracle Net Services listeners and Global Data Services (GDS) are integrated with FAN events, enabling the listener and GDS to immediately de-register services provided by the failed instance and to avoid erroneously sending connection requests to failed instances.
If you specify the connection load balancing goal
CLB_GOAL_SHORT
for the service, then the listener uses the load balancing advisory when the listener balances the connection loads. When load balancing advisory is enabled, the metrics used for the listener are finer grained.
Managing Unplanned Outages
You can assign services to one or more instances in an administrator-managed Oracle
RAC database or to server pools in a policy-managed database.
If Oracle RAC detects an outage, then Oracle Clusterware isolates the failed component and recovers the dependent components. For services, if the failed component is an instance, then Oracle Clusterware attempts to maintain the cardinality of the service. If the service definition allows for failover and that is necessary to maintain cardinality, then failover occurs.
FAN events can occur at various levels within the Oracle Database architecture and are published through Oracle Notification Service and Oracle Streams Advanced
Queuing for backward compatibility with previous OCI clients. FAN callouts can also be written to execute on the database server in response to FAN events.
Note:
Oracle Database does not run Oracle RAC callouts with guaranteed ordering.
Callouts are run asynchronously and they are subject to scheduling variability.
FAN is published from a surviving node when the failed node is out of service. The location and number of instances in an Oracle RAC environment that provide a service are transparent to applications. Restart and recovery are automatic, including the restarting of the subsystems, such as the listener and the Oracle Automatic Storage
Management (Oracle ASM) processes, not just the database. You can use FAN callouts to report faults to your fault management system and to initiate repair jobs.
It is a complex task for application developers to mask outages of a database session
(instance, node, storage or network, or any other related component) and, as a result, errors and timeouts are often exposed to the end users leading to user frustration, lost productivity, and lost opportunities. Together, FAN and Application Continuity mask outages from users and applications by recovering the in-flight work for impacted database sessions following outages. Application Continuity performs this recovery beneath the application so that the outage appears to the application as a slightly delayed execution of the request.
Ensuring Application Continuity 6-7
Fast Application Notification
Related Topics:
Application Continuity masks many recoverable database outages
(when replay is successful) from applications and users by restoring the database session: the full session, including all states, cursors, variables, and the last transaction if there is one.
Oracle Database Net Services Administrator's Guide
Managing Planned Maintenance
For repairs, upgrades, and changes that require you to isolate one or more instances or nodes, Oracle RAC provides interfaces that relocate, disable, and enable services to minimize service disruption to application users.
When you relocate a service, you indicate the service should run on another instance temporarily. If you forcibly disable a service, then the service is stopped on all database instances and is no longer available. Disabled services are not restarted automatically. When a service is stopped or relocated, FAN is published with a planned reason code, typically reason=user
. Once you complete the operation, you can return the service to normal operation or enable the service and then restart it.
When a service restarts, FAN is published with
UP
status codes.
Due to dependencies, if you manually shut down your database, then all of your services for that database automatically stop. If you want your services to automatically start when you manually restart the database, then you must set the management policy of the service to automatic. If you want to shut down only one instance of the database and you want the service to remain offered, then you can either relocate the service using srvctl relocate service
or stop the instance using srvctl stop instance
, which enables the service to automatically failover according to its failover policy.
In either case, Oracle recommends that work running under the service drain at request boundaries. The drain interval is specified as an attribute of the service or you can provide a drain interval on the SRVCTL command line.
This section includes the following topics:
•
Managing Planned Maintenance Without User Interruption
•
Managing a Group of Services for Maintenance
Related Topics:
When you use Oracle Clusterware to manage your database, you can configure startup options for each individual database service when you add the service using the srvctl add service
command with the
policy
parameter.
Managing Planned Maintenance Without User Interruption
You may have to stop database instances for maintenance, such as upgrading the
Oracle software, patching, and replacing hardware.
The steps in this section result in the least impact to users and requests are not interrupted.
6-8 Oracle Real Application Clusters Administration and Deployment Guide
Fast Application Notification
For planned maintenance, Oracle recommends that you drain requests over a controlled time period from FAN-enabled Oracle connection pools. The service attributes
-drain_timeout
and
-stopoption
control the drain time period, and then how the service manages sessions that have not completed once this time period expires. Requests that complete and then check back in to the pool or close, can be directed to a new location that is not affected by the planned maintenance.
When using the Oracle Universal Connection Pool, sessions gradually drain, according to the value of the -drain_timeout parameter, so there is minimal impact to other work at the target instances. This also prevents overwhelming numbers of logins when the service becomes available again.
Application Continuity provides additional cover, giving continuous service for those requests that do not complete within the allotted drain time.
Using any FAN-aware pool with Fast Connection Failover configured (such as OCI session pools, Oracle Universal Connection Pool, Oracle WebLogic Server Active
GridLink for Oracle RAC, or ODP.NET) allows sessions to drain at
boundaries after receipt of the FAN planned
DOWN
event.
Requests are far more important than transactions because they enable the issued work to complete. For draining requests, the Oracle Universal Connection Pool uses the drain timeout to gradually drain, which prevents an overload of logins on the instances drained, by slowly releasing the original sessions across the time period rather than all at once. Gradual draining has the benefit of not disturbing the other work ongoing at the target instances.
Both
DRAIN_TIMEOUT
and
STOP_OPTION
are service attributes that you can define when you add the service or modify it after creation. You can also specify these attributes using SRVCTL, which will take precedence over what is defined on the service. You can specify the
-drain_timeout
and
-stopoption
parameters when using the following SRVCTL commands:
• srvctl add service
• srvctl modify service
• srvctl relocate service
• srvctl stop service
• srvctl stop database
• srvctl stop instance
To manage planned maintenance without user interruption:
1.
Use SRVCTL to relocate the service from an instance or, if you are using a uniform or all-preferred service, then shut down the service on an instance. Use the
-force flag with the previously listed SRVCTL commands. You must use the
-force
flag if you specify the
-stopoption
parameter on the command line when you run either srvctl relocate service
or srvctl stop service
. For example:
$ srvctl relocate service –database mycdb01 –service myservice –drain_timeout 120
–stopoption IMMEDIATE –oldinst mycdb01_01 -force
The preceding command relocates the service named myservice01
from the instance named mycdb01_01
to any instance on which it is configured to run.
Oracle Clusterware chooses this instance if you do not specify a target on the command line, and waits two minutes (in this example) for any active sessions to
Ensuring Application Continuity 6-9
Fast Application Notification drain, after which any sessions remaining on mycdb01_01
are forcibly disconnected. The connection pool automatically releases a connection at a request boundary.
2.
The FAN planned
DOWN
event clears idle sessions from the connection pool immediately and marks active sessions to be released at the next check-in. These
FAN actions drain the sessions from the instance without disrupting the users.
Existing connections on other instances remain usable, and new connections can be opened to these instances if needed.
3.
Not all sessions, in all cases, will check their connections into the pool. Oracle recommends, as a best practice, to have a timeout period (by setting the
drain_timeout
parameter), after which the instance is forcibly shut down or the service stopped, evicting any remaining client connections.
After the drain interval expires, the
-stopoption
parameter is implemented, which you can define against a service or a database, as follows:
• For a service, you can specify the following stop options: NONE,
TRANSACTIONAL, and IMMEDIATE
• For a database, you can specify the following stop options: NORMAL,
TRANSACTIONAL, TRANSACTIONAL LOCAL, IMMEDIATE, and ABORT
The database stop options correlate to the service stop options, as follows:
NORMAL=NONE
TRANSACTIONAL/TRANSACTIONAL LOCAL=TRANSACTIONAL
IMMEDIATE/ABORT=IMMEDIATE
For those services that are configured to use Application Continuity, an attempt is made to recover these remaining sessions, after they are terminated, masking the outage from users and applications.
If you do not want Application Continuity to attempt to replay sessions, then specify the
-noreplay
flag on the SRVCTL command line.
4.
Once maintenance is complete, restart the instance and the service on the original node.
5.
The FAN
UP
event for the service informs the connection pool that a new instance is available for use, allowing sessions to be created on this instance at next request boundaries.
Related Topics:
Application Continuity masks many recoverable database outages
(when replay is successful) from applications and users by restoring the database session: the full session, including all states, cursors, variables, and the last transaction if there is one.
Managing a Group of Services for Maintenance
Many enterprises run a large number of services, whether it be many services offered by a single database or instance, or many databases offering a few services running on the same node.
6-10 Oracle Real Application Clusters Administration and Deployment Guide
Fast Application Notification
You no longer need to run SRVCTL commands for each individual service but need only specify the node name, database name, pluggable database name, or the instance name for all affected services.
• For example, if you want to stop all of the services running on a given node, then you could use the following command:
$ srvctl stop service –node racnode01 –drain_timeout 60 –stopoption IMMEDIATE
The command stops all services running on racnode01
, allowing a drain interval of 60 seconds. After 60 seconds any remaining sessions are stopped immediately.
The 60-second drain timeout interval overrides any attribute setting on any of the services.
The command could also be qualified to stop the databases on a node, as in the following example:
$ srvctl stop database -node racnode01 -drain_timeout 60 –stopoption
TRANSACTIONAL
-failover –force
When you specify the
-failover
parameter:
– All services are relocated, if possible, respecting the drain timeout interval and the stop option specified.
– Any services that cannot be failed over are stopped, using the stop option specified.
– Wait for the length of the drain timeout interval or until all sessions for targeted services are removed, whichever is sooner.
– All instances stop according to the stop option specified.
When you specify the
–stopoption
parameter:
– Remaining services stop according to the drain timeout interval and stop option specified.
– Wait for the length of the drain timeout interval or until all sessions for targeted services are removed, whichever is sooner.
– The instance stops using the
TRANSACTIONAL
stop option.
This section includes the following topics:
•
•
Pluggable Database-Level Operations
•
•
Starting Services
You can use the srvctl start service
command to start all services on a node, all services offered by a database, all services offered by a pluggable database, or all services offered on an instance or within a given server pool.
Ensuring Application Continuity 6-11
Fast Application Notification
You can also supply a list of services (a subset of all services) to the srvctl start service
command that you want to start. Additionally, you can provide a node restriction, used in conjunction with the database option, for all services that can be started on a particular node. You can restrict the srvctl start service
command to start only the parallel query service by specifying the
-pq
parameter.
The following examples illustrate how you can start services:
• To start all of the services offered by a single pluggable database:
$ srvctl start service –db myRACCDB01 –pdb myPDB01 –startoption OPEN
To start all services on a given database and any of its pluggable databases:
$ srvctl start service –db myRACDB
To start only a subset of the services offered by a pluggable database:
$ srvctl start service –db myRACDB –pdb myPDB01 –service
"myFirstService,mySecondService,myThirdService"
To start a list of services on a given database, regardless of any pluggable database with which they are associated:
$ srvctl start service –db myRACDB –service
"myFirstService,mySecondService,myThirdService"
To start all services for a database that can run on a given node:
$ srvctl start service –d myRACDB –node racnode01
Pluggable Database-Level Operations
You can use SRVCTL to manage services on pluggable databases.
• To start all services for a pluggable database, for all instances or a single instance:
$ srvctl start service -db db_name -pdb pdb_name [-instance instance_name] [service service_name]
• To stop all services for a pluggable database, for all instances or a single instance:
$ srvctl stop service -db db_name -pdb pdb_name [-instance instance_name] [service service_name] -drain_timeout
[-force [-stopoption]] [-noreplay]
Note:
The
-pdb pdb_name
parameter is optional. If you omit the pluggable database name, then the operation occurs for the entire container database (all pluggable databases within this container).
Relocating Services
You can use the srvctl relocate service
command to relocate services to a target destination, which can be an instance, a node, a database, or a pluggable database.
• In the following command examples, all services are relocated from the named database, pluggable database, instance, or node. The services will only relocate if the target can support that service, as defined by the service configuration. Any services that cannot be relocated remain at the original location. A placement error
6-12 Oracle Real Application Clusters Administration and Deployment Guide
Fast Application Notification is recorded against any services that could not be relocated, or were already running at the new target. Services that fail to relocate remain running at their original location, and any sessions remain active.
$ srvctl relocate service –database myRACCDB –oldinst RACCDB_01 –newinst
RACCDB_03
-drain_timeout 30 -force or
$ srvctl relocate service –database myRACCDB –pdb myPDB01 –currentnode racnode01
–targetnode racnode02 -drain_timeout 30 -force –noreplay
The relocate operation starts the service in the new location prior to stopping the service in its existing location.
• If you do not specify a target destination, then Oracle Clusterware relocates all services or specific services from the specified database, pluggable database, instance, or node, as in the following examples:
$ srvctl relocate service –database myRACCDB –service "myService01,myService02"
-drain_timeout 30 -force or
$ srvctl relocate service –database myRACCDB –pdb myPDB01 -drain_timeout 30
-force –noreplay
If there is no valid target available, then the service remains at the original location and the sessions remain active. You must examine the services and stop them if that is what you want to do.
When you relocate a service, it starts at the new location before it stops at the original location. Oracle Clusterware can start that new instance or pluggable database as a dependency. When specified, the
-drain_timeout
and
-stopoption
parameters override the service attributes.
Stopping Services
You can use the srvctl stop service
command to stop all services on a node, all services offered by a database, all services offered by a pluggable database, or all services offered on an instance or within a given server pool.
You can also supply a list of services (a subset of all services) that you want to stop to the srvctl stop service
command, and you can also restrict the srvctl stop service
command to stop only the parallel query service by specifying the
-pq parameter.
The following examples illustrate how you can stop services:
• To stop all of the services offered by a single pluggable database:
$ srvctl stop service –db myRACCDB01 –pdb myPDB01 –drain_timeout 15 –stopoption
TRANSACTIONAL
To stop all services on a given database and any of its pluggable databases:
$ srvctl stop service –db myRACDB –drain_timeout 15 –stopoption IMMEDIATE
To stop only a subset of the services offered by a pluggable database:
Ensuring Application Continuity 6-13
Fast Application Notification
$ srvctl stop service –db myRACDB –pdb myPDB01 –service
"myFirstService,mySecondService,
myThirdService" –drain_timeout 60 –stopoption IMMEDIATE
Note:
If you use the
–wait YES
SRVCTL command line parameter, then the
–stopoption
parameter is not enforced until the entire drain timeout interval has expired, even if all of the sessions have exited prior to this interval completing.
Fast Application Notification High Availability Events
This section describes the information delivered in the FAN event to a callout program.
FAN event types are listed following the example, and
Table 6-2 describes name-value
pairs for the event parameters. The event type is always the first entry when you receive FAN information through a callout, as in the following example:
SERVICEMEMBER VERSION=1.0
service=test.company.com database=ractest
instance=ractest11 host=ractest1_host0343_1 status=up reason=FAILURE
timestamp=2012-02-01 22:06:02 timezone=-07:00 db_domain=company.com
Note that the preceding example displays as one line.
FAN event types include:
DATABASE
INSTANCE
NODE
SERVICE
SERVICEMEMBER
SRV_PRECONNECT
SERVICEMETRICS
The
DATABASE
and
INSTANCE
types list the default database service as
DB_UNIQUE_NAME
.
All events except for
NODE
events include a db_domain
field.
Events of
SERVICEMETRICS
type are load balancing advisory events.
See Also:
for more information about load balancing events
Table 6-2 Event Parameter Name-Value Pairs and Descriptions
Parameter
VERSION database instance
Description
Version of the event record. Used to identify release changes.
The unique name of the database supporting the service; matches the initialization parameter value for
DB_UNIQUE_NAME
, which defaults to the value of the
DB_NAME
initialization parameter.
The name of the instance that supports the service; matches the
ORACLE_SID
value.
6-14 Oracle Real Application Clusters Administration and Deployment Guide
Fast Application Notification
Table 6-2 (Cont.) Event Parameter Name-Value Pairs and Descriptions
Parameter
host service
Description
The name of the node that supports the service or the node that has stopped; matches the node name known to Cluster
Synchronization Services (CSS).
The service name; matches the name of the service as listed in
DBA_SERVICES
and is domain-qualified as appropriate. Refer to the following examples:
SERVICEMEMBER VERSION=1.0 service=swingbench
database=orcl instance=orcl_2 host=rwsbj13 status=up
reason=USER card=1 timestamp=2012-05-29 17:26:37
timezone=-07:00 db_domain=
SERVICEMEMBER VERSION=1.0 service=swingbench.example.com
database=orcl instance=orcl1 host=rwsbj09 status=up
reason=USER card=2 timestamp=2012-07-03 17:29:28
timezone=-07:00 db_domain=example.com
SERVICEMEMBER VERSION=1.0 service=swingbench.example.com
database=orcl instance=orcl2 host=rwsbj10 status=up
reason=USER card=1 timestamp=2012-07-03 17:29:18
timezone=-07:00 db_domain=example.com
status reason
Values are
UP
,
DOWN
,
NODEDOWN
(this only applies to the
NODE event type),
NOT_RESTARTING
,
PRECONN_UP
,
PRECONN_DOWN
, and
UNKNOWN
.
Notes:
• When the node is down, the status is
NODEDOWN
, as opposed to
DOWN
for other event types.
• When
STATUS=NODEDOWN
and
REASON=MEMBER_LEAVE
, a node has failed and is no longer part of the cluster.
• When
STATUS=NODEDOWN
and
REASON=PUBLIC_NW_DOWN
, the node is up but it is unreachable because the public network is down.
• Multiple public networks are supported by Oracle
Clusterware. The FAN event reflects this fact.
AUTOSTART
,
BOOT
,
DEPENDENCY
,
FAILURE
,
MEMBER_LEAVE
,
PUBLIC_NW_DOWN
,
USER
.
Notes:
• For
DATABASE
and
SERVICE
event types,
REASON=AUTOSTART
if, when the node started, the
AUTO_START
resource attribute was set to restore, and the resource was offline before the node started.
• For
DATABASE
and
SERVICE
event types,
REASON=BOOT
if, when the node started, the resource started because it was online before the node started.
• For SRVCTL and Oracle Enterprise Manager operations,
REASON=USER
describes planned actions for such operations as draining work.
Ensuring Application Continuity 6-15
Fast Application Notification
Table 6-2 (Cont.) Event Parameter Name-Value Pairs and Descriptions
Parameter
cardinality
Description
The number of service members that are currently active; included in all
SERVICEMEMBER UP
events.
Following is an example of
SERVICEMEMBER UP
event:
SERVICEMEMBER VERSION=1.0 service=swingbench.example.com
database=orcl instance=orcl_2 host=mjkbj09 status=up reason=USER card=1 timestamp=2012-07-12 14:46:46 timezone=-07:00 db_domain=example.com
incarnation
For
NODEDOWN
events; the new cluster incarnation. This value changes each time a member joins or leaves the cluster.
Following is an example of a
NODEDOWN
event:
NODE VERSION=1.0 host=stru09 incarn=175615351 status=down reason=member_leave timestamp=27-Jul-2010 14:49:32 timezone=-07:00 timestamp timezone
The time according to Oracle Clusterware that an event occurs.
The time zone of Oracle Clusterware where the event occurred, given as GMT +/-hh:mm.
Some of the FAN event record parameters have values that correspond to values returned by the
SYS_CONTEXT
function using the default namespace
USERENV
, as
.
Table 6-3 FAN Parameters and Matching Session Information
FAN Parameter
SERVICE
DATABASE_UNIQUE_NA
ME
INSTANCE
CLUSTER_NODE_NAME
Matching Session Information
sys_context('userenv', 'service_name') sys_context('userenv', 'db_unique_name') sys_context('userenv', 'instance_name') sys_context('userenv', 'server_host')
Subscription to High Availability Events
Oracle RAC uses FAN to notify applications about configuration changes and the current service level that is provided by each instance where the service is enabled. If you are using an OCI client or an ODP.NET client to receive FAN events, then you must enable the service used by that client to access the alert notification queue by using SRVCTL with the
-notification
parameter.
Using Fast Application Notification Callouts
FAN callouts are server-side executables that Oracle RAC executes immediately when high availability events occur.
You can use FAN callouts to automate activities when events occur in a cluster configuration, such as:
6-16 Oracle Real Application Clusters Administration and Deployment Guide
About Application Continuity
• Opening fault tracking tickets
• Sending messages to pagers
• Sending e-mail
• Starting and stopping server-side applications
• Maintaining an uptime log by logging each event as it occurs
• Relocating low-priority services when high priority services come online
To use FAN callouts, place an executable in the
Grid_home/racg/usrco
directory on every node that runs Oracle Clusterware. The executable must be able to run standalone when called, with optional arguments, from another program. The following is an example of the
Grid_home/racg/usrco/callout.sh
callout:
#! /bin/bash
FAN_LOGFILE= [your_path_name]/admin/log/'hostname'_uptime'.log
echo $* "reported="'date' >> $FAN_LOGFILE &
The previous example produces output similar to the following:
NODE VERSION=1.0 host=sun880-2 incarn=23 status=nodedown reason=public_nw_down timestamp=08-Oct-2012 04:02:14 timezone=-08:00 reported=Fri Oct 8 04:02:14 PDT 2012
The contents of a FAN event record matches the current session of the user logged on
to the database, as shown in Table 6-3
. The user environment (
USERENV
) information is also available using OCI connection handle and descriptor attributes (using
OCIAttrGet()
). Use this information to take actions on sessions that match the FAN event data.
See Also:
for information about the callout and event details
In general, events are only posted to user callouts on the node from which the event originated. For example, if the database on node1
goes down, then the callout is posted to node1
, only. The only exceptions to this are node down and VIP down events—these events are posted to all nodes, regardless of from where they originated.
Related Topics:
Oracle Call Interface Programmer's Guide
About Application Continuity
Application Continuity masks many recoverable database outages (when replay is successful) from applications and users by restoring the database session: the full session, including all states, cursors, variables, and the last transaction if there is one.
Application Continuity addresses the problem that arises when an application is trying to access the database and the database instance becomes unavailable due to an unplanned or planned outage (timeout, network outage, instance failure, repair, configuration change, patch apply, and so on). Without Application Continuity in place, database recovery does not mask outages to applications and end users. In such scenarios, developers and users must cope with exception conditions, and users can be left not knowing what happened to their funds transfers, time sheets, orders, bill
Ensuring Application Continuity 6-17
About Application Continuity payments, and so on. Users might lose screens of uncommitted data, and must log in again and reenter that data. In the worst cases, the administrator might be forced to restart the middle tier to recover from an overwhelming number of logins.
With Application Continuity, if the database instance became unavailable, then
Application Continuity attempts to rebuild the session and any open transactions using the correct states; and if the transaction committed and need not be resubmitted, then the successful return status is returned to the application. If replay is successful, then the request can continue safely without risk of duplication. If replay cannot restore data that the application has already processed and potentially made decisions on, then the database rejects the replay and the application receives the original error.
Application Continuity performs the recovery of in-flight transactions and database session state, while ensuring the transaction idempotence provided by Transaction
Guard. Each database session is tagged with a logical transaction ID (LTXID), so the database recognizes whether each replay committed any transactions, and if it did commit any transactions, whether the work also ran to completion. While Application
Continuity attempts to replay, the replay appears to the application as a delayed execution, or the application receives the commit response for the original transaction
(if the last transaction had completed before the outage).
Application Continuity is supported for Oracle RAC and Oracle Active Data Guard. It is supported for both non-consolidated databases and Multitenant databases (with failover at the pluggable database level). It is not currently supported for Golden Gate,
Logical Standby, third-party replication solutions, or DML redirection if using Oracle
Active Data Guard.
Related Topics:
Actions for Using Application Continuity
Key Concepts for Application Continuity
This section describes several terms and concepts that you must understand to use
Application Continuity.
The following terms are used throughout this chapter:
request
A request is a unit of work submitted from the application, such as a transaction. A request typically corresponds to the SQL and PL/SQL, and other database calls, of a single web request on a single database connection, and it is generally demarcated by the calls made to check-out and check-in the database connection from a connection pool.
recoverable error
A recoverable error is an error that arises due to an external system failure, independent of the application session logic that is executing, such as a lost or invalid connection. Recoverable errors occur following planned and unplanned outages of foregrounds, networks, nodes, storage, and databases. The application receives an error code that can leave the application not knowing the status of the last operation submitted. Application Continuity reestablishes database sessions and resubmits the pending work for the class of recoverable errors.
6-18 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Application Continuity does not resubmit work following call failures due to nonrecoverable errors. An example of a nonrecoverable error that would not be replayed is submission of invalid data values.
commit outcome
A transaction is committed by updating its entry in the transaction table. Oracle
Database generates a redo-log record corresponding to this update and writes out this redo-log record. Once this redo-log record is written out to the redo log on disk, the transaction is considered committed at the database. From the client perspective, the transaction is considered committed when an Oracle message (called the commit
outcome
), generated after that redo is written, is received by the client. However, if a
COMMIT
has been issued, then the
COMMIT
failure message cannot be retrieved if it is not received by the client or the application.
mutable functions
Mutable fuctions are non-deterministic functions that can obtain a new value every time they are called, and thus their results can change frequently. Mutable functions cause a problem for replay because the results can change at replay. Consider
sequence
.NEXTVAL
and
SYSDATE
, often used in key values. If a primary key is built with values from these function calls, and is used in later foreign keys or other binds, at replay the same function result must be returned.
Application Continuity provides mutable object value replacement at replay for granted Oracle function calls to provide opaque bind-variable consistency. If the call uses database functions that are mutable, including sequence
.NEXTVAL
,
SYSDATE
,
SYSTIMESTAMP
, and
SYSGUID
, the original values returned from the function execution are saved and are reapplied at replay.
session state consistency
After a
COMMIT
statement has executed, if state was changed in that transaction, it is not possible to replay the transaction to reestablish that state if the session is lost.
When configuring Application Continuity, the applications are categorized depending on whether the session state after the initial setup is static or dynamic, and thus whether it is correct to continue past a
COMMIT
operation within a request.
• A session has dynamic state if the session state changes are not fully encapsulated by the initialization, and cannot be fully captured by FAILOVER_RESTORE or in a callback at failover. After the first transaction completes, failover is internally disabled until the next request begins. Session state may change during the course of the request.
• A session has a static state if all session state changes (for example, NLS settings and PL/SQL package state) occur as part of initialization, and can be encapsulated by FAILOVER_RESTORE or in a callback at failover. Static applications are those that were able to use Transparent Application Failover (TAF) before Application
Continuity. Session state does not change during the course of the request.
Application Continuity Operation and Usage
This section explains how Application Continuity works, and how you can use it in applications.
This section includes the following topics:
•
How Application Continuity Works for Applications
Ensuring Application Continuity 6-19
Application Continuity Operation and Usage
•
Actions for Using Application Continuity
•
Mutable Functions and Application Continuity
•
•
How Application Continuity Works for Applications
If a recoverable error occurs and if you enabled replay, then Application Continuity attempts recovery of the database session.
The following figure is a graphical representation of how Application Continuity works.
Figure 6-1 Application Continuity
1 Request 5 Response
UCP,
ODP.NET,
WebLogic,
OCI Session
Pool,
Tuxedo,
JDBC, and
OCI drivers
2 Calls
3 Fan or error 4 Replay
5 User
Calls
Database
Storage
To attempt to recover a database session following a recoverable error, Application
Continuity performs the following steps:
6-20 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Note:
The steps to recover a database session apply for both unplanned and planned outages, although specific steps vary depending on the type of outage.
1.
2.
3.
4.
The client application makes a request, which is passed to a middle tier (such as the Universal Connection Pool (UCP), ODP.NET, WebLogic Server, OCI session pool, Tuxedo, JDBC and OCI drivers, or third-party pool using UCP), or directly to the database using the JDBC replay driver or OCI driver.
The JDBC replay driver or OCI driver issues each call in the request.
A FAN unplanned or planned down interrupt or recoverable error occurs.
FAN/FCF then aborts the dead physical session.
Application Continuity begins the replay and does the following:
a.
b.
c.
Replaces the dead physical session with a new clean session.
Prepares for replay by using Transaction Guard to determine the outcome of the in-flight transaction, if one was open.
FAILOVER_RESTORE=LEVEL1
restores the common initial session states.
Application Continuity uses a labeling callback or reconnect callback if an application also sets initial session states that are not provided by
FAILOVER_RESTORE.
d.
e.
Rebuilds the database session, recovering the transactional and nontransactional states, and validating at each step that the data and messages seen by the client driver are the same as those that the client may have seen and used to make a decision.
Ends the replay and returns to runtime mode.
f.
Submits the last queued call.
This is the last call made when the outage was discovered. During replay, only this call can execute a
COMMIT
. A
COMMIT
midway through rebuilding the session aborts replay (excluding autonomous transactions).
5.
The response is returned to the application.
If replay succeeded, then the application can continue with the problem masked.
If not, then the application must handle the original error.
The behavior of Application Continuity after a communication failure depends on the
Oracle products and technologies involved. For example:
• If you use Oracle RAC or an Oracle Active Data Guard farm, then, after the connection is reestablished on another running instance, Application Continuity attempts to rebuild the session and replay the last transaction if there is one in flight.
• If you use Oracle Active Data Guard and fail over to a standby site, then
Application Continuity connects to the failover instance and attempts to rebuild the session and replay the last transaction there, if a transaction was in-flight.
(Application Continuity does not replay if the Oracle Active Data Guard switchover or failover has lost data, and if this is not an Oracle Active Data Guard reader farm with approved lags.)
Ensuring Application Continuity 6-21
Application Continuity Operation and Usage
• If you are using Oracle RAC or Oracle RAC One Node and not using Oracle
Active Data Guard, and if an outage causes a break in all public networks or causes the database or database session to shut down briefly, then Application
Continuity attempts to rebuild the session and replay the last transaction (if a transaction was in flight) against the database after connectivity is restored.
Related Topics:
Using Application Continuity for Planned Maintenance
For planned maintenance, the recommended approach is to drain requests from Oracle connection pools in combination with Application
Continuity for those requests that do not complete. Instances do need to be stopped to switch over to the patched software.
Actions for Using Application Continuity
Application Continuity masks outages with few or no application changes when you use the Oracle integrated stack.
Application Continuity is available for general use with the following Oracle technologies:
• ODP.NET, Unmanaged Driver
• OCI Session Pool
• Universal Connection Pool
• WebLogic Server
• JDBC Thin Oracle replay driver
• Oracle Tuxedo
• SQL*Plus
Application Continuity for Java is embedded in the Universal Connection Pool,
WebLogic data sources, including non-XA and XA data sources, and is available with the thin JDBC replay driver, standalone (which is a JDBC replay driver without Oracle connection pools, such as Apache Tomcat or a custom Java connection pool).
Application Continuity for OCI is embedded in SQL*Plus, OCI Session Pool. Oracle
Tuxedo for non XA data sources, and ODP.NET, Unmanaged Provider.
Application Continuity is embedded in Oracle connection pools. When you use the
Oracle connection pools, request boundaries are implicitly marked at check-out and check-in, delimiting the size of each replay. When using third-party connection pools, use UCP if Java, or you can add request boundaries, which are included on the JDK9 standard.
Support for Application Continuity is integrated into many Oracle applications, so the features in such applications are used automatically if you set the Application
Continuity-related service attributes. For all applications, follow the steps described in this section.
The main actions for ensuring transparent replay for an application are the following:
1.
Only if using Java, determine whether the application uses Oracle JDBC concrete classes. For Application Continuity to be used, the deprecated concrete classes must be replaced.
6-22 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Use the
-acchk
parameter with the ORAchk utility to verify whether an application has any concrete classes. Use a connection without Application
Continuity if there is anything that should not be replayed. (Most applications will be replayable.)
See Also:
Oracle Autonomous Health Framework User's Guide
for more information about ORAchk
2.
3.
Ensure that you have the necessary CPU and memory resources.
•
CPU
: Application Continuity is managed on the client and server sides and requires minimal CPU overhead to operate.
At the client, CPU is used to build proxy objects and for garbage collection
(GC).
At the server, CPU is used for validation. CPU overhead is reduced for platforms with current Intel and Sparc chips where validation is assisted in the hardware.
•
Memory
: When using Application Continuity, the replay driver requires more memory than the base driver because the calls are retained until the end of a request. At the end of the request, the calls are released to the garbage collector. This action differs from the base driver that releases closed calls.
The memory consumption of the replay driver depends on the number of calls per request. If this number is small, then the memory consumption of the replay driver is less, and comparable to the base driver.
To obtain the best performance, you must set the same value for both the
-
Xmx
and
-Xms
parameters on the client. For example, if there is sufficient memory, then allocate 4 to 8 GB (or more) of memory for the Virtual Machine
(VM), for example, by setting
-Xms4g
for 4 GB. If the
-Xms
parameter has a lower value, then the VM also uses a lower value from the operating system, and performance might suffer and garbage collection operations increase.
Determine whether the application borrows and returns connections from the connection pool, for example WebLogic Server Pool, Universal Connection Pool,
OCI Session Pool, Oracle Tuxedo request, or ODP.NET connection pool, for each request, or whether to add beginRequest
and endRequest
APIs to the application's own connection pool to identify request boundaries for Java, only.
Important:
Do not use the beginRequest
and endRequest
Java API calls anywhere other than at request boundaries (borrow and return connections from your connection pool). endRequest
indicates that the request is complete, and that it is now stateless. Replay starts from the next beginRequest
. If there is prior state, it must be reestablished using
FAILOVER_RESTORE
or callback.
4.
Application Continuity replays your states, all states in a request. If the application sets states before vending connections,
FAILOVER_RESTORE
or a callback is needed. When using Oracle WebLogic Server or the Universal
Connection Pool, use
FAILOVER_RESTORE
or connection labeling. When using
OCI session pool, Oracle Tuxedo or ODP.NET, use
FAILOVER_RESTORE
, and only add the TAF callback if it is needed. The labeling is used for both runtime and replay.
Ensuring Application Continuity 6-23
Application Continuity Operation and Usage
5.
6.
7.
8.
Determine whether the application requires, and therefore needs to configure keeping original values for,
SYSDATE
,
SYSTIMESTAMP
, and
SYS_GUID
and sequences during failover.
Assess the application style for the session_state_consistency
value, and set the appropriate value on the service:
• If session_state_consistency
is
Dynamic
, the application changes the environment or settings during the request. Replay is disabled after the first
COMMIT
until the beginning of the next request.
Dynamic
is the default mode, appropriate for most applications.
• If session_state_consistency
is
Static
, the application never changes the session state after initial setup. This mode is typical for database agnostic applications that do not use PL/SQL state and do not use
ALTER
part-way through transactions. Use this mode with caution, and only for "static" applications.
Determine if any requests in the application should not be replayed.
For example, replay may need to be disabled for requests using external PL/SQL actions.
Follow these configuration guidelines:
• Use Oracle Database 12c release 1 (12.1.0.1), or later, for Java. Use Oracle
Database 12c release 2 (12.2), or later, for OCI-based applications..
• For .NET applications, use ODP.NET, Unmanaged Driver 12.2, or later, connecting to an Oracle Database 12c Release 2 (12.2) or later. By default,
Application Continuity is enabled for ODP.NET applications in this configuration.
• For Java-based applications, use Universal Connection Pool 12.1 (or later) or
WebLogic Server 12.1.2 (or later) configured with the JDBC Replay data source; or for third party applications, including third party JDBC pools, use
JDBC replay driver. For IBM WebSphere, Apache Tomcat, RedHat Spring, and custom Java solutions, the most effective solution is to use UCP as the pooled data source.
Custom Java pools and standalone Java applications can also use the JDBC
Replay data source directly. When using custom Java pools and standalone applications, add the beginRequest
and endRequest
calls.
• If the application does not borrow and return from the Oracle connection pools, explicitly mark request boundaries. For example, if using custom JDBC pools, or other pools, then call beginRequest
at check-out and call endRequest
at check-in. These APIs can also be used for standalone JDBC applications without a connection pool.
• Enable FAN for fast interrupt on errors. This is essential to eliminate a TCP hang occurring before the failover can start. In 12.2 FAN is built into the JDBC and OCI drivers and is on by default for Java.
• Use a database service to connect; never use a SID or an instance name, or the administration service that is the
DB_NAME
or
DB_UNIQUE_NAME
.
• Use a connection string that sets retries for new incoming connections and a delay between these retries.
6-24 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Recommended format supporting automatic configuration of FAN: alias =(DESCRIPTION =
(CONNECT_TIMEOUT=90) (RETRY_COUNT=20)(RETRY_DELAY=3)
(TRANSPORT_CONNECT_TIMEOUT=3)
(ADDRESS_LIST =
(LOAD_BALANCE=on)
( ADDRESS = (PROTOCOL = TCP)(HOST=primary-scan)(PORT=1521)))
(ADDRESS_LIST =
(LOAD_BALANCE=on)
( ADDRESS = (PROTOCOL = TCP)(HOST=secondary-scan)(PORT=1521)))
(CONNECT_DATA=(SERVICE_NAME = gold-cloud)))
• For the service, set
FAILOVER_TYPE
to
TRANSACTION
,
COMMIT_OUTCOME
to
TRUE
, and
Notification
to
TRUE
. Optionally to find the best connections to use, set
GOAL
to
SERVICE_TIME
and
CLB_Goal
to
Short
.
• Grant permission on the Transaction Guard package,
DBMS_APP_CONT
, to the database users that fail over using Application Continuity, as follows:
GRANT EXECUTE ON DBMS_APP_CONT TO user_name;
• Use Application Continuity Check Coverage (with the ORAchk utility) to report the percentage of requests that are fully protected by Application
Continuity, and the location of those requests that are not fully protected. Use this coverage check before deployment and after application changes.
Developers and management will know how well protected an application release is from failures of the underlying infrastructure. If there is a problem, then it can be fixed before the application is released, or waived knowing the level of coverage.
See Also:
•
Oracle Data Provider for .NET Developer's Guide for Microsoft Windows
for more information about .NET applications development.
•
Oracle Database JDBC Developer’s Guide
for more information about developing applications that include Application Continuity for Java
This section includes the following topics:
•
When Application Continuity is Transparent
•
Configuring Oracle Application Continuity
•
Configuring Oracle Database for Application Continuity
•
Establishing the Initial State Before Application Continuity Replays
•
Delaying the Reconnection in Application Continuity
•
Using Application Continuity with SQL*Plus
•
Using Application Continuity for Planned Maintenance
•
Running Without Application Continuity
Ensuring Application Continuity 6-25
Application Continuity Operation and Usage
•
Disabling Replay in Application Continuity
•
Terminating or Disconnecting a Session Without Replay
Related Topics:
Oracle Autonomous Health Framework User's Guide
Mutable Functions and Application Continuity
When a request is replayed, the default and desired treatment of mutable objects can vary.
Session state consistency describes how non-transactional state is changed during a request.
Session state consistency describes how non-transactional state is changed during a request.
Disabling Replay in Application Continuity
By default, replay occurs following a recoverable error.
Oracle Data Provider for .NET Developer's Guide for Microsoft Windows
Oracle Database JDBC Developer’s Guide
Oracle Universal Connection Pool Developer’s Guide
Oracle Database 2 Day + Real Application Clusters Guide
Oracle ORAchk and EXAchk User’s Guide
When Application Continuity is Transparent
Application Continuity is transparent (no application code changes) for ODP.NET
applications, OCI applications, Tuxedo applications, and J2EE applications that use standard JDBC, and that use Oracle connection pools (UCP, OCI, or ODP), and
SQL*Plus. For applications with external actions (for example, autonomous transactions or using
UTL_HTTP
to issue an SOA call), Application Continuity is transparent when the application is satisfied with replaying external actions, such as resending email, auditing, and transferring a file for example.
For non-Oracle pools, including third-party Java containers, in which Application
Continuity is not transparent, the following infrastructure changes may be needed:
• If the connection pool or container does not use an Oracle connection pool, then many third parties fully support replacing the connection pool with the Universal
Connection Pool. This includes IBM WebSphere and Apache Tomcat.
Alternatively—for Java applications, only—the application can add its own request boundaries.
• If the application has requests that the application does not want repeated, then the application can explicitly call an API to disable replay for those requests. The simplest way to do this is to use a connection to a service that does not have
FAILOVER_TYPE
set to
TRANSACTION
. Such calls are likely to be isolated to one or a few specialized pieces of application code.
6-26 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Configuring Oracle Application Continuity
If you are using Java, then you must use the oracle.jdbc.replay.OracleDataSourceImpl
data source to obtain JDBC connections.
This data source supports all the properties and configuration parameters of all the
Oracle JDBC data sources, for example, the oracle.jdbc.pool.OracleDataSource
.
For OCI based applications including SQL*Plus and ODP.NET, the OCI driver 12.2, and later, supports Application Continuity.
You must remember the following points while using the connection URL:
• If the
REMOTE_LISTENER
setting for the database does not match the addresses in the
ADDRESS_LIST
at the client, then it does not connect, showing services cannot be found
. So, the
REMOTE_LISTENER
setting for the database must match the addresses in the
ADDRESS_LIST
at the client:
– If
REMOTE_LISTENER
is set to the SCAN names, then the
ADDRESS_LIST must use SCAN VIPs.
– If the connect string uses the SCAN Name, then
REMOTE_LISTENERS
must be set to the SCAN name.
– If the connect string uses an
ADDRESS_LIST
of host VIPs, then
REMOTE_LISTENERS
must be set to an address list that includes all SCAN
VIPs and all host VIPs
Note:
Use SCAN for location independence, so that you do not need to reconfigure the client when you add or delete nodes, or when databases change to running on different nodes.
• Set
RETRY_COUNT
,
RETRY_DELAY
,
CONNECT_TIMEOUT
, and
TRANSPORT_CONNECT_TIMEOUT
parameters in the connection string. These settings improve acquiring new connections at runtime, at replay, and during work drains for planned outages.
The
CONNECT_TIMEOUT
parameter is equivalent to the
SQLNET.OUTBOUND_CONNECT_TIMEOUT
parameter in the sqlnet.ora
file and applies to the full connection. The
TRANSPORT_CONNECT_TIMEOUT
parameter applies per address.
Set
CONNECT_TIMEOUT
to a high value to prevent an overabundance of log ins.
Low values can result in log in storms to the application or server pool cancelling and retrying. Do not set
(RETRY_COUNT+1)*RETRY_DELAY
or
CONNECT_TIMEOUT
larger than your response time SLA. The application must either connect or receive an error within the response time SLA.
These are general recommendations for configuring the connections for high availability. Do not use Easy*Connect because this has no high-availability capabilities.
When the connect string uses host VIPs, then
REMOTE_LISTENERS
must include host VIPs. When the connect string uses the SCAN name, then
Ensuring Application Continuity 6-27
Application Continuity Operation and Usage
REMOTE_LISTENERS
must be set to the SCAN name, or include the SCAN VIPs and the host VIPs. Therefore,
REMOTE_LISTENERS
must be set to the SCAN name unless any clients use host VIPs in their connect strings, in which case
REMOTE_LISTENERS
must be set to an
ADDRESS_LIST
of all SCAN VIPs and all host VIPs.
Following is an example of TNS entry. This is the required TNS format for ONS
(the transport system for FAN) to be auto configured. FAN is recommended with
Application Continuity to provide the immediate detection.
alias =(DESCRIPTION =
(CONNECT_TIMEOUT=120) (RETRY_COUNT=20)(RETRY_DELAY=3)
(TRANSPORT_CONNECT_TIMEOUT=3)
(ADDRESS_LIST =
(LOAD_BALANCE=on)
( ADDRESS = (PROTOCOL = TCP)(HOST=primary-scan)(PORT=1521)))
(ADDRESS_LIST =
(LOAD_BALANCE=on)
( ADDRESS = (PROTOCOL = TCP)(HOST=secondary-scan)(PORT=1521)))
(CONNECT_DATA=(SERVICE_NAME = gold-cloud)))
Related Topics:
Oracle Database Net Services Reference
Oracle Data Provider for .NET Developer's Guide for Microsoft Windows
Configuring Oracle Database for Application Continuity
Your Oracle Database configuration must include the following to use Application
Continuity:
• If you are using Oracle Real Application Clusters (Oracle RAC) or Oracle RAC
One Node, Oracle Data Guard, or Oracle Active Data Guard, then ensure that
FAN is configured with Oracle Notification System (ONS) to communicate with
Oracle Database 12c pools and drivers.
• Set the required properties on the service for replay and load balancing. For example, set:
–
FAILOVER_TYPE = TRANSACTION
: For using Application Continuity
–
REPLAY_INITIATION_TIMEOUT = n
: For setting the duration, in seconds, to allow replay to start (where the value of
n
can be, for example, 60, 300, 900, or 1800, depending on your needs)
–
FAILOVER_RETRIES = 30
: For specifying the number of connection retries for each replay
–
FAILOVER_DELAY = 10
: For specifying the delay in seconds between connection retries
–
GOAL = SERVICE_TIME
: If you are using Oracle RAC or Oracle Global Data
Services, then this is a recommended setting
–
CLB_GOAL = SHORT
: If you are using Oracle RAC or Oracle Global Data
Services, then this is a recommended setting
–
COMMIT_OUTCOME = TRUE
: For using Transaction Guard
6-28 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
–
FAILOVER_RESTORE = LEVEL1
: To automatically restore the states that are preset on the connection pool before the application uses it—including
AUTOCOMMIT state (for Java and SQL*Plus), NLS states, and TAGS
(Module, action, client id, esid) states.
• Grant permission on the Transaction Guard package,
DBMS_APP_CONT
, to the database users that fail over using Application Continuity, as follows:
GRANT EXECUTE ON DBMS_APP_CONT TO user_name;
•
Do not use
the default database service corresponding to the
DB_NAME
or
DB_UNIQUE_NAME
. Also, do not use the database service for high availability, because this service cannot be enabled and disabled, and cannot be relocated on
Oracle RAC or switched over to Oracle Data Guard. This service is reserved for
Oracle Enterprise Manager Cloud Control (Cloud Control) and for DBAs.
Establishing the Initial State Before Application Continuity Replays
Some applications set an initial state for the connection before allowing applications to use the connection.
Application Continuity must establish this initial state before replay starts. For these applications,
FAILOVER_RESTORE
restores common states listed here. If the states that the application presets are not listed here, and the application needs initial states, then an additional callback needs to be added.
Examples of states that can be preset include:
• PL/SQL package state
• NLS Setting
• Optimizer setting
During a request, Application Continuity reestablishes the entire state for the request.
This pre-requisite is for the initial state before Application Continuity starts replaying.
A callback is not required if
FAILOVER_RESTORE
restores all required states, which is the case for almost all applications.
For applications that set state only at the beginning of a request, or for stateful applications that gain performance benefits from using connections with a preset state, choose one of these options:
•
•
FAILOVER_RESTORE = NONE and No Callback
•
•
Connection Initialization Callback
FAILOVER_RESTORE = LEVEL1
Setting
FAILOVER_RESTORE
to
LEVEL1
automatically restores common state initial settings before replaying the request.
The states restored include the following:
• NLS_CALENDAR
• NLS_CURRENCY
Ensuring Application Continuity 6-29
Application Continuity Operation and Usage
• NLS_DATE_FORMAT
• NLS_DATE_LANGUAGE
• NLS_DUAL_CURRENCY
• NLS_ISO_CURRENCY
• NLS_LANGUAGE
• NLS_LENGTH_SEMANTICS
• NLS_NCHAR_CONV_EXCP
• NLS_NUMERIC_CHARACTER
• NLS_SORT
• NLS_TERRITORY
• NLS_TIME_FORMAT
• NLS_TIME_TZ_FORMAT
• TIME_ZONE (OCI, ODP.NET 12201)
• NLS_TIMESTAMP_FORMAT
• NLS_TIMESTAMP_TZ_FORMAT
• CURRENT_SCHEMA
• MODULE
• ACTION
• CLIENT_ID
• ECONTEXT_ID
• ECONTEXT_SEQ
• DB_OP
• AUTOCOMMIT states (for Java and SQL*Plus)
• CONTAINER (PDB) and SERVICE for OCI and ODP.NET
The following are not supported by the THIN driver, so are excluded from the autorestoration option:
• NLS_COMP
• CALL_COLLECT_TIME
• CLIENT_INFO
FAILOVER_RESTORE = NONE and No Callback
In this scenario, the application does not assume any state when borrowing a connection from a pool, or uses UCP or WebLogic labels to reestablish the initial state.
6-30 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Connection Labeling
Connection Labeling is a generic pool feature that is recommended for its excellent performance. When Connection Labeling is present, Application Continuity uses it.
Since the Connection Labeling is recreating the state, FAILOVER_RESTORE can be set to NONE.
This scenario is applicable to Universal Connection Pool (UCP) and Oracle WebLogic server. The application can be modified to take advantage of the preset state on connections. Connection Labeling APIs determine how well a connection matches, and use a callback to populate the gap when a connection is borrowed.
Related Topics:
Oracle Universal Connection Pool Developer’s Guide
Connection Initialization Callback
In this scenario, the replaying driver (JDBC or OCI) uses an application callback to set the initial state of the session during runtime and replay. The JDBC replay driver provides a connection initialization callback interface and methods to register and unregister connection initialization callbacks in the oracle.jdbc.replay.OracleDataSource
interface. For OCI and ODP.NET, register the TAF callback.
When registered, the initialization callback is executed at each successful reconnection following a recoverable error. An application is responsible for ensuring that the initialization actions are the same as that on the original connection before failover. If the callback invocation fails, then replay is disabled on that connection. Use the connection initialization callback only when the application has not implemented UCP and WebLogic Connection Labeling and the state cannot be restored automatically by setting
FAILOVER_RESTORE=LEVEL1
.
Delaying the Reconnection in Application Continuity
By default, when Application Continuity initiates a failover, the driver attempts to recover the in-flight work at an instance where the service is available.
For recovering the work, the driver must establish a good connection with the instance. This reconnection can take some time if the database or the instance must be restarted before the service is relocated and published. So, the failover must be delayed until the service is available from another instance or database.
You must use the
FAILOVER_RETRIES
and
FAILOVER_DELAY
parameters to manage connecting and reconnecting. These parameters can work well in conjunction with a planned outage, for example, an outage that may make a service unavailable for several minutes. While setting the
FAILOVER_DELAY
and
FAILOVER_RETRIES parameters, check the value of the
REPLAY_INITIAITION_TIMEOUT
parameter first.
The default value for this parameter is 900 seconds. A high value for the
FAILOVER_DELAY
parameter can cause replay to be canceled.
Parameter Name
FAILOVER_RETRIES
FAILOVER_DELAY
Possible Value Default Value
Positive integer zero or above 30
Time in seconds 3
The following examples show various failover scenarios:
Ensuring Application Continuity 6-31
Application Continuity Operation and Usage
•
Creating Services on Oracle RAC with Application Continuity
•
Modifying Services on Single-instance Databases to use Application Continuity
Creating Services on Oracle RAC with Application Continuity
You can create services on Oracle RAC that utilize Application Continuity.
If you are using Oracle RAC or Oracle RAC One Node, then use SRVCTL to create services, as follows:
For policy-managed databases:
$ srvctl add service -db codedb -service GOLD -serverpool ora.Srvpool -clbgoal SHORT
-rlbgoal SERVICE_TIME
-failover_restore LEVEL1 -failoverretry 30 -failoverdelay 10 -commit_outcome TRUE failovertype TRANSACTION
-replay_init_time 1800 -retention 86400 -notification TRUE
For administrator-managed databases:
$ srvctl add service -db codedb -service GOLD -preferred serv1 -available serv2 clbgoal SHORT
-rlbgoal SERVICE_TIME -failover_restore LEVEL1 -failoverretry 30 -failoverdelay 10
-commit_outcome TRUE
-failovertype TRANSACTION -replay_init_time 1800 -retention 86400 -notification
TRUE
Modifying Services on Single-instance Databases to use Application Continuity
If you are using a single-instance database, then use the
DBMS_SERVICE
package to modify services as follows:
DECLARE params dbms_service.svc_parameter_array;
BEGIN params('FAILOVER_TYPE'):='TRANSACTION'; params('REPLAY_INITIATION_TIMEOUT'):=1800; params('RETENTION_TIMEOUT'):=86400; params('FAILOVER_DELAY'):=10; params('FAILOVER_RETRIES'):=30; params('FAILOVER_RESTORE'):='LEVEL1'; params('commit_outcome'):='true'; params('aq_ha_notifications'):='true'; dbms_service.modify_service('[your service]',params);
END;
/
Using Application Continuity with SQL*Plus
Use the
-ac
flag for SQL*Plus applications.
The
-ac
flag uses the standard
Dynamic
mode for session state, and disables at
COMMIT.
Static
mode is available only for static applications.
• Use the -ac flag, as follows: sqlplus –ac user/password@ACservice
Using Application Continuity for Planned Maintenance
For planned maintenance, the recommended approach is to drain requests from
Oracle connection pools in combination with Application Continuity for those
6-32 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage requests that do not complete. Instances do need to be stopped to switch over to the patched software.
This has the least impact when there is minimal recovery to complete.
To use Application Continuity for planned maintenance:
1.
Use any FAN-aware pool, such as OCI, UCP, WebLogic Server, or ODP.NET
Managed and Unmanaged Drivers.
The FAN planned event drains at request boundaries.
Note:
ODP.NET Managed Driver does not support Application Continuity.
2.
3.
4.
Use the srvctl relocate service
command to relocate the service from the instance without disrupting the sessions (do not use the
-force
parameter), or, for a uniform service, use the srvctl stop service
command on the instance
(again, do not use the
-force
parameter).
• For Oracle RAC One Node, use the srvctl relocate database command with the
-force
parameter.
The FAN planned event clears the idle sessions immediately and marks the active sessions to be released at check-in (end of request). This drains the sessions from the instance without disrupting work.
If not all sessions have checked in and the time to stop the instance has been reached, then stop the instance (abort).
For Application Continuity-enabled pools (UCP, WebLogic, Tuxedo, ODP.NET, and OCI), and any Java pool that adds beginRequest
/ endRequest
,
Application Continuity attempts to recover those remaining sessions.
Restart the instance and service.
Runtime load balancing, when enabled, balances the sessions back to the restored instance at the next request boundaries.
Running Without Application Continuity
Sometimes Application Continuity is not in effect, through deliberate choice, error, or oversight.
Application Continuity is not in effect when it has not been started or when it has been disabled. If it has been disabled, it remains so through to the endRequest
call.
Application Continuity is not started when the service property
FAILOVER_TYPE does not have the value set to
TRANSACTION
. For planned maintenance, set the
FAILOVER_TYPE
value to
TRANSACTION
, beforehand; the setting applies to new connections, and existing connections retain their original service value.
Application Continuity is disabled for the current request when any of the following occurs:
• The application runs a statement that is restricted for Application Continuity (for example,
ALTER SYSTEM
).
• Application Continuity is explicitly disabled using disableReplay
.
• A
COMMIT
statement is issued when the service parameter session_state_consistency
is set to
Dynamic
(the default).
Ensuring Application Continuity 6-33
Application Continuity Operation and Usage
• An endRequest
statement is issued until the next beginRequest
is issued.
• The session is terminated or disconnected and the
NOREPLAY
keyword is specified.
Related Topics:
Disabling Replay in Application Continuity
By default, replay occurs following a recoverable error.
Terminating or Disconnecting a Session Without Replay
Disabling Replay in Application Continuity
By default, replay occurs following a recoverable error.
If the application has requests that the application does not want repeated, the application can take a connection to a service that does not have Application
Continuity enabled, or can explicitly call an API to disable replay for those requests.
For example, if the application uses
UTL_SMTP
and does not want messages repeated,
use a connection to a different service, or use the disableReplay
API on Java, or
OCIRequestDisableReplay
API for OCI. All other requests continue to be replayed.
For applications with external actions (for example, autonomous transactions or using
UTL_HTTP
to issue an SOA call), Application Continuity remains transparent if the application's correctness is preserved when these external actions are replayed after a failure.
The following rules are generic. They apply to all applications that replay work, including Application Continuity, and TAF (release 12.2 and after).
•
•
Application Synchronizes Independent Sessions
•
Application Uses Time at the Middle Tier in the Execution Logic
•
Application Assumes that ROWIds Do Not Change
•
Application Assumes that Location Values Do Not Change
Related Topics:
Potential Side Effects of Application Continuity
When a session is rebuilt, all states are rebuilt, including rerunning statements that leave side effects.
Restrictions and Other Considerations for Application Continuity
Be aware of these restrictions and considerations when using
Application Continuity.
Application Calls Autonomous Transactions, External PL/SQL, or Java Actions that Should Not Be
Repeated
Autonomous transactions, external PL/SQL calls, and Java callouts can have side effects that are separate from the main transaction, and these side effects are replayed unless you specify otherwise.
6-34 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Examples of side effects separate from the main transaction include writing to an external table, sending email, forking sessions out of PL/SQL (including calls to
UTL_HTTP, UTL_URL, UTL_FILE, UTL_FILE_TRANSFER, UTL_SMPT, UTL_TCP,
UTL_MAIL, DBMS_PIPE, or DBMS_ALERT) or Java (including executing a shell script in the form Process proc = rt.exec(command);), transferring files, and accessing external
URLs. Actions such as these leave persistent side effects. PL/SQL messaging and Java callouts can leave persistent results behind. For example, if a user walks away part way through some work without committing and the session times out or the user issues Ctrl+C, the foreground or a component fails; the main transaction rolls back while the side effects may have been applied. (For more information about side effects,
see Potential Side Effects of Application Continuity
.)
Application developers decide whether to allow replay for external actions. Examples include using
UTL_HTTP
to issue an SOA call, or
UTL_SMTP
to send a message, or
UTL_URL
to access a website. If such external actions must not be replayed, use a connection without AC, or use one of the disable Replay APIs.
Application Synchronizes Independent Sessions
You must not configure an application for replay if the application synchronizes independent sessions using volatile entities that are held until
COMMIT
,
ROLLBACK
, or session loss. For example, the application might synchronize multiple sessions connected to several data sources that are otherwise inter-dependent using resources such as a database lock. This synchronization may be acceptable if the application is only serializing these sessions and understands that any session may fail. However, if the application assumes that a lock or any other volatile resource held by one data source implies exclusive access to data on the same or a separate data source from other connections, then this assumption may be invalidated when replaying.
During replay, the client driver is not aware that the sessions are dependent on one session holding a lock or other volatile resource. You can also use pipes, buffered queues, stored procedures taking a resource (such as a semaphore, device, or socket) to implement the synchronization that are lost by failures.
Application Uses Time at the Middle Tier in the Execution Logic
You must not configure an application for replay if the application uses the wall clock at the middle tier as part of the execution logic. The client driver does not repeat the middle-tier time logic, but uses the database calls that execute as part of this logic. For example, an application using middle-tier time might assume that a statement executed at Time T1 is not reexecuted at Time T2, unless the application explicitly does so.
Application Assumes that ROWIds Do Not Change
If an application caches ROWIDs, then access to these ROWIDs might be invalidated due to database changes. Although a ROWID uniquely identifies a row in a table, a
ROWID might change its value in the following situations:
• The underlying table is reorganized.
• An index is created on the table.
• The underlying table is partitioned.
• The underlying table is migrated.
• The underlying table is exported and imported using EXP/IMP/DUL.
Ensuring Application Continuity 6-35
Application Continuity Operation and Usage
• The underlying table is rebuilt using Golden Gate or Logical Standby or other replication technology.
• The database of the underlying table is flashed back or restored.
Oracle does not recommend, in general, that an application store ROWIDs for later use because the corresponding row might either not exist or contain completely different data. Note that ROWIDs do not prevent using Application Continuity. Replays can be rejected.
Application Assumes that Location Values Do Not Change
SYSCONTEXT
options comprise a location-independent set such as National Language
Support (NLS) settings,
ISDBA
,
CLIENT_IDENTIFIER
,
MODULE
, and
ACTION
, and a location-dependent set that uses physical locators. Typically, an application does not use the physical identifiers, except in testing environments. If physical locators are used in mainline code, then the replay finds the mismatch and rejects it. However, it is acceptable to use physical locators between requests (before beginRequest
) or in callbacks. A common issue is for QA to modify test applications to select
V
$INSTANCE
. As
V$INSTANCE
can change, only put this check in the callback or select the instance locally at the client and not from the database.
Example
select
sys_context('USERENV','DB_NAME')
,sys_context('USERENV','HOST')
,sys_context('USERENV','INSTANCE')
,sys_context('USERENV','IP_ADDRESS')
,sys_context('USERENV','ISDBA')
,sys_context('USERENV','SESSIONID')
,sys_context('USERENV','TERMINAL')
,sys_context('USERENV','SID') from dual;
Terminating or Disconnecting a Session Without Replay
If Application Continuity is configured and if a DBA terminates or disconnects a session by using the
ALTER SYSTEM KILL SESSION
or
ALTER SYSTEM
DISCONNECT SESSION
statement, then Application Continuity, by default attempts, to recover the session. However, if you do not want the session to be replayed, then use the
NOREPLAY
keyword, as follows: alter system kill session 'sid, serial#, @inst' noreplay; alter system disconnect session 'sid, serial#, @inst' noreplay
$ srvctl stop service -db orcl -instance orcl2 –drain_timeout 60 -stopoption immediate -force -noreplay
$ srvctl stop service -db orcl -node myode3 –noreplay -drain_timeout 60 -stopoption immediate -force
$ srvctl stop instance -node mynode3 -drain_timeout 60 -stopoption immediate -force – noreplay
To terminate all sessions running on the local instance (rather that only one session) and not have the sessions replayed, you can also use the
6-36 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
DBMS_SERVICE.DISCONNECT_SESSION
PL/SQL procedure and specify
NOREPLAY for the disconnect_option
parameter.
Related Topics:
Oracle Database SQL Language Reference
Oracle Database PL/SQL Packages and Types Reference
Mutable Functions and Application Continuity
When a request is replayed, the default and desired treatment of mutable objects can vary.
A mutable function is a nondeterministic function that can obtain a new value every time it is called. An example of a mutable function is a call to the
SYSTIMESTAMP function. Client applications using Application Continuity can determine whether to keep the original value for mutable functions if the request is replayed.
Support for keeping mutable fucntion values is currently provided for
SYSDATE
,
SYSTIMESTAMP
,
SYS_GUID
, and
sequence.NEXTVAL
. If the original values are not kept and if different values for these mutable objects are returned to the client, then replay is rejected because the client observes different results. If the application can use original values, then configure mutable functions using the
KEEP
clause for owned sequences and
GRANT KEEP
for other users. (Most applications need sequence values to be kept at replay, for bind variable consistency.)
Note:
Keeping
SYS_GUID
values is supported only for serial execution plans. When parallel query is used, Application Continuity is not able to restore original values for
SYS_GUID
.
shows examples of the treatment of mutable functions by products during replay. (Actual implementation depends on specific products and releases.)
Table 6-4 Example Treatment of Mutable Objects by Products During Replay
Mutable Function
SYSDATE
,
SYSTIMESTAMP
Sequence
NEXTVAL
and
CURRVAL
Product 1
Original
Original
Product 2
Original
Original
Product 3
Current
(Not applicable)
SYS_GUID
Original (Not applicable) (Not applicable)
To allow Application Continuity to keep and use original function results at replay:
• The database user running the application might have the
KEEP DATE TIME
and
KEEP SYSGUID
privileges granted, and the
KEEP SEQUENCE
object privilege on each sequence whose value is to be kept. For example: grant KEEP DATE TIME to user2; grant KEEP SYSGUID to user2; grant KEEP SEQUENCE on sales.seq1 to user2;
Ensuring Application Continuity 6-37
Application Continuity Operation and Usage
Notes:
–
GRANT ALL ON object
does not include (that is, does not grant the access provided by) the
KEEP DATE TIME
and
KEEP SYSGUID privileges, and the
KEEP SEQUENCE
object privilege.
– Grant privileges related to mutable function support only to application users, and to each application user grant only the necessary privileges.
– Do not grant DBA privileges to database users running applications for which you want replay to be enabled.
• Sequences in the application can use the
KEEP
attribute, which keeps the original values of
sequence.NEXTVAL
for the sequence owner, so that the keys match during replay. Most applications need sequence values to be kept at replay. The following example sets the
KEEP
attribute for a sequence (in this case, one owned by the user executing the statement; for others, use
GRANT KEEP SEQUENCE
):
SQL> CREATE SEQUENCE my_seq KEEP;
SQL> -- Or, if the sequence already exists but without KEEP:
SQL> ALTER SEQUENCE my_seq KEEP;
Note:
Specifying
ALTER SEQUENCE
...
KEEP/NOKEEP
applies to the owner of the sequence. It does not affect other users (not the owner) that have the
KEEP
SEQUENCE
object privileges. If you want
NOKEEP
for all users, then be sure not to grant the
KEEP SEQUENCE
object privilege to these users (or to revoke it from each user if the privilege has been granted).
• To keep function results (for named functions) at replay, the DBA must grant
KEEP
privileges to the user invoking the function. This security restriction ensures that it is valid for replay to save and restore function results for code that is not owned by that user.
The following additional considerations apply to granting privileges on mutable functions:
• If a user has the
KEEP
privilege granted on mutable function values, then the objects inherit mutable access when the
SYS_GUID
,
SYSDATE
, and
SYSTIMESTAMP
functions are called.
• If the
KEEP
privilege is revoked on mutable values on a sequence object, then SQL or PL/SQL blocks using that object do not allow mutable collection or application for that sequence.
• If granted privileges are revoked between runtime and failover, then the mutable values that are collected are not applied for replay.
• If new privileges are granted between runtime and failover, then mutable values are not collected and these values are not applied for replay.
Related Topics:
Oracle Database SQL Language Reference
6-38 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Oracle Database SQL Language Reference
Administering Mutable Values
To keep function results at replay, you must grant
KEEP
privileges to the user invoking the function.
Grant and Revoke Interface
To grant and revoke permission to keep
SYS_GUID
:
GRANT [KEEP DATE_TIME | KEEP SYS_GUID]...[to USER]
REVOKE [KEEP DATE_TIME | KEEP SYS_GUID]...[from USER]
For example, for possible Oracle E-Business Suite usage with original dates:
GRANT KEEP DATE_TIME, KEEP SYS_GUID to [custom user];
GRANT KEEP DATE_TIME, KEEP SYS_GUID to [apps user];
Granting Permission to Keep Mutables for Oracle Sequences
To grant permission to the owner of the sequence:
CREATE SEQUENCE [sequence object] [KEEP|NOKEEP];
ALTER SEQUENCE [sequence object] [KEEP|NOKEEP];
The preceding commands keep the original values of sequence.nextval
for replaying so that keys match.
To grant and revoke permission for others using the sequence:
GRANT KEEP SEQUENCES...[to USER] on [sequence object];
REVOKE KEEP SEQUENCES...[from USER] on [sequence object];
For example, for possible Oracle E-Business Suite usage with original sequence values:
GRANT KEEP SEQUENCES to [apps user] on [sequence object];
GRANT KEEP SEQUENCES to [custom user] on [sequence object];
Rules for Grants on Mutables
• If you grant all on an object for a user, then mutables are excluded. Mutables require explicit grants. Oracle does not support granting mutables to the users supplied or created by Oracle Database, such as SYS, AUDSYS, GSMUSER, and
SYSTEM.
• The DBA role includes mutable permission.
• If a user has mutables granted, then the objects inherit mutable access when the mutable functions are called (in
SYS_GUID
,
SYSDATE
and
SYSTIMESTAMP
).
• If keeping mutables on a sequence object is revoked, then SQL or PL/SQL commands using that object does not allow mutable collection or application for that sequence.
• If grants are revoked between run time and failover, then the mutables that were collected are not applied.
• If grants are granted between run time and failover, then mutables are not collected and so none are applied.
Ensuring Application Continuity 6-39
Application Continuity Operation and Usage
Session State Consistency
Session state consistency describes how non-transactional state is changed during a request.
Examples of session state are NLS settings, optimizer preferences, event settings,
PL/SQL global variables, temporary tables, advanced queues, LOBs, and result cache.
If non-transactional values change in committed transactions, then use the default value,
Dynamic
( session_state_consistency
is a service level attribute, the default value of which is
Dynamic
).
Using
Dynamic
mode, after a
COMMIT
has executed, if the state was changed in that transaction, then it is not possible to replay the transaction to reestablish that state if the session is lost. Applications can be categorized depending on whether the session state after the initial setup is static or dynamic, and hence whether it is correct to continue past a
COMMIT
operation.
Dynamic
mode is appropriate for almost all applications. If you are unsure, then use
Dynamic
mode. If your customers or users can modify your application, then you must use
Dynamic
mode.
This section includes the following topics:
•
Dynamic Session State Consistency
•
Static Session State Consistency
Dynamic Session State Consistency
A session has dynamic state if the session state values are not fully restored by
FAILOVER_RESTORE, or by adding the initialization callback.
Once the first transaction completes, failover is internally disabled until the next request starts. In
Dynamic
session state consistency mode, state changes occur during the request and replay is enabled at the beginning of the next request.
Set the session state consistency mode to
Dynamic
if the nontransactional session state changes while transactions are executing. Examples of nontransactional session state that can change at runtime are
ALTER SESSION
, PL/SQL global variables,
SYS_CONTEXT
, and temporary table contents. If the application changes nontransactional state inside transactions and commits, this state cannot be replayed and the state setting must be
Dynamic
. When using
Dynamic
mode for Application
Continuity, replay is disabled at
COMMIT
until the next request begins.
Dynamic
is the default value.
The nontransactional session state (NTSS) changes during a request when the session state consistency mode is
Dynamic
.
Replay (that is, Application Continuity) is enabled at the beginRequest
call, and is disabled on a
COMMIT
, an endRequest
call, or a restricted call. Following is the step logic for three application scenarios:
• No transaction
• A transaction with
COMMIT
as the last statement
• A transaction with an embedded
COMMIT
statement
For the request with no transaction, the logical steps are as follows:
6-40 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
1.
2.
3.
4.
Check out.
Begin request and enable replay.
Issue one or more
SELECT
statements and perhaps other PL/SQL statements.
Other actions.
5.
1.
Check in.
6.
End request and disable replay.
Replay is disabled at endRequest
, at a restricted call, and for an explicit disableReplay
or
OCIRequestDisableReplay
call.
For the request with a transaction with COMMIT as the last statement, the logical steps are as follows:
Check out.
2.
3.
4.
Begin request and enable replay.
Issue one or more
SELECT
statements and perhaps other PL/SQL statements.
The transaction begins.
5.
6.
Other actions.
Commit (which disables replay).
7.
1.
Check in.
8.
End request.
Replay is disabled at endRequest
, at a restricted call, and for an explicit disableReplay
or
OCIRequestDisableReplay
call.
For the request with a transaction with an embedded COMMIT statement, the logical steps are as follows:
Check out.
2.
3.
4.
5.
6.
7.
Begin request and enable replay.
Issue one or more
SELECT
statements and perhaps other PL/SQL statements.
The transaction begins.
Other actions.
Commit (which disables replay).
Other actions, during which Application Continuity is not covering the application.
8.
Check in.
9.
End request.
Replay is disabled at endRequest
, at a restricted call, and for an explicit disableReplay
or
OCIRequestDisableReplay
call.
Ensuring Application Continuity 6-41
Application Continuity Operation and Usage
Static Session State Consistency
Static
mode is used for long running stateless applications. Do not use
Static mode for applications that are not stateless.
Set the session state consistency mode to
Static
, only if all non-transactional state changes, such as NLS settings,
SYS_CONTEXT
, PL/SQL variables, and optimizer preferences, are set as part of the initialization once per request, and if this session state does not change during transactions. The settings can be established once per connection at connection establishment when using
FAILOVER_RESTORE=LEVEL1
, a callback, or labels, for example, or at each checkout from a pool.
When using
Static
mode for Application Continuity, transactional failover continues beyond the first transaction of a request. This is useful for applications that set beginRequest
once and run long processing operations such as batch jobs, and long reports.
Static mode is not supported for applications that use calls that change nontransactional state in transactions. Specific examples of such calls include:
• PL/SQL subprograms
•
SYS_CONTEXT
•
ALTER SESSION
Specify static mode with caution. Use static mode only when the application does not change the non-transactional session state inside transactions. Declaring the session state consistency mode as
Static
indicates that it is safe to continue beyond the first
COMMIT
in a request. Dynamic mode is appropriate for most applications. Do not use static mode if users or customers can modify or customize the application.
The non-transactional session state remaining constant (that is, not changing) during a request when the session state consistency mode is
Static
.
Replay (that is, Application Continuity) is enabled at the beginRequest
call, and is disabled on a restricted call, on a disableReplay
or
OCIRequestDisableReplay call, or on an endRequest
call.
Following is the step logic for three application scenarios:
• No transaction
• One or more transactions each ending with
COMMIT
as the last statement
• A transaction with a
COMMIT
statement followed by a transaction with a restricted call that disables Application Continuity
For the request with no transaction, the logical steps are as follows:
1.
Check out.
2.
3.
4.
5.
6.
Begin request and enable replay.
Issue one or more
SELECT
statements and perhaps other PL/SQL statements.
Other actions.
Check in.
End request and disable replay.
6-42 Oracle Real Application Clusters Administration and Deployment Guide
Application Continuity Operation and Usage
Replay is disabled at endRequest
, at a restricted call, and for an explicit disableReplay
or
OCIRequestDisableReplay
call.
For the request with one or more transactions (each with COMMIT as the last
statement)
, the logical steps are as follows:
1.
Check out.
2.
3.
4.
Begin request and enable replay.
Issue one or more
SELECT
statements and perhaps other PL/SQL statements.
The transaction begins.
5.
6.
7.
The transaction commits.
The transaction is purged.
(For each additional transaction, steps 4 through 6 occur.)
Other actions.
8.
Check in.
9.
End request.
Replay is disabled at endRequest
, at a restricted call, and for an explicit disableReplay
or
OCIRequestDisableReplay
call.
For the request with a transaction with a COMMIT followed by a transaction with a
restricted call
, the logical steps are as follows:
1.
2.
3.
4.
Check out.
Begin request and enable replay.
Issue one or more
SELECT
statements and perhaps other PL/SQL statements.
The transaction begins.
5.
6.
7.
The transaction commits.
The transaction is purged.
The second transaction begins.
8.
9.
The transaction makes a restricted call, which causes Application Continuity to be disabled.
The transaction is purged.
10.
Other actions
11.
Check in.
12.
End request.
Replay is disabled at endRequest
, at a restricted call, and for an explicit disableReplay
or
OCIRequestDisableReplay
call.
Ensuring Application Continuity 6-43
Potential Side Effects of Application Continuity
Related Topics:
Setting
FAILOVER_RESTORE
to
LEVEL1
automatically restores common state initial settings before replaying the request.
Potential Side Effects of Application Continuity
When a session is rebuilt, all states are rebuilt, including rerunning statements that leave side effects.
These side effects might be exactly what is required, such as writing a report or completing some auditing.
Application Continuity replays PL/SQL chronologically to restore database state. This serves to rebuild the session as if the user submission was delayed. Most applications want the full state rebuilt as if the submission was repeated, such as writing a report or completing some auditing. However, the actions that are replayed to build the state might include some for which you want to take action to accommodate or mitigate the effects of the replay. Some applications elect to disable replay for requests that contain calls that they do not want to repeat.
Examples of actions that create side effects include the following:
• Autonomous transactions (independent transactions that can be called from other transactions)
•
DBMS_ALERT
calls (email or other notifications)
•
DBMS_FILE_TRANSFER
calls (copying files)
•
DBMS_PIPE
and RPC calls (to external sources)
•
UTL_FILE
calls (writing text files)
•
UTL_HTTP
calls (making HTTP callouts)
•
UTL_MAIL
calls (sending email)
•
UTL_SMTP
calls (sending SMTP messages)
•
UTL_TCP
calls (sending TCP messages)
•
UTL_URL
calls (accessing URLs)
Related Topics:
Disabling Replay in Application Continuity
By default, replay occurs following a recoverable error.
Restrictions and Other Considerations for Application Continuity
Be aware of these restrictions and considerations when using Application Continuity.
• Application Continuity excludes :
– JDBC OCI driver (type 2)
– ODP.NET, Managed Driver
– OLE DB
6-44 Oracle Real Application Clusters Administration and Deployment Guide
Restrictions and Other Considerations for Application Continuity
– ODBC
• For applications using JDBC, there is no support for oracle.sql
deprecated concrete classes:
BLOB
,
CLOB
,
BFILE
,
OPAQUE
,
ARRAY
,
STRUCT
, or
ORADATA
.
• For streams arguments, replay is on a "best effort" basis. For example, if the application is using physical addresses, the address has gone with the outage and cannot be repositioned. JDBC stream setters (such as setBinaryStream
), for example, cause replay to be disabled.
• The replay target database must be in the same database cluster (Oracle RAC,
Oracle Data Guard, Oracle Active Data Guard, or Oracle Multitenant) as the source database.
To protect the integrity of business transactions, Application Continuity does not replay if the target is a different database or if it is the same database or same pluggable database but with data loss, such as one flashed back, recovered incompletely by media recovery, or opened by Oracle Data Guard earlier in time.
• For OCI and ODP.NET, in Oracle Database 12c release 2 (12.2.0.1), Application
Continuity on OCI driver excludes ADTs, advance queues, dynamic binds, and some LOB APIs. These exclusions do not apply to Java.
• If a statement cache at the application server level is enabled (for example, the
WebLogic or third-party application server statement cache), this must be disabled when the replay is used. Instead, configure the JDBC statement cache, which performs better because it is optimized for JDBC and Oracle and because it supports Application Continuity. Use oracle.jdbc.implicitstatementcachesize=nnn
.
• Starting with Oracle Database 12 release 2 (12.2), replay is supported for the XA data source for Java and ODP.NET, Unmanaged Driver. Replay supports local transactions. Replay silently disables when two-phase is used. This enables
Application Continuity to work very well with promotable XA and with applications using the XA data source and mostly not using XA.
• Replay is disabled if a request issues an
ALTER SYSTEM
or
ALTER DATABASE statement.
• Replay is disabled at a request level for
ALTER SESSION
statements that are deemed unsafe to rebuild the session. These include statements for setting support-level events, and disabling and enabling
COMMIT IN PROCEDURE
and
GUARD
.
However,
ALTER SESSION
statements at an application level are supported for replay. These include statements for globalization support (NLS) settings, stored and private outlines, setting the container (CDB/PDB), SQL trace, and PL/SQL warnings.
• Replay is not supported if you are using Oracle Active Data Guard with read/ write database links back to the primary database. This is a security restriction from Transaction Guard.
• Replay does not apply for failure of a parallel query call when this is a statementlevel failure. For example, replay would not occur after an
ORA-12805:parallel query server died unexpectedly
error for a call failure encountered during an instance or node failure or memory issue.
Ensuring Application Continuity 6-45
Transaction Guard for Improving Client Failover
• For Java only, replay does not support DRCP. Dedicated and Shared Servers are supported.
• The request uses 2PC XA. Starting with Oracle Database 12c release 2 (12.2),
Application Continuity is supported for promotable XA and using XA data sources, while XA is not in use.
Note:
If you are creating clones of databases by splitting disk images (for example,
BCVs) or by cloning so it is a "different" database to make a logical standby or logical copy that is not a physical or Oracle Active Data Guard database, then nid
must be used to change the DBID to differentiate the databases. For information about nid
program usage, see these My Oracle Support notes:
How to Change the DBID and the DBNAME by using NID
(Doc Id 224266.1) and
Changing DBNAME and DBID of Oracle RAC Database Using NID
(Doc Id
464922.1).
Related Topics:
Oracle Call Interface Programmer's Guide
Transaction Guard for Improving Client Failover
Transaction Guard prevents a transaction being replayed by Application Continuity from being applied more than once.
Failing to recognize that the last submission has committed, or that it shall commit sometime soon, or that the last submission has not run to completion, is a problem for applications. It can cause users who resubmit or applications that use their own replay to issue duplicate requests, repeating changes that are already committed to the database, and other forms of logical corruption. Transaction Guard can be used to solve this problem.
Application Continuity automatically enables and uses Transaction Guard, but you can also enable Transaction Guard independently. If the application has implemented an application-level replay, then it requires the application to be integrated with
Transaction Guard to provide idempotence.
In Oracle Database 12c, Transaction Guard provides a new, fully integrated tool for applications to use to achieve idempotence automatically and transparently, and in a manner that scales. Transaction Guard uses Logical Transaction ID (LTXID) to avoid submitting duplicate transactions. This is referred to as transaction idempotence. The
LTXID persists on commit and is reused following a rollback. During normal runtime, a LTXID is automatically held in the session at both the client and server for each database transaction. At commit, the LTXID is persisted as part of committing the transaction and the next LTXID to use is returned to the client.
Transaction Guard for XA Transactions
Transaction Guard also supports XA-based transactions, which are transactions that are an option for transaction managers, such as Oracle WebLogic Server, Oracle
Tuxedo, and MicroSoft Transaction Server (exposed to Oracle Database through
Oracle ODP.NET).
Transaction Guard support for XA transactions provides safe replay following recoverable outages for XA transactions on Oracle WebLogic Server. With the addition
6-46 Oracle Real Application Clusters Administration and Deployment Guide
Transaction Guard for Improving Client Failover of XA support, Oracle WebLogic Server can provide replay with idempotence enforced using Transaction Guard.
This section includes the following topics:
•
Transaction Guard Configuration Checklist
•
Configuring Services for Transaction Guard
•
Failing Over OCI Clients with TAF
Related Topics:
Oracle Database Development Guide
Oracle Database Development Guide
Oracle Database JDBC Developer’s Guide
Transaction Guard Configuration Checklist
Before configuring services for Transaction Guard, use the following configuration checklist:
• Grant permission to the application user who will call
GET_LTXID_OUTCOME
, as follows:
GRANT EXECUTE ON DBMS_APP_CONT to user_name;
• Locate and define the transaction history table for optimal performance.
The transaction history table (
LTXID_HIST
) is created, by default, in the SYSAUX tablespace when you create or upgrade an Oracle Database. New partitions are added when you add instances, using the storage of the last partition. If the location of transaction history table is not optimal for performance, then you can move it to another tablespace and create partitions there. For example, the following statement moves the transaction history table to a tablespace named
FastPace:
ALTER TABLE LTXID_TRANS move partition LTXID_TRANS_1 tablespace FastPace
storage ( initial 10G next 10G minextents 1 maxextents 121 );
• Set values for the
-commit_outcome
and
-retention_timeout
service parameters.
• If you are using Oracle RAC, Oracle Data Guard, or Oracle Active Data Guard, then Oracle recommends that you use FAN for fast notification of an outage.
Configuring Services for Transaction Guard
To configure services to use Transaction Guard, set the following service parameters:
•
-commit_outcome
: Set the
-commit_outcome
service parameter to
TRUE
. This service parameter determines whether the transaction
is accessible after the COMMIT has executed and an outage has occurred. While
Oracle Database has always made COMMIT durable, Transaction Guard makes
the outcome
of the COMMIT durable, and is used by applications to enforce the status of the last transaction executed before an outage.
Ensuring Application Continuity 6-47
Failing Over OCI Clients with TAF
•
-retention
: Use the
-retention
service parameter with
-commit_outcome
.
This service parameter determines the amount of time, in seconds, that the
COMMIT outcome is retained. Oracle recommends that most installations use the default value.
The following SRVCTL command configures a policy-managed service named sales for Transaction Guard:
$ srvctl add service -db crm -service sales -serverpool spool_1
-commit_outcome TRUE -retention 86400 -notification TRUE
The following SRVCTL command configures an administrator-managed service named sales
for Transaction Guard:
$ srvctl add service -db crm -service sales -preferred crm_1,crm_2
-available crm_3,crm_4 -commit_outcome TRUE -retention 86400
-notification TRUE
You can also modify an existing service to configure it for Transaction Guard by using the srvctl modify service
command.
Note:
Do not use the default database service, the service which has the name set to the value of db_name
or db_unique_name
. The default service is used for administrative purposes and does not have the same properties as usercreated services.
Related Topics:
Adds services to a database and assigns them to instances.
Modifies service configuration.
Application Continuity masks many recoverable database outages
(when replay is successful) from applications and users by restoring the database session: the full session, including all states, cursors, variables, and the last transaction if there is one.
Oracle Database JDBC Developer’s Guide
Oracle Call Interface Programmer's Guide
Failing Over OCI Clients with TAF
When Oracle Net Services establishes a connection to an instance, the connection remains open until the client closes the connection, the instance is shutdown, or a failure occurs.
If you configure transparent application failover (TAF) for the connection, then Oracle
Database replays the session at a surviving instance when an outage occurs.
TAF can restart a query after failover has completed but for other types of transactions, such as
INSERT
,
UPDATE
, or
DELETE
, the application must rollback the failed transaction and resubmit the transaction. You must also reexecute any session customizations, in other words,
ALTER SESSION
statements, after failover has
6-48 Oracle Real Application Clusters Administration and Deployment Guide
Failing Over OCI Clients with TAF occurred. However, with TAF, a connection is not moved during normal processing, even if the workload changes over time.
Services simplify the deployment of TAF. You can define a TAF policy for a service, and all connections using this service will automatically have TAF enabled. This does not require any client-side changes. The TAF setting on a service overrides any TAF setting in the client connection definition.
You can define a TAF policy for all users of a service by defining the
failovermethod
and
-failovertype
parameters. You can further define the TAF policy by setting the number of times that a failed session attempts to reconnect to the service and how long it should wait between reconnection attempts using the
failoverretry
and
-failoverdelay
parameters, respectively.
To define a TAF policy for a service, use SRVCTL as in the following example, where the service name is tafconn.example.com
and the database name is CRM:
$ srvctl modify service -db crm -service tafconn.example.com -failovermethod BASIC
-failovertype SELECT -failoverretry 10 -failoverdelay 30
OCI applications with TAF enabled should use FAN high availability events for fast connection failover.
TAF Supports Transaction Guard and FAILOVER_RESTORE
When you are using Transaction Guard, TAF manages the errors for the developers.
When you use both TAF and Transaction Guard, developers can use the TAF errors to roll back and safely resubmit or return uncommitted transactions (for TAF error codes
ORA-25402, ORA-25408, ORA-25405).
When you are using
FAILOVER_RESTORE
, TAF automatically restores common states, which avoids the need for a callback for most applications.
Related Topics:
Setting
FAILOVER_RESTORE
to
LEVEL1
automatically restores common state initial settings before replaying the request.
Ensuring Application Continuity 6-49
Failing Over OCI Clients with TAF
6-50 Administration and Deployment Guide
7
Configuring Recovery Manager and
Archiving
This chapter explains how to configure Recovery Manager (RMAN) for use in Oracle
Real Application Clusters (Oracle RAC) environments. This chapter also provides procedures for using for archiving in Oracle RAC environments and discusses online redo log and archived redo log considerations.
The topics in this chapter include:
•
Overview of Configuring RMAN for Oracle RAC
•
•
Configuring the RMAN Snapshot Control File Location
•
Configuring RMAN to Automatically Backup the Control File and SPFILE
•
Crosschecking on Multiple Oracle RAC Nodes
•
Configuring Channels for RMAN in Oracle RAC
•
Managing Archived Redo Logs Using RMAN in Oracle RAC
•
Archived Redo Log File Conventions in Oracle RAC
•
RMAN Archiving Configuration Scenarios
•
Monitoring the Archiver Processes
Overview of Configuring RMAN for Oracle RAC
RMAN enables you to back up, restore, and recover data files, control files, server parameter files (SPFILEs) and archived redo log files. RMAN is included with Oracle
Database and does not require separate installation. You can run RMAN from the command line or use RMAN in the Backup Manager in Oracle Enterprise Manager.
Archiving Mode in Oracle RAC
In order for redo log files to be archived, the Oracle RAC database must be in
ARCHIVELOG
mode.
You can run the
ALTER DATABASE
SQL statement to change the archiving mode in
Oracle RAC, because the database is mounted by the local instance but not open in any instances. You do not need to modify parameter settings to run this statement.
Configuring Recovery Manager and Archiving 7-1
Configuring the RMAN Snapshot Control File Location
Note:
• The
ARCHIVELOG
mode is set at the database level, not the instance level.
Either all instances archive or none do.
• You can also change the archive log mode by using the Recovery Settings page in the Maintenance tab of the Oracle Enterprise Manager Oracle
RAC Database Home Page.
Related Topics:
Oracle Database Administrator’s Guide
Configuring the RMAN Snapshot Control File Location
The snapshot control file is a copy of a database control file created in an operating system-specific location by RMAN.
RMAN creates the snapshot control file so that it has a consistent version of a control file to use when either resynchronizing the recovery catalog or backing up the control file.
You can specify a
or a raw device destination for the location of
your snapshot control file. This file is shared across all nodes in the
and must be accessible by all nodes in the cluster. Run the following RMAN command to determine the configured location of the snapshot control file:
SHOW SNAPSHOT CONTROLFILE NAME;
You can change the configured location of the snapshot control file. For example, on
Linux and UNIX systems you can specify the snapshot control file location as
$ORACLE_HOME/dbs/scf/snap_prod.cf
by entering the following at the RMAN prompt:
CONFIGURE SNAPSHOT CONTROLFILE NAME TO '$ORACLE_HOME/dbs/scf/snap_prod.cf';
This command sets the configuration for the location of the snapshot control file for
$ORACLE_HOME/dbs/scf
directory is shared by all nodes that perform backups.
The
CONFIGURE
command creates persistent settings across RMAN sessions.
Therefore, you do not need to run this command again unless you want to change the location of the snapshot control file.
To delete a snapshot control file you must first change the snapshot control file location, then delete the file at the older location, as follows:
CONFIGURE SNAPSHOT CONTROLFILE NAME TO 'new_name';
DELETE COPY OF CONTROLFILE;
Related Topics:
Oracle Database Backup and Recovery Reference
Configuring RMAN to Automatically Backup the Control File and SPFILE
If you set
CONFIGURE CONTROLFILE AUTOBACKUP
to
ON
, then RMAN automatically creates a control file and an SPFILE backup after you run the
BACKUP
or
COPY commands.
7-2 Oracle Real Application Clusters Administration and Deployment Guide
Crosschecking on Multiple Oracle RAC Nodes
RMAN can also automatically restore an SPFILE, if this is required to start an instance to perform recovery, because the default location for the SPFILE must be available to all nodes in your Oracle RAC database.
Note:
If you back up the control file using the SQL*Plus
ALTER DATABASE command, then you must also create the control file backup on a device shared by all nodes.
These features are important in disaster recovery because RMAN can restore the control file even without a recovery catalog. RMAN can restore an autobackup of the control file even after the loss of both the recovery catalog and the current control file.
You can change the default name that RMAN gives to this file with the
CONFIGURE
CONTROLFILE AUTOBACKUP FORMAT
command. Note that if you specify an absolute path name in this command, then this path must exist identically on all nodes that participate in backups.
RMAN performs the control file autobackup on the first allocated channel. Therefore, when you allocate multiple channels with different parameters, especially when you allocate a channel with the
CONNECT
command, determine which channel will perform the control file autobackup. Always allocate the channel for this node first.
Besides using the RMAN control file, you can also use Oracle Enterprise Manager to use the RMAN features.
Related Topics:
Oracle Database Backup and Recovery User’s Guide
Crosschecking on Multiple Oracle RAC Nodes
When crosschecking on multiple nodes (and when operating RMAN in general), configure the cluster so that all backups can be accessed by every node, regardless of which node created the backup.
When the cluster is configured this way, you can allocate channels to any node in the cluster during restore or crosscheck operations.
If you cannot configure the cluster so that each node can access all backups, then during restore and crosscheck operations, you must allocate channels on multiple nodes by providing the
CONNECT
option to the
CONFIGURE CHANNEL
command, so that every backup can be accessed by at least one node. If some backups are not accessible during crosscheck because no channel was configured on the node that can access those backups, then those backups are marked
EXPIRED
in the RMAN repository after the crosscheck.
For example, you can use
CONFIGURE CHANNEL ... CONNECT
in an Oracle RAC configuration in which tape backups are created on various nodes in the cluster and each backup is only accessible on the node on which it is created.
Related Topics:
Configuring Channels to Use a Specific Node
Oracle Database Backup and Recovery User’s Guide
Configuring Recovery Manager and Archiving 7-3
Configuring Channels for RMAN in Oracle RAC
Configuring Channels for RMAN in Oracle RAC
This section describes how to configure channels for RMAN. You can configure channels to use automatic load balancing or you can specify specific channels for specific instances as described in the following topics:
•
Configuring Channels to Use Automatic Load Balancing
•
Configuring Channels to Use a Specific Node
Configuring Channels to Use Automatic Load Balancing
To configure channels to use automatic load balancing, use the following syntax:
CONFIGURE DEVICE TYPE [disk | sbt] PARALLELISM number_of_channels;
...
Where
number_of_channels
is the number of channels that you want to use for the operation. After you complete this one-time configuration, you can issue
BACKUP
or
RESTORE
commands.
Configuring Channels to Use a Specific Node
To configure one RMAN channel for each policy-managed Oracle RAC database instance, use the following syntax:
CONFIGURE CHANNEL DEVICE TYPE sbt CONNECT '@racinst_1'
CONFIGURE CHANNEL DEVICE TYPE sbt CONNECT '@racinst_2'
...
After this one-time configuration step, you can issue the
BACKUP
or
RESTORE commands.
Managing Archived Redo Logs Using RMAN in Oracle RAC
When a node generates an archived redo log, Oracle Database always records the file name of the log in the control file of the target database. If you are using a recovery catalog, then RMAN also records the archived redo log filenames in the recovery catalog when a resynchronization occurs.
The archived redo log naming scheme that you use is important because when a node writes to a log with a specific file name on its file system, the file must be readable by any node that must access this archived redo log. For example, if node1
archives a log to
/oracle/arc_dest/log_1_100_23452345.arc
, then node2
can back up this archived redo log only if it can read
/oracle/arc_dest/ log_1_100_23452345.arc
on its own file system.
The backup and recovery strategy that you choose depends on how you configure the archiving destinations for each node. Whether only one node or all nodes perform archived redo log backups, you must ensure that all archived redo logs are backed up.
If you use RMAN parallelism during recovery, then the node that performs recovery must have read access to all archived redo logs in your cluster.
Multiple nodes can restore archived logs in parallel. However, during recovery, only one node applies the archived logs. Therefore, the node that is performing the recovery must be able to access all of the archived logs that are needed for the recovery operation. By default, the database determines the optimum number of
7-4 Oracle Real Application Clusters Administration and Deployment Guide
Archived Redo Log File Conventions in Oracle RAC parallel threads to use during the recovery operation. You can use the
PARALLEL clause in the
RECOVER
command to change the number of parallel threads.
Guidelines and Considerations for Archived Redo Logs
The primary consideration is to ensure that all archived redo logs can be read from every node during recovery, and, if possible, during backups. During recovery, if the archived log destinations are visible from the node that performs the recovery, then
Oracle Database can successfully recover the archived log data.
Archived Redo Log File Conventions in Oracle RAC
For any archived redo log configuration, uniquely identify the archived redo logs with the
LOG_ARCHIVE_FORMAT
parameter.
The format of this parameter is operating system-specific and it can include text strings, one or more variables, and a file name extension.
Table 7-1 Archived Redo Log File Name Format Parameters
Parameter Description
%r
Resetlogs identifier, not padded
%R
%s
%S
Resetlogs identifier, left-zero-padded
Log sequence number, not padded
Log sequence number, left-zeropadded
%t
%T
Thread number, not padded
Thread number, left-zero-padded
Example
log_1_62_23452345 log_1_62_0023452345 log_251 log_0000000251 log_1 log_0001
All of the file name format parameters for the archive redo logs, in either upper or lowercase, are mandatory for Oracle RAC. These parameters enable Oracle Database to create unique names for archive logs across the incarnation. This requirement is in effect when the
COMPATIBLE
parameter is set to
10.0
or greater.
Use the
%R
or
%r
parameters to include the resetlogs
identifier to avoid overwriting the logs from a previous incarnation. If you do not specify a log format, then the default is operating system-specific and includes
%t
,
%s
, and
%r
.
As an example, if the instance associated with redo thread number 1 sets
LOG_ARCHIVE_FORMAT
to log_%t_%s_%r.arc
, then its archived redo log files are named: log_1_1000_23435343.arc
log_1_1001_23452345.arc
log_1_1002_23452345.arc
...
Related Topics:
Oracle Database Administrator’s Guide
Configuring Recovery Manager and Archiving 7-5
RMAN Archiving Configuration Scenarios
RMAN Archiving Configuration Scenarios
This section describes the archiving scenarios for an Oracle RAC database. The two configuration scenarios in this chapter describe a three-node UNIX cluster for an
Oracle RAC database. For both scenarios, the
LOG_ARCHIVE_FORMAT
that you specify for the instance performing recovery must be the same as the format that you specified for the instances that archived the redo log files.
This section includes the following topics:
•
Oracle Automatic Storage Management and Cluster File System Archiving
•
Noncluster File System Local Archiving Scheme
Oracle Automatic Storage Management and Cluster File System Archiving Scheme
The preferred configuration for Oracle RAC is to use Oracle Automatic Storage
Management (Oracle ASM) for a recovery area using a disk group for your recovery set that is different from the disk group used for your data files.
When you use Oracle ASM, it uses an Oracle Managed Files naming format.
Alternatively, you can use a cluster file system archiving scheme. If you use a cluster file system, then each node writes to a single location on the cluster file system when archiving the redo log files. Each node can read the archived redo log files of the other nodes. For example, as shown in
Figure 7-1 , if Node 1 archives a redo log file to
/ arc_dest/log_1_100_23452345.arc
on the cluster file system, then any other node in the cluster can also read this file.
Figure 7-1 Cluster File System Archiving Scheme
Note:
The archive log naming format in this example is only for a cluster file system example.
7-6 Oracle Real Application Clusters Administration and Deployment Guide
RMAN Archiving Configuration Scenarios
If you do not use a cluster file system, then the archived redo log files cannot be on raw devices. This is because raw devices do not enable sequential writing of consecutive archive log files.
Related Topics:
Oracle Database Backup and Recovery User’s Guide
Advantages of the Cluster File System Archiving Scheme
The advantage of this scheme is that none of the nodes uses the network to archive logs. Because the file name written by a node can be read by any node in the cluster,
RMAN can back up all logs from any node in the cluster. Backup and restore scripts are simplified because each node has access to all archived redo logs.
Initialization Parameter Settings for the Cluster File System Archiving Scheme
In the cluster file system scheme, each node archives to a directory that is identified with the same name on all instances within the cluster database (
/arc_dest
, in the following example). To configure this directory, set values for the
LOG_ARCH_DEST_1 parameter, as shown in the following example:
*.LOG_ARCHIVE_DEST_1="LOCATION=/arc_dest"
The following list shows archived redo log entry examples that would appear in the
RMAN catalog or in the control file based on the previous example. Note that any node can archive logs using any of the threads:
/arc_dest/log_1_999_23452345.arc
/arc_dest/log_1_1000_23435343.arc
/arc_dest/log_1_1001_23452345.arc <- thread 1 archived in node3
/arc_dest/log_3_1563_23452345.arc <- thread 3 archived in node2
/arc_dest/log_2_753_23452345.arc <- thread 2 archived in node1
/arc_dest/log_2_754_23452345.arc
/arc_dest/log_3_1564_23452345.arc
Location of Archived Logs for the Cluster File System Archiving Scheme
Because the file system is shared and because each node is writing its archived redo logs to the
/arc_dest
directory in the cluster file system, each node can read the logs written by itself and any other node.
Noncluster File System Local Archiving Scheme
When archiving locally to a noncluster file system, each node archives to a uniquely named local directory. If recovery is required, then you can configure the recovery node so that it can access directories on the other nodes remotely. For example, use
NFS on Linux and UNIX computers, or mapped drives on Windows systems.
Therefore, each node writes only to a local destination, but each node can also read archived redo log files in remote directories on the other nodes.
Considerations for Using Noncluster File System Local Archiving
If you use noncluster file system local archiving for media recovery, then you must configure the node that is performing recovery for remote access to the other nodes so that it can read the archived redo log files in the archive directories on the other nodes.
In addition, if you are performing recovery and you do not have all of the available archive logs, then you must perform an incomplete recovery up to the first missing archived redo log sequence number. You do not have to use a specific configuration
Configuring Recovery Manager and Archiving 7-7
RMAN Archiving Configuration Scenarios for this scheme. However, to distribute the backup processing onto multiple nodes, the easiest method is to configure channels as described in the backup scenarios in
"Managing Backup and Recovery".
Note:
Because different file systems are used in a noncluster case, the archive log directories must be unique on each node. For example,
/arc_dest_1
is only available on node1
,
/arc_dest_2
is only directly mounted on node2
, and so on.
Then node1
mounts
/arc_dest_2
from node2
and
/arc_dest_3
from node3
through NFS.
Related Topics:
Initialization Parameter Settings for Noncluster File System Local Archiving
You can set the archiving destination values as follows in the initialization parameter file for either policy-managed or administrator-managed databases.
Set the
SID.LOG_ARCH_DEST
parameter for each instance using the SID designator, as shown in the following example: sid1.LOG_ARCHIVE_DEST_1="LOCATION=/arc_dest_1" sid2.LOG_ARCHIVE_DEST_1="LOCATION=/arc_dest_2" sid3.LOG_ARCHIVE_DEST_1="LOCATION=/arc_dest_3"
For policy-managed databases, manually create a node and instance binding to ensure that sid1
always runs on the same node, as follows:
$ srvctl modify database -d mydb -n node1 -i sid1
$ srvctl modify database -d mydb -n node2 -i sid2
$ srvctl modify database -d mydb -n node3 -i sid3
The following list shows the possible archived redo log entries in the database control file. Note that any node can read archived redo logs from any of the threads, which must happen in order for the database to recover after a failure.
/arc_dest_1/log_1_1000_23435343.arc
/arc_dest_2/log_1_1001_23452345.arc <- thread 1 archived in node2
/arc_dest_2/log_3_1563_23452345.arc <- thread 3 archived in node2
/arc_dest_1/log_2_753_23452345.arc <- thread 2 archived in node1
/arc_dest_2/log_2_754_23452345.arc
/arc_dest_3/log_3_1564_23452345.arc
Location of Archived Logs for Noncluster File System Local Archiving
As illustrated in Table 7-2 , each of three nodes has a directory containing the locally
archived redo logs. Additionally, if you mount directories on the other nodes remotely through NFS or mapped drives, then each node has two remote directories through which RMAN can read the archived redo log files that are archived by the remaining nodes.
7-8 Oracle Real Application Clusters Administration and Deployment Guide
RMAN Archiving Configuration Scenarios
Note:
The archive log destinations, similar to those shown in Table 7-2 , must be
different on each node so that if you mount the NFS directory on a different node, then it does not conflict with an existing archive log directory
1
2
2
1
1
2
3
3
3
Table 7-2 UNIX/NFS Location Log Examples, Noncluster File System Local
Archiving
Node Reads the archived redo log files in the directory
For logs archived by node
/arc_dest_1
1
/arc_dest_2
/arc_dest_3
/arc_dest_1
/arc_dest_2
/arc_dest_3
2 (through NFS)
3 (through NFS)
1 (through NFS)
2
3 (through NFS)
/arc_dest_1
/arc_dest_2
/arc_dest_3
1 (through NFS)
2 (through NFS)
3
File System Configuration for Noncluster File System Local Archiving
If you are performing recovery and a surviving instance must read all of the logs that are on disk but not yet backed up, then you should configure NFS as shown in
.
Table 7-3 UNIX/NFS Configuration for Shared Read Local Archiving Examples
3
3
2
2
3
1
1
Node Directory...
1
/arc_dest_1
2
/arc_dest_2
/arc_dest_3
/arc_dest_1
/arc_dest_2
/arc_dest_3
/arc_dest_1
/arc_dest_2
/arc_dest_3
Is configured...
Local read/write
NFS read
NFS read
NFS read
Local read/write
NFS read
NFS read
NFS read
Local read/write
And mounted on...
n/a
/arc_dest_2
/arc_dest_3
/arc_dest_1 n/a
/arc_dest_3
/arc_dest_1
/arc_dest_2 n/a
1
2 n/a
3 n/a
2
3
On node...
n/a
1
Configuring Recovery Manager and Archiving 7-9
Monitoring the Archiver Processes
Note:
Windows users can achieve the same results depicted in the examples in this section by using mapped drives.
Monitoring the Archiver Processes
After your RMAN configuration is operative in your Oracle RAC environment, use the
GV$ARCHIVE_PROCESSES
and
V$ARCHIVE_PROCESSES
views to determine the status of the archiver processes. Depending on whether you query the global or local views, these views display information for all database instances, or for only the instance to which you are connected.
Note:
If you use the kill
command to stop the archiver process, then the database instance will fail.
Related Topics:
Oracle Database Administrator’s Guide
Oracle Database Reference
7-10 Oracle Real Application Clusters Administration and Deployment Guide
8
Managing Backup and Recovery
This chapter explains instance recovery and how to use Recovery Manager (RMAN) to back up and restore Oracle Real Application Clusters (Oracle RAC) databases. This chapter also describes Oracle RAC instance recovery, parallel backup, recovery with
SQL*Plus, and using the Fast Recovery Area in Oracle RAC. The topics in this chapter include:
•
RMAN Backup Scenario for Noncluster File System Backups
•
RMAN Restore Scenarios for Oracle RAC
•
Instance Recovery in Oracle RAC
•
•
Parallel Recovery in Oracle RAC
•
Using a Fast Recovery Area in Oracle RAC
Note:
For restore and recovery in Oracle RAC environments, you do not have to configure the instance that performs the recovery to also be the sole instance that restores all of the data files. In Oracle RAC, data files are accessible from
, so any node can restore archived redo log files.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
See Also:
Oracle Clusterware Administration and Deployment Guide
for information about backing up and restoring the Oracle Clusterware components such as the
Oracle Cluster Registry (OCR) and the voting disk
RMAN Backup Scenario for Noncluster File System Backups
environment, each node can back up only to a locally
mounted noncluster file system directory. For example, node1
cannot access the archived redo log files on node2
or node3
unless you configure the network file system for remote access. If you configure a network file system file for backups, then each node backs up its archived redo logs to a local directory.
Managing Backup and Recovery 8-1
RMAN Restore Scenarios for Oracle RAC
RMAN Restore Scenarios for Oracle RAC
This section describes the following common RMAN restore scenarios:
•
Restoring Backups from a Cluster File System
•
Restoring Backups from a Noncluster File System
•
Using RMAN or Oracle Enterprise Manager to Restore the Server Parameter File
Note:
The restore and recovery procedures in a cluster file system scheme do not differ substantially from Oracle noncluster scenarios.
Restoring Backups from a Cluster File System
The scheme that this section describes assumes that you are using the "Oracle
Automatic Storage Management and Cluster File System Archiving Scheme". In this scheme, assume that node3
performed the backups to a cluster file system. If node3
is available for the restore and recovery operation, and if all of the archived logs have been backed up or are on disk, then run the following commands to perform complete recovery:
RESTORE DATABASE;
RECOVER DATABASE;
If node3
performed the backups but is unavailable, then configure a media management device for one of the remaining nodes and make the backup media from node3
available to this node.
Note:
If you configured RMAN as described in "Configuring Channels to Use
Automatic Load Balancing", then, to load balance the channels across nodes, note that channels cannot be load balanced before at least one instance has successfully opened the database. This means that the channels will not be load balanced across the nodes during a full database restore. To achieve load balancing of channels for
RESTORE
and
RECOVER
commands, you can temporarily reallocate channels by running commands similar to the following: run {
ALLOCATE CHANNEL DEVICE TYPE sbt C1 CONNECT '@racinst_1'
ALLOCATE CHANNEL DEVICE TYPE sbt C2 CONNECT '@racinst_2'
...
}
8-2 Oracle Real Application Clusters Administration and Deployment Guide
Instance Recovery in Oracle RAC
Related Topics:
Oracle Automatic Storage Management and Cluster File System Archiving
The preferred configuration for Oracle RAC is to use Oracle Automatic
Storage Management (Oracle ASM) for a recovery area using a disk group for your recovery set that is different from the disk group used for your data files.
Configuring Channels to Use Automatic Load Balancing
Restoring Backups from a Noncluster File System
The scheme that this section describes assumes that you are using the "Noncluster File
System Local Archiving Scheme". In this scheme, each node archives locally to a different directory. For example, node1
archives to
/arc_dest_1
, node2
archives to
/arc_dest_2
, and node3
archives to
/arc_dest_3
. You must configure a network file system file so that the recovery node can read the archiving directories on the remaining nodes.
If all nodes are available and if all archived redo logs have been backed up, then you can perform a complete restore and recovery by mounting the database and running the following commands from any node:
RESTORE DATABASE;
RECOVER DATABASE;
Because the network file system configuration enables each node read access to the redo log files on other nodes, then the recovery node can read and apply the archived redo logs located on the local and remote disks. No manual transfer of archived redo logs is required.
Related Topics:
Noncluster File System Local Archiving Scheme
Using RMAN or Oracle Enterprise Manager to Restore the Server Parameter File
(SPFILE)
RMAN can restore the server parameter file either to the default location or to a location that you specify.
You can also use Oracle Enterprise Manager to restore the SPFILE. From the Backup/
Recovery section of the Maintenance tab, click Perform Recovery. The Perform
Recovery link is context-sensitive and navigates you to the SPFILE restore only when the database is closed.
Instance Recovery in Oracle RAC
Instance failure occurs when software or hardware problems disable an instance. After instance failure, Oracle Database automatically uses the online redo logs to perform recovery as described in this section.
This section includes the following topics:
•
Single Node Failure in Oracle RAC
•
Multiple-Node Failures in Oracle RAC
Managing Backup and Recovery 8-3
Instance Recovery in Oracle RAC
•
Using RMAN to Create Backups in Oracle RAC
•
Node Affinity Awareness of Fast Connections
•
Deleting Archived Redo Logs after a Successful Backup
•
Autolocation for Backup and Restore Commands
Single Node Failure in Oracle RAC
Instance recovery in Oracle RAC does not include the recovery of applications that were running on the failed instance. Oracle Clusterware restarts the instance automatically.
Applications that were running on a node before it failed continue running by using failure recognition and recovery. This provides consistent and uninterrupted service if hardware or software fails. When one instance performs recovery for another instance, the surviving instance reads online redo logs generated by the failed instance and uses that information to ensure that committed transactions are recorded in the database.
Thus, data from committed transactions is not lost. The instance performing recovery rolls back transactions that were active at the time of the failure and releases resources used by those transactions.
Note:
All online redo logs must be accessible for instance recovery. Therefore, Oracle recommends that you mirror your online redo logs.
Multiple-Node Failures in Oracle RAC
When multiple node failures occur, if one instance survives, then Oracle RAC performs instance recovery for any other instances that fail. If all instances of an Oracle
RAC database fail, then Oracle Database automatically recovers the instances the next time one instance opens the database. The instance performing recovery can mount the database in either
or exclusive mode from any node of an Oracle
RAC database. This recovery procedure is the same for Oracle Database running in shared mode as it is for Oracle Database running in exclusive mode, except that one instance performs instance recovery for all of the failed instances.
Using RMAN to Create Backups in Oracle RAC
Oracle Database provides RMAN for backing up and restoring the database.
RMAN enables you to back up, restore, and recover data files, control files, SPFILEs, and archived redo logs. RMAN is included with the Oracle Database server and it is installed by default. You can run RMAN from the command line or you can use it from the Backup Manager in Oracle Enterprise Manager. In addition, RMAN is the recommended backup and recovery tool if you are using Oracle Automatic Storage
Management (Oracle ASM). The procedures for using RMAN in Oracle RAC environments do not differ substantially from those for Oracle noncluster environments.
Related Topics:
Oracle Database Backup and Recovery User’s Guide
8-4 Oracle Real Application Clusters Administration and Deployment Guide
Instance Recovery in Oracle RAC
Channel Connections to Cluster Instances with RMAN
Channel connections to the instances are determined using the connect string defined by channel configurations. For example, in the following configuration, three channels are allocated using dbauser/pwd@service_name
. If you configure the SQL Net service name with load balancing turned on, then the channels are allocated at a node as decided by the load balancing algorithm.
CONFIGURE DEVICE TYPE sbt PARALLELISM 3;
CONFIGURE DEFAULT DEVICE TYPE TO sbt;
CONFIGURE CHANNEL DEVICE TYPE SBT CONNECT 'dbauser/pwd@service_name'
However, if the service name used in the connect string is not for load balancing, then you can control at which instance the channels are allocated using separate connect strings for each channel configuration, as follows:
CONFIGURE DEVICE TYPE sbt PARALLELISM 3;
CONFIGURE CHANNEL 1.. CONNECT 'dbauser/pwd@mydb_1';
CONFIGURE CHANNEL 2.. CONNECT 'dbauser/pwd@mydb_2';
CONFIGURE CHANNEL 3.. CONNECT 'dbauser/pwd@mydb_3';
In the previous example, it is assumed that mydb_1
, mydb_2
and mydb_3
are
SQL*Net service names that connect to pre-defined nodes in your Oracle RAC environment. Alternatively, you can also use manually allocated channels to backup your database files. For example, the following command backs up the SPFILE, control file, data files and archived redo logs:
RUN
{
ALLOCATE CHANNEL CH1 CONNECT 'dbauser/pwd@mydb_1';
ALLOCATE CHANNEL CH2 CONNECT 'dbauser/pwd@mydb_2';
ALLOCATE CHANNEL CH3 CONNECT 'dbauser/pwd@mydb_3';
BACKUP DATABASE PLUS ARCHIVED LOG;
}
During a backup operation, if at least one channel allocated has access to the archived log, then RMAN automatically schedules the backup of the specific log on that channel. Because the control file, SPFILE, and data files are accessible by any channel, the backup operation of these files is distributed across the allocated channels.
For a local archiving scheme, there must be at least one channel allocated to all of the nodes that write to their local archived logs. For a cluster file system archiving scheme, if every node writes the archived logs in the same cluster file system, then the backup operation of the archived logs is distributed across the allocated channels.
During a backup, the instances to which the channels connect must be either all mounted or all open. For example, if the instance on node1
has the database mounted while the instances on node2
and node3
have the database open, then the backup fails.
See Also:
Oracle Database Backup and Recovery Reference
for more information about the
CONNECT
clause of the
CONFIGURE CHANNEL
statement
Managing Backup and Recovery 8-5
Instance Recovery in Oracle RAC
Related Topics:
Oracle Database Backup and Recovery Reference
Node Affinity Awareness of Fast Connections
In some cluster database configurations, some nodes of the cluster have faster access to certain data files than to other data files. RMAN automatically detects this situation, which is known as node affinity awareness. When deciding which channel to use to back up a particular data file, RMAN gives preference to the nodes with faster access to the data files that you want to back up. For example, if you have a three-node cluster, and if node1
has faster read/write access to data files 7, 8, and 9 than the other nodes, then node1
has greater node affinity to those files than node2
and node3
.
Deleting Archived Redo Logs after a Successful Backup
If you have configured the automatic channels as defined in section "Channel
Connections to Cluster Instances with RMAN", then you can use the following example to delete the archived logs that you backed up
n
times. The device type can be
DISK
or
SBT
:
DELETE ARCHIVELOG ALL BACKED UP n TIMES TO DEVICE TYPE device_type;
During a delete operation, if at least one channel allocated has access to the archived log, then RMAN automatically schedules the deletion of the specific log on that channel. For a local archiving scheme, there must be at least one channel allocated that can delete an archived log. For a cluster file system archiving scheme, if every node writes to the archived logs on the same cluster file system, then the archived log can be deleted by any allocated channel.
If you have not configured automatic channels, then you can manually allocate the maintenance channels as follows and delete the archived logs.
ALLOCATE CHANNEL FOR MAINTENANCE DEVICE TYPE DISK CONNECT 'SYS/oracle@node1';
ALLOCATE CHANNEL FOR MAINTENANCE DEVICE TYPE DISK CONNECT 'SYS/oracle@node2';
ALLOCATE CHANNEL FOR MAINTENANCE DEVICE TYPE DISK CONNECT 'SYS/oracle@node3';
DELETE ARCHIVELOG ALL BACKED UP n TIMES TO DEVICE TYPE device_type;
Related Topics:
Channel Connections to Cluster Instances with RMAN
Autolocation for Backup and Restore Commands
RMAN automatically performs autolocation of all files that it must back up or restore.
If you use the noncluster file system local archiving scheme, then a node can only read the archived redo logs that were generated by an instance on that node. RMAN never attempts to back up archived redo logs on a channel it cannot read.
During a restore operation, RMAN automatically performs the autolocation of backups. A channel connected to a specific node only attempts to restore files that were backed up to the node. For example, assume that log sequence 1001 is backed up to the drive attached to node1
, while log 1002 is backed up to the drive attached to node2
. If you then allocate channels that connect to each node, then the channel connected to node1
can restore log 1001 (but not 1002), and the channel connected to node2
can restore log 1002 (but not 1001).
8-6 Oracle Real Application Clusters Administration and Deployment Guide
Media Recovery in Oracle RAC
Media Recovery in Oracle RAC
Media recovery must be user-initiated through a client application, whereas instance recovery is automatically performed by the database. In these situations, use RMAN to restore backups of the data files and then recover the database. The procedures for
RMAN media recovery in Oracle RAC environments do not differ substantially from the media recovery procedures for noncluster environments.
The node that performs the recovery must be able to restore all of the required data files. That node must also be able to either read all of the required archived redo logs on disk or be able to restore them from backups.
When recovering a database with encrypted tablespaces (for example after a
SHUTDOWN ABORT
or a catastrophic error that brings down the database instance), you must open the Oracle Wallet after database mount and before you open the database, so the recovery process can decrypt data blocks and redo.
Parallel Recovery in Oracle RAC
Oracle Database automatically selects the optimum degree of parallelism for instance, crash, and media recovery.
Oracle Database applies archived redo logs using an optimal number of parallel processes based on the availability of CPUs. You can use parallel instance recovery and parallel media recovery in Oracle RAC databases as described under the following topics:
•
•
Related Topics:
Oracle Database Backup and Recovery User’s Guide
Parallel Recovery with RMAN
With RMAN's
RESTORE
and
RECOVER
commands, Oracle Database automatically makes parallel the following three stages of recovery:
Restoring Data Files
When restoring data files, the number of channels you allocate in the RMAN recover script effectively sets the parallelism that RMAN uses. For example, if you allocate five channels, you can have up to five parallel streams restoring data files.
Applying Incremental Backups
Similarly, when you are applying incremental backups, the number of channels you allocate determines the potential parallelism.
Applying Archived Redo Logs
With RMAN, the application of archived redo logs is performed in parallel. Oracle
Database automatically selects the optimum degree of parallelism based on available
CPU resources.
Managing Backup and Recovery 8-7
Using a Fast Recovery Area in Oracle RAC
Disabling Parallel Recovery
You can override parallel recovery using the procedures under the following topics:
•
Disabling Instance and Crash Recovery Parallelism
•
Disabling Media Recovery Parallelism
Disabling Instance and Crash Recovery Parallelism
To disable parallel instance and crash recovery on a system with multiple CPUs, set the
RECOVERY_PARALLELISM
parameter in the database initialization parameter file,
SPFILE, to
0
or
1
.
Disabling Media Recovery Parallelism
Use the
NOPARALLEL
clause of the RMAN
RECOVER
command or the
ALTER
DATABASE RECOVER
statement to force Oracle Database to use non-parallel media recovery.
Using a Fast Recovery Area in Oracle RAC
To use a fast recovery area in Oracle RAC, you must place it on an Oracle ASM disk group, on a Cluster File System, or on a shared directory that is configured through a network file system file for each Oracle RAC instance.
In other words, the fast recovery area must be shared among all of the instances of an
Oracle RAC database. In addition, set the parameter
DB_RECOVERY_FILE_DEST
to the same value on all instances.
Oracle Enterprise Manager enables you to set up a fast recovery area. To use this feature:
1.
2.
3.
4.
From the Cluster Database home page, click the Maintenance tab.
Under the Backup/Recovery options list, click Configure Recovery Settings.
Specify your requirements in the Fast Recovery Area section of the page.
Click Help on this page for more information.
Related Topics:
Oracle Database Backup and Recovery User’s Guide
8-8 Oracle Real Application Clusters Administration and Deployment Guide
9
Cloning Oracle RAC to Nodes in a New
Cluster
This chapter describes how to clone Oracle Real Application Clusters (Oracle RAC) database homes on Linux and UNIX systems to nodes in a new cluster.
This chapter describes a noninteractive cloning technique that you implement with scripts. The cloning techniques described in this chapter are best suited for performing multiple simultaneous cluster installations. Creating the scripts is a manual process and can be error prone. If you only have one cluster to install, then you should use the traditional automated and interactive installation methods, such as Oracle Universal
Installer, or the Provisioning Pack feature of Oracle Enterprise Manager.
Note:
Cloning is not a replacement for Oracle Enterprise Manager cloning that is a part of the Provisioning Pack. During Oracle Enterprise Manager cloning, the provisioning process interactively asks you the details about the Oracle home
(such as the location to which you want to deploy the clone, the name of the
Oracle Database home, a list of the nodes in the cluster, and so on).
The Provisioning Pack feature of Oracle Enterprise Manager Cloud Control provides a framework to make it easy for you to automate the provisioning of new nodes and clusters. For data centers with many Oracle RAC clusters, the investment in creating a cloning procedure to easily provision new clusters and new nodes to existing clusters is worth the effort.
This chapter includes the following topics:
•
Introduction to Cloning Oracle RAC
•
•
Deploying Oracle RAC Clone to Nodes in a Cluster
•
Locating and Viewing Log Files Generated During Cloning
Related Topics:
Using Cloning to Extend Oracle RAC to Nodes in the Same Cluster
Introduction to Cloning Oracle RAC
Cloning is the process of copying an existing Oracle RAC installation to a different location and updating the copied bits to work in the new environment. The changes made by one-off patches applied on the source Oracle home, would also be present
Cloning Oracle RAC to Nodes in a New Cluster 9-1
Preparing to Clone Oracle RAC after the clone operation. The source and the destination path (host to be cloned) need not be the same.
Some situations in which cloning is useful are:
• Cloning provides a way to prepare an Oracle home once and deploy it to many hosts simultaneously. You can complete the installation silently, as a noninteractive process. You do not need to use a graphical user interface (GUI) console and you can perform cloning from a Secure Shell (SSH) terminal session, if required.
• Cloning enables you to create an installation (copy of a production, test, or development installation) with all patches applied to it in a single step. Once you have performed the base installation and applied all patch sets and patches on the source system, the clone performs all of these individual steps as a single procedure. This is in contrast to going through the installation process to perform the separate steps to install, configure, and patch the installation on each node in the cluster.
• Installing Oracle RAC by cloning is a very quick process. For example, cloning an
Oracle home to a new cluster of more than two nodes requires a few minutes to install the Oracle base software, plus a few minutes more for each node
(approximately the amount of time it takes to run the root.sh
script).
The cloned installation behaves the same as the source installation. For example, the cloned Oracle home can be removed using Oracle Universal Installer or patched using
OPatch. You can also use the cloned Oracle home as the source for another cloning operation. You can create a cloned copy of a test, development, or production installation by using the command-line cloning scripts. The default cloning procedure is adequate for most usage cases. However, you can also customize various aspects of cloning, for example, to specify custom port assignments, or to preserve custom settings.
The cloning process works by copying all of the files from the source Oracle home to the destination Oracle home. Thus, any files used by the source instance that are located outside the source Oracle home's directory structure are not copied to the destination location.
The size of the binaries at the source and the destination may differ because these are relinked as part of the clone operation and the operating system patch levels may also differ between these two locations. Additionally, the number of files in the cloned home would increase because several files copied from the source, specifically those being instantiated, are backed up as part of the clone operation.
Preparing to Clone Oracle RAC
Use this overview to understand the procedures you use to clone Oracle RAC.
In the preparation phase, you create a copy of an Oracle home that you then use to perform the cloning procedure on one or more nodes. You also install Oracle
Clusterware.
Install Oracle RAC
Use the detailed instructions in Oracle Real Application Clusters Installation Guide for your platform for your platform to install the Oracle RAC software and patches:
1.
Install Oracle RAC and choose the Software only installation option.
9-2 Oracle Real Application Clusters Administration and Deployment Guide
Deploying Oracle RAC Clone to Nodes in a Cluster
2.
3.
Patch the release to the required level (for example, 12.1.0.n).
Apply one-off patches, if necessary.
Create a backup of the source home
Create a copy of the Oracle RAC home. Use this file to copy the Oracle RAC home to each node in the cluster.
When creating the backup (tar) file, the best practice is to include the release number in the name of the file. For example:
# cd /opt/oracle/product/12c/db_1
# tar –zcvf /pathname/db1120.tgz .
Install and start Oracle Clusterware
Before you can use cloning to create an Oracle RAC home, you must first install and start Oracle Clusterware on the node or nodes to which you want to copy a cloned
Oracle RAC home. In other words, you configure an Oracle RAC home that you cloned from a source cluster onto the nodes in a target cluster in the same order that you installed the Oracle Clusterware and Oracle RAC software components on the original nodes.
Related Topics:
Oracle Real Application Clusters Installation Guide
Deploying Oracle RAC Clone to Nodes in a Cluster
Oracle Clusterware Administration and Deployment Guide
Deploying Oracle RAC Clone to Nodes in a Cluster
After you complete the prerequisite tasks described in "Preparing to Clone Oracle
RAC", you can deploy cloned Oracle homes.
Deploy the Oracle RAC database home to a cluster, as follows:
1.
Perform any Oracle RAC preinstallation tasks, as described in your platformspecific Oracle RAC installation guide, to prepare the new cluster nodes, such things as:
2.
• Specify the kernel parameters.
• Ensure Oracle Clusterware is active.
• Ensure that Oracle ASM is active and that at least one Oracle ASM disk group exists and is mounted.
Deploy the Oracle RAC database software, as follows:
a.
Copy the clone of the Oracle home to all nodes. For example:
[root@node1 root]# mkdir -p /opt/oracle/product/12c/db
[root@node1 root]# cd /opt/oracle/product/12c/db
[root@node1 db]# tar –zxvf /path_name/db1120.tgz
Cloning Oracle RAC to Nodes in a New Cluster 9-3
Deploying Oracle RAC Clone to Nodes in a Cluster
b.
When providing the home location and
path_name
, the home location can be in the same directory path or in a different directory path from the source home that you used to create the tar.
If either the oracle
user or the oinstall
group, or both is different between the source and destination nodes, then change the ownership of the
Oracle Inventory files, as follows:
[root@node1]# chown -R oracle:oinstall /opt/oracle/product/12c/db
When you run the preceding command on the Oracle RAC home, it clears setuid
and setgid
information from the Oracle binary.
Note:
You can perform this step at the same time you perform Step
and Step
to run the clone.pl
and
$ORACLE_HOME/root.sh
scripts on each cluster node.
3.
Run the clone.pl
script on each node, which performs the main Oracle RAC cloning tasks, as follows:
a.
Supply the environment variables and cloning parameters in the start.sh
script, as described in Table 9-2 and Table 9-3 . Because the
clone.pl
script is sensitive to the parameters being passed to it, you must be accurate in your use of brackets, single quotation marks, and double quotation marks.
b.
Run the script as oracle
or the user that owns the Oracle RAC software.
The following table lists and describes the clone.pl
script parameters:
Table 9-1 clone.pl Script Parameters
Parameter
ORACLE_HOME=Oracl
e_home
ORACLE_BASE=ORACL
E_BASE
ORACLE_HOME_NAME=
Oracle_home_name
| defaultHomeName
ORACLE_HOME_USER=
Oracle_home_user
Description
The complete path to the Oracle home you want to clone. If you specify an invalid path, then the script exits. This parameter is required.
The complete path to the Oracle base you want to clone. If you specify an invalid path, then the script exits. This parameter is required.
The Oracle home name of the home you want to clone.
Optionally, you can specify the
-defaultHomeName
flag.
This parameter is optional.
OSDBA_GROUP=group
_name
OSOPER_GROUP=grou
p_name
OSASM_GROUP=group
_name
The OracleHomeUser for Windows services. This parameter is applicable to Windows only and is optional.
Specify the operating system group you want to use as the
OSDBA privileged group. This parameter is optional.
Specify the operating system group you want to use as the
OSOPER privileged group. This parameter is optional.
Specify the operating system group you want to use as the
OSASM privileged group. This parameter is optional.
9-4 Oracle Real Application Clusters Administration and Deployment Guide
Deploying Oracle RAC Clone to Nodes in a Cluster
Table 9-1 (Cont.) clone.pl Script Parameters
Parameter
OSBACKUPDBA_GROUP
=group_name
OSDGDBA_GROUP=gro
up_name
OSKMDBA_GROUP=gro
up_name
-debug
-help
Description
Specify the operating system group you want to use as the
OSBACKUPDBA privileged group. This parameter is optional.
Specify the operating system group you want to use as the
OSDGDBA privileged group. This parameter is optional.
Specify the operating system group you want to use as the
OSKMDBA privileged group. This parameter is optional.
Specify this option to run the clone.pl
script in debug mode
Specify this option to obtain help for the clone.pl
script.
The following example shows an excerpt from the start.sh
script that calls the clone.pl
script:
ORACLE_BASE=/opt/oracle
ORACLE_HOME=/opt/oracle/product/12c/db cd $ORACLE_HOME/clone
THISNODE='host_name'
E01=ORACLE_HOME=/opt/oracle/product/12c/db
E02=ORACLE_HOME_NAME=OraDBRAC
E03=ORACLE_BASE=/opt/oracle
C01="-O CLUSTER_NODES={node1,node2}"
C02="-O LOCAL_NODE=$THISNODE" perl $ORACLE_HOME/clone/bin/clone.pl $E01 $E02 $E03 $C01 $C02
The following table lists and describes the environment variables E01, E02, and
E03 that are shown in bold typeface in the preceding example:
Table 9-2 Environment Variables Passed to the clone.pl Script
Symbol Variable
E01
E02
E03
ORACLE_HOME
ORACLE_HOME_
NAME
ORACLE_BASE
Description
The location of the Oracle RAC database home. This directory location must exist and must be owned by the
Oracle operating system group: oinstall
.
The name of the Oracle home for the Oracle RAC database.
This is stored in the Oracle Inventory.
The location of the Oracle Base directory.
The following table lists and describes the cloning parameters C01 and C02, that are shown in bold typeface in the preceding example:
Table 9-3 Cloning Parameters Passed to the clone.pl Script.
Parameter Description Variabl e
C01
Name
Cluster Nodes
CLUSTER_NODE
S
Lists the nodes in the cluster.
Cloning Oracle RAC to Nodes in a New Cluster 9-5
Deploying Oracle RAC Clone to Nodes in a Cluster
4.
Table 9-3 (Cont.) Cloning Parameters Passed to the clone.pl Script.
Parameter Description Variabl e
C02
Name
Local Node
LOCAL_NODE
The name of the local node.
The following example shows an excerpt from the start.bat
script that the user must create that calls the clone.pl
script: set ORACLE_home=C:\oracle\product\12c\db1 cd %ORACLE_home%\clone\bin set THISNODE=%hostname% set E01=ORACLE_HOME=%ORACLE_home% set E02=ORACLE_HOME_NAME=OraDBRAC set E03=ORACLE_BASE=Oracle_Base set C01="CLUSTER_NODES={node1,node2}" set C02="-O LOCAL_NODE=%THISNODE%" perl clone.pl %E01% %E02% %E03% %C01% %C02%
Note:
This step applies to Linux and UNIX installations, only.
5.
Run the
$ORACLE_HOME/root.sh
as the root
operating system user as soon as the clone.pl
procedure completes on the node.
[root@node1 root]# /opt/oracle/product/12c/db/root.sh -silent
Note that you can run the script on each node simultaneously:
[root@node2 root]# /opt/oracle/product/12c/db/root.sh -silent
Ensure the script has completed on each node before proceeding to the next step.
Note:
You need only run DBCA on one node in the cluster to create Oracle RAC instances on all nodes.
This step shows how to run DBCA in silent mode and provide response file input to create the Oracle RAC instances.
The following example creates an Oracle RAC database named ERI on each node, creates database instances on each node, registers the instances in OCR, creates the database files in the Oracle ASM disk group called
DATA
, and creates sample schemas. It also sets the
SYS
,
SYSTEM
,
SYSMAN
and
DBSNMP
passwords to
password
, which is the password for each account:
[oracle@node1 oracle]$ export ORACLE_HOME=/opt/oracle/product/12c/db
[oracle@node1 oracle]$ cd $ORACLE_HOME/bin/
[oracle@node1 bin]$./dbca -silent -createDatabase -templateName
General_Purpose.dbc \
-gdbName ERI -sid ERI \
-sysPassword password -systemPassword password \
-sysmanPassword password -dbsnmpPassword password \
-emConfiguration LOCAL \
-storageType ASM -diskGroupName DATA \
9-6 Oracle Real Application Clusters Administration and Deployment Guide
Locating and Viewing Log Files Generated During Cloning
-datafileJarLocation $ORACLE_HOME/assistants/dbca/templates \
-nodelist node1,node2 -characterset WE8ISO8859P1 \
-obfuscatedPasswords false -sampleSchema true
Related Topics:
Use this overview to understand the procedures you use to clone Oracle
RAC.
Oracle Real Application Clusters Installation Guide
Oracle Database 2 Day DBA
Locating and Viewing Log Files Generated During Cloning
The cloning script runs multiple tools, each of which may generate its own log files.
After the clone.pl
script finishes running, you can view log files to obtain more information about the cloning process.
The following log files that are generated during cloning are the key log files of interest for diagnostic purposes:
•
Central_Inventory/logs/cloneActionstimestamp.log
Contains a detailed log of the actions that occur during the Oracle Universal
Installer part of the cloning.
•
Central_Inventory/logs/oraInstalltimestamp.err
Contains information about errors that occur when Oracle Universal Installer is running.
•
Central_Inventory/logs/oraInstalltimestamp.out
Contains other miscellaneous messages generated by Oracle Universal Installer.
•
$ORACLE_HOME/clone/logs/clonetimestamp.log
Contains a detailed log of the actions that occur before cloning and during the cloning operations.
•
$ORACLE_HOME/clone/logs/errortimestamp.log
Contains information about errors that occur before cloning and during cloning operations.
describes how to find the location of the Oracle inventory directory.
Table 9-4 Finding the Location of the Oracle Inventory Directory
Type of System...
All UNIX computers except Linux and IBM
AIX
IBM AIX and Linux
Windows
Location of the Oracle Inventory Directory
/var/opt/oracle/oraInst.loc
/etc/oraInst.loc
file.
C:\Program Files\Oracle\Inventory
Cloning Oracle RAC to Nodes in a New Cluster 9-7
Locating and Viewing Log Files Generated During Cloning
9-8 Administration and Deployment Guide
10
Using Cloning to Extend Oracle RAC to
Nodes in the Same Cluster
This chapter provides information about using cloning to extend Oracle Real
Application Clusters (Oracle RAC) to nodes in an existing cluster.
To add Oracle RAC to nodes in a new cluster, see
Cloning Oracle RAC to Nodes in a
.
This chapter contains the following topics:
•
About Adding Nodes Using Cloning in Oracle RAC Environments
•
Cloning Local Oracle Homes on Linux and UNIX Systems
•
Cloning Shared Oracle Homes on Linux and UNIX Systems
•
Cloning Oracle Homes on Windows Systems
Related Topics:
Cloning Oracle RAC to Nodes in a New Cluster
This chapter describes how to clone Oracle Real Application Clusters
(Oracle RAC) database homes on Linux and UNIX systems to nodes in a new cluster.
Introduction to Cloning Oracle RAC
Oracle Clusterware Administration and Deployment Guide
About Adding Nodes Using Cloning in Oracle RAC Environments
The cloning procedures assume that you have successfully installed and configured an
Oracle RAC environment to which you want to add nodes and instances. To add nodes to an Oracle RAC environment using cloning, first extend the Oracle
Clusterware configuration, then extend the Oracle Database software with Oracle
RAC, and then add the listeners and instances by running the Oracle assistants
The cloning script runs multiple tools, each of which may generate its own log files.
After the clone.pl
script finishes running, you can view log files to obtain more information about the cloning process. See "
Locating and Viewing Log Files Generated
" for more information.
Cloning Local Oracle Homes on Linux and UNIX Systems
Add nodes to existing Oracle RAC environments by cloning a local (non-shared)
Oracle home in Linux and UNIX system environments.
Complete the following steps to clone Oracle Database with Oracle RAC software:
Using Cloning to Extend Oracle RAC to Nodes in the Same Cluster 10-1
Cloning Shared Oracle Homes on Linux and UNIX Systems
1.
2.
3.
4.
Follow the steps in the "Preparing to Clone Oracle RAC" to create a copy of an
Oracle home that you then use to perform the cloning procedure on one or more nodes.
Use the tar
utility to create an archive of the Oracle home on the existing node and copy it to the new node. If the location of the Oracle home on the source node is
$ORACLE_HOME
, then you must use this same directory as the destination location on the new node.
On the new node, configure the environment variables
ORACLE_HOME
and
ORACLE_BASE
. Then go to the
$ORACLE_HOME/clone/bin
directory and run the following command, where
existing_node
is the name of the node that you are cloning,
new_node2
and
new_node3
are the names of the new nodes, and
Oracle_home_name
is the name of the Oracle home: perl clone.pl -O 'CLUSTER_NODES={existing_node,new_node2,new_node3}'
-O LOCAL_NODE=new_node2 ORACLE_BASE=$ORACLE_BASE ORACLE_HOME=$ORACLE_HOME
ORACLE_HOME_NAME=Oracle_home_name -O -noConfig
Run the following command to run the configuration assistants to configure
Oracle RAC on the new nodes:
$ORACLE_HOME/cfgtoollogs/configToolFailedCommands
5.
6.
This script contains all commands that failed, were skipped, or were canceled during the installation. You can use this script to run the database configuration assistants outside of Oracle Universal Installer. Note that before you run the script you should check the script to see if any passwords within it need to be updated.
Run the following command on the existing node from the
$ORACLE_HOME/oui/bin
directory to update the inventory in the Oracle
Database home with Oracle RAC, specified by
Oracle_home
, where
existing_node
is the name of the original node that you are cloning and
new_node2
and
new_node3
are the names of the new nodes:
./runInstaller -updateNodeList ORACLE_HOME=$ORACLE_HOME -O "CLUSTER_NODES=
{existing_node,new_node2,new_node3}"
On each new node, go to the
$ORACLE_HOME
directory and run the following command:
./root.sh
7.
From the node that you cloned, run Database Configuration Assistant (DBCA) to add Oracle RAC database instances on the new nodes.
Related Topics:
Use this overview to understand the procedures you use to clone Oracle
RAC.
Cloning Shared Oracle Homes on Linux and UNIX Systems
Add nodes to existing Oracle RAC environments by cloning a shared Oracle home in
Linux and UNIX system environments.
Complete the following steps to clone Oracle Database with Oracle RAC software:
10-2 Oracle Real Application Clusters Administration and Deployment Guide
Cloning Oracle Homes on Windows Systems
1.
2.
Follow the steps in the "Preparing to Clone Oracle RAC" to create a copy of an
Oracle home that you then use to perform the cloning procedure on one or more nodes.
On the new node, configure the environment variables
ORACLE_HOME
and
ORACLE_BASE
. Then go to the
$ORACLE_HOME/clone/bin
directory and run the following command, where
existing_node
is the name of the node that you are cloning,
new_node2
, and
new_node3
are the names of the new nodes,
Oracle_home_name
is the name of the Oracle home, and the
-cfs
option indicates the Oracle home is shared: perl clone.pl -O 'CLUSTER_NODES={existing_node,new_node2,new_node3}'
-O LOCAL_NODE=new_node2 ORACLE_BASE=$ORACLE_BASE ORACLE_HOME=$ORACLE_HOME
ORACLE_HOME_NAME=Oracle_home_name [-cfs]
Note:
In the preceding command:
• Use the
-cfs
option for a shared Oracle Database home with Oracle
RAC.
• The value for the
ORACLE_HOME_NAME
parameter must be that of the node you are cloning.
3.
4.
Run the following command on the existing node from the
$ORACLE_HOME/oui/bin
directory to update the inventory in the Oracle
Database home with Oracle RAC, specified by
Oracle_home
, where
existing_node
is the name of the original node that you are cloning and
new_node2
and
new_node3
are the names of the new nodes:
./runInstaller -updateNodeList ORACLE_HOME=$ORACLE_HOME "CLUSTER_NODES=
{existing_node,new_node2,new_node3}"
On each new node, go to the
$ORACLE_HOME
directory and run the following command:
5.
./root.sh
From the node that you cloned, run Database Configuration Assistant (DBCA) to add Oracle RAC database instances to the new nodes.
Related Topics:
Use this overview to understand the procedures you use to clone Oracle
RAC.
Cloning Oracle Homes on Windows Systems
Add nodes to existing Oracle RAC environments by cloning a shared or local Oracle home in Windows system environments.
Complete the following steps to clone Oracle Database with Oracle RAC software:
1.
If you have a local Oracle home, then use the ZIP utility to create an archive of the
Oracle Database home with Oracle RAC on the existing node and copy it to the new node. Otherwise, proceed to the next step.
Using Cloning to Extend Oracle RAC to Nodes in the Same Cluster 10-3
Cloning Oracle Homes on Windows Systems
2.
Extract the Oracle Database with Oracle RAC home files from the ZIP file on the new node in the same directory in which the Oracle Database home with Oracle
RAC resided on the existing node. For example, assume that the location of the destination Oracle RAC home on the new node is
%ORACLE_HOME%
.
On the new node, go to the
%ORACLE_HOME%\clone\bin
directory and run the following command, where
Oracle_Home
is the Oracle Database home,
Oracle_Home_Name
is the name of the Oracle Database home,
Oracle_Base
is the Oracle base directory,
user_name
is the name of the Oracle home user (a non-
Administrator user) for the Oracle home being cloned,
existing_node
is the name of the existing node, and
new_node
is the name of the new node: perl clone.pl ORACLE_HOME=Oracle_Home ORACLE_BASE=Oracle_Base
ORACLE_HOME_NAME=Oracle_Home_Name ORACLE_HOME_USER=user_name
-O 'CLUSTER_NODES={existing_node,new_node}'
-O LOCAL_NODE=new_node
If you have a shared Oracle Database home with Oracle RAC, then append the
cfs
option to the command to indicate that the Oracle home is shared, as shown in the following example: perl clone.pl ORACLE_HOME=Oracle_Home ORACLE_BASE=Oracle_Base
ORACLE_HOME_NAME=Oracle_Home_Name ORACLE_HOME_USER=user_name
-O 'CLUSTER_NODES={existing_node,new_node}' -O LOCAL_NODE=new_node
[-cfs -noConfig]
Note:
• The
ORACLE_HOME_USER
is required only if you are cloning a secured
Oracle home.
• Use the
-cfs
and
-noConfig
options for a shared Oracle Database home with Oracle RAC.
• The value for the
ORACLE_HOME_NAME
parameter must be that of the node you are cloning. To obtain the
ORACLE_HOME_NAME
, look in the registry on the node you cloning for the
ORACLE_HOME_NAME
parameter key under
HKEY_LOCAL_MACHINE\SOFTWARE\oracle
\KEY_OraCRs12c_home1
.
3.
4.
On the existing node, from the
%ORACLE_HOME%\oui\bin
directory run the following command to update the inventory in the Oracle Database home with
Oracle RAC, specified by
Oracle_home
, where
existing_node
is the name of the existing node, and
new_node
is the name of the new node: setup.exe -updateNodeList ORACLE_HOME=Oracle_home "CLUSTER_NODES=
{existing_node,new_node}" LOCAL_NODE=existing_node
From the node that you cloned, run DBCA to add Oracle RAC database instances to the new nodes.
10-4 Oracle Real Application Clusters Administration and Deployment Guide
11
Adding and Deleting Oracle RAC from
Nodes on Linux and UNIX Systems
Extend an existing Oracle Real Application Clusters (Oracle RAC) home to other nodes and instances in the cluster, and delete Oracle RAC from nodes and instances in the cluster.
If your goal is to clone an existing Oracle RAC home to create multiple new Oracle
RAC installations across the cluster, then use the cloning procedures that are described in "Cloning Oracle RAC to Nodes in a New Cluster".
The topics in this chapter include the following:
•
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
•
Deleting Oracle RAC from a Cluster Node
Note:
• Ensure that you have a current backup of Oracle Cluster Registry (OCR) before adding or deleting Oracle RAC by running the ocrconfig showbackup
command.
• The phrase "target node" as used in this chapter refers to the node to which you plan to extend the Oracle RAC environment.
Related Topics:
Cloning Oracle RAC to Nodes in a New Cluster
This chapter describes how to clone Oracle Real Application Clusters
(Oracle RAC) database homes on Linux and UNIX systems to nodes in a new cluster.
Oracle Database 2 Day + Real Application Clusters Guide
Adding and Deleting Oracle RAC from Nodes on Windows Systems
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
Before beginning this procedure, ensure that your existing nodes have the correct path to the
Grid_home
and that the
$ORACLE_HOME
environment variable is set to the
Oracle RAC home.
• If you are using a local (non-shared) Oracle home, then you must extend the
Oracle RAC database home that is on an existing node ( node1
in this procedure) to a target node ( node3
in this procedure).
Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems 11-1
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
Navigate to the
Oracle_home/addnode
directory on node1
and run the addnode.sh
script.
If you want to perform a silent installation, run the addnode.sh
script using the following syntax:
$ ./addnode.sh -silent "CLUSTER_NEW_NODES={node3}"
• If you have a shared Oracle home that is shared using Oracle Automatic Storage
Management Cluster File System (Oracle ACFS), then do the following to extend the Oracle database home to node3
:
1.
Start the Oracle ACFS resource on the new node by running the following command as root
from the
Grid_home/bin
directory:
# srvctl start filesystem -device volume_device [-node node_name]
Note:
Make sure the Oracle ACFS resources, including Oracle ACFS registry resource and Oracle ACFS file system resource where the Oracle home is located, are online on the newly added node.
2.
3.
Run the following command as the user that installed Oracle RAC from the
Oracle_home/oui/bin
directory on the node you are adding to add the
Oracle RAC database home:
$ ./runInstaller -attachHome ORACLE_HOME="ORACLE_HOME"
"CLUSTER_NODES={node3}"
LOCAL_NODE="node3" ORACLE_HOME_NAME="home_name" -cfs
Navigate to the
Oracle_home/addnode
directory on node1
and run the addnode.sh
script as the user that installed Oracle RAC using the following syntax:
$ ./addnode.sh -noCopy "CLUSTER_NEW_NODES={node3}"
Note:
Use the
-noCopy
option because the Oracle home on the destination node is already fully populated with software.
• If you have a shared Oracle home on a shared file system that is not Oracle ACFS, then you must first create a mount point for the Oracle RAC database home on the target node, mount and attach the Oracle RAC database home, and update the
Oracle Inventory, as follows:
1.
Run the srvctl config database -db db_name
command on an existing node in the cluster to obtain the mount point information.
2.
Run the following command as root
on node3
to create the mount point:
3.
# mkdir -p mount_point_path
Mount the file system that hosts the Oracle RAC database home.
11-2 Oracle Real Application Clusters Administration and Deployment Guide
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
4.
5.
Run the following command as the user that installed Oracle RAC from the
Oracle_home/oui/bin
directory on the node you are adding to add the
Oracle RAC database home:
$ ./runInstaller -attachHome ORACLE_HOME="ORACLE_HOME" "CLUSTER_NODES=
{local_node_name}" LOCAL_NODE="node_name" ORACLE_HOME_NAME="home_name"
Update the Oracle Inventory as the user that installed Oracle RAC, as follows:
$ ./runInstaller -updateNodeList ORACLE_HOME=mount_point_path
"CLUSTER_NODES=
{node_list}"
In the preceding command,
node_list
refers to a list of all nodes where the
Oracle RAC database home is installed, including the node you are adding.
Run the
Oracle_home/root.sh
script on node3
as root
.
Note:
Oracle recommends that you back up the OCR after you complete the node addition process.
You can now add an Oracle RAC database instance to the target node using either of the procedures in the following sections.
•
Adding Policy-Managed Oracle RAC Database Instances to Target Nodes
•
Adding Administrator-Managed Oracle RAC Database Instances to Target Nodes
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Adding Policy-Managed Oracle RAC Database Instances to Target Nodes
You must manually add undo and redo logs, unless you store your policy-managed database on Oracle Automatic Storage Management (Oracle ASM) and
is enabled.
If there is space in a server pool to add a node and the database has been started at least once, then Oracle Clusterware adds the Oracle RAC database instance to the newly added node and no further action is necessary.
Note:
The database must have been started at least once before you can add the database instance to the newly added node.
If there is no space in any server pool, then the newly added node moves into the Free server pool. Use the srvctl modify srvpool
command to increase the cardinality of a server pool to accommodate the newly added node, after which the node moves out of the Free server pool and into the modified server pool, and Oracle Clusterware adds the Oracle RAC database instance to the node.
Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems 11-3
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
Adding Administrator-Managed Oracle RAC Database Instances to Target Nodes
Note:
The procedures in this section only apply to administrator-managed databases. Policy-managed databases use nodes when the nodes are available in the database’s server pool.
You can use either Oracle Enterprise Manager or DBCA to add Oracle RAC database instances to the target nodes. To add a database instance to a target node with Oracle
Enterprise Manager, see the Oracle Database 2 Day + Real Application Clusters Guide for complete information.
This section describes using DBCA to add Oracle RAC database instances.
These tools guide you through the following tasks:
• Creating a new database instance on each target node
• Creating and configuring high availability components
• Creating the Oracle Net configuration for a non-default listener from the Oracle home
• Starting the new instance
• Creating and starting services if you entered services information on the Services
Configuration page
After adding the instances to the target nodes, you should perform any necessary service configuration procedures, as described in "Workload Management with
Dynamic Database Services".
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
Workload Management with Dynamic Database Services
Workload management includes load balancing, enabling clients for
Oracle Real Application Clusters (Oracle RAC), distributed transaction processing, and services.
Using DBCA in Interactive Mode to Add Database Instances to Target Nodes
To add a database instance to a target node with DBCA in interactive mode, perform the following steps:
1.
2.
Ensure that your existing nodes have the
$ORACLE_HOME
environment variable set to the Oracle RAC home.
Start DBCA by entering dbca
at the system prompt from the
Oracle_home/bin directory.
DBCA performs certain CVU checks while running. However, you can also run
CVU from the command line to perform various verifications.
DBCA displays the Welcome page for Oracle RAC. Click Help on any DBCA page for additional information.
11-4 Oracle Real Application Clusters Administration and Deployment Guide
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
3.
4.
5.
6.
7.
8.
9.
Select Instance Management, click Next, and DBCA displays the Instance
Management page.
Select Add Instance and click Next. DBCA displays the List of Cluster Databases page that shows the databases and their current status, such as
ACTIVE
or
INACTIVE
.
From the List of Cluster Databases page, select the active Oracle RAC database to which you want to add an instance. Click Next and DBCA displays the List of
Cluster Database Instances page showing the names of the existing instances for the Oracle RAC database that you selected.
Click Next to add a new instance and DBCA displays the Adding an Instance page.
On the Adding an Instance page, enter the instance name in the field at the top of this page if the instance name that DBCA provides does not match your existing instance naming scheme.
Review the information on the Summary dialog and click OK or click Cancel to end the instance addition operation. DBCA displays a progress dialog showing
DBCA performing the instance addition operation.
After you terminate your DBCA session, run the following command to verify the administrative privileges on the target node and obtain detailed information about these privileges where
node_list
consists of the names of the nodes on which you added database instances: cluvfy comp admprv -o db_config -d Oracle_home -n node_list [-verbose]
10.
Perform any necessary service configuration procedures, as described in
"Workload Management with Dynamic Database Services".
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Workload Management with Dynamic Database Services
Workload management includes load balancing, enabling clients for
Oracle Real Application Clusters (Oracle RAC), distributed transaction processing, and services.
Using DBCA in Silent Mode to Add Database Instances to Target Nodes
You can use DBCA in silent mode to add instances to nodes on which you have extended an Oracle Clusterware home and an Oracle Database home.
Before you run the dbca
command, ensure that you have set the
ORACLE_HOME environment variable correctly on the existing nodes. Run DBCA, supplying values for
the variables described in Table 11-1 , as follows:
dbca -silent -nodeList node_name -gdbName gdb_name
[-instanceName instance_name -sysDBAUserName sysdba -sysDBAPassword
password]
Table 11-1 Variables in the DBCA Silent Mode Syntax
Variable
node_name
Description
The node on which you want to add (or delete) the instance.
Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems 11-5
Deleting Oracle RAC from a Cluster Node
Table 11-1 (Cont.) Variables in the DBCA Silent Mode Syntax
Variable
gdb_name instance_name sysdba password
Description
Global database name.
Name of the instance. Provide an instance name only if you want to override the Oracle naming convention for Oracle RAC instance names.
Name of the Oracle user with
SYSDBA
privileges.
Password for the
SYSDBA
user.
Perform any necessary service configuration procedures, as described in "Workload
Management with Dynamic Database Services".
Related Topics:
Workload Management with Dynamic Database Services
Workload management includes load balancing, enabling clients for
Oracle Real Application Clusters (Oracle RAC), distributed transaction processing, and services.
Deleting Oracle RAC from a Cluster Node
To remove Oracle RAC from a cluster node, you must delete the database instance and the Oracle RAC software before removing the node from the cluster.
Note:
If there are no database instances on the node you want to delete, then proceed to "Removing Oracle RAC".
This section includes the following procedures to delete nodes from clusters in an
Oracle RAC environment:
•
Deleting Instances from Oracle RAC Databases
•
•
Deleting Nodes from the Cluster
Related Topics:
This procedure removes Oracle RAC software from the node you are deleting from the cluster and updates inventories on the remaining nodes.
Deleting Instances from Oracle RAC Databases
The procedures for deleting database instances are different for policy-managed and administrator-managed databases.
11-6 Oracle Real Application Clusters Administration and Deployment Guide
Deleting Oracle RAC from a Cluster Node
Deleting a policy-managed database instance involves reducing the number of servers in the server pool in which the database instance resides. Deleting an administratormanaged database instance involves using DBCA to delete the database instance.
Deleting Policy-Managed Databases
To delete a policy-managed database, reduce the number of servers in the server pool in which a database instance resides by relocating the server on which the database instance resides to another server pool. This effectively removes the instance without having to remove the Oracle RAC software from the node or the node from the cluster.
For example, you can delete a policy-managed database by running the following commands on any node in the cluster:
$ srvctl stop instance -db db_unique_name -node node_name
$ srvctl relocate server -servers "server_name_list" -serverpool Free
The first command stops the database instance on a particular node and the second command moves the node out of its current server pool and into the Free server pool.
Deleting Instances from Administrator-Managed Databases
Note:
Before deleting an instance from an Oracle RAC database using SRVCTL to do the following:
• If you have services configured, then relocate the services
• Modify the services so that each service can run on one of the remaining instances
• Ensure that the instance to be removed from an administrator-managed database is neither a preferred nor an available instance of any service
Related Topics:
This procedure removes Oracle RAC software from the node you are deleting from the cluster and updates inventories on the remaining nodes.
Administering Services with SRVCTL
When you create a service using SRVCTL, you must start the service with a separate SRVCTL command.
Using DBCA in Interactive Mode to Delete Instances from Nodes
The procedure in this section explains how to use DBCA in interactive mode to delete an instance from an Oracle RAC database.
Oracle Database 2 Day + Real Application Clusters Guide
Using DBCA in Interactive Mode to Delete Instances from Nodes
The procedure in this section explains how to use DBCA in interactive mode to delete an instance from an Oracle RAC database.
To delete an instance using DBCA in interactive mode, perform the following steps:
Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems 11-7
Deleting Oracle RAC from a Cluster Node
1.
2.
3.
4.
5.
6.
7.
Start DBCA.
Start DBCA on a node other than the node that hosts the instance that you want to delete. The database and the instance that you plan to delete should be running during this step.
On the DBCA Operations page, select Instance Management and click Next.
DBCA displays the Instance Management page.
On the DBCA Instance Management page, select the instance to be deleted, select
Delete Instance,
and click Next.
On the List of Cluster Databases page, select the Oracle RAC database from which to delete the instance, as follows:
a.
b.
On the List of Cluster Database Instances page, DBCA displays the instances that are associated with the Oracle RAC database that you selected and the status of each instance. Select the cluster database from which you will delete the instance.
Click OK on the Confirmation dialog to proceed to delete the instance.
DBCA displays a progress dialog showing that DBCA is deleting the instance.
During this operation, DBCA removes the instance and the instance's Oracle
Net configuration.
Click No and exit DBCA or click Yes to perform another operation. If you click Yes, then DBCA displays the Operations page.
Verify that the dropped instance's redo thread has been removed by using
SQL*Plus on an existing node to query the
GV$LOG
view. If the redo thread is not disabled, then disable the thread. For example:
SQL> ALTER DATABASE DISABLE THREAD 2;
Verify that the instance has been removed from OCR by running the following command, where
db_unique_name
is the database unique name for your Oracle
RAC database:
$ srvctl config database -db db_unique_name
If you are deleting more than one node, then repeat these steps to delete the instances from all the nodes that you are going to delete.
Using DBCA in Silent Mode to Delete Instances from Nodes
You can use DBCA in silent mode to delete a database instance from a node.
Run the following command, where the variables are the same as those shown in
Table 11-1 for the DBCA command to add an instance. Provide a node name only if
you are deleting an instance from a node other than the one on where DBCA is running as shown in the following example where
password
is the password: dbca -silent -deleteInstance [-nodeList node_name] -gdbName gdb_name
-instanceName instance_name [-sysDBAUserName sysdba -sysDBAPassword password]
At this point, you have accomplished the following:
• Deregistered the selected instance from its associated Oracle Net Services listeners
• Deleted the selected database instance from the instance's configured node
11-8 Oracle Real Application Clusters Administration and Deployment Guide
Deleting Oracle RAC from a Cluster Node
• Removed the Oracle Net configuration
• Deleted the Oracle Flexible Architecture directory structure from the instance's configured node.
Removing Oracle RAC
This procedure removes Oracle RAC software from the node you are deleting from the cluster and updates inventories on the remaining nodes.
1.
2.
If there is a listener in the Oracle RAC home on the node you are deleting, then you must disable and stop it before deleting the Oracle RAC software. Run the following commands on any node in the cluster, specifying the name of the listener and the name of the node you are deleting:
$ srvctl disable listener -l listener_name -n name_of_node_to_delete
$ srvctl stop listener -l listener_name -n name_of_node_to_delete
Deinstall the Oracle home—only if the Oracle home is not shared—from the node that you are deleting by running the following command from the
Oracle_home
\deinstall
directory: deinstall -local
Caution:
If the Oracle home is shared, then do not run this command because it will remove the shared software. Proceed to the next step, instead.
Deleting Nodes from the Cluster
After you delete the database instance and the Oracle RAC software, you can begin the process of deleting the node from the cluster. You accomplish this by running scripts on the node you want to delete to remove the Oracle Clusterware installation and then you run scripts on the remaining nodes to update the node list.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems 11-9
Deleting Oracle RAC from a Cluster Node
11-10 Administration and Deployment Guide
12
Adding and Deleting Oracle RAC from
Nodes on Windows Systems
This chapter describes how to extend an existing Oracle Real Application Clusters
(Oracle RAC) home to other nodes and instances in the cluster, and delete Oracle RAC from nodes and instances in the cluster. This chapter provides instructions for
Windows systems.
Note:
In this chapter, the entries for
Grid_home
refer to the full path name for the
Oracle Grid Infrastructure home, and the entries for
Oracle_home
refer to substitutes for environment variables for the Oracle home with Oracle RAC.
If your goal is to clone an existing Oracle RAC home to create multiple new Oracle
RAC installations across the cluster, then use the cloning procedures that are described in "Cloning Oracle RAC to Nodes in a New Cluster".
This chapter includes the following topics:
•
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
•
Deleting Oracle RAC from a Cluster Node
Note:
• Ensure that you have a current backup of Oracle Cluster Registry (OCR) before adding or deleting Oracle RAC by running the ocrconfig showbackup
command.
• For all of the add node and delete node procedures, temporary directories such as
%TEMP%
or
C:\Temp
should not be shared directories. If your temporary directories are shared, then set your temporary environment variable, such as
%TEMP%
, to a location on a local node. In addition, use a directory path that exists on all of the nodes.
Related Topics:
Cloning Oracle RAC to Nodes in a New Cluster
This chapter describes how to clone Oracle Real Application Clusters
(Oracle RAC) database homes on Linux and UNIX systems to nodes in a new cluster.
Oracle Database 2 Day + Real Application Clusters Guide
Adding and Deleting Oracle RAC from Nodes on Windows Systems 12-1
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
Before beginning this procedure, ensure that your existing nodes have the correct path to the
Grid_home
and that the
Oracle_home
environment variables are set correctly.
To add Oracle RAC database instances to nodes that already have Oracle Clusterware installed, you must extend the Oracle RAC home that is on an existing node ( node1
in this procedure) of the cluster to the target nodes.
1.
Navigate to the
Oracle_home\addnode
directory on node1
and run the addnode.bat
script using the following syntax, where node2
is the name of the node you are adding: addnode.bat "CLUSTER_NEW_NODES={node2}"
To run this command in silent mode: addNode.bat -silent "CLUSTER_NEW_NODES={node2}"
For the Oracle home directory you use, if an Oracle home user was specified when the Oracle Database software was installed, then OUI requires the password for the Oracle home user. OUI checks the wallet (stored in the OCR) for the user and extracts the password from there. If the user information is not contained in the wallet, then the addnode.bat
script generates an error unless you specify the
promptPasswd
flag on the command line.
2.
If you store your policy-managed database on Oracle Automatic Storage
Management (Oracle ASM),
space in a server pool for node2
, then crsd
adds the Oracle RAC database instance to node2
and no further action is necessary. If Oracle Managed Files is not enabled, then you must manually add undo and redo logs.
If there is no space in a server pool, then node2
moves into the Free server pool.
Use the srvctl modify srvpool
command to increase the cardinality of the server pool to accommodate node2
, after which time node2
moves out of the
Free server pool and into the modified server pool, and crsd
adds the Oracle
RAC database instance to node2
.
3.
If you have an administrator-managed database, then add a new instance on node2
If you have a shared Oracle home that is shared using Oracle Automatic Storage
Management Cluster File System (Oracle ACFS), then do the following to extend the
Oracle database home to node2
:
1.
Start the Oracle ACFS resource on the new node by running the following command as root
from the
Grid_home\bin
directory:
$ srvctl start filesystem -device volume_device_name [-node node_name]
Note:
Make sure the Oracle ACFS resources, including Oracle ACFS registry resource and Oracle ACFS file system resource where the Oracle home is located, are online on the newly added node.
12-2 Oracle Real Application Clusters Administration and Deployment Guide
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
2.
3.
Run the following command as the user that installed Oracle RAC from the
Oracle_home\oui\bin
directory on the node you are adding to add the Oracle
RAC database home: setup.exe -attachHome ORACLE_HOME="ORACLE_HOME" LOCAL_NODE="node2"
ORACLE_HOME_NAME="home_name" -cfs
Navigate to the
Oracle_home\addnode
directory on node1
and run the addnode.bat
script as the user that installed Oracle RAC using the following syntax: addnode.bat -noCopy "CLUSTER_NEW_NODES={node2}"
Note:
Use the
-noCopy
option because the Oracle home on the destination node is already fully populated with software.
If you have a shared Oracle home on a shared file system that is not Oracle ACFS, then you must first create a mount point for the Oracle RAC database home on the target node, mount and attach the Oracle RAC database home, and update the Oracle
Inventory, as follows:
1.
Run the srvctl config database -db db_name
command on an existing node in the cluster to obtain the mount point information.
2.
3.
Mount the file system that hosts the Oracle RAC database home.
Run the following command as the user that installed Oracle RAC from the
Oracle_home\oui\bin
directory on the node you are adding to add the Oracle
RAC database home:
4.
setup.exe -attachHome ORACLE_HOME="ORACLE_HOME" "CLUSTER_NODES=
local_node_name}" LOCAL_NODE="node_name" ORACLE_HOME_NAME="home_name"
Update the Oracle Inventory as the user that installed Oracle RAC, as follows: setup.exe -updateNodeList ORACLE_HOME=mount_point_path
"CLUSTER_NODES={node_list}"
In the preceding command,
node_list
refers to a list of all nodes where the
Oracle RAC database home is installed, including the node you are adding.
Note:
Oracle recommends that you back up your voting disk and Oracle Cluster
Registry (OCR) files after you complete the node addition process.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Adding Administrator-Managed Oracle RAC Database Instances to Target
You can use either Oracle Enterprise Manager or DBCA to add Oracle
RAC database instances to the target nodes.
Adding and Deleting Oracle RAC from Nodes on Windows Systems 12-3
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
Adding Administrator-Managed Oracle RAC Database Instances to Target Nodes
You can use either Oracle Enterprise Manager or DBCA to add Oracle RAC database instances to the target nodes.
This section describes using DBCA to add Oracle RAC database instances.
These tools guide you through the following tasks:
• Creating a new database instance on each target node
• Creating and configuring high availability components
• Creating the Oracle Net configuration for a non-default listener from the Oracle home
• Starting the new instance
• Creating and starting services if you entered services information on the Services
Configuration page
After adding the instances to the target nodes, you should perform any necessary service configuration procedures.
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
Workload Management with Dynamic Database Services
Workload management includes load balancing, enabling clients for
Oracle Real Application Clusters (Oracle RAC), distributed transaction processing, and services.
Using DBCA in Interactive Mode to Add Database Instances to Target Nodes
To add a database instance to a target node using DBCA in interactive mode, perform the following steps:
1.
Ensure that your existing nodes have the Oracle home environment variable set correctly.
2.
3.
4.
5.
Start DBCA by entering dbca
at the system prompt from the
Oracle_home\bin directory on an existing node.
DBCA performs certain CVU checks while running. However, you can also run
CVU from the command line to perform various verifications.
On the Database Operations page, select Instance Management, click Next, and
DBCA displays the Instance Management page.
Select Add Instance and click Next. DBCA displays the List of Cluster Databases page that shows the databases and their current status, such as
ACTIVE
or
INACTIVE
.
From the List of Cluster Databases page, select the active Oracle RAC database to which you want to add an instance. Click Next and DBCA displays the List of
Cluster Database Instances page showing the names of the existing instances for the Oracle RAC database that you selected.
12-4 Oracle Real Application Clusters Administration and Deployment Guide
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
6.
7.
Click Next to add a new instance and DBCA displays the Adding an Instance page.
On the Adding an Instance page, enter the instance name in the field at the top of this page if the instance name that DBCA provides does not match your existing instance naming scheme. Then select the new node name from the list.
Note:
If you installed the Oracle home with the Oracle Home User option, then
DBCA prompts you for that password on this page.
8.
Review the information on the Summary Page and click Finish to initiate instance addition operation. DBCA displays a progress dialog showing DBCA performing the instance addition operation.
Creating the OraMTS Service for Microsoft Transaction Server
Oracle Services for Microsoft Transaction Server (OraMTS) permit Oracle databases to be used as resource managers in Microsoft application-coordinated transactions.
OraMTS acts as a proxy for the Oracle database to the Microsoft Distributed
Transaction Coordinator (MSDTC). As a result, OraMTS provides client-side connection pooling and allows client components that leverage Oracle to participate in promotable and distributed transactions. In addition, OraMTS can operate with Oracle databases running on any operating system, given that the services themselves are run on Windows.
On releases earlier than Oracle Database 12c, the OraMTS service was created as part of a software-only installation. Starting with Oracle Database 12c, you must use a configuration tool to create this service.
Create the OraMTS service after adding a node or performing a software-only installation for Oracle RAC, as follows:
1.
Open a command window.
2.
3.
Change directories to
%ORACLE_HOME%\bin
.
Run the OraMTSCtl utility to create the OraMTS Service, where
host_name
is a list of nodes on which the service should be created:
C:\..bin> oramtsctl.exe -new -host host_name
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Oracle Services for Microsoft Transaction Server Developer's Guide for Microsoft
Windows
Using DBCA in Silent Mode to Add Database Instances to Target Nodes
Add instances to nodes on which you have extended an Oracle Clusterware home and an Oracle Database home.
Use DBCA in silent mode with the following syntax: dbca -silent -addInstance -nodeList node_name -gdbName gdb_name
[-instanceName instance_name -sysDBAUserName sysdba -sysDBAPassword password]
Adding and Deleting Oracle RAC from Nodes on Windows Systems 12-5
Deleting Oracle RAC from a Cluster Node
See Also:
Table 11-1 for definitions of the variables used in the preceding syntax
Perform any necessary service configuration procedures.
Related Topics:
Workload Management with Dynamic Database Services
Workload management includes load balancing, enabling clients for
Oracle Real Application Clusters (Oracle RAC), distributed transaction processing, and services.
Deleting Oracle RAC from a Cluster Node
To remove Oracle RAC from a cluster node, you must delete the database instance and the Oracle RAC software before removing the node from the cluster.
Note:
If there are no database instances on the node you want to delete, then remove
Oracle RAC.
This section includes the following procedures to delete nodes from clusters in an
Oracle RAC environment:
•
Deleting Instances from Oracle RAC Databases
•
•
Deleting Nodes from the Cluster
Related Topics:
This procedure removes the Oracle RAC software from the node you are deleting from the cluster and updates inventories on the remaining nodes.
Deleting Instances from Oracle RAC Databases
The procedures for deleting instances are different for policy-managed and administrator-managed databases.
Deleting a policy-managed database instance involves reducing the size of the server pool in which the database instance resides. Deleting an administrator-managed database instance involves using DBCA to delete the database instance.
Deleting Policy-Managed Databases
To delete a policy-managed database, decrease the size of the server pool in which a database instance resides. This effectively removes the instance without having to remove the Oracle RAC software from the node or the node from the cluster.
12-6 Oracle Real Application Clusters Administration and Deployment Guide
Deleting Oracle RAC from a Cluster Node
For example, you can delete a policy-managed database by running the following commands on any node in the cluster:
$ srvctl stop instance -db db_unique_name -node node_name
$ srvctl relocate server -servers "server_name_list" -serverpool Free
The first command stops on the instance on a particular node and the second command moves the list of servers out of their current server pool and into the Free server pool.
Deleting Instances from Administrator-Managed Databases
Note:
Before deleting an instance from an Oracle RAC database using SRVCTL, do the following:
• If you have services configured, then relocate the services
• Modify the services so that each service can run on one of the remaining instances
• Ensure that the instance to be removed from an administrator-managed database is neither a preferred nor an available instance of any service
Related Topics:
This procedure removes the Oracle RAC software from the node you are deleting from the cluster and updates inventories on the remaining nodes.
Administering Services with SRVCTL
When you create a service using SRVCTL, you must start the service with a separate SRVCTL command.
Oracle Database 2 Day + Real Application Clusters Guide
Using DBCA in Interactive Mode to Delete Instances from Nodes
To delete an instance using DBCA in interactive mode, perform the following steps:
1.
Verify there is a current backup of OCR.
Run the ocrconfig -showbackup
command to ensure there is a valid backup.
2.
3.
4.
Start DBCA.
Start DBCA on a node other than the node that hosts the instance that you want to delete. The database and the instance that you plan to delete should continue to be started and running during this step.
On the DBCA Operations page, select Instance Management, click Next, and
DBCA displays the Instance Management page.
On the Instance Management page, select Delete Instance, click Next, and DBCA displays the List of Cluster Databases page.
Adding and Deleting Oracle RAC from Nodes on Windows Systems 12-7
Deleting Oracle RAC from a Cluster Node
5.
6.
7.
8.
9.
Select an Oracle RAC database from which to delete an instance. Click Next and
DBCA displays the List of Cluster Database Instances page. The List of Cluster
Database Instances page shows the instances that are associated with the Oracle
RAC database that you selected and the status of each instance.
On the List of Cluster Databases page, select the Oracle RAC database from which to delete the instance, as follows:
a.
b.
On the List of Cluster Database Instances page, DBCA displays the instances that are associated with the Oracle RAC database that you selected and the status of each instance. Select the cluster database from which you will delete the instance. Click Finish.
Click OK on the Confirmation dialog to proceed to delete the instance.
c.
Click OK on the next Confirmation dialog to delete the instance and related
Optimal Flexible Architecture (OFA) directory structure.
DBCA displays a progress dialog showing that DBCA is deleting the instance.
During this operation, DBCA removes the instance and the instance's Oracle
Net configuration.
Click No and exit DBCA or click Yes to perform another operation. If you click Yes, then DBCA displays the Operations page.
Verify that the dropped instance's redo thread has been removed using SQL*Plus to query the
V$LOG
view from an existing instance. If the redo thread is not disabled, then disable the thread. For example:
SQL> ALTER DATABASE DISABLE THREAD 2;
Verify that the instance has been removed from OCR by running the following command, where
db_unique_name
is the name of the database: srvctl config database -db db_unique_name
If you are deleting more than one node, then repeat these steps to delete the instances from all the nodes that you are going to delete.
Using DBCA in Silent Mode to Delete Instances from Nodes
You can use DBCA in silent mode to delete a database instance from a node.
Run the following command, where the variables are the same as those shown in
Table 11-1 for the DBCA command to add an instance. Provide a node name only if
you are deleting an instance from a node other than the one on where DBCA is running as shown in the following example where
password
is the SYSDBA password: dbca -silent -deleteInstance [-nodeList node_name] -gdbName gdb_name
-instanceName instance_name [-sysDBAUserName sysdba] [-sysDBAPassword password]
At this point, you have accomplished the following:
• Deregistered the selected instance from its associated Oracle Net Services listeners
• Deleted the selected database instance from the instance's configured node
• Removed the Oracle Net configuration
12-8 Oracle Real Application Clusters Administration and Deployment Guide
Deleting Oracle RAC from a Cluster Node
• Deleted the Oracle Flexible Architecture directory structure from the instance's configured node.
Removing Oracle RAC
This procedure removes the Oracle RAC software from the node you are deleting from the cluster and updates inventories on the remaining nodes.
1.
If there is a listener in the Oracle RAC home on the node you are deleting, then you must disable and stop it before deleting the Oracle RAC software. Run the following commands on any node in the cluster, specifying the name of the listener and the name of the node you are deleting:
2.
C:\srvctl disable listener -listener listener_name -node name_of_node_to_delete
C:\srvctl stop listener -listener listener_name -node name_of_node_to_delete
Deinstall the Oracle home from the node that you are deleting by running the following command from the
Oracle_home\deinstall
directory: deinstall -local
If you have a shared Oracle RAC home, then append the
-cfs
option to the command example in this step and provide a complete path location for the cluster file system.
Deleting Nodes from the Cluster
After you delete the instance, you can begin the process of deleting the node from the cluster. You accomplish this by running scripts on the node you want to delete to remove the Oracle Clusterware installation and you run scripts on the remaining nodes to update the node list.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Oracle Grid Infrastructure Installation and Upgrade Guide for Microsoft Windows x64
(64-Bit)
Adding and Deleting Oracle RAC from Nodes on Windows Systems 12-9
Deleting Oracle RAC from a Cluster Node
12-10 Administration and Deployment Guide
13
Design and Deployment Techniques
This chapter briefly describes database design and deployment techniques for Oracle
Real Application Clusters (Oracle RAC) environments. It also describes considerations for high availability and provides general guidelines for various Oracle RAC deployments.
This chapter includes the following topics:
•
Deploying Oracle RAC for High Availability
•
General Design Considerations for Oracle RAC
•
General Database Deployment Topics for Oracle RAC
Deploying Oracle RAC for High Availability
Many customers implement Oracle RAC to provide high availability for their Oracle
Database applications. For true high availability, you must make the entire infrastructure of the application highly available. This requires detailed planning to ensure there are no single points of failure throughout the infrastructure. Even though
Oracle RAC makes your database highly available, if a critical application becomes unavailable, then your business can be negatively affected. For example, if you choose to use the Lightweight Directory Access Protocol (LDAP) for authentication, then you must make the LDAP server highly available. If the database is up but the users cannot connect to the database because the LDAP server is not accessible, then the entire system appears to be down to your users.
This section includes the following topics:
•
About Designing a High Availability System
•
Best Practices for Deploying Oracle RAC in a High Availability Environment
•
Consolidating Multiple Applications in a Database or Multiple Databases in a
•
About Designing a High Availability System
For mission critical systems, you must be able to perform failover and recovery, and your environment must be resilient to all types of failures.
For mission critical systems, you must be able to perform failover and recovery, and your environment must be resilient to all types of failures. To reach these goals, start by defining service level requirements for your business. The requirements should include definitions of maximum transaction response time and recovery expectations for failures within the datacenter (such as for node failure) or for disaster recovery (if the entire data center fails). Typically, the service level objective is a target response
Design and Deployment Techniques 13-1
Deploying Oracle RAC for High Availability time for work, regardless of failures. Determine the recovery time for each redundant component. Even though you may have hardware components that are running in an active/active mode, do not assume that if one component fails the other hardware components can remain operational while the faulty components are being repaired.
Also, when components are running in active/passive mode, perform regular tests to validate the failover time. For example, recovery times for storage channels can take minutes. Ensure that the outage times are within your business' service level agreements, and where they are not, work with the hardware vendor to tune the configuration and settings.
When deploying mission critical systems, the testing should include functional testing, destructive testing, and performance testing. Destructive testing includes the injection of various faults in the system to test the recovery and to make sure it satisfies the service level requirements. Destructive testing also allows the creation of operational procedures for the production system.
To help you design and implement a mission critical or highly available system,
Oracle provides a range of solutions for every organization regardless of size. Small workgroups and global enterprises alike are able to extend the reach of their critical business applications. With Oracle and the Internet, applications and their data are now reliably accessible everywhere, at any time. The Oracle Maximum Availability
Architecture (MAA) is the Oracle best practices blueprint that is based on proven
Oracle high availability technologies and recommendations. The goal of the MAA is to remove the complexity in designing an optimal high availability architecture.
Related Topics:
Oracle Database High Availability Overview
Oracle Maximum Availability Architecture (MAA)
Best Practices for Deploying Oracle RAC in a High Availability Environment
Applications can take advantage of many Oracle Database, Oracle Clusterware, and
Oracle RAC features and capabilities to minimize or mask any failure in the Oracle
RAC environment. For example, you can:
• Remove TCP/IP timeout waits by using the VIP address to connect to the database.
• Create detailed operational procedures and ensure you have the appropriate support contracts in place to match defined service levels for all components in the infrastructure.
• Take advantage of the Oracle RAC Automatic Workload Management features such as connect time failover, Fast Connection Failover, Fast Application
Notification, and the Load Balancing Advisory.
• Place voting disks on separate volume groups to mitigate outages due to slow I/O throughput. To survive the failure of x voting devices, configure 2x + 1 mirrors.
• Use Oracle Database Quality of Service Management (Oracle Database QoS
Management) to monitor your system and detect performance bottlenecks.
• Place OCR with I/O service times in the order of 2 milliseconds (ms) or less.
• Tune database recovery using the
FAST_START_MTTR_TARGET
initialization parameter.
13-2 Oracle Real Application Clusters Administration and Deployment Guide
Deploying Oracle RAC for High Availability
• Use Oracle Automatic Storage Management (Oracle ASM) to manage database storage.
• Ensure that strong change control procedures are in place.
• Check the surrounding infrastructure for high availability and resiliency, such as
LDAP, NIS, and DNS. These entities affect the availability of your Oracle RAC database. If possible, perform a local backup procedure routinely.
• Use Oracle Enterprise Manager to administer your entire Oracle RAC environment, not just the Oracle RAC database. Use Oracle Enterprise Manager to create and modify services, and to start and stop the cluster database instances and the cluster database.
• Use Recovery Manager (RMAN) to back up, restore, and recover data files, control files, server parameter files (SPFILEs) and archived redo log files. You can use
RMAN with a media manager to back up files to external storage. You can also configure parallelism when backing up or recovering Oracle RAC databases. In
Oracle RAC, RMAN channels can be dynamically allocated across all of the Oracle
RAC instances. Channel failover enables failed operations on one node to continue on another node. You can start RMAN from Oracle Enterprise Manager
Backup Manager or from the command line.
• If you use sequence numbers, then always use
CACHE
with the
NOORDER
option for optimal performance in sequence number generation. With the
CACHE
option, however, you may have gaps in the sequence numbers. If your environment cannot tolerate sequence number gaps, then use the
NOCACHE
option or consider pre-generating the sequence numbers. If your application requires sequence number ordering but can tolerate gaps, then use
CACHE
and
ORDER
to cache and order sequence numbers in Oracle RAC. If your application requires ordered sequence numbers without gaps, then use
NOCACHE
and
ORDER
. The
NOCACHE and
ORDER
combination has the most negative effect on performance compared to other caching and ordering combinations.
Note:
If your environment cannot tolerate sequence number gaps, then consider pregenerating the sequence numbers or use the
ORDER
and
CACHE
options.
• If you use indexes, then consider alternatives, such as reverse key indexes to optimize index performance. Reverse key indexes are especially helpful if you have frequent inserts to one side of an index, such as indexes that are based on insert date.
Related Topics:
Workload Management with Dynamic Database Services
Workload management includes load balancing, enabling clients for
Oracle Real Application Clusters (Oracle RAC), distributed transaction processing, and services.
Oracle Database 2 Day + Real Application Clusters Guide
Configuring Recovery Manager and Archiving
Design and Deployment Techniques 13-3
Deploying Oracle RAC for High Availability
Consolidating Multiple Applications in a Database or Multiple Databases in a Cluster
Many people want to consolidate multiple applications in a single database or consolidate multiple databases in a single cluster. Oracle Clusterware and Oracle RAC support both types of consolidation.
Creating a cluster with a single pool of storage managed by Oracle ASM provides the infrastructure to manage multiple databases whether they are single instance databases or Oracle RAC databases.
Managing Capacity During Consolidation
With Oracle RAC databases, you can adjust the number of instances and which nodes run instances for a given database, based on workload requirements. Features such as cluster-managed services allow you to manage multiple workloads on a single database or across multiple databases.
It is important to properly manage the capacity in the cluster when adding work. The processes that manage the cluster—including processes both from Oracle Clusterware and the database—must be able to obtain CPU resources in a timely fashion and must be given higher priority in the system. Oracle Database Quality of Service
Management (Oracle Database QoS Management) can assist consolidating multiple applications in a cluster or database by dynamically allocating CPU resources to meet performance objectives. You can also use cluster configuration policies to manage resources at the cluster level.
Related Topics:
Oracle Database Quality of Service Management User's Guide
Managing the Global Cache Service Processes During Consolidation
Oracle recommends that the number of real time Global Cache Service Processes
(LMSn) on a server is less than or equal to the number of processors. (Note that this is the number of recognized CPUs that includes cores. For example, a dual-core CPU is considered to be two CPUs.) It is important that you load test your system when adding instances on a node to ensure that you have enough capacity to support the workload.
If you are consolidating many small databases into a cluster, you may want to reduce the number of LMSn created by the Oracle RAC instance. By default, Oracle Database calculates the number of processes based on the number of CPUs it finds on the server.
This calculation may result in more LMSn processes than is needed for the Oracle RAC instance. One LMS process may be sufficient for up to 4 CPUs.To reduce the number of LMSn processes, set the
GC_SERVER_PROCESSES
initialization parameter minimally to a value of 1. Add a process for every four CPUs needed by the application. In general, it is better to have few busy LMSn processes. Oracle Database calculates the number of processes when the instance is started, and you must restart the instance to change the value.
Using a Database Cloud for Consolidation
A database cloud is a set of databases integrated by the Global Data Services framework into a single virtual server that offers one or more global services, while ensuring high performance, availability and optimal utilization of resources.
Global Data Services manages these virtualized resources with minimum administration overhead, and allows the database cloud to quickly scale to handle
13-4 Oracle Real Application Clusters Administration and Deployment Guide
Deploying Oracle RAC for High Availability additional client requests. The databases that constitute a cloud can be globally distributed, and clients can connect to the database cloud by simply specifying a service name, without needing to know anything about the components and topology of the cloud.
A database cloud can be comprised of multiple database pools. A
is a set of databases within a database cloud that provide a unique set of global services and belong to a certain administrative domain. Partitioning of cloud databases into multiple pools simplifies service management and provides higher security by allowing each pool to be administered by a different administrator. A database cloud
can span multiple geographic regions. A
is a logical boundary that contains database clients and servers that are considered to be close to each other. Usually a region corresponds to a data center, but multiple data centers can be in the same region if the network latencies between them satisfy the service-level agreements of the applications accessing these data centers.
Global services enable you to integrate locally and globally distributed, loosely coupled, heterogeneous databases into a scalable and highly available private database cloud. This database cloud can be shared by clients around the globe. Using a private database cloud provides optimal utilization of available resources and simplifies the provisioning of database services.
Related Topics:
Oracle Database Global Data Services Concepts and Administration Guide
Scalability of Oracle RAC
Oracle RAC provides concurrent, transactionally consistent access to a single copy of the data from multiple systems. It provides scalability beyond the capacity of a single server. If your application scales transparently on symmetric multiprocessing (SMP) servers, then it is realistic to expect the application to scale well on Oracle RAC, without the need to make changes to the application code.
Traditionally, when a database server runs out of capacity, it is replaced with a new larger server. As servers grow in capacity, they become more expensive. However, for
Oracle RAC databases, you have alternatives for increasing the capacity:
• You can migrate applications that traditionally run on large SMP servers to run on clusters of small servers.
• You can maintain the investment in the current hardware and add a new server to the cluster (or create or add a new cluster) to increase the capacity.
Adding servers to a cluster with Oracle Clusterware and Oracle RAC does not require an outage. As soon as the new instance is started, the application can take advantage of the extra capacity.
All servers in the cluster must run the same operating system and same version of
Oracle Database but the servers do not have to have the same capacity. With Oracle
RAC, you can build a cluster that fits your needs, whether the cluster is made up of servers where each server is a two-CPU commodity server or clusters where the servers have 32 or 64 CPUs in each server. The Oracle parallel execution feature allows a single SQL statement to be divided up into multiple processes, where each process completes a subset of work. In an Oracle RAC environment, you can define the parallel processes to run only on the instance where the user is connected or to run across multiple instances in the cluster.
Design and Deployment Techniques 13-5
General Design Considerations for Oracle RAC
Related Topics:
Cloning Oracle RAC to Nodes in a New Cluster
This chapter describes how to clone Oracle Real Application Clusters
(Oracle RAC) database homes on Linux and UNIX systems to nodes in a new cluster.
Using Cloning to Extend Oracle RAC to Nodes in the Same Cluster
Adding and Deleting Oracle RAC from Nodes on Linux and UNIX Systems
Extend an existing Oracle Real Application Clusters (Oracle RAC) home to other nodes and instances in the cluster, and delete Oracle RAC from nodes and instances in the cluster.
Adding and Deleting Oracle RAC from Nodes on Windows Systems
General Design Considerations for Oracle RAC
This section briefly describes database design and deployment techniques for Oracle
RAC environments. It also describes considerations for high availability and provides general guidelines for various Oracle RAC deployments.
Consider performing the following steps during the design and development of applications that you are deploying on an Oracle RAC database:
1.
2.
3.
4.
Tune the design and the application
Tune the memory and I/O
Tune contention
Tune the operating system
Note:
If an application does not scale on an SMP system, then moving the application to an Oracle RAC database cannot improve performance.
Consider using hash partitioning for insert-intensive online transaction processing
(OLTP) applications. Hash partitioning:
• Reduces contention on concurrent inserts into a single database structure
• Affects sequence-based indexes when indexes are locally partitioned with a table and tables are partitioned on sequence-based keys
• Is transparent to the application
If you use hash partitioning for tables and indexes for OLTP environments, then you can greatly improve performance in your Oracle RAC database. Note that you cannot use index range scans on an index with hash partitioning.
General Database Deployment Topics for Oracle RAC
This section describes considerations when deploying Oracle RAC databases. Oracle
RAC database performance is not compromised if you do not employ these
13-6 Oracle Real Application Clusters Administration and Deployment Guide
General Database Deployment Topics for Oracle RAC techniques. If you have an effective noncluster design, then your application will run well on an Oracle RAC database.
This section includes the following topics:
•
•
Object Creation and Performance in Oracle RAC
•
Node Addition and Deletion and the SYSAUX Tablespace in Oracle RAC
•
Distributed Transactions and Oracle RAC
•
Deploying OLTP Applications in Oracle RAC
•
Flexible Implementation with Cache Fusion
•
Deploying Data Warehouse Applications with Oracle RAC
•
Data Security Considerations in Oracle RAC
Tablespace Use in Oracle RAC
In addition to using locally managed tablespaces, you can further simplify space administration by using automatic segment space management (ASSM) and automatic undo management.
ASSM distributes instance workloads among each instance's subset of blocks for inserts. This improves Oracle RAC performance because it minimizes block transfers.
To deploy automatic undo management in an Oracle RAC environment, each instance must have its own undo tablespace.
Object Creation and Performance in Oracle RAC
As a general rule, only use DDL statements for maintenance tasks and avoid executing
DDL statements during peak system operation periods. In most systems, the amount of new object creation and other DDL statements should be limited. Just as in noncluster Oracle databases, excessive object creation and deletion can increase performance overhead.
Node Addition and Deletion and the SYSAUX Tablespace in Oracle RAC
If you add nodes to your Oracle RAC database environment, then you may need to increase the size of the
SYSAUX
tablespace. Conversely, if you remove nodes from
, then you may be able to reduce the size of your
SYSAUX tablespace.
See Also:
Your platform-specific Oracle RAC installation guide for guidelines about sizing the
SYSAUX
tablespace for multiple instances
Distributed Transactions and Oracle RAC
If you are running XA Transactions in an Oracle RAC environment and the performance is poor, then direct all branches of a tightly coupled distributed
Design and Deployment Techniques 13-7
General Database Deployment Topics for Oracle RAC transaction to the same instance by creating multiple Oracle Distributed Transaction
Processing (DTP) services, with one or more on each Oracle RAC instance.
Each DTP service is a singleton service that is available on one and only one Oracle
RAC instance. All access to the database server for distributed transaction processing must be done by way of the DTP services. Ensure that all of the branches of a single global distributed transaction use the same DTP service. In other words, a network connection descriptor, such as a TNS name, a JDBC URL, and so on, must use a DTP service to support distributed transaction processing.
Related Topics:
Distributed Transaction Processing in Oracle RAC
Oracle Database Development Guide
Deploying OLTP Applications in Oracle RAC
Cache Fusion makes Oracle RAC databases the optimal deployment servers for online transaction processing (OLTP) applications. This is because these types of applications require:
• High availability if there are failures
• Scalability to accommodate increased system demands
• Load balancing according to demand fluctuations
The high availability features of Oracle Database and Oracle RAC can re-distribute and load balance workloads to surviving instances without interrupting processing.
Oracle RAC also provides excellent scalability so that if you add or replace a node, then Oracle Database re-masters resources and re-distributes processing loads.
Flexible Implementation with Cache Fusion
To accommodate the frequently changing workloads of online transaction processing systems, Oracle RAC remains flexible and dynamic despite changes in system load and system availability. Oracle RAC addresses a wide range of service levels that, for example, fluctuate due to:
• Varying user demands
• Peak scalability issues like trading storms (bursts of high volumes of transactions)
• Varying availability of system resources
Deploying Data Warehouse Applications with Oracle RAC
This section discusses how to deploy data warehouse systems in Oracle RAC environments by briefly describing the data warehouse features available in shared disk architectures.
This section includes the following topics:
•
Speed-Up for Data Warehouse Applications on Oracle RAC
•
Parallel Execution in Data Warehouse Systems and Oracle RAC
13-8 Oracle Real Application Clusters Administration and Deployment Guide
General Database Deployment Topics for Oracle RAC
Speed-Up for Data Warehouse Applications on Oracle RAC
Oracle RAC is ideal for data warehouse applications because it augments the noncluster benefits of Oracle Database. Oracle RAC does this by maximizing the processing available on all of the nodes that belong to an Oracle RAC database to provide speed-up for data warehouse systems.
The query optimizer considers parallel execution when determining the optimal execution plans. The default cost model for the query optimizer is CPU+I/O and the cost unit is time. In Oracle RAC, the query optimizer dynamically computes intelligent defaults for parallelism based on the number of processors in the nodes of the cluster.
An evaluation of the costs of alternative access paths, table scans versus indexed access, for example, takes into account the degree of parallelism available for the operation. This results in Oracle Database selecting the execution plans that are optimized for your Oracle RAC configuration.
Parallel Execution in Data Warehouse Systems and Oracle RAC
Parallel execution uses multiple processes to run SQL statements on one or more CPUs and is available on both noncluster Oracle databases and Oracle RAC databases.
Oracle RAC takes full advantage of parallel execution by distributing parallel processing across all available instances. The number of processes that can participate in parallel operations depends on the degree of parallelism assigned to each table or index.
Related Topics:
Oracle Database Performance Tuning Guide
Oracle Database Concepts
Data Security Considerations in Oracle RAC
This section describes the following two Oracle RAC security considerations:
•
Transparent Data Encryption and Keystores
•
Windows Firewall Considerations
Transparent Data Encryption and Keystores
Oracle Database enables Oracle RAC nodes to share the
eliminates the need to manually copy and synchronize the keystore across all nodes.
Oracle recommends that you create the keystore on a shared file system. This allows all instances to access the same shared keystore.
Oracle RAC uses keystores in the following ways:
1.
2.
Any keystore operation, like opening or closing the keystore, performed on any one Oracle RAC instance is applicable for all other Oracle RAC instances. This means that when you open and close the keystore for one instance, then it opens and closes the keystore for all Oracle RAC instances.
When using a shared file system, ensure that the
ENCRYPTION_WALLET_LOCATION
parameter for all Oracle RAC instances points to the same shared keystore location. The security administrator must also ensure security of the shared keystore by assigning appropriate directory permissions.
Design and Deployment Techniques 13-9
General Database Deployment Topics for Oracle RAC
Note:
If Oracle Automatic Storage Management Cluster File System (Oracle ACFS) is available for your operating system, then Oracle recommends that you store the keystore in Oracle ACFS. If you do not have Oracle ACFS in Oracle ASM, then use the Oracle ASM Configuration Assistant (ASMCA) to create it. You must add the mount point to the sqlnet.ora
file in each instance, as follows:
ENCRYPTION_WALLET_LOCATION=
(SOURCE = (METHOD = FILE)
(METHOD_DATA =
(DIRECTORY = /opt/oracle/acfsmounts/data_keystore)))
This file system is mounted automatically when the instances start. Opening and closing the keystore, and commands to set or rekey and rotate the TDE master encryption key, are synchronized between all nodes.
3.
A master key rekey performed on one instance is applicable for all instances.
When a new Oracle RAC node comes up, it is aware of the current keystore open or close status.
4.
Do not issue any keystore
ADMINISTER KEY MANAGEMENT SET KEYSTORE
OPEN
or
CLOSE
SQL statements while setting up or changing the master key.
Deployments where shared storage does not exist for the keystore require that each
Oracle RAC node maintain a local keystore. After you create and provision a keystore on a single node, you must copy the keystore and make it available to all of the other nodes, as follows:
• For systems using Transparent Data Encryption with encrypted keystores, you can use any standard file transport protocol, though Oracle recommends using a secured file transport.
• For systems using Transparent Data Encryption with auto-login keystores, file transport through a secured channel is recommended.
To specify the directory in which the keystore must reside, set the or
ENCRYPTION_WALLET_LOCATION
parameter in the sqlnet.ora
file. The local copies of the keystore need not be synchronized for the duration of Transparent Data
Encryption usage until the server key is re-keyed though the
ADMINISTER KEY
MANAGEMENT SET KEY
SQL statement. Each time you issue the
ADMINISTER KEY
MANAGEMENT SET KEY
statement on a database instance, you must again copy the keystore residing on that node and make it available to all of the other nodes. Then, you must close and reopen the keystore on each of the nodes. To avoid unnecessary administrative overhead, reserve re-keying for exceptional cases where you believe that the server master key may have been compromised and that not re-keying it could cause a serious security problem.
Related Topics:
Oracle Database Advanced Security Guide
Windows Firewall Considerations
By default, all installations of Windows Server 2003 Service Pack 1 and higher enable the Windows Firewall to block virtually all TCP network ports to incoming connections. As a result, any Oracle products that listen for incoming connections on a
13-10 Oracle Real Application Clusters Administration and Deployment Guide
General Database Deployment Topics for Oracle RAC
TCP port will not receive any of those connection requests, and the clients making those connections will report errors.
Depending upon which Oracle products you install and how they are used, you may need to perform additional Windows post-installation configuration tasks so that the
Firewall products are functional on Windows Server 2003.
Related Topics:
Oracle Grid Infrastructure Installation and Upgrade Guide for Microsoft Windows x64
(64-Bit)
Design and Deployment Techniques 13-11
General Database Deployment Topics for Oracle RAC
13-12 Administration and Deployment Guide
14
Monitoring Performance
This chapter describes how to monitor and tune Oracle Real Application Clusters
(Oracle RAC) performance.
This chapter includes the following topics:
•
Overview of Monitoring and Tuning Oracle RAC Databases
•
Verifying the Interconnect Settings for Oracle RAC
•
Influencing Interconnect Processing
•
Performance Views in Oracle RAC
•
Creating Oracle RAC Data Dictionary Views with CATCLUST.SQL
•
Oracle RAC Performance Statistics
•
Automatic Workload Repository in Oracle RAC Environments
•
Active Session History Reports for Oracle RAC
•
Monitoring Oracle RAC Statistics and Wait Events
Overview of Monitoring and Tuning Oracle RAC Databases
This section includes the following topics:
•
Monitoring Oracle RAC and Oracle Clusterware
•
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
Oracle Database 2 Day DBA
Oracle Database 2 Day + Performance Tuning Guide
Oracle Clusterware Administration and Deployment Guide
Monitoring Oracle RAC and Oracle Clusterware
Using Oracle Enterprise Manager is the preferred method for monitoring Oracle RAC and Oracle Clusterware. Oracle Enterprise Manager is an Oracle Web-based integrated management solution for monitoring and administering your computing environment. From any location where you can access a web browser, you can manage Oracle RAC databases, application servers, host computers, and Web applications, in addition to related hardware and software. For example, you can
Monitoring Performance 14-1
Overview of Monitoring and Tuning Oracle RAC Databases monitor your Oracle RAC database performance from your office, home, or a remote site, if you have access to a Web browser.
Oracle Enterprise Manager Cloud Control is cluster-aware and provides a central console to manage your cluster database. From the Cluster Database Home page, you can do all of the following:
• View the overall system status, such as the number of nodes in the cluster and their current status. This high-level view capability means that you do not have to access each individual database instance for details if you just want to see inclusive, aggregated information.
• View alert messages aggregated across all the instances with lists for the source of each alert message. An alert message is an indicator that signifies that a particular metric condition has been encountered. A metric is a unit of measurement used to report the system's conditions.
• Review issues that are affecting the entire cluster and those issues that are affecting individual instances.
• Monitor cluster cache coherency statistics to help you identify processing trends and optimize performance for your Oracle RAC environment. Cache coherency statistics measure how well the data in caches on multiple instances is synchronized. If the data caches are completely synchronized with each other, then reading a memory location from the cache on any instance will return the most recent data written to that location from any cache on any instance.
Oracle Enterprise Manager accumulates data over specified periods of time, called collection-based data. Oracle Enterprise Manager also provides current data, called real-time data.
Oracle Database 2 Day + Real Application Clusters Guide
provides complete information about monitoring performance with Oracle Enterprise Manager, including:
• Automatic Database Diagnostic Monitor and Oracle RAC Performance
•
The Cluster Database Home Page
•
•
The Cluster Database Performance Page
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
The Cluster Database Home Page
You can use Oracle Enterprise Manager with a client browser to monitor the status of both Oracle Clusterware and the Oracle RAC environments. Monitoring can include such things as:
• Notification if there are any VIP relocations
• Status of the Oracle Clusterware on each node of the cluster using information obtained through the Cluster Verification Utility ( cluvfy
)
• Notification if node applications ( nodeapps
) start or stop
14-2 Oracle Real Application Clusters Administration and Deployment Guide
Overview of Monitoring and Tuning Oracle RAC Databases
• Notification of issues in the Oracle Clusterware alert log for OCR, voting disk issues (if any), and node evictions
The Cluster Database Home page is similar to a noncluster Database Home page.
However, on the Cluster Database Home page, Oracle Enterprise Manager displays the system state and availability. This includes a summary about alert messages and job activity, and links to all the database and Oracle Automatic Storage Management
(Oracle ASM) instances. For example, you can track problems with services on the cluster including when a service is not running on all of the preferred instances or when a service response time threshold is not being met.
The Interconnects Page
You can use the Oracle Enterprise Manager Interconnects page to monitor the Oracle
Clusterware environment. The Interconnects page shows the public and private interfaces on the cluster and the load contributed by database instances on the interconnect, including:
• Overall throughput across the private interconnect
• Notification if a database instance is using public interface due to misconfiguration
• Throughput and errors (if any) on the interconnect
• Throughput contributed by individual instances on the interconnect
All of this information is also available as collections that have a historic view, which is useful with cluster cache coherency, such as when diagnosing problems related to cluster wait events. You can access the Interconnects page by clicking the Interconnect tab on the Cluster Database home page or clicking the Interconnect Alerts link under
Diagnostic Findings on the Oracle RAC database home page.
The Cluster Database Performance Page
The Oracle Enterprise Manager Cluster Database Performance page provides a quick glimpse of the performance statistics for a database.
Statistics are rolled up across all the instances in the cluster database in charts. Using the links next to the charts, you can get more specific information and perform any of the following tasks:
• Identify the causes of performance issues.
• Decide whether resources need to be added or redistributed.
• Tune your SQL plan and schema for better optimization.
• Resolve performance issues
The charts on the Cluster Database Performance page include the following:
•
Chart for Cluster Host Load Average
: The Cluster Host Load Average chart in the Cluster Database Performance page shows potential problems that are outside the database. The chart shows maximum, average, and minimum load values for available nodes in the cluster for the previous hour.
•
Chart for Global Cache Block Access Latency
: Each cluster database instance has its own buffer cache in its System Global Area (SGA). Using Cache Fusion, Oracle
RAC environments logically combine each instance's buffer cache to enable the
Monitoring Performance 14-3
Overview of Monitoring and Tuning Oracle RAC Databases database instances to process data as if the data resided on a logically combined, single cache.
•
Chart for Average Active Sessions
: The Average Active Sessions chart in the
Cluster Database Performance page shows potential problems inside the database.
Categories, called wait classes, show how much of the database is using a resource, such as CPU or disk I/O. Comparing CPU time to wait time helps to determine how much of the response time is consumed with useful work rather than waiting for resources that are potentially held by other processes.
•
Chart for Database Throughput
: The Database Throughput charts summarize any resource contention that appears in the Average Active Sessions chart, and also show how much work the database is performing on behalf of the users or applications. The Per Second view shows the number of transactions compared to the number of logons, and the amount of physical reads compared to the redo size per second. The Per Transaction view shows the amount of physical reads compared to the redo size per transaction. Logons is the number of users that are logged on to the database.
In addition, the Top Activity drill down menu on the Cluster Database Performance page enables you to see the activity by wait events, services, and instances. Plus, you can see the details about SQL/sessions by going to a prior point in time by moving the slider on the chart.
The Cluster Database Performance page provides a quick glimpse of the performance statistics for an Oracle RAC database. Statistics are rolled up across all of the instances in the cluster database so that users can identify performance issues without going through all the instances. To help triage the performance issues related to services,
Oracle Enterprise Manager aggregates the activity data at the following levels:
• Aggregate by waits
All the activity data is presented in 12 categories: CPU, Scheduler, User I/O,
System I/O, Concurrency, Application, Commit, Configuration, Administrative,
Network, Cluster and Other. The data presented is rolled up from all of the running instances.
• Aggregate by services
All the activity data is rolled up for each service. When the activity data is presented in this way, it is easy to identify which service is most active, and needs more analysis.
• Aggregate by instances
As a similar effort, the activity data is rolled up for each instance, if services are not the interested ones.
The aggregates are provided on the pages where the activity data is presented including: Database Performance Page, Top Activity Page, Wait Details Page and
Service Details Page.
Related Topics:
Oracle Database 2 Day + Real Application Clusters Guide
Tuning Oracle RAC Databases
All noncluster tuning practices for Oracle Database apply to Oracle RAC databases.
14-4 Oracle Real Application Clusters Administration and Deployment Guide
Verifying the Interconnect Settings for Oracle RAC
Related Topics:
Oracle Database 2 Day + Performance Tuning Guide
Oracle Database Performance Tuning Guide
Verifying the Interconnect Settings for Oracle RAC
Use SQL statements to verify the interconnect settings for Oracle RAC.
The interconnect and internode communication protocols can affect
performance. In addition, the interconnect bandwidth, its latency, and the efficiency of the IPC protocol determine the speed with which Cache Fusion processes block transfers.
To verify the interconnect settings of the Oracle RAC database instance to which you are connected, query the
V$CLUSTER_INTERCONNECTS
and
V
$CONFIGURED_INTERCONNECTS
views. For example:
Example 14-1 Verify Interconnect Settings with V$CLUSTER_INTERCONNECTS
SQL> SELECT * FROM V$CLUSTER_INTERCONNECTS;
NAME IP_ADDRESS IS_PUBLIC SOURCE
--------------- -------------- --- ------------------------------eth2 10.137.20.181 NO Oracle Cluster Repository
Note:
You can query the
GV$CLUSTER_INTERCONNECTS
view to display the entries for all of the instances in the cluster.
Example 14-2 Verify Interconnect Settings with V
$CONFIGURED_INTERCONNECTS
SQL> SELECT * FROM V$CONFIGURED_INTERCONNECTS;
NAME IP_ADDRESS IS_PUBLIC SOURCE
--------------- --------------- --- ------------------------------eth2 10.137.20.181 NO Oracle Cluster Repository eth0 10.137.8.225 YES Oracle Cluster Repository
Influencing Interconnect Processing
Once your interconnect is operative, you cannot significantly influence its performance. However, you can influence an interconnect protocol's efficiency by adjusting the interprocess communication (IPC) buffer sizes.
The Oracle Cluster Registry (OCR) stores your system's interconnect information. Use the Oracle Interface Configuration (OIFCFG) command-line utility oifcfg getif command or the OCRDUMP utility to identify the interconnect that you are using.
You can then change the interconnect that you are using by running an OIFCFG command.
Although you rarely need to set the
CLUSTER_INTERCONNECTS
parameter, you can use it to assign a private network IP address or NIC as in the following example:
CLUSTER_INTERCONNECTS=10.0.0.1
Monitoring Performance 14-5
Performance Views in Oracle RAC
If you are using an operating system-specific vendor IPC protocol, then the trace information may not reveal the IP address.
Notes:
• You can also use OIFCFG command to assign private network or private
IP addresses.
• If your cluster has Oracle Clusterware 12c release 2 (12.2) or later installed, then you can assign either IPv4 or IPv6 addresses to multiple private networks. You must choose one or the other protocol and use that protocol for all of the private networks in the cluster.
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Oracle Clusterware Administration and Deployment Guide
Oracle Database Reference
Performance Views in Oracle RAC
Each instance has a set of instance-specific views, which are prefixed with
V$
.
You can also query global dynamic performance views to retrieve performance information from all of the qualified instances. Global dynamic performance view names are prefixed with
GV$
.
Querying a
GV$
view retrieves the
V$
view information from all qualified instances. In addition to the
V$
information, each
GV$
view contains an extra column named
INST_ID
of data type
NUMBER
. The
INST_ID
column displays the instance number from which the associated
V$
view information was obtained.
You can use the
INST_ID
column as a filter to retrieve
V$
information from a subset of available instances. For example, the following query retrieves the information from the
V$LOCK
view for instances 2 and 5:
SQL> SELECT * FROM GV$LOCK WHERE INST_ID = 2 OR INST_ID = 5;
Related Topics:
Oracle Database Reference
Creating Oracle RAC Data Dictionary Views with CATCLUST.SQL
If you did not create your Oracle RAC database with the Database Configuration
Assistant (DBCA), then you must run the
CATCLUST.SQL
script to create views and tables related to Oracle RAC. You must have
SYSDBA
privileges to run this script.
Related Topics:
Oracle Real Application Clusters Installation Guide
14-6 Oracle Real Application Clusters Administration and Deployment Guide
Oracle RAC Performance Statistics
Oracle RAC Performance Statistics
Oracle RAC statistics appear as message request counters or as timed statistics.
Message request counters include statistics showing the number of certain types of block mode conversions. Timed statistics reveal the total or average time waited for read and write I/O for particular types of operations.
Automatic Workload Repository in Oracle RAC Environments
You can use Automatic Workload Repository to monitor performance statistics related to Oracle RAC databases.
Automatic Workload Repository (AWR)
automatically generates snapshots of the
performance data once every hour and collects the statistics in the workload repository. In Oracle RAC environments, each AWR snapshot captures data from all active instances in the cluster. The data for each snapshot set is captured from the same point in time. AWR stores the snapshot data for all instances in the same table and the data is identified by an instance qualifier. For example, the
BUFFER_BUSY_WAIT
statistic shows the number of buffer waits on each instance.
AWR does not store data that is aggregated from across the entire cluster. In other words, the data is stored for each individual instance.
Using the Automatic Database Diagnostic Monitor (ADDM), you can analyze the information collected by AWR for possible performance problems with Oracle
Database. ADDM presents performance data from a cluster-wide perspective, thus enabling you to analyze performance on a global basis. In an Oracle RAC environment, ADDM can analyze performance using data collected from all instances and present it at different levels of granularity, including:
• Analysis for the entire cluster
• Analysis for a specific database instance
• Analysis for a subset of database instances
To perform these analyses, you can run the ADDM Advisor in ADDM for Oracle RAC mode to perform an analysis of the entire cluster; in Local ADDM mode to analyze the performance of an individual instance; or in Partial ADDM mode to analyze a subset of instances. Activate ADDM analysis using the advisor framework through Advisor
Central in Oracle Enterprise Manager, or through the
DBMS_ADVISOR
and
DBMS_ADDM
PL/SQL packages.
Related Topics:
Oracle Database Performance Tuning Guide
Oracle Database PL/SQL Packages and Types Reference
Active Session History Reports for Oracle RAC
This section describes Active Session History (ASH) reports for Oracle RAC under the following topics:
•
Overview of ASH Reports for Oracle RAC
•
ASH Report for Oracle RAC: Top Cluster Events
•
ASH Report for Oracle RAC: Top Remote Instance
Monitoring Performance 14-7
Monitoring Oracle RAC Statistics and Wait Events
Related Topics:
Oracle Database Performance Tuning Guide
Overview of ASH Reports for Oracle RAC
ASH is an integral part of the Oracle Database self-management framework and is useful for diagnosing performance problems in Oracle RAC environments. ASH report statistics provide details about Oracle Database session activity. Oracle
Database records information about active sessions for all active Oracle RAC instances and stores this data in the System Global Area (SGA). Any session that is connected to the database and using CPU is considered an active session. The exception to this is sessions that are waiting for an event that belongs to the idle wait class.
ASH reports present a manageable set of data by capturing only information about active sessions. The amount of the data is directly related to the work being performed, rather than the number of sessions allowed on the system.
ASH statistics that are gathered over a specified duration can be put into ASH reports.
Each ASH report is divided into multiple sections to help you identify short-lived performance problems that do not appear in the ADDM analysis. Two ASH report sections that are specific to Oracle RAC are Top Cluster Events and Top Remote
Instance as described in the next two sections.
ASH Report for Oracle RAC: Top Cluster Events
The ASH report Top Cluster Events section is part of the Top Events report that is specific to Oracle RAC. The Top Cluster Events report lists events that account for the highest percentage of session activity in the cluster wait class event along with the instance number of the affected instances. You can use this information to identify which events and instances caused a high percentage of cluster wait events.
ASH Report for Oracle RAC: Top Remote Instance
The ASH report Top Remote Instance section is part of the Top Load Profile report that is specific to Oracle RAC. The Top Remote Instance report shows cluster wait events along with the instance numbers of the instances that accounted for the highest percentages of session activity. You can use this information to identify the instance that caused the extended cluster wait period.
Monitoring Oracle RAC Statistics and Wait Events
This section explains wait events and statistics specific to Oracle RAC and how to interpret them when assessing performance data generated by the Automatic
Workload Repository (AWR), Statspack, or by ad-hoc queries of the dynamic performance views.
This section includes the following topics:
•
Oracle RAC Statistics and Events in AWR and Statspack Reports
•
•
Monitoring Performance by Analyzing GCS and GES Statistics
•
Analyzing Cache Fusion Transfer Impact Using GCS Statistics
•
Analyzing Response Times Based on Wait Events
14-8 Oracle Real Application Clusters Administration and Deployment Guide
Monitoring Oracle RAC Statistics and Wait Events
Related Topics:
Oracle Database Performance Tuning Guide
Oracle Streams Concepts and Administration
Oracle RAC Statistics and Events in AWR and Statspack Reports
The statistics snapshots generated by AWR and Statspack can be evaluated by producing reports displaying summary data such as load and cluster profiles based on regular statistics and wait events gathered on each instance.
Most of the relevant data is summarized on the Oracle RAC Statistics Page. This information includes:
• Global cache load profile
• Global cache efficiency percentages—workload characteristics
• Global cache and Enqueue Service (GES)—messaging statistics
Additional Oracle RAC sections appear later in the report:
• Global enqueue statistics
• Global CR statistics
• Global
CURRENT
served statistics
• Global cache transfer statistics.
Oracle RAC Wait Events
Analyzing and interpreting what causes sessions to wait is an important method to determine where time is spent.
In Oracle RAC, the wait time is attributed to an event which reflects the exact outcome of a request. For example, when a session on an instance is looking for a block in the global cache, it does not know whether it will receive the data cached by another instance or whether it will receive a message to read from disk. The wait events for the global cache convey precise information and waiting for global cache blocks or messages is:
• Summarized in a broader category called Cluster Wait Class
• Temporarily represented by a placeholder event which is active while waiting for a block, for example:
– gc current block request
– gc cr block request
• Attributed to precise events when the outcome of the request is known, for example:
– gc current block 3-way
– gc current block busy
– gc cr block grant 2-way
Monitoring Performance 14-9
Monitoring Oracle RAC Statistics and Wait Events
In summary, the wait events for Oracle RAC convey information valuable for performance analysis. They are used in Automatic Database Diagnostic Monitor
(ADDM) to enable precise diagnostics of the effect of cache fusion.
Monitoring Performance by Analyzing GCS and GES Statistics
To determine the amount of work and cost related to inter-instance messaging and contention, examine block transfer rates, remote requests made by each transaction, the number and time waited for global cache events as described under the following headings:
•
Analyzing the Effect of Cache Fusion in Oracle RAC
•
Analyzing Performance Using GCS and GES Statistics
Analyzing the Effect of Cache Fusion in Oracle RAC
The effect of accessing blocks in the global cache and maintaining coherency is represented by:
• The Global Cache Service (GCS) statistics for current
and cr
blocks, for example, gc current blocks received
, gc cr blocks received
, and so on
• The GCS wait events, for gc current block 3-way
, gc cr grant 2-way
, and so on
The response time for cache fusion transfers is determined by the messaging and processing times imposed by the physical interconnect components, the IPC protocol and the GCS protocol. It is not affected by disk I/O factors other than occasional log writes. The cache fusion protocol does not require I/O to data files to guarantee
and Oracle RAC inherently does not cause any more I/O to disk than a
nonclustered instance.
Analyzing Performance Using GCS and GES Statistics
You can monitor GCS performance by identifying data blocks and objects which are frequently used (hot) by all instances.
High concurrency on certain blocks may be identified by GCS wait events and times.
The gc current block busy
wait event indicates that the access to cached data blocks was delayed because they were busy either in the remote or the local cache.
This could be caused by any of the following:
• The blocks were pinned
• The blocks were held up by sessions
• The blocks were delayed by a log write on a remote instance
• A session on the same instance was already accessing a block which was in transition between instances and the current session needed to wait behind it (for example, gc current block busy
)
Use the
V$SESSION_WAIT
view to identify objects and data blocks with contention.
The GCS wait events contain the file and block number for a block request in p1 and p2, respectively.
14-10 Oracle Real Application Clusters Administration and Deployment Guide
Monitoring Oracle RAC Statistics and Wait Events
An additional segment statistic, gc buffer busy
, has been added to quickly determine the busy objects without having to query the
V$SESSION_WAIT
view mentioned earlier.
The AWR infrastructure provides a view of active session history which can also be used to trace recent wait events and their arguments. It is therefore useful for hot block analysis. Most of the reporting facilities used by AWR and Statspack contain the object statistics and cluster wait class category, so that sampling of the views mentioned earlier is largely unnecessary.
Note:
Oracle recommends using ADDM and AWR. However, Statspack is available for backward compatibility. Statspack provides reporting only. You must run
Statspack at level 7 to collect statistics related to block contention and segment block waits.
It is advisable to run ADDM on the snapshot data collected by the AWR infrastructure to obtain an overall evaluation of the impact of the global cache. The advisory will also identify the busy objects and SQL highest cluster wait time.
Analyzing Cache Fusion Transfer Impact Using GCS Statistics
Describes how to monitor GCS performance by identifying objects read and modified frequently and the service times imposed by the remote access.
Waiting for blocks to arrive may constitute a significant portion of the response time, in the same way that reading from disk could increase the block access delays, only that cache fusion transfers are usually faster than disk access latencies.
The following wait events indicate that the remotely cached blocks were shipped to the local instance without having been busy, pinned or requiring a log flush:
• gc current block 2-way
• gc current block 3-way
• gc cr block 2-way
• gc cr block 3-way
The object statistics for gc current blocks received
and gc cr blocks received
enable quick identification of the indexes and tables which are shared by the active instances. As mentioned earlier, creating an ADDM analysis will usually point you to the SQL statements and database objects that could be impacted by interinstance contention.
Any increases in the average wait times for the events mentioned in the preceding list could be caused by the following occurrences:
• High load: CPU shortages, long run queues, scheduling delays
• Misconfiguration: using public instead of private interconnect for message and block traffic
If the average wait times are acceptable and no interconnect or load issues can be diagnosed, then the accumulated time waited can usually be attributed to a few SQL statements which need to be tuned to minimize the number of blocks accessed.
Monitoring Performance 14-11
Monitoring Oracle RAC Statistics and Wait Events
The column
CLUSTER_WAIT_TIME
in
V$SQLAREA
represents the wait time incurred by individual SQL statements for global cache events and will identify the SQL which may need to be tuned.
Analyzing Response Times Based on Wait Events
Most global cache wait events that show a high total time as reported in the AWR and
Statspack reports or in the dynamic performance views are normal and may present themselves as the top database time consumers without actually indicating a problem.
This section describes frequent wait events that you should be aware of when interpreting performance data.
If user response times increase and a high proportion of time waited is for global cache, then you should determine the cause. Most reports include a breakdown of events sorted by percentage of the total time.
It is useful to start with an ADDM report, which analyzes the routinely collected performance statistics with respect to their impact, and points to the objects and SQL contributing most to the time waited, and then moves on to the more detailed reports produced by AWR and Statspack.
Wait events for Oracle RAC include the following categories:
•
•
•
Contention-Related Wait Events
•
Block-Related Wait Events
The main wait events for block-related waits are:
• gc current block 2-way
• gc current block 3-way
• gc cr block 2-way
• gc cr block 3-way
The block-related wait event statistics indicate that a block was received as either the result of a 2-way or a 3-way message, that is, the block was sent from either the resource master requiring 1 message and 1 transfer, or was forwarded to a third node from which it was sent, requiring 2 messages and 1 block transfer.
Message-Related Wait Events
The main wait events for message-related waits are:
• gc current grant 2-way
• gc cr grant 2-way
The message-related wait event statistics indicate that no block was received because it was not cached in any instance. Instead a global grant was given, enabling the requesting instance to read the block from disk or modify it.
14-12 Oracle Real Application Clusters Administration and Deployment Guide
Monitoring Oracle RAC Statistics and Wait Events
If the time consumed by these events is high, then it may be assumed that the frequently used SQL causes a lot of disk I/O (in the event of the cr grant
) or that the workload inserts a lot of data and needs to find and format new blocks frequently
(in the event of the current grant).
Contention-Related Wait Events
The main wait events for contention-related waits are:
• gc current block busy
• gc cr block busy
• gc buffer busy acquire/release
The contention-related wait event statistics indicate that a block was received which was pinned by a session on another node, was deferred because a change had not yet been flushed to disk or because of high concurrency, and therefore could not be shipped immediately. A buffer may also be busy locally when a session has already initiated a cache fusion operation and is waiting for its completion when another session on the same node is trying to read or modify the same data. High service times for blocks exchanged in the global cache may exacerbate the contention, which can be caused by frequent concurrent read and write accesses to the same data.
The gc current block busy
and gc cr block busy
wait events indicate that the local instance that is making the request did not immediately receive a current or consistent read block. The term busy in these events' names indicates that the sending of the block was delayed on a remote instance. For example, a block cannot be shipped immediately if Oracle Database has not yet written the redo for the block's changes to a log file.
In comparison to block busy
wait events, a gc buffer busy
event indicates that
Oracle Database cannot immediately grant access to data that is stored in the local buffer cache. This is because a global operation on the buffer is pending and the operation has not yet completed. In other words, the buffer is busy and all other processes that are attempting to access the local buffer must wait to complete.
The existence of gc buffer busy
events also means that there is block contention that is resulting in multiple requests for access to the local block. Oracle Database must queue these requests. The length of time that Oracle Database needs to process the queue depends on the remaining service time for the block. The service time is affected by the processing time that any network latency adds, the processing time on the remote and local instances, and the length of the wait queue.
The average wait time and the total wait time should be considered when being alerted to performance issues where these particular waits have a high impact.
Usually, either interconnect or load issues or SQL execution against a large shared working set can be found to be the root cause.
Load-Related Wait Events
The main wait events for load-related waits are:
• gc current block congested
• gc cr block congested
The load-related wait events indicate that a delay in processing has occurred in the
GCS, which is usually caused by high load, CPU saturation and would have to be solved by additional CPUs, load-balancing, off loading processing to different times or
Monitoring Performance 14-13
Monitoring Oracle RAC Statistics and Wait Events a new cluster node.For the events mentioned, the wait time encompasses the entire round trip from the time a session starts to wait after initiating a block request until the block arrives.
14-14 Oracle Real Application Clusters Administration and Deployment Guide
15
Converting Single-Instance Oracle
Databases to Oracle RAC and Oracle RAC
One Node
Procedures for converting from Oracle Database single-instance databases to Oracle
Real Application Clusters (Oracle RAC) and Oracle RAC One Node databases.
The procedures in this chapter assume that your original single-instance database and the target Oracle RAC database are using the same release and running on the same platform. If you are upgrading from an earlier version of Oracle RAC to Oracle RAC
12c, then use Oracle Database Upgrade Assistant (DBUA).
This chapter includes the following topics:
•
Administrative Issues for Converting Databases to Oracle RAC
•
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
•
Preparing to Convert with rconfig and Oracle Enterprise Manager
•
Converting Databases to Oracle RAC Using rconfig
•
Example of rconfig XML Input Files for ConvertToRAC
•
Note:
You must use clustered Oracle Automatic Storage Management (Oracle ASM) instances for Oracle RAC databases.
Related Topics:
Oracle Database Licensing Information
Administrative Issues for Converting Databases to Oracle RAC
Note the following administrative considerations before converting single-instance databases to Oracle RAC:
• Backup procedures should be available before converting from a single-instance
Oracle Database to Oracle RAC. This includes taking a backup of your existing database before converting to Oracle RAC and being prepared to backup your
Oracle RAC database immediately following the conversion.
Converting Single-Instance Oracle Databases to Oracle RAC and Oracle RAC One Node 15-1
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
• For archiving with Oracle RAC environments, the archive file format requires a thread number.
• The archived logs from all instances of an Oracle RAC database are required for media recovery. Because of this requirement, if you archive to a file and you do not use a cluster file system, or some other means to provide shared file systems, then you require a method of accessing the archive logs from all nodes on which the cluster database has instances.
• By default, all database files are migrated to Oracle Managed Files. This feature simplifies tablespace creation, ensures data file location consistency and compliance with Oracle Flexible Architecture rules, and reduces human error with data file management.
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
You can use Database Configuration Assistant (DBCA) to convert from single-instance
Oracle databases to Oracle RAC or Oracle RAC One Node databases.
DBCA automates the configuration of the control file attributes, creates the undo tablespaces and the redo logs, and creates the initialization parameter file entries for cluster-enabled environments. DBCA also configures Oracle Net Services, Oracle
Clusterware resources, and the configuration for Oracle RAC database management using Oracle Enterprise Manager or the Server Control utility (SRVCTL).
Before you use DBCA to convert a single-instance database to an Oracle RAC or an
Oracle RAC One Node database, ensure that your system meets the following conditions:
• Your system uses supported hardware and operating system software. Your system is configured properly to support an Oracle RAC database.
• The nodes have access to shared storage; for example, either Oracle Cluster File
System or Oracle ASM is available and accessible from all nodes. On Linux on
POWER systems, ensure that GPFS is available and accessible from all nodes.
• Your applications have no design characteristics that preclude their use with cluster database processing.
If your platform supports a cluster file system, then you can use it for Oracle RAC.
You can also convert to Oracle RAC and use a non-shared file system. In either case,
Oracle strongly recommends that you use Oracle Universal Installer to install Oracle
Database 12c, which sets up the Oracle home and inventory in an identical location on each of the selected nodes in your cluster.
This section includes the following topics:
•
Converting Oracle Database Installations to Oracle RAC Using DBCA
•
Converting Single Instance on a Cluster to Oracle RAC One Node Using DBCA
•
Converting Single Instance on a Cluster to Oracle RAC Using DBCA
Related Topics:
15-2 Oracle Real Application Clusters Administration and Deployment Guide
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
Converting Oracle Database Installations to Oracle RAC Using DBCA
To convert from a single-instance Oracle Database that is on a non-clustered computer to Oracle RAC, perform the procedures described in the following sections, and in the order shown:
•
Use DBCA to Create an Image of the Single-Instance Database
•
Complete the Oracle Clusterware Installation
•
•
Copy the Preconfigured Database Image
•
Install Oracle Database 12c Software with Oracle RAC
Use DBCA to Create an Image of the Single-Instance Database
Use DBCA to create a preconfigured image of your single-instance database by using the following procedure:
1.
Navigate to the bin
directory in
$ORACLE_HOME
, and start DBCA.
2.
3.
4.
5.
6.
At the Welcome page, click Next.
On the Operations page, select Manage Templates, and click Next.
On the Template Management page, select Create a database template and From
an existing database (structure as well as data)
, then click Next.
On the Source Database page, select the database name in the Database instance list, and click Next.
Use SQL to ensure that all pluggable databases (PDBs) are open, as follows:
SQL> SELECT name, open_mode FROM v$pdbs;
7.
If any of the PDBs are in a state other than OPEN, then open them using SQL.
On the Template Properties page, enter a name for your template in the Name field. Oracle recommends that you use the database name.
By default, the template files are generated in the directory
$ORACLE_HOME/ assistants/dbca/templates
. You can enter a description of the file in the
Description field, and change the template file location in the Template data file field.
When you have completed the entries, click Next.
8.
On the Location of Database Related Files page, select Maintain the file locations, so that you can restore the database to the current directory structure, and click
Finish
.
DBCA generates two files: a database structure file (
template_name.dbc
), and a database preconfigured image file (
template_name.dfb
).
Complete the Oracle Clusterware Installation
Complete the installation of Oracle Clusterware.
Converting Single-Instance Oracle Databases to Oracle RAC and Oracle RAC One Node 15-3
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
Related Topics:
Oracle Grid Infrastructure Installation and Upgrade Guide
Validate the Cluster
Validate the cluster configuration using Cluster Verification Utility (CVU).
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Copy the Preconfigured Database Image
Copy the preconfigured database image. This includes copying the database structure
*.dbc
file and the database preconfigured image
*.dfb
file (that you used DBCA to create in a previous section) to a temporary location on the node in the cluster from which you plan to run DBCA.
Related Topics:
Use DBCA to Create an Image of the Single-Instance Database
Use DBCA to create a preconfigured image of your single-instance database by using the following procedure:
Install Oracle Database 12c Software with Oracle RAC
1.
Run Oracle Universal Installer to install an Oracle Database with Oracle RAC.
2.
3.
4.
5.
Select Cluster Installation Mode on the Specify Hardware Cluster Installation page of Oracle Universal Installer, and select the nodes to include in your Oracle
RAC database.
On the Oracle Universal Installer Database Configuration Types page, select the
Advanced
installation type.
After installing the Oracle Database software, Oracle Universal Installer runs postinstallation configuration tools, such as Net Configuration Assistant
(NETCA), DBCA, and so on.
On the DBCA Template Selection page, use the template that you copied to a temporary location in the previous section. Use the browse option to select the template location.
Select the option that you want to deploy. Your choices are the following: Oracle
RAC database; Oracle RAC One Node database; or Oracle single-instance database.
After creating the Oracle RAC database, DBCA displays the Password
Management page on which you must change the passwords for database users who have SYSDBA and SYSOPER privileges. When DBCA exits, the conversion process is complete.
Converting Single Instance on a Cluster to Oracle RAC One Node Using DBCA
Use DBCA to convert a single-instance Oracle Database to Oracle RAC One Node by using the following procedure:
1.
Change directory to
$ORACLE_HOME/bin
.
15-4 Oracle Real Application Clusters Administration and Deployment Guide
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
2.
3.
4.
Start DBCA:
$ dbca
From the Welcome window, select Oracle RAC One Node database.
Use the template that you selected to deploy in the previous section.
Converting Single Instance on a Cluster to Oracle RAC Using DBCA
There are three scenarios in which a single-instance database can exist on a cluster node:
• Scenario 1: The Oracle home for the single-instance database was installed on a cluster node and has Oracle RAC enabled.
• Scenario 2: The Oracle home for the single-instance database was installed on a cluster node, but the Oracle RAC feature is disabled for this Oracle home.
• Scenario 3: The Oracle home for the single-instance database was installed on only the local node in a cluster. This happens when you select the Local Installation option on the Oracle Universal Installer Specify Hardware Cluster Installation page during the Oracle Database 12c installation.
Related Topics:
Single-Instance Database on a Cluster Running from an Oracle RAC-Enabled
Single-Instance Database on a Cluster Running from an Oracle RAC-Disabled
Converting Oracle Database Installations to Oracle RAC Using DBCA
Install Oracle Database 12c Software with Oracle RAC
Single-Instance Database on a Cluster Running from an Oracle RAC-Enabled Home
Perform the following procedures to convert a single-instance database on a cluster node running from an Oracle home that has the Oracle RAC option enabled.
1.
Use DBCA to create a preconfigured image of your single-instance database. To perform the conversion manually, shut down the single-instance database.
2.
3.
4.
5.
Add nodes to your cluster. Ensure that all nodes can access the shared storage used by Oracle Clusterware and Oracle RAC.
From the existing Oracle home, extend this home to the new nodes.
From a newly added node, configure the listeners on the additional nodes using
NETCA. Choose the same port number and protocol that you used on the existing node. If NETCA displays the existing node in the node list page, then do not select this node, because the listener is already configured on it.
Convert the database using one of the following procedures:
•
Automated Conversion Procedure Using DBCA
•
Converting Single-Instance Oracle Databases to Oracle RAC and Oracle RAC One Node 15-5
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
Related Topics:
Use DBCA to Create an Image of the Single-Instance Database
Use DBCA to create a preconfigured image of your single-instance database by using the following procedure:
Oracle Clusterware Administration and Deployment Guide
Adding Oracle RAC to Nodes with Oracle Clusterware Installed
Automated Conversion Procedure Using DBCA
If you used DBCA to create a preconfigured image of your single-instance database as described in a previous section, then perform the following steps to complete the conversion to an Oracle RAC database:
1.
Start DBCA from the initial node. Select the names of the nodes to include as part of your cluster database. On the Template Selection page, select the preconfigured template that you created. Enter the database name and respond to the remaining
DBCA prompts.
2.
Specify the shared storage location for the Oracle Database data files. To use raw devices for the data files, you cannot use DBCA.
After creating the Oracle RAC database, DBCA displays the Password Management page on which you must change the passwords for the database users who have
SYSDBA and SYSOPER privileges. When DBCA exits, the conversion process is complete.
Related Topics:
Use DBCA to Create an Image of the Single-Instance Database
Use DBCA to create a preconfigured image of your single-instance database by using the following procedure:
Manual Conversion Procedure
If you did not use DBCA to create a preconfigured image of your single-instance database as described in a previous section, then perform the following steps to complete the conversion:
1.
2.
Create the Optimal Flexible Architecture directory structure on each of the nodes that you have added.
Re-create the control files by running the
CREATE CONTROLFILE
SQL statement with the
REUSE
keyword and specify
MAXINSTANCES
and
MAXLOGFILES
, and so on, as needed for your Oracle RAC configuration. The
MAXINSTANCES recommended default is 32.
3.
4.
Shut down the database instance.
If your single-instance database was using an SPFILE, then create a temporary parameter file (PFILE) from the SPFILE using the following SQL statement:
CREATE PFILE='pfile_name' from spfile='spfile_name'
15-6 Oracle Real Application Clusters Administration and Deployment Guide
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
5.
6.
7.
8.
9.
Set the
CLUSTER_DATABASE
parameter to
TRUE
, and set the
INSTANCE_NUMBER parameter to a unique value for each instance, using the
sid.parameter=value syntax.
If you optimized memory usage on your single-instance database, then adjust the size of the system global area (SGA) to avoid swapping and paging when you convert to Oracle RAC. You should make this adjustment because Oracle RAC requires about 350 bytes for each buffer to accommodate the Global Cache Service
(GCS). For example, if you have 10,000 buffers, then Oracle RAC requires approximately 350 multiplied by 10,000 bytes more memory. Therefore, adjust the size of the SGA by changing the
DB_CACHE_SIZE
and
DB_nK_CACHE_SIZE parameters accordingly.
Start the database instance using the PFILE created in Step 4 .
If your single-instance database was using automatic undo management, then create an undo tablespace for each additional instance using the
CREATE UNDO
TABLESPACE
SQL statement.
Create redo threads that have at least two redo logs for each additional instance.
Enable the new redo threads by using an
ALTER DATABASE
SQL statement. Then, shut down the database instance.
Copy the Oracle password file from the initial node, or from the node on which you are working, to the corresponding location on the additional nodes on which the cluster database will have an instance. Replace the
ORACLE_SID
name in each password file appropriately for each additional instance.
10.
Set the
REMOTE_LISTENER
parameter to the single client access name (SCAN) and port.
11.
Configure the net service entries for the database and instances, and address entries for the
LOCAL_LISTENER
for each instance and for the
REMOTE_LISTENER
in the tnsnames.ora
file, and copy the tnsnames.ora
file to all nodes.
12.
Create the SPFILE from the PFILE.
13.
Create the
$ORACLE_HOME/dbs/initsid.ora
file that contains the following entry, where
spfile_path_name
is the complete path name of the SPFILE: spfile='spfile_path_name'
14.
On the local node, use SQL*Plus to run catclust.sql
. This script creates the dictionary views needed for Oracle RAC databases. For example:
SQL> start ?/rdbms/admin/catclust.sql
15.
Add the configuration for the Oracle RAC or Oracle RAC One Node database and its instance-to-node mapping using SRVCTL.
a.
To add the configuration of an Oracle RAC database, use the following commands:
$ srvctl add database -dbname db_name -oraclehome Oracle_home -spfile
spfile_path_name
$ srvctl add instance -dbname db_name -instance inst1_name -node node1_name
$ srvctl add instance -dbname db_name -instance inst2_name -node node2_name
...
Converting Single-Instance Oracle Databases to Oracle RAC and Oracle RAC One Node 15-7
Converting to Oracle RAC and Oracle RAC One Node Using DBCA
b.
To add the configuration of an Oracle RAC One Node database, use the following command:
$ srvctl add database -dbname db_name -dbtype RACONENODE -oraclehome
Oracle_home
-spfile spfile_path_name
16.
Start the Oracle RAC or Oracle RAC One Node database using SRVCTL: srvctl start database -d db_name
After starting the database with SRVCTL, your conversion process is complete. You can run the following SQL statement to see the status of all the instances in your
Oracle RAC database:
SQL> SELECT * FROM v$active_instances;
Related Topics:
Use DBCA to Create an Image of the Single-Instance Database
Use DBCA to create a preconfigured image of your single-instance database by using the following procedure:
Oracle Real Application Clusters Installation Guide
Single-Instance Database on a Cluster Running from an Oracle RAC-Disabled Home
You can create a single-instance database on a cluster running from an Oracle home with the Oracle RAC option disabled. To create an Oracle home on a cluster with
Oracle RAC disabled, you can select local and non-cluster on the Node Selection Page of Oracle Universal Installer when installing the Oracle Database software. You can also performed a one-node cluster (with Oracle RAC) installation, but later disable the
Oracle RAC option.
Perform the following procedures to convert this type of single-instance database to an
Oracle RAC or Oracle RAC One Node database:
1.
2.
3.
Use DBCA to create a preconfigured image of your single-instance database as described in a previous section. To perform the conversion manually, shut down the single-instance database.
Change the directory to the lib
subdirectory in the rdbms
directory under the
Oracle home.
Relink the oracle
binary by running the following commands: make -f ins_rdbms.mk rac_on make -f ins_rdbms.mk ioracle
4.
Add nodes to your cluster. Ensure that all nodes can access the shared storage used by Oracle Clusterware and Oracle RAC.
Related Topics:
Use DBCA to Create an Image of the Single-Instance Database
Use DBCA to create a preconfigured image of your single-instance database by using the following procedure:
Oracle Clusterware Administration and Deployment Guide
15-8 Oracle Real Application Clusters Administration and Deployment Guide
Preparing to Convert with rconfig and Oracle Enterprise Manager
Preparing to Convert with rconfig and Oracle Enterprise Manager
You can use rconfig
, or Oracle Enterprise Manager to assist with converting a single-instance database installation to an Oracle RAC database. The first of these, rconfig
, is a command-line utility. Oracle Enterprise Manager Cloud Control database administration option, Convert to Cluster Database, provides a GUI-based conversion tool. The following sections describe how to use these conversion tools:
•
Prerequisites for Converting to Oracle RAC Databases
•
Configuration Changes During Oracle RAC Conversion Using rconfig
•
Converting Databases to Oracle RAC Using rconfig or Oracle Enterprise Manager
•
Converting Databases to Oracle RAC Using Oracle Enterprise Manager
Note:
Before you start the conversion, back up your existing database; you should take a backup of your database before starting any major change.
Prerequisites for Converting to Oracle RAC Databases
Before you convert a single-instance database to an Oracle RAC database, ensure that the following conditions are met for each cluster node that you intend to make an
Oracle RAC database node:
• Oracle Clusterware 12c is installed, configured, and running.
• Oracle RAC 12c software is installed.
• The Oracle software has the Oracle RAC option enabled.
• Shared storage, either Oracle Cluster File System or Oracle ASM, is available and accessible from all nodes.
• User equivalence exists for the oracle
account, or the user account used to install the Oracle software.
• If you intend to use Oracle Enterprise Manager, then the Oracle Management
Agent on each node is configured and running, and is configured with cluster and host information.
• You have backed up your existing database.
Note:
You must use clustered Oracle ASM instances for Oracle RAC databases.
Configuration Changes During Oracle RAC Conversion Using rconfig
The following changes occur when you convert a single-instance database to Oracle
RAC using the rconfig
utility:
Converting Single-Instance Oracle Databases to Oracle RAC and Oracle RAC One Node 15-9
Preparing to Convert with rconfig and Oracle Enterprise Manager
• During the conversion, rconfig
places the target Oracle RAC database into archive log mode, and enables archiving for the database. If you do not plan to use archive log space, then you can disable archive logging after the conversion has completed.
• For the Shared Storage Type value, if you enter CFS, and you use a cluster file system for your single-instance database storage, then rconfig
converts the environment to use Oracle Managed Files for database storage, and places the data files in a subdirectory located under the shared storage location.
• During the conversion, rconfig
moves database files to a specified shared location, and configures them using Oracle Managed Files.
To avoid using Oracle Managed Files with your converted database, the singleinstance database files must be located in a shared file system, and you must indicate that rconfig
should not move the files.
Converting Databases to Oracle RAC Using rconfig or Oracle Enterprise Manager
The following list describes scenarios for converting a single-instance Oracle database to an Oracle RAC database:
• Converting a single-instance Oracle Database 12c database to an Oracle RAC 12c database, running out of the same Oracle home and using the same data files as the single-instance database.
In this scenario, run the rconfig
utility from the Oracle RAC database home, or use the Convert to RAC option on the single-instance database target of Oracle
Enterprise Manager Cloud Control.
• Converting a single-instance database that uses a release of Oracle Database earlier than Oracle Database 12c to an Oracle RAC 12c database, running out of the same Oracle home and using the same data files as the single-instance database
In this scenario, use Oracle Universal Installer and Database Upgrade Assistant
(DBUA) to update the single-instance database to Oracle Database 12c. Then use rconfig
or the Oracle Enterprise Manager Convert to RAC option, as described in the preceding scenario.
• Converting a single-instance Oracle Database 12c to an Oracle RAC 12c database, running out of a different Oracle home and using the same data files as the singleinstance database.
In this scenario, run the rconfig
utility in the target database home, or use the
Convert to RAC
option in the single-instance database target of Oracle Enterprise
Manager Cloud Control. Provide the file storage location when prompted.
Note:
If you specify Oracle home users for both the target database home and the source database home, then the Oracle home user for the target database home must be the same as the Oracle home user for the source database home.
• Converting a single-instance Oracle Database 12c to an Oracle RAC 12c database, running out of a different Oracle home, and where the host on which the singleinstance database runs is not a node used by the Oracle RAC database.
15-10 Oracle Real Application Clusters Administration and Deployment Guide
Preparing to Convert with rconfig and Oracle Enterprise Manager
In this scenario, create a clone image of the single-instance database, and move the clone image to a host that is one of the nodes used by the Oracle RAC database.
Then use rconfig
or the Oracle Enterprise Manager Convert to RAC option, as described in the preceding scenario.
Converting Databases to Oracle RAC Using Oracle Enterprise Manager
You can use Oracle Enterprise Manager Cloud Control to convert a single-instance database to an Oracle RAC database.
To use this feature, complete the following steps:
1.
Log in to Oracle Enterprise Manager Cloud Control. From the Home page, click the Targets tab.
2.
3.
4.
5.
6.
7.
8.
On the Targets page, click the Databases secondary tab, and click the link in the
Names column of the database to convert to Oracle RAC.
On the Database home page, from the Availability menu, select Convert to
Cluster Database
.
Log in as the database user
SYS
with
SYSDBA
privileges to the database you want to convert, and click Next.
On the Convert to Cluster Database: Cluster Credentials page, provide a user name and password for the oracle
user and password of the target database to convert. If the target database is using Oracle ASM, then also provide the
SYSASM user and password, and then click Next.
On the Hosts page, select the host nodes in the cluster to be cluster members in the installed Oracle RAC database. When you have completed your selection, click Next.
On the Convert to Database: Options page, select whether you want to use the existing listener and port number, or specify a new listener and port number for the cluster. Also provide a prefix for cluster database instances on the cluster.
When you have finished entering information, click Next, or click Help if you need assistance in deciding how to enter information.
On the Convert to Cluster Database: Shared Storage page, either select the option to use your existing shared storage area, or select the option to have your database files copied to a new shared storage location. Also, decide if you want to use your existing fast recovery area or copy your recovery files to a new fast recovery area using files managed by Oracle Database.
If you use Oracle ASM, then Oracle recommends that you place the data files and the recovery files in separate failure groups. A failure group is defined by shared hardware, such as a controller shared between two disks, or two disks that are on the same spindle. If two disks share hardware that could fail, making both disks unavailable, then theses disks are said to be in the same failure group. If you do not use Oracle ASM, then Oracle recommends that the data files and the recovery files are stored in separate locations, for example, separate Oracle ASM failure groups, so that a hardware failure does not affect availability.
When you have finished entering information, click Next, or click Help if you need assistance in deciding how to enter information.
Converting Single-Instance Oracle Databases to Oracle RAC and Oracle RAC One Node 15-11
Converting Databases to Oracle RAC Using rconfig
9.
On the Convert to Cluster Database: Review page, review the options you have selected. Click Submit Job to proceed with the conversion. To change any options you have selected, click Back. To cancel the conversion, click Cancel.
10.
On the Confirmation page, click View Job to check the status of the conversion.
Related Topics:
Oracle Database Upgrade Guide
Converting Databases to Oracle RAC Using rconfig
You can use the command-line utility rconfig
to convert a single-instance database to an Oracle RAC database, or to convert it to an Oracle RAC One Node database, depending on the values you provide in the
ConvertToRAC.xml
file. To use this feature, complete the following steps:
1.
2.
As the oracle
user, navigate to the directory
$ORACLE_HOME/assistants/ rconfig/sampleXMLs
, and open the file
ConvertToRAC.xml
using a text editor, such as vi
.
Review the
ConvertToRAC.xml
file, and modify the parameters as required for your system. The XML sample file contains comments that provide instructions for how to configure the file.
Caution:
Set the convert option
Convert verify="ONLY"
to perform a test conversion to ensure that a conversion can be completed successfully.
3.
When you have finished modifying parameters, save the file with a name of the format
file_name.xml
. Make a note of the name you select.
Navigate to the directory
$ORACLE_HOME/bin
, and use the following command to run the command rconfig
, where
input.xml
is the name of the XML input file you configured in Step
: rconfig input.xml
For example, if you create an input XML file called convert.xml
, then you would use the following command
$ ./rconfig convert.xml
15-12 Oracle Real Application Clusters Administration and Deployment Guide
Example of rconfig XML Input Files for ConvertToRAC
Note:
The
Convert verify
option in the
ConvertToRAC.xml
file has three options:
•
Convert verify="YES"
: rconfig performs checks to ensure that the prerequisites for single-instance to Oracle RAC conversion have been met before it starts conversion
•
Convert verify="NO"
: rconfig does not perform prerequisite checks, and starts conversion
•
Convert verify="ONLY"
rconfig only performs prerequisite checks; it does not start conversion after completing prerequisite checks
If performing the conversion fails, then use the following procedure to recover and reattempt the conversion.:
1.
2.
Attempt to delete the database using the DBCA delete database option.
Restore the source database.
3.
4.
Review the conversion log, and fix any problems reported by rconfig
that may have caused the conversion failure. The rconfig
log files are under the rconfig directory in
$ORACLE_BASE/cfgtoollogs
.
Reattempt the conversion.
Related Topics:
Oracle Database Upgrade Guide
Example of rconfig XML Input Files for ConvertToRAC
The following are two examples of an XML
ConvertToRAC
input file for the rconfig
utility.
Example 15-1 is an XML input file to convert a single-instance
database with Oracle ASM to a policy-managed Oracle RAC database (using server
pools) on Oracle ASM storage. Example 15-2 is an XML input file to convert a single-
instance database with Oracle ASM to an administrator-managed Oracle RAC database.
Example 15-1 Example rconfig ConvertToRAC XML File for Policy-Managed
Databases
<?xml version="1.0" encoding="UTF-8"?>
<n:RConfig xmlns:n="http://www.example.com/rconfig"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.example.com/rconfig">
<n:ConvertToRAC>
<!-- Verify does a precheck to ensure all pre-requisites are met, before the
conversion is attempted. Allowable values are: YES|NO|ONLY -->
<n:Convert verify="YES">
<!--Specify current OracleHome of non-rac database for SourceDBHome -->
<n:SourceDBHome>/oracle/product/12.1.0/db_1</n:SourceDBHome>
<!--Specify OracleHome where the rac database should be configured. It can be same
as SourceDBHome -->
<n:TargetDBHome>/oracle/product/12.1.0/db_1</n:TargetDBHome>
<!--Specify SID of non-rac database and credential. User with sysdba role is
Converting Single-Instance Oracle Databases to Oracle RAC and Oracle RAC One Node 15-13
Example of rconfig XML Input Files for ConvertToRAC
required to perform conversion -->
<n:SourceDBInfo SID="sales">
<n:Credentials>
<n:User>sys</n:User>
<n:Password>oracle</n:Password>
<n:Role>sysdba</n:Role>
</n:Credentials>
</n:SourceDBInfo>
<!--Specify the list of existing or new server pools which are used by the
Policy Managed Cluster Database. -->
<n:ServerPoolList>
<n:ExistingServerPool name="custom"/>
<n:NewServerPool name="newpool" cardinality="2"/>
</n:ServerPoolList>
<!--Specify RacOneNode along with servicename to convert database to RACOne
Node -->
<!--n:RacOneNode servicename="salesrac1service"/-->
<!--InstancePrefix is not required for Policy Managed database. If specified, it
will be ignored. Instance names are generated automatically based on db_unique_ name for Policy Managed dababase.-->
<!-- Listener details are no longer needed starting 11.2. Database is registered
with default listener and SCAN listener running from Oracle Grid Infrastructure
home. -->
<!--Specify the type of storage to be used by rac database. Allowable values are
CFS|ASM. The non-rac database should have same storage type. ASM credentials are
no needed for conversion. -->
<n:SharedStorage type="ASM">
<!--Specify Database Area Location to be configured for rac database.If this field
is left empty, current storage will be used for rac database. For CFS, this field
will have directory path. -->
<n:TargetDatabaseArea>+ASMDG</n:TargetDatabaseArea>
<!--Specify Fast Recovery Area to be configured for rac database. If this field is
left empty, current recovery area of non-rac database will be configured for rac
database. If current database is not using recovery Area, the resulting rac
database will not have a recovery area. -->
<n:TargetFlashRecoveryArea>+ASMDG</n:TargetFlashRecoveryArea>
</n:SharedStorage>
</n:Convert>
</n:ConvertToRAC>
</n:RConfig>
Example 15-2 Example rconfig ConvertToRAC XML File for Administrator-Managed
Databases
<?xml version="1.0" encoding="UTF-8"?>
<n:RConfig xmlns:n="http://www.example.com/rconfig"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.example.com/rconfig rconfig.xsd">
<n:ConvertToRAC>
<!-- Verify does a precheck to ensure all pre-requisites are met, before the
conversion is attempted. Allowable values are: YES|NO|ONLY -->
<n:Convert verify="YES">
<!--Specify current OracleHome of non-rac database for SourceDBHome -->
<n:SourceDBHome>/oracle/product/12.1.0/db_1</n:SourceDBHome>
<!--Specify OracleHome where the rac database should be configured. It can be same
as SourceDBHome -->
<n:TargetDBHome>/oracle/product/12.1.0/db_1</n:TargetDBHome>
<!--Specify SID of non-rac database and credential. User with sysdba role is
required to perform conversion -->
<n:SourceDBInfo SID="sales">
<n:Credentials>
15-14 Oracle Real Application Clusters Administration and Deployment Guide
Postconversion Steps
<n:User>sys</n:User>
<n:Password>oracle</n:Password>
<n:Role>sysdba</n:Role>
</n:Credentials>
</n:SourceDBInfo>
<!--Specify the list of nodes that should have rac instances running for the Admin
Managed Cluster Database. LocalNode should be the first node in this nodelist.
-->
<n:NodeList>
<n:Node name="node1"/>
<n:Node name="node2"/>
</n:NodeList>
<!--Specify RacOneNode along with servicename to convert database to RACOne
Node -->
<!--n:RacOneNode servicename="salesrac1service"/-->
<!--Instance Prefix tag is optional starting with 11.2. If left empty, it is
derived from db_unique_name.-->
<n:InstancePrefix>sales</n:InstancePrefix>
<!-- Listener details are no longer needed starting 11.2. Database is registered
with default listener and SCAN listener running from Oracle Grid Infrastructure
home. -->
<!--Specify the type of storage to be used by rac database. Allowable values are
CFS|ASM. The non-rac database should have same storage type. ASM credentials are not needed for conversion. -->
<n:SharedStorage type="ASM">
<!--Specify Database Area Location to be configured for rac database.If this field
is left empty, current storage will be used for rac database. For CFS, this field will have directory path. -->
<n:TargetDatabaseArea>+ASMDG</n:TargetDatabaseArea>
<!--Specify Fast Recovery Area to be configured for rac database. If this field is
left empty, current recovery area of non-rac database will be configured for rac
database. If current database is not using recovery Area, the resulting rac
database will not have a recovery area. -->
<n:TargetFlashRecoveryArea>+ASMDG</n:TargetFlashRecoveryArea>
</n:SharedStorage>
</n:Convert>
</n:ConvertToRAC>
</n:RConfig>
Postconversion Steps
After completing the conversion, note the following recommendations for Oracle RAC environments, as described in the following:
• Follow the recommendations for using load balancing and transparent application failover, as previously described
• Use locally managed tablespaces instead of dictionary managed tablespaces to reduce contention and manage sequences in Oracle RAC as described in Oracle
Database Administrator’s Guide
• Follow the guidelines for using automatic segment space management as described in Oracle Database Administrator’s Guide
The buffer cache and shared pool capacity requirements in Oracle RAC are slightly greater than the requirements for single-instance Oracle databases. Therefore, you should increase the size of the buffer cache by about 10%, and the size of the shared pool by about 15%.
Converting Single-Instance Oracle Databases to Oracle RAC and Oracle RAC One Node 15-15
Postconversion Steps
Related Topics:
Workload Management with Dynamic Database Services
Workload management includes load balancing, enabling clients for
Oracle Real Application Clusters (Oracle RAC), distributed transaction processing, and services.
Oracle Database Administrator’s Guide
Oracle Database Administrator’s Guide
15-16 Oracle Real Application Clusters Administration and Deployment Guide
A
Server Control Utility Reference
Use the Server Control Utility (SRVCTL) to manage Oracle Real Application Clusters
(Oracle RAC) configuration information.
This appendix includes the following topics:
•
•
Specifying Command Parameters as Keywords Instead of Single Letters
•
Character Set and Case Sensitivity of SRVCTL Object Values
•
Summary of Tasks for Which SRVCTL Is Used
•
•
SRVCTL Privileges and Security
•
•
Deprecated SRVCTL Subprograms or Commands
•
SRVCTL Usage Information
SRVCTL is installed on each node in a cluster by default. To use SRVCTL, log in to the operating system of a node and enter the SRVCTL command and its parameters in case-sensitive syntax.
• Only use the version of SRVCTL that is provided with Oracle Database 12c on
Oracle RAC databases that are created for or upgraded to Oracle Database 12c.
The version of SRVCTL must be the same as the version of the object (listeners,
Oracle ASM instances, Oracle RAC databases and their instances, and services) being managed. To ensure the versions are the same release, run SRVCTL commands from the Oracle home of the database or object you are managing.
• SRVCTL does not support concurrent executions of commands on the same object. Therefore, run only one SRVCTL command at a time for each database, service, or other object.
• When specifying a comma-delimited list as part of a SRVCTL command, there should not be any spaces between the items in the list. For example: srvctl add database -serverpool "serverpool1,serverpool3"
When you specify a comma-delimited list in a Windows environment, you must enclose the list in double quotation marks (
""
). You can enclose a commadelimited list in double quotation marks in a Linux or UNIX environment but they will be ignored.
Server Control Utility Reference A-1
Specifying Command Parameters as Keywords Instead of Single Letters
• If you are entering a SRVCTL command, and you want to continue the input on a new line, then you can use the operating system continuation character. In Linux, this is the backslash (\) symbol.
• A SRVCTL command that produces no output is a successful command. Not all
SRVCTL commands return a message when it completes, successfully. However, if a SRVCTL command fails, then it always returns an error message.
• You can use the
-eval
parameter with several SRVCTL commands. This parameter, when you use it, enables you to simulate running a command without making any changes to the system. SRVCTL returns output that informs you what will happen if you run a particular command. For example, to know what might happen if you relocate a server:
$ srvctl relocate server –servers "rac1" –eval –serverpool pool2
Database db1
will stop on node rac1
will start on node rac7
Service mySrv1
will stop on node rac1, it will not run on any node
Service myServ2
will stop on node rac1
will start on node rac6
Server rac1
will be moved from pool myPoolX to pool pool2
The
-eval
parameter is available with the following commands:
– srvctl add database
– srvctl add service
– srvctl add srvpool
– srvctl modify database
– srvctl modify service
– srvctl modify srvpool
– srvctl relocate server
– srvctl relocate service
– srvctl remove srvpool
– srvctl start database
– srvctl start service
– srvctl stop database
– srvctl stop service
Specifying Command Parameters as Keywords Instead of Single Letters
Before Oracle Database 12c, the SRVCTL command-line interface used single letter parameters. However, this imposes a limit on the number of unique parameters available for use with SRVCTL commands. SRVCTL command parameters introduced
A-2 Oracle Real Application Clusters Administration and Deployment Guide
Character Set and Case Sensitivity of SRVCTL Object Values in Oracle Database 12c are full words instead of single letters, such as
multicastport
and
-subdomain
.
To support backward compatibility, you can use a mix of single-letter parameters and new keyword parameters. New parameters introduced with keywords can be used with single letter parameters.
Note:
Starting with Oracle Database 12c, the single letter parameters are deprecated in favor of the keyword parameters to avoid using the same letter to implement different functionality depending on the command.
You can obtain the single-letter equivalents, where applicable, by adding the
compatible
parameter after the
-help
parameter.
Character Set and Case Sensitivity of SRVCTL Object Values
SRVCTL interacts with many different types of objects. The character set and name length limitations, and whether the object name is case sensitive, can vary between object types.
Table A-1 String Restrictions for SRVCTL Object Names
Object Type
db_domain db_unique_nam e
Character Set Limitations Case
Sensitive?
Alpha-numeric characters, underscore (_), and number sign
(#)
Alpha-numeric characters, underscore (_), number sign (#), and dollar sign ($); the first 8 characters must be unique because those characters are used to form instance names for policy-managed databases
No diskgroup_nam e instance_name
Naming disk groups have the same limitations as naming other database objects.
See Also:
Oracle Database SQL
Language Reference
for more information about database object naming rules
Alpha-numeric characters
No (all names are converted to uppercase)
Depends on the platform
Maximum Length
128 characters
30 characters but the first 8 characters must be unique relative to any other database in the same cluster
15 characters listener_name
No node_name
Server Control Utility Reference A-3
Summary of Tasks for Which SRVCTL Is Used
Table A-1 (Cont.) String Restrictions for SRVCTL Object Names
Object Type Character Set Limitations Maximum Length Case
Sensitive?
No scan_name
The first character must be an alphabetic character server_pool
Alpha-numeric characters, underscore (_), number sign (#), period (.), and dollar sign ($); the name cannot begin with a period, contain single quotation marks (
''
), nor can the name be
"Generic" or "Free" because those two names are reserved for the built-in server pools
250 characters
250 characters service_name volume_name
Alphanumeric characters; dashes (-) are not allowed and the first character must be an alphabetic character.
No 11 characters
Summary of Tasks for Which SRVCTL Is Used
Use SRVCTL to manage databases, instances, cluster databases, cluster database instances, Oracle ASM instances and disk groups, services, listeners, or other clusterware resources.
• Cluster Database Configuration Tasks
Tasks
Add, modify, and delete cluster database configuration information
Add an instance to or delete an instance from the configuration of a cluster database
Add a service to or delete a service from the configuration of a cluster database
Commands
srvctl add database srvctl modify database srvctl remove database srvctl add instance srvctl remove instance srvctl add service srvctl remove service
Move instances and services in a cluster database configuration and modify service configurations srvctl relocate database srvctl relocate service srvctl modify instance srvctl modify service
A-4 Oracle Real Application Clusters Administration and Deployment Guide
Summary of Tasks for Which SRVCTL Is Used
Tasks
Set and unset the environment for an instance or service in a cluster database configuration
Set and unset the environment for an entire cluster database in a cluster database configuration
Commands
srvctl modify instance srvctl modify service srvctl setenv database srvctl unsetenv database
• General Cluster Database Administration Tasks
Tasks
Start and stop cluster databases
Commands
srvctl start database srvctl stop database
Start and stop cluster database instances srvctl start instance srvctl stop instance
Start, stop, and relocate cluster database services srvctl start service srvctl stop service srvctl relocate service
Obtain statuses of cluster databases, cluster database instances, or cluster database services srvctl status database srvctl status instance srvctl status service
• Node-Level Tasks
Tasks
Administering VIPs
Commands
srvctl add vip srvctl config vip srvctl disable vip srvctl enable vip srvctl getenv vip srvctl modify vip srvctl relocate vip srvctl remove vip srvctl setenv vip srvctl start vip srvctl status vip srvctl stop vip srvctl unsetenv vip
Server Control Utility Reference A-5
Using SRVCTL Help
Tasks
Administering node applications
Commands
srvctl add nodeapps srvctl disable nodeapps srvctl enable nodeapps srvctl getenv nodeapps srvctl modify nodeapps srvctl remove nodeapps srvctl setenv nodeapps srvctl unsetenv nodeapps
Related Topics:
Oracle Clusterware Administration and Deployment Guide
Using SRVCTL Help
This section includes information about using context sensitive help with SRVCTL.
To see help for all SRVCTL commands, from the command line enter: srvctl -help
To see the command syntax and a list of parameters for each SRVCTL command, from the command line enter: srvctl command (or verb) object (or noun) -help
When you request online help for a command using
-help
, SRVCTL prints the full words for each parameter. You can obtain the single-letter equivalents, where applicable, by adding the
-compatible
parameter after the
-help
parameter. For example:
$ srvctl config database -help -compatible
The preceding command prints usage information for the srvctl config database
command, listing all parameters as full words followed by their singleletter equivalents in parentheses, where applicable.
To see the SRVCTL version number enter:
$ srvctl -version
SRVCTL Privileges and Security
To use SRVCTL to change your Oracle RAC database configuration, log in to the operating system as the software owner of the home that you want to manage.
For example, if different users installed Oracle Database and the Oracle Grid
Infrastructure, then log in as the database software owner (for example, ora_db
) to manage databases and log in as the Oracle Grid Infrastructure software owner (for example, ora_asm
) to manage the Oracle ASM instances.
Users who are members of the OSDBA operating system group can start and stop the database. To stop and start an Oracle ASM instance, you must be a member of the
OSASM operating system group.
To create or register objects such as listeners, Oracle Notification Services, and services, you must be logged in to the operating system as the software owner of the
A-6 Oracle Real Application Clusters Administration and Deployment Guide
Additional SRVCTL Topics
Oracle home. The objects you create or register for that Oracle home will run under the user account of the owner of the Oracle home. Databases run as the database installation owner of the home from which they run.
To perform srvctl add
operations on any object, you must be logged in as the
Oracle account owner of the home on which the object runs.
For some SRVCTL commands, on Linux and UNIX systems, you must be logged in as root
, and on Windows systems, you must be logged in as a user with Administrator privileges to run them. In this appendix, those commands are preceded by the root prompt (#) in the command examples.
Additional SRVCTL Topics
• Use SRVCTL to manage Oracle-supplied resources such as listener, instances, disk groups, and networks, and CRSCTL for managing Oracle Clusterware and its resources.
Note:
Oracle strongly discourages directly manipulating Oracle-supplied resources
(resources whose names begin with ora) using CRSCTL. This could adversely impact the cluster configuration.
• Although you may be able to cancel running SRVCTL commands by pressing the
Control-C keys, you may corrupt your configuration data by doing this.
You are strongly advised not to attempt to terminate SRVCTL in this manner.
Deprecated SRVCTL Subprograms or Commands
A number of SRVCTL commands and parameters have been deprecated in this release.
Single Character Parameters for all SRVCTL Commands
Single-character parameters have been deprecated in Oracle Database 12c.
Use the full keyword for each parameter instead. To support older tools and scripts that still use single-character parameters, the current version of SRVCTL supports both single-character parameters and full keyword parameters.
The command reference in this appendix shows the keywords for each SRVCTL
command. Table A-2 lists the deprecated single-character parameters.
Table A-2 Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
A address {VIP_name |
IP}/netmask/
[if1[|if2...]]
VIP address specification for node applications
Node applications,
VIP, network, Listener,
SCAN VIP, and SCAN listener commands
Server Control Utility Reference A-7
Deprecated SRVCTL Subprograms or Commands
Table A-2 (Cont.) Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
a a a a a a
B c c c d d all diskgroup
diskgroup_list
All resources of that kind
Comma-delimited list of Oracle ASM disk groups srvctl config database
Common
Database, instance,
Oracle ASM, disk group, and file system commands
Common detail
Print detailed configuration information available
available_list
A comma-delimited list of available instances abort viponly
Abort failed online relocation
Display VIP configuration rlbgoal currentno de cardinali ty dbtype db
or database device
Service and server pool commands
Relocate database
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
{NONE|
SERVICE_TIME|
THROUGHPUT}
current_node
{UNIFORM|
SINGLETON}
The runtime load balancing goal of a service
Node name from which to relocate the service
Whether the service should run on every active server in the server pool
(UNIFORM) or just one server
(SINGLETON)
Service and server pool commands
Service and server pool commands
Service and server pool commands
type
Type of database:
Oracle RAC One
Node, Oracle RAC, or single instance
db_unique_name
Database unique name
Database, instance,
Oracle ASM, disk group, and file system commands
Common
volume_device
Volume device path Database, instance,
Oracle ASM, disk group, and file system commands
A-8 Oracle Real Application Clusters Administration and Deployment Guide
Deprecated SRVCTL Subprograms or Commands
Table A-2 (Cont.) Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
d e e e f g g g h i i
I i domain emport
Display subdomain served by GNS
em_port_number
Local listen port for
Oracle Enterprise
Manager
OC4J, home, CVU, and
GNS commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Service and server pool commands failovert ype server force importanc e
Candidate server list for Oracle RAC One
Node database
Force remove
Database, instance,
Oracle ASM, disk group, and file system commands
Common diskgroup gsdonly serverpoo l help
diskgroup_name
Disk group name
Display GSD configuration
server_pool_na me server_pool_li st
A server pool name
Comma-delimited list of database server pool names
File system, Diskgroup commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Service and server pool commands
Database, instance,
Oracle ASM, disk group, and file system commands
Common
Service and server pool commands instance ip oldinst
{NONE|SESSION
BASIC|
TRANSACTION}
server_list
The failover type for a service
number instance_name instance_list
A number that represents the importance of the server pool
Instance name prefix for administratormanaged Oracle
RAC One Node database
A comma-delimited list of instance names
ip_address
VIP address on which GNS is to listen
instance_name
The old instance name
Database, instance,
Oracle ASM, disk group, and file system commands
OC4J, home, CVU, and
GNS commands
Service and server pool commands
Server Control Utility Reference A-9
Deprecated SRVCTL Subprograms or Commands
Table A-2 (Cont.) Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
i i j j k l l l l l scannumbe r vip acfspath clbgoal netnum list listener loglevel min onslocalp ort
scan_ordinal
_number
vip_name or
"vip_name_list
"
Ordinal number of the IP address for the
SCAN
VIP names
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Node applications,
GNS, VIP, network, listener, SCAN VIP, and SCAN listener commands
Database, instance,
Oracle ASM, disk group, and file system commands
acfs_path_list
Comma-delimited list of Oracle ACFS paths where the dependency on the database will be set
{SHORT|LONG}
The connection load balancing goal for a service
Service and server pool commands
network_number
The network number Service and server pool commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
OC4J, home, CVU, and
GNS commands
List all records in
GNS
OC4J, home, CVU, and
GNS commands
listener_name
The name of a listener
log_level
Specify the level (0-6) of logging that GNS should run with
ASM commands
OC4J, home, CVU, and
GNS commands
number port_number
The minimum size of the server pool
Oracle Notification
Service listening port for local client connections
Service and server pool commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
A-10 Oracle Real Application Clusters Administration and Deployment Guide
Deprecated SRVCTL Subprograms or Commands
Table A-2 (Cont.) Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
l m m m m n n n n n n role domain failoverm ethod multicast post path name node nodes dbname scanname servers
service_role
domain_name
{NONE|BASIC}
Comma-delimited list of server roles within double quotation marks
(
""
), where each role is one of
PRIMARY
,
PHYSICAL_STANDBY
,
LOGICAL_STANDBY
, or
SNAPSHOT_STANDBY
Service and server pool commands
The domain for the database
The failover method of a service
Database, instance,
Oracle ASM, disk group, and file system commands
Service and server pool commands
The port on which the GNS daemon is listening for multicast requests
mountpoint_pat h
Mountpoint path
OC4J, home, CVU, and
GNS commands
Database, instance,
Oracle ASM, disk group, and file system commands
OC4J, home, CVU, and
GNS commands
node_name node_list
Advertise a name through GNS using the given address
The name of a specific node
A comma-delimited list of node names
Common
File system commands
database_name
The database name
(DB_NAME), if different from the unique name specified by the
-db parameter scan_name
Fully-qualified
SCAN name
(includes the domain)
server_list
A comma-delimited list of candidate server names
Database, instance,
Oracle ASM, disk group, and file system commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Service and server pool commands
Server Control Utility Reference A-11
Deprecated SRVCTL Subprograms or Commands
Table A-2 (Cont.) Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
n o p p p
P p q q r r r targetnod e
node_name
Node name to which to relocate the service
Service and server pool commands oraclehom e
oracle_home $ORACLE_HOME
path Database commands endpoints [TCP:]port
_number[/IPC:
key][/NMP:pipe
_name][/TCPS:
s_port][/SDP:
port] port
SCAN listener endpoints
The port which the
GNS daemon uses to communicate with the DNS server
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
OC4J, home, CVU, and
GNS commands rmiport tafpolicy spfile
port_number
{NONE|BASIC}
OC4J RMI port number
TAF policy specification
spfile_locatio n
Server parameter file path
OC4J, home, CVU, and
GNS commands
Service and server pool commands
Database, instance,
Oracle ASM, disk group, and file system commands
Service commands notificat ion query
{TRUE|FALSE}
Whether FAN is enabled for OCI connections
Query GNS for the records belonging to a name preferred
preferred_list
A comma-delimited list of preferred instances onsremote port relocate
port_number
Oracle Notification
Service listening port for connections from remote hosts
Relocate the VIP
OC4J, home, CVU, and
GNS commands
Service and server pool commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
A-12 Oracle Real Application Clusters Administration and Deployment Guide
Deprecated SRVCTL Subprograms or Commands
Table A-2 (Cont.) Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
r r s s s s
S s s t t revert role onsonly skip statfile status subnet service startopti on checkinte rval edition
role_type
Remove target node of failed online relocation request from the candidate server list of administratormanaged Oracle
RAC One Node database
Relocate database
Role of the standby database:
PRIMARY
,
PHYSICAL_STANDBY
,
LOGICAL_STANDBY
, or
SNAPSHOT_STANDBY
Database, instance,
Oracle ASM, disk group, and file system commands
Display Oracle
Notification Service daemon configuration
Skip checking the ports
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Listener, SCAN, and
SCAN listener.
file_name
subnet/net
_mask/[if1[|
if2...]]
edition_name
The file path of the
state_file
created by a previously executed srvctl stop home command
Display the status of
GNS
Network address specification for a network
service_name
service_name_l ist
The name of a service
A comma-delimited list of service names
start_options
Startup options for the database (mount, open, read only)
time_interval
Interval in minutes between checks
The initial session edition of a service
OC4J, home, CVU, and
GNS commands
OC4J, home, CVU, and
GNS commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Service and server pool commands
Database, instance,
Oracle ASM, disk group, and file system commands
OC4J, home, CVU, and
GNS commands
Service and server pool commands
Server Control Utility Reference A-13
Deprecated SRVCTL Subprograms or Commands
Table A-2 (Cont.) Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
t t
T t t t t u u u u u v envs "name_list"
A list of environment variables
Common namevals nameval update remoteser vers
"name=
value,..."
"name=value"
Names and values of environment variables
Name and value of a single environment variable
instance_name
The new instance name
host_name[:
port_number]
[,host_name[:
port_number]..
.]
List of remote host name and port number pairs for
Oracle Notification
Service daemons outside this cluster stopoptio n
stop_options
Stop options for the database (
NORMAL
,
TRANSACTIONAL
,
IMMEDITATE
, or
ABORT
) toversion
target_version
Version to which you are downgrading
Common
Common
Service and server pool commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Database, instance,
Oracle ASM, disk group, and file system commands max nettype newinst
number network_type
Maximum size of the server pool
The network server type, which can be
STATIC
,
DHCP
, or
MIXED
Database, instance,
Oracle ASM, disk group, and file system commands
Service and server pool commands
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Service commands update user verbose
oracle_user
Add a new instance to the service configuration
Update SCAN listeners to match the number of SCAN
VIPs
Oracle user or other authorized user to mount and unmount file systems
Verbose output
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Database, instance,
Oracle ASM, disk group, and file system commands
Common
A-14 Oracle Real Application Clusters Administration and Deployment Guide
Deprecated SRVCTL Subprograms or Commands
Table A-2 (Cont.) Deprecated Single-Character Parameters for SRVCTL Commands
Long Form Values Description Related Commands Single
Letter
v
V w w w x x y y z z volume versions failoverd elay nettype timeout dtp node noprompt policy failoverr etry rmdepondi sk
volume_name number
{AUTOMATIC |
MANUAL}
Name of a volume
Failover delay
Database, instance,
Oracle ASM, disk group, and file system commands
Common
Service and server pool commands
network_type timeout
The network server type, which can be
STATIC
MIXED
,
DHCP
, or
Online relocation timeout in minutes
Node applications,
VIP, network, listener,
SCAN VIP, and SCAN listener commands
Database, instance,
Oracle ASM, disk group, and file system commands
Service and server pool commands
{TRUE | FALSE}
Whether to enable distributed transaction processing
node_name
Node name (use this parameter only with noncluster databases)
Common
Suppress the confirmation prompt
Management policy for the resource
Common
number
Number of failover retries
To remove a database's dependency upon disk groups
Database, instance,
Oracle ASM, disk group, file system, service and server pool commands
Service and server pool commands
Database, instance,
Oracle ASM, disk group, and file system commands
Miscellaneous SRVCTL Commands and Parameters
The following command parameters have been deprecated in this release:
Server Control Utility Reference A-15
SRVCTL Command Reference
Table A-3 Deprecated Commands and Parameters for SRVCTL
Command
srvctl modify asm srvctl modify instance
Deprecated Parameters
-node
node_name
-z
Instead, use the
-node
option with the value set to
"" srvctl modify gns srvctl modify service
[-ip ip_address] [-advertise host_name -address
address] [-delete host_name -address address] [createalias name -alias alias] [-deletealias
alias]
Use the srvctl update gns
command instead.
srvctl * oc4j
The oc4j
noun has been deprecated and replaced with qosmserver
. SRVCTL still accepts the oc4j
noun until it is desupported.
srvctl add service
The
PRECONNECT option with the
-tafpolicy
parameter is deprecated.
The
-failovermethod {NONE | BASIC}
is deprecated.
The
PRECONNECT option with the
-tafpolicy
parameter is deprecated.
SRVCTL Command Reference
A comprehensive list of SRVCTL commands to use in Oracle RAC environments.
SRVCTL commands, object names, and parameters are case sensitive. Database, instance, listener, and service names are case insensitive and case preserving. You cannot create listener names that differ only in case, such as LISTENER and listener.
SRVCTL uses the following command syntax: srvctl command object [parameters]
In SRVCTL syntax:
•
command
is a verb such as start
, stop
, or remove
•
object
(also known as a noun) is the target or object on which SRVCTL performs the command, such as database or instance. You can also use object abbreviations.
•
parameters
extend the use of a preceding command combination to include additional parameters for the command. For example, the
-instances parameter indicates that a comma-delimited list of preferred instance names follows; the
-instance
parameter only permits one value and not a list of names. Do not use spaces between the items in a comma-delimited list.
Note:
If specifying a comma-delimited list in Windows, then you must enclose the list within double quotation marks (
""
).
lists the keywords that can be used for the
object
portion of SRVCTL commands. You can use either the full name or the abbreviation for each object
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SRVCTL Command Reference keyword. The Purpose column describes the object and the actions that can be performed on that object.
Table A-4 Object Keywords and Abbreviations
Object
Database
Instance
Keyword
database instance inst
Purpose
To add, modify, manage environment variables for, list the configuration of, enable, disable, start, stop, and obtain the status of databases, and also to upgrade, downgrade, and remove database configuration information about databases.
To add, modify, enable, disable, start, stop, obtain the status of, and remove database instances.
Listener
Network
Node applications
Oracle Notification
Service
Single client access name (SCAN)
SCAN listener
Service
Virtual IP listener lsnr
To add, modify, manage environment variables for, list the configuration of, enable, disable, start, stop, obtain the status of, and remove listeners network nodeapps
To add, modify, list the configuration of, and remove a non-default Network
Note:
The node applications object, and the config
and modify
commands also manage the default network.
To add, modify, manage environment variables for, list the configuration of, enable, disable, start, stop, obtain the status of, and remove node applications ons scan
To add, configure, enable, start, obtain the status of, stop, disable, and remove Oracle Notification
Service instances only for Oracle Restart
To add, list the configuration of, modify, enable, disable, start, stop, relocate, obtain the status of, and remove SCAN VIPs scan_listener
To add, list the configuration of, modify, enable, disable, start, stop, relocate, obtain the status of, and remove SCAN listeners service vip
To add, modify, list the configuration of, enable, disable, start, stop, obtain the status of, relocate, and remove services
To add, manage environment variables for, list the configuration of, enable, disable, start, stop, obtain the status of, and remove a VIP
srvctl add database
Adds a database configuration to Oracle Clusterware.
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SRVCTL Command Reference
Syntax
srvctl add database -db db_unique_name [-eval]
-oraclehome oracle_home [-node node_name] [-domain domain_name]
[-spfile spfile] [-pwfile password_file_path]
[-dbtype {RACONENODE | RAC | SINGLE} [-server "server_list"]]
[-instance instance_name] [-timeout timeout]]
[-role {PRIMARY | PHYSICAL_STANDBY | LOGICAL_STANDBY | SNAPSHOT_STANDBY"]
[-startoption start_options] [-stopoption stop_options] [-dbname db_name]
[-acfspath "acfs_path_list"] [-policy {AUTOMATIC | MANUAL | NORESTART}]
[-serverpool "server_pool_list" [-pqpool "pq_pool_list"]]
[-diskgroup "disk_group_list"] [-css_critical {yes | no}] [-cpucount
cpu_count]
[-memorytarget memory_target] [-maxmemory max_memory] [-cpucap cpu_cap] [defaultnetnum network_number] [-verbose]
Parameters
Table A-5 srvctl add database Command Parameters
Parameter Description
-db db_unique_name
Specify the unique name of the database.
-eval
-oraclehome
oracle_home
Use this parameter to hypothetically evaluate the impact of the command on the system.
Note:
You can only use this parameter with a policy-managed database.
Specify the path for the Oracle database home directory.
-node node_name
-domain db_domain
Specify the node name on which you want to register a noncluster, or single instance, Oracle database.
Note:
This parameter can be used only with Oracle Clusterware and can be used with the
-serverpool
parameter to create a policy-managed, noncluster database.
Specify the domain for the database.
Note:
You must use this parameter if you set the
DB_DOMAIN initialization parameter for the database.
-spfile spfile
-pwfile
password_file_path
-dbtype
{RACONENODE | RAC
| SINGLE}
-server
server_list
Specify the path name of the database server parameter file.
Enter the full path to the location of the password file.
Specify the type of database you are adding: Oracle RAC One
Node, Oracle RAC, or single instance. The default is
RAC
unless you specify the
-node node_name
parameter, and the
-type parameter defaults to
SINGLE
.
List candidate servers for Oracle RAC One Node databases.
Note:
You can use this parameter only with administratormanaged Oracle RAC One Node databases. If your Oracle RAC
One Node database is policy managed, then you cannot use this parameter.
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Table A-5 (Cont.) srvctl add database Command Parameters
Parameter
-instance
instance_name
-timeout timeout
-role {PRIMARY |
PHYSICAL_STANDBY |
LOGICAL_STANDBY |
SNAPSHOT_STANDBY}
-startoption
start_options
Description
Specify the instance name prefix for Oracle RAC One Node databases. The default value for this parameter is the first 12 characters of the global unique name of the database.
Note:
You can use this parameter only with administratormanaged Oracle RAC One Node databases. If your Oracle RAC
One Node database is policy managed, then you cannot use this parameter.
Specify the online database relocation timeout, in minutes, for
Oracle RAC One Node databases. The default is
30
.
Specify the role of the database in an Oracle Data Guard configuration. The default is
PRIMARY
.
-stoption
stop_options
Startup options for the database, such as
OPEN
,
MOUNT
, and
NOMOUNT
. The default value is
OPEN
.
Notes:
• For multi-word startup options, such as read only
and read write
, separate the words with a space and enclose in double quotation marks (
""
). For example,
"read only"
.
• When performing a switchover in an Oracle Data Guard configuration, the
-startoption
for a standby database that becomes a primary database is always set to
OPEN
after the switchover.
Specify stop options for the database, such as
NORMAL
,
TRANSACTIONAL
,
IMMEDIATE
, and
ABORT
.
-dbname db_name
-acfspath
"acfs_path_list"
Specify the name of the database, if it is different from the unique name given by the
-db
parameter.
A single Oracle ACFS path or a comma-delimited list of Oracle
ACFS paths enclosed in double quotation marks (
""
) where the database's dependency is set.
Use this parameter to create dependencies on Oracle ACFS file systems other than
ORACLE_HOME
, such as for when the database uses
ORACLE_BASE
on a file system that is different from the
ORACLE_HOME
file system.
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Table A-5 (Cont.) srvctl add database Command Parameters
Parameter
-policy {AUTOMATIC
| MANUAL |
NORESTART}
Description
Specify the management policy for the database.
•
AUTOMATIC
(default): The database is automatically restored to its previous running condition (started or stopped) upon restart of the database host computer.
•
MANUAL
: The database is never automatically restarted upon restart of the database host computer. A
MANUAL
setting does not prevent Oracle Clusterware from monitoring the database while it is running and restarting it if a failure occurs.
•
NORESTART
: Similar to the
MANUAL
setting, the database is never automatically restarted upon restart of the database host computer. A
NORESTART
setting, however, never restarts the database even if a failure occurs.
-serverpool
"server_pool_name"
[-pqpool
"pq_pool_name"]
-diskgroup
"disk_group_list"
Specify the name of a server pool used to control database placement. If you do not specify this parameter, then it defaults to the Generic server pool.
You can optionally also specify the name of a parallel query server pool to be used by the database.
Notes:
• This parameter can only be used with Oracle Clusterware.
You can use this parameter with the
-node
parameter but the server pool must have
MAX_SIZE=1
and exactly one configured server (the one you specify in
-node
).
• After you add server pools, you can assign services to them using the
command.
Specify a comma-delimited list of Oracle ASM disk groups if database uses Oracle ASM storage.
-css_critical {YES
| NO}
-cpucount
cpu_count
You can add weight to a service by setting this parameter to
YES
.
In the event of a node failure within the cluster, Oracle
Clusterware will evict the node with the least amount of weight, ensuring that critical services remain available.
Note:
You can use this parameter only on an administratormanaged node. Should the node become policy managed, at some point, this parameter will no longer apply.
Specify the number of CPUs. The default value is 0.
-memorytarget
memory_target
-maxmemory
max_memory
Specify the target memory, in MB, to be allocated for the database.
The default is 0.
Specify the maximum memory, in MB, to be allocated for the resource. If you specify
-memorytarget
but not
-maxmemory
, then
-maxmemory
will be the default value of 0. Both
maxmemory
and
-memorytarget
are validated as long as
memorytarget
is less than or equal to
-maxmemory
.
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Table A-5 (Cont.) srvctl add database Command Parameters
Parameter
-cpucap cpu_cap
-defaultnetnum
network_number
Description
Specify a percentage from 1 to 100 that is the maximum utilization of the workload CPUs the database requires. The default is 0.
Specify a network number (an integer) to which services will default in the event you do not specify a network number when you add the service. The number must match the value of the
netnum
parameter you specified when you added the network.
Examples
An example of this command to add a policy-managed Oracle RAC database is:
$ srvctl add database -db crm -oraclehome /u01/oracle/product/12c/mydb
-domain example.com -spfile +diskgroup1/crm/spfilecrm.ora
-role PHYSICAL_STANDBY -startoption MOUNT -dbtype RAC -dbname crm_psd
-policy MANUAL -serverpool "svrpool1,svrpool2" -diskgroup "dgrp1,dgrp2"
An example of this command to add an administrator-managed database is:
$ srvctl add database -db crm -oraclehome /u01/oracle/product/12c/mydb
-domain example.com
srvctl config database
Displays the configuration for an Oracle RAC database or lists all configured databases that are registered with Oracle Clusterware.
Syntax
srvctl config database [-db db_unique_name] [-all] [-verbose]
Parameters
Table A-6 srvctl config database Command Parameters
Parameter
-db db_unique_name
Description
Unique name for the database. If you do not specify this parameter, then the utility displays the configuration of all database resources.
Print detailed configuration information.
-all
Display verbose output.
-verbose
Example
This command returns output similar to the following:
$ srvctl config database -d main4
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Database unique name: main
Database name:
Oracle home: /ade/mjkeenan_main4/oracle
Oracle user: mjkeenan
Spfile:
Password file:
Domain:
Start options: open
Stop options: immediate
Database role: PRIMARY
Management policy: AUTOMATIC
Server pools:
Disk Groups:
Mount point paths:
Services: test
Type: RAC
Start concurrency:
Stop concurrency:
OSDBA group: dba
OSOPER group: oper
Database instances: main41,main42
Configured nodes: mjkeenan_main4_0,mjkeenan_main4_1
CSS critical: no
CPU count: 0
Memory target : 0
Maximum memory: 0
CPU cap: 0
Database is administrator managed
srvctl convert database
Converts a database either to or from an Oracle RAC One Node database.
Syntax
Use this command with one of the following syntax models: srvctl convert database -db db_unique_name -dbtype RACONENODE
[-instance instance_name] [-timeout timeout] srvctl convert database -db db_unique_name -dbtype RAC [-node node_name]
Parameters
Table A-7 srvctl convert database Command Parameters
Parameter Description
-db db_unique_name
Specify the unique name for the database.
Note:
If you specify a noncluster database, then command returns an error instructing you to use rconfig
to convert the noncluster database to Oracle RAC or Oracle RAC One Node.
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Table A-7 (Cont.) srvctl convert database Command Parameters
Parameter
-dbtype RACONENODE
| RAC
Description
Specify the type of database to which you are converting, either
Oracle RAC One Node or Oracle RAC.
Note:
If there is an ongoing or failed online database relocation, then the command returns an error instructing you to first complete or abort the online database relocation and then rerun the command.
-instance
instance_name
-timeout timeout
Optionally, you can specify an instance name prefix for Oracle
RAC One Node databases. The default value for this parameter is the first 12 characters of the global unique name of the database.
Notes:
• You can use this parameter only when converting from an
Oracle RAC database to an Oracle RAC One Node database.
• In order for the converted instance to come online, you must restart the database using the srvctl stop/start database
commands.
Optionally, you can specify online database relocation timeout, in minutes, for Oracle RAC One Node databases. The default is
30
.
-node node_name
Optionally, you can specify the name of the node for an administrator-managed Oracle RAC database. The default is the first candidate.
Note:
If you do not specify a node name or you specify a node name where the database is not running, then the command returns an error instructing you specify the correct node.
Example
An example of this command is:
$ srvctl convert database -db myDB -dbtype RACONENODE -instance myDB3
srvctl disable database
Disables a database. If the database is a cluster database, then its instances are also disabled.
Syntax and Parameters
Use the srvctl disable database
command with the following syntax: srvctl disable database -db
db_unique_name
[-node
node_name
]
Table A-8 srvctl disable database Parameters
Parameter Description
Database name
-db database_name
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Table A-8 (Cont.) srvctl disable database Parameters
Parameter
-node node_name
Description
Disables the database from running on the named node.
Note:
This parameter can be used only with Oracle
Clusterware.
Example
An example of this command is:
$ srvctl disable database -db mydb1
srvctl disable diskgroup
Disables a specific disk group on a number of specified nodes.
Syntax and Parameters
Use the srvctl disable diskgroup
command with the following syntax: srvctl disable diskgroup -diskgroup
diskgroup_name
[-node "
node_list
"]
Table A-9 srvctl disable diskgroup Parameters
Parameter Description
The Oracle ASM disk group name.
-diskgroup diskgroup_name
-node "node_list"
Comma-delimited list of node names on which to disable the disk group
This parameter is only available with Oracle
Clusterware.
Example
An example of this command is:
$ srvctl disable diskgroup -diskgroup dgroup1 -node "mynode1,mynode2"
srvctl add instance
Adds a configuration for an instance to your cluster database configuration.
You can only use this command for administrator-managed databases. If you have a
policy-managed database, then use the srvctl modify srvpool
command to add an instance to increase either the maximum size, minimum size, or both, of the server pool used by the database.
Syntax
srvctl add instance -db db_unique_name -instance instance_name
-node node_name [-force]
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Parameters
Table A-10 srvctl add instance Command Parameters
Parameter Description
-db db_unique_name
The unique name of the database you are adding the instance to
The name of the instance you are adding
-instance
instance_name
-node node_name
-force
The name of the node on which you are creating the instance
Optionally, you can force the add operation, even though some resources will be stopped.
Usage Notes
• This command increments the
CARDINALITY
resource attribute.
• This command is only available with Oracle Clusterware and Oracle RAC.
• If you attempt to use this command on an Oracle RAC One Node database, then the command returns an error stating you must convert the database to Oracle
RAC.
Examples
Examples of this command are:
$ srvctl add instance -db crm -instance crm01 -node gm01
$ srvctl add instance -db crm -instance crm02 -node gm02
$ srvctl add instance -db crm -instance crm03 -node gm03
srvctl disable instance
Disables an instance. If the instance that you disable with this command is the last enabled instance, then this operation also disables the database.
Note:
• This command is only available with Oracle Clusterware and Oracle
RAC.
• If you run this command on an Oracle RAC One Node database, then the command returns an error instructing you to use the database
noun, instead.
Syntax and Parameters
Use the srvctl disable instance
command with the following syntax: srvctl disable instance -db
db_unique_name
-instance
instance_name_list
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Table A-11 srvctl disable instance Parameters
Parameter Description
Unique name for the database
-db db_unique_name
Comma-delimited list of instance names
-instance instance_name_list
Example
An example of this command is:
$ srvctl disable instance -db crm -instance "crm1,crm3"
srvctl add listener
Adds a listener to every node in a cluster.
Syntax
Use this command with one of the following syntax models.
To create an Oracle Database listener: srvctl add listener [-listener listener_name] [-netnum network_number] [-oraclehome
Oracle_home]
-user user_name [-endpoints "[TCP:]port_list[:FIREWALL={ON|OFF}][/IPC:key][/
NMP:pipe_name]
[/{TCPS|SDP|EXADIRECT}port_list[:FIREWALL={ON|OFF}]]" [-group group_name]] [invitednodes "node_list"]
[-invitedsubnets "subnet_list"] [-skip]
To create an Oracle ASM listener: srvctl add listener [-listener listener_name] -asmlistener [-subnet subnet]
[-endpoints "[TCP:]port_list[:FIREWALL={ON|OFF}][/IPC:key][/NMP:pipe_name]
[/{TCPS|SDP|EXADIRECT}port_list[:FIREWALL={ON|OFF}]]" [-group group_name]] [invitednodes "node_list"]
[-invitedsubnets "subnet_list"] [-skip]
To create a Leaf listener: srvctl add listener [-listener listener_name] -leaflistener [-subnet subnet]
[-endpoints "[TCP:]port_list[:FIREWALL={ON|OFF}][/IPC:key][/NMP:pipe_name]
[/{TCPS|SDP|EXADIRECT}port_list[:FIREWALL={ON|OFF}]]" [-group group_name]] [invitednodes "node_list"]
[-invitedsubnets "subnet_list"] [-skip]
To create a SCAN listener, use the srvctl add scan_listener
command.
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Parameters
Table A-12 srvctl add listener Command Parameters
Parameter
-listener
listener_name
-netnum
network_number
-oraclehome
oracle_home
-user user_name
Description
Specify a listener name. This parameter is optional.
If you do not specify this parameter, then the name of the listener defaults to
LISTENER
for a database listener,
LISTENER_ASM
for an Oracle ASM listener, and
LISTENER_LEAF
for a Leaf Node listener.
The optional network number from which VIPs are obtained. If not specified, the VIPs are obtained from the same default network from which the nodeapps
VIP is obtained.
Note:
Use this parameter when you add an Oracle Database listener.
Specify an Oracle home for the cluster database. If you do not include this parameter, then SRVCTL uses the Grid home by default.
Note:
Use this parameter when you add an Oracle Database listener.
Use this parameter to set the user that will run the listener to a less privileged user. Oracle recommends using this parameter to increase security.
Notes:
• You must be logged in as root
to run this command and specify the
-user
parameter.
• Use this parameter when you add an Oracle Database listener.
• When you use the
-user
parameter, ensure the following:
The listener log directory in
ORACLE_BASE
and the
Grid_home/network/admin/user_name
directory must both exist on each node before you can use this parameter. Additionally,
user_name
must have read, write, and execute permission in the directory.
The
$ORACLE_HOME/network/admin/ endpoints_listener.ora
file exists and
user_name
has read and write permission on it.
The
$ORACLE_BASE/diag/tnslsnr/host_name/
lower_case_listener_name
directory exists and
user_name
has read, write, and execute permission on it.
• Before you can use LSNRCTL to manage a listener, you must set
TNS_ADMIN
to
Grid_home/network/admin/
user_name
.
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Table A-12 (Cont.) srvctl add listener Command Parameters
Parameter
-endpoints
"[TCP:]port_list[:
FIREWALL={ON|OFF}]
[/IPC:key] [/
NMP:pipe_name][/
{TCPS|SDP|
EXADIRECT}port_lis
t[:FIREWALL={ON|
OFF}]]"]
Description
Protocol specifications for the listener. Use
port_list
to specify a comma-delimited list of TCP ports or listener endpoints.
If you do not specify the
-endpoints
parameter for an Oracle
Database listener, then SRVCTL searches for a free port between
1521 and 1540.
You can also specify endpoints for TCPS, SDP, and EXADIRECT ports.
Note:
You can modify this attribute using Online Resource
Attribute Modification.
-group group_name
Optionally, you can use the
-group
parameter with
-endpoints to specify a group for the secure endpoint.
-invitednodes
"node_list"
-invitedsubnets
"subnet_list"
-skip
-asmlistener
Specify a comma-delimited list of node names allowed to register with the listener.
Specify a comma-delimited list of subnets allowed to register with the listener.
Indicates you want to skip the checking of ports.
Specifies the listener type as an Oracle ASM listener. If you do not specify the
-listener
parameter, then the name of the Oracle
ASM listener defaults to
LISTENER_ASM
.
Note:
You can only use this parameter with Oracle Clusterware.
-leaflistener
-subnet subnet
Specifies the listener type is a Leaf Node listener. If you do not specify the
-listener
parameter, then the name of the Leaf
Node listener defaults to
LISTENER_LEAF
.
Note:
You can only use this parameter with Oracle Clusterware.
Specifies the subnet to use for an Oracle ASM or Leaf Node listener.
Note:
You can only use this parameter with Oracle Clusterware.
Usage Notes
You must run this command as root
user on Linux and UNIX platforms when you specify the
-user
parameter.
Example
The following command adds a listener named listener112
that is listening on ports 1341, 1342, and 1345 and runs from the Oracle home directory on every node in the cluster:
$ srvctl add listener -listener listener112 -endpoints "1341,1342,1345"
-oraclehome /u01/app/oracle/product/12.2.0/db1
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srvctl disable listener
Disables a listener resource.
Syntax and Parameters
Use the srvctl disable listener
command with the following syntax: srvctl disable listener [-listener
listener_name
] [-node
node_name
]
Table A-13 srvctl disable listener Parameters
Parameter
-listener listener_name
Description
Name of a listener resource. If you do not specify this parameter, the name of the listener defaults to
LISTENER
.
-node node_name
Name of a cluster node on which the listener you want to disable is running.
This parameter is only available with Oracle Clusterware.
Example
To disable the listener named listener_crm
on the node node5
, use this command:
$ srvctl disable listener -listener listener_crm -node node5
srvctl config listener
Displays configuration information of a specific listener that is registered with Oracle
Clusterware.
Syntax
srvctl config listener [-listener listener_name | -asmlistener | -leaflistener]
[-all]
Parameters
Table A-14 srvctl config listener Command Parameters
Parameter
-listener listener_name | asmlistener | -leaflistener
Description
The name of a specific listener name or the type of listener (Oracle ASM or Leaf Node).
If you do not specify this parameter, then SRVCTL displays the configuration for the default database listener.
-all
Print detailed configuration information.
Example
This command returns output similar to the following:
Name: LISTENER_LEAF
Subnet: 10.100.200.195
Type: type
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Owner: scott
Home: Grid_home
End points: TCP:1521
srvctl add network
Adds a static or dynamic network.
If your server connects to more than one network, then you can use this command to configure an additional network interface for Oracle RAC, allowing you to create VIPs on multiple public networks.
Syntax
srvctl add network [-netnum net_number] -subnet subnet/netmask[/if1[|if2|...]]
[-nettype {static | dhcp | autoconfig | mixed}]
[-leaf] [-pingtarget "ping_target_list"] [-verbose]
Parameters
Table A-15 srvctl add network Command Parameters
Parameter
-netnum net_number
-subnet subnet/netmask
[/if1[|if2|...]]
Description
Specify a network number. The default is 1.
Defines a subnet. If you do not specify any interface names, then the network uses any interface on the given subnet.
For IPv6,
netmask
is a prefix length, such as 64.
-nettype {static|dhcp| autoconfig|mixed}
-leaf
Specify the network type: static
, dhcp
, autoconfig
, or mixed
.
If you specify static
for the network type, then you must provide the virtual
IP address using the srvctl add vip command.
If you specify dhcp
for the network type, then the VIP agent obtains the IP address from a DHCP server.
If you specify autoconfig
for the network type, then the VIP agent generates a stateless IPv6 address for the network. You can only use autoconfig
for IPv6 networks. If the subnet/netmask specification is not for an IPv6 address, then
SRVCTL returns an error.
If you specify mixed
for the network type, then the VIP resource uses both a static IP address and an IP address obtained dynamically, either from a DHCP server for IPv4 or using stateless autoconfiguration for IPv6.
Specify the
-leaf
parameter when you want to create an application VIP network resource that runs only on Leaf Nodes and is used by application VIPs.
Specify a comma-delimited list of IP addresses or host names to ping.
[-pingtarget
"ping_target_list"]
-verbose
Verbose output.
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Usage Notes
• On Linux and UNIX systems, you must be logged in as root
and on Windows, you must be logged in as a user with Administrator privileges to run this command.
• This command is only available with Oracle Clusterware.
• Oracle only supports DHCP-assigned networks for the default network, not for subsequent networks.
• You can also use the
LISTENER_NETWORKS
database initialization parameter to control client redirects to the appropriate network.
Example
An example of this command is:
# srvctl add network -netnum 3 -subnet 192.168.3.0/255.255.255.0
srvctl config network
Displays the network configuration for the cluster.
Syntax
srvctl config network [-netnum network_number]
Usage Notes
• Specify the network for which you want to display configuration information.
• This command is only available with Oracle Clusterware.
Example
An example of this command is:
$ srvctl config network -netnum 2
srvctl add nodeapps
Adds a node application configuration to the specified node.
Syntax
Use this command with one the following syntax models, specifying either a specific node and VIP or a specific subnet and netmask: srvctl add nodeapps
{-node node_name -address {vip_name | ip_address}/netmask[/if1[|if2|..]] [-skip]}
[-emport em_port] [-onslocalport ons_local_port]
[-onsremoteport ons_remote_port] [-onshostport hostname_port_list]
[-remoteservers hostname_port_list [-verbose] srvctl add nodeapps -subnet subnet/netmask[/if1[|if2|...]] [-emport em_port]
[-onslocalport ons_local_port] [-onsremoteport ons_remote_port]
[-onshostport hostname_port_list] [-remoteservers hostname_port_list]
[-verbose]
Server Control Utility Reference A-31
SRVCTL Command Reference
Parameters
Table A-16 srvctl add nodeapps Command Parameters
Parameter
-node node_name
-address {vip_name |
ip_address}/netmask[/
if1[|if2|..]]}
-skip
-subnet subnet/netmask
[/if1[|if2 |...]]
-emport em_port
-onslocalport
ons_local_port
-onsremoteport
ons_remote_port
-onshostport
host_port_list
-remoteservers
host_port_list
-verbose
Description
The name of the node on which you want to create the node application. Node name is optional and unnecessary if you run the command on the local node.
This specification creates a traditional VIP node application on the specified node.
Note:
You must use this parameter for upgrade configurations and new, non-
DHCP configurations.
Specify this parameter to skip checking the reachability of the VIP address.
Creates a DHCP subnet. If you do not specify any interface names, then the VIPs use any interface on the given subnet.
Local port on which Oracle Enterprise Manager listens. The default port is 2016.
The Oracle Notification Service daemon listener port on its node.
If you do not specify this value, the Oracle Notification Service daemon listener port defaults to 6100.
Note:
The local port and remote port must each be unique.
The port number for remote Oracle Notification Service daemon connections.
If you do not specify a port number, the default value of 6200 is used for the
Oracle Notification Service remote port.
Note:
The local port and remote port must each be unique.
A list of
host[:port]
pairs of remote hosts that are part of the Oracle
Notification Service network but are not part of the Oracle Clusterware cluster
Note:
If
port
is not specified for a remote host, then
ons_remote_port
is used.
A list of
host[:port]
pairs for Oracle Notification Service daemons on servers that are not in the cluster.
Verbose output
Usage Notes
• On Linux and UNIX systems, you must be logged in as root
and on Windows, you must be logged in as a user with Administrator privileges to run this command.
• This command is only available with Oracle Clusterware.
Example
An example of this command is:
# srvctl add nodeapps -node crmnode1 -address 1.2.3.4/255.255.255.0
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srvctl config nodeapps
Displays the VIP configuration for each node in the cluster.
Note:
This command is only available with Oracle Clusterware.
Syntax
srvctl config nodeapps [-viponly] [-onsonly]
Usage Notes
Use
-viponly
to display the VIP address configuration. Use
-onsonly
to display the
Oracle Notification Service configuration.
Example
An example of this command is:
$ srvctl config nodeapps -viponly -onsonly
srvctl disable nodeapps
Disables node applications on all nodes in the cluster.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl disable nodeapps
command with the following syntax: srvctl disable nodeapps [-gsdonly] [-adminhelper] [-verbose]
Table A-17 srvctl disable nodeapps Parameters
Parameter Description
Disables GSD
-gsdonly
-adminhelper
Disable the Administrator helper only
Verbose output
-verbose
Example
An example of this command is:
$ srvctl disable nodeapps -gsdonly -verbose
Server Control Utility Reference A-33
SRVCTL Command Reference
srvctl add ons
Adds an Oracle Notification Service daemon to an Oracle Restart configuration.
Syntax
srvctl add ons [-l ons_local_port] [-r ons_remote_port]
[-t host[:port][,host[:port]][...]] [-v]
Parameters
Table A-18 srvctl add ons Command Parameters
Parameter
-l ons_local_port
-r ons_remote_port
-t host[:port]
[,host[:port]][...]
-v
Description
The Oracle Notification Service daemon listening port for local client connections
Note:
The local port and remote port must each be unique.
The Oracle Notification Service daemon listening port for connections from remote hosts
Note:
The local port and remote port must each be unique.
A list of comma-delimited
host:port
pairs of remote hosts that are part of the
Oracle Notification Service network but are not part of the Oracle Clusterware cluster
Note:
If
port
is not specified for a remote host, then
ons_remote_port
is used.
Verbose output
Usage Notes
This command is only available with Oracle Restart.
Example
An example of this command is:
$ srvctl add ons -l 6200
srvctl config ons
Displays configuration information for the Oracle Notification Service daemon.
Note:
This command is only available with Oracle Restart.
srvctl config ons
This command has no parameters.
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SRVCTL Command Reference
srvctl disable ons
Disables the Oracle Notification Service daemon for Oracle Restart installations.
srvctl disable ons [-verbose]
The only parameter for this command is
-v erbose, which indicates that verbose output should be displayed.
srvctl config qosmserver
Displays configuration information for the qosmserver
resource.
Note:
This command is only available with Oracle Clusterware.
Syntax
srvctl config qosmserver
Parameters
This command has no parameters.
Example
The following command displays the configuration information for the qosmserver resource.
$ srvctl config qosmserver
srvctl add scan
Adds Oracle Clusterware resources for the given SCAN.
Syntax
srvctl add scan -scanname scan_name [-netnum network_number]
Parameters
Table A-19 srvctl add scan Command Parameters
Parameter
-scanname scan_name
Description
A fully-qualified host name, which includes the domain name. If the network is dynamic, then you do not have to use fully-qualified host name but, if you choose to do so, then the domain must be the GNS subdomain.
Note:
You can modify this attribute using Online Resource Attribute
Modification.
-netnum network_number
The optional network number from which SCAN VIPs are obtained. If you do not specify this parameter, then the SCAN VIPs are obtained from the same default network from which the nodeapps
VIP is obtained.
Server Control Utility Reference A-35
SRVCTL Command Reference
Usage Notes
• This command creates the same number of SCAN VIP resources as the number of
IP addresses that SCAN resolves to, or 3 when
network_number
identifies a
and Oracle GNS configuration.
• For static networks, the addresses to which the SCAN resolves in DNS must match the address type of the subnet.
• For an IPv4 network, the SCAN must resolve to IPv4 addresses.
• This command is only available with Oracle Clusterware.
Example
An example of this command is:
# srvctl add scan -scanname scan.mycluster.example.com
srvctl config scan
Displays the configuration information for all SCAN VIPs, by default, or a specific
SCAN VIP identified by ordinal_number.
Syntax
srvctl config scan [[-netnum network_number] [-scannumber ordinal_number] | -all]
Parameters
Table A-20 srvctl config scan Command Parameters
Parameter
-netnum network_number
-scannumber
ordinal_number
-all
Description
Use this parameter to view the configuration of a specific
SCAN VIP.
Use this parameter to specify any one of the three SCAN
VIPs, using values from 1 to 3, for which you want to view the configuration.
Alternative to specifying network or ordinal numbers, you can use this parameter to view the configuration for all of the SCAN VIPs.
Usage Notes
This command is only available with Oracle Clusterware.
Example
This command returns output similar to the following:
$ srvctl config scan -scannumber 1
SCAN name: mjk12700890090-r, Network: 1
Subnet IPv4: 198.51.100.1/203.0.113.46/eth0, static
Subnet IPv6:
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SRVCTL Command Reference
SCAN 1 IPv4 VIP: 198.51.100.195
SCAN VIP is enabled.
SCAN VIP is individually enabled on nodes:
SCAN VIP is individually disabled on nodes:
srvctl disable scan
Disables all SCAN VIPs, by default, or a specific SCAN VIP identified by
ordinal_number
.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl disable scan
command with the following syntax: srvctl disable scan [-scannumber
ordinal_number
]
The only parameter available for this command is
-scannumber ordinal_number
, which represents which identifies any one of the three SCAN VIPs, and can take a range of values from 1 to 3.
Example
An example of this command is:
$ srvctl disable scan -scannumber 1
srvctl add scan_listener
Adds Oracle Clusterware resources for the SCAN listeners.
Syntax
srvctl add scan_listener [-listener lsnr_name_prefix] [-skip] [-netnum
network_number]
[-endpoints "[TCP:]port_list[:FIREWALL={ON|OFF}][/IPC:key][/NMP:pipe_name]
[/{TCPS|SDP|EXADIRECT}port_list[:FIREWALL={ON|OFF}]]" [-invitednodes node_list] [invitedsubnets subnet_list]
Parameters
Table A-21 srvctl add scan_listener Command Parameters
Parameter Description
The SCAN listener name prefix.
-listener
lsnr_name_prefix
-skip
Use this parameter to skip checking of the ports.
-netnum network_number
The optional network number from which SCAN VIPs are obtained. If you do not specify this parameter, then the SCAN VIPs are obtained from the same default network from which the nodeapps
VIP is obtained.
Server Control Utility Reference A-37
SRVCTL Command Reference
Table A-21 (Cont.) srvctl add scan_listener Command Parameters
Parameter
-endpoints
"[TCP:]port_list[:FIRE
WALL={ON|OFF}][/
IPC:key] [/
NMP:pipe_name][/{TCPS|
SDP|
EXADIRECT}port_list[:F
IREWALL={ON|OFF}]]"]
Description
Protocol specifications for the SCAN listener. Use
port_list
to specify a comma-delimited list of TCP ports or SCAN listener endpoints.
You can also specify endpoints for TCPS, SDP, and EXADIRECT ports.
Note:
You can modify this attribute using Online Resource Attribute
Modification.
-invitednodes
node_list
Use this parameter to specify a comma-delimited list of host names from outside the cluster that are allowed to register with the SCAN listener.
-invitedsubnets
subnet_list
Use this parameter to specify a comma-delimited list of subnets from outside the cluster that are allowed to register with the SCAN listener.
Usage Notes
• The number of SCAN listener resources created is the same as the number of
SCAN VIP resources.
• This command is only available with Oracle Clusterware.
Example
An example of this command is:
# srvctl add scan_listener -listener myscanlistener
srvctl config scan_listener
Displays the configuration information for all SCAN listeners, by default, or a specific listener identified by network number or ordinal_number.
Syntax
srvctl config scan_listener [[-netnum network_number] [-scannumber ordinal_number] |
-all]
Parameters
Table A-22 srvctl config scan_listener Command Parameters
Parameter
-netnum network_number
-scannumber
ordinal_number
Description
Use this parameter to view the configuration of the listener for a specific SCAN VIP.
Use this parameter to specify any one of the three SCAN
VIPs, using values from 1 to 3, for which you want to view the configuration of the listener.
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Table A-22 (Cont.) srvctl config scan_listener Command Parameters
Parameter
–all
Description
Alternative to specifying network or ordinal numbers, you can use this parameter to view the configuration of the listeners for all of the SCAN VIPs.
Usage Notes
This command is only available with Oracle Clusterware.
Example
This command returns output similar to the following:
$ srvctl config scan_listener -scannumber 1
SCAN Listener LISTENER_SCAN1 exists. Port: TCP:1529
Registration invited nodes:
Registration invited subnets:
SCAN Listener is enabled.
SCAN Listener is individually enabled on nodes:
SCAN Listener is individually disabled on nodes:
srvctl disable scan_listener
Disables all SCAN listeners, by default, or a specific listener identified by
ordinal_number
.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl disable scan_listener
command with the following syntax: srvctl disable scan_listener [-scannumber
ordinal_number
]
The only parameter available for this command is
-scannumber ordinal_number
, which identifies any one of the three SCAN listeners, and can take a range of values from 1 to 3.
Example
An example of this command is:
$ srvctl disable scan_listener -scannumber 1
srvctl add service
Adds services to a database and assigns them to instances.
Syntax
Use this command with one of the following syntax models.
Server Control Utility Reference A-39
SRVCTL Command Reference
To add a service to a policy-managed database: srvctl add service -db db_unique_name -service service_name [-eval]
-serverpool server_pool [-pdb pluggable_database]
[-cardinality {UNIFORM | SINGLETON}] [-edition edition_name]
[-netnum network_number] [-role "[PRIMARY][,PHYSICAL_STANDBY][,LOGICAL_STANDBY]
[,SNAPSHOT_STANDBY]"]
[-policy {AUTOMATIC | MANUAL}] [-notification {TRUE | FALSE}] [-rfpool pool_name]
[-clbgoal {SHORT | LONG}] [-failovertype {NONE|SESSION|SELECT|TRANSACTION}]
[-rlbgoal {NONE | SERVICE_TIME | THROUGHPUT}] [-dtp {TRUE | FALSE}]
[-failovermethod {NONE | BASIC}] [-failoverretry failover_retries]
[-drain_timeout timeout] [-stopoption {NONE|IMMEDIATE|TRANSACTIONAL}]
[-failoverrestore {NONE|LEVEL1}] [-failoverdelay failover_delay]
[-gsmflags gsm_flags] [-sql_translation_profile sql_translation_profile]
[-global {TRUE | FALSE}] [-maxlag max_lag_time] [-commit_outcome {TRUE|FALSE}]
[-retention retention_time] [-replay_init_time replay_initiation_time]
[-session_state {STATIC | DYNAMIC}] [-pqservice pq_service]
[-pqpool pq_pool] [-css_critical {yes | no}] [-force]
To add a service to an administrator-managed database: srvctl add service -database db_unique_name -service service_name
[-pdb pluggable_database] [-eval]
[-preferred preferred_list] [-available available_list]
[-netnum network_number] [-tafpolicy {BASIC | NONE}]
[-edition edition_name]
[-role "[PRIMARY][,PHYSICAL_STANDBY][,LOGICAL_STANDBY][,SNAPSHOT_STANDBY]"
[-policy {AUTOMATIC | MANUAL}] [-notification {TRUE | FALSE}]
[-clbgoal {SHORT | LONG}] [-failovertype {NONE|SESSION|SELECT|TRANSACTION}]
[-rlbgoal {NONE | SERVICE_TIME | THROUGHPUT}] [-dtp {TRUE | FALSE}]
[-failovermethod {NONE | BASIC}] [-failoverretry failover_retries]
[-drain_timeout timeout] [-stopoption {NONE|IMMEDIATE|TRANSACTIONAL}]
[-failoverrestore {NONE|LEVEL1}] [-failoverdelay failover_delay]
[-sql_translation_profile sql_translation_profile]
[-global {TRUE | FALSE}] [-maxlag max_lag_time] [-commit_outcome {TRUE|FALSE}]
[-retention retention_time] [-replay_init_time replay_initiation_time]
[-session_state {STATIC|DYNAMIC}] [-force] [-verbose]
To update the preferred and available lists of an existing service: srvctl add service -db db_unique_name -service service_name
-update {-prefered preferred_list | -available available_list} [-force]
[-verbose]
Parameters
The following table lists and describes all the srvctl add service
parameters and whether they can be used when adding a service to either an Oracle RAC database or noncluster database.
Table A-23 srvctl add service Command Parameters
Parameter Description
-db db_unique_name
Unique name for the database.
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Table A-23 (Cont.) srvctl add service Command Parameters
Parameter
-service
service_name
-eval
-edition
edition_name
sql_translation_pr ofile profile_name
-preferred
preferred_list
Description
The
service_name.service_domain
should be unique within the cluster unless you want to spread connections across multiple databases that offer the same service. If you do not specify the service domain as part of the service name (such as sales.example.com
), then the
DB_DOMAIN
database attribute is appended to the service name.
Note:
The
-service
parameter has a 4 kilobyte (KB) limit for its value. Therefore, the total length of the names of all services assigned to an instance cannot exceed 4 KB.
Use this parameter to hypothetically evaluate the impact of the command on the system.
Note:
You can only use this parameter with a policy-managed service.
The initial session edition of the service.
When an edition is specified for a service, all subsequent connections that specify the service use this edition as the initial session edition. However, if a session connection specifies a different edition, then the edition specified in the session connection is used for the initial session edition.
SRVCTL does not validate the specified edition name. During connection, the connect user must have
USE
privilege on the specified edition. If the edition does not exist or if the connect user does not have
USE
privilege on the specified edition, then an error is raised.
Use this parameter to specify a
for a service that you are adding after you have migrated applications from a non-Oracle database to an Oracle database.
This parameter corresponds to the SQL translation profile parameter in the
DBMS_SERVICE
service attribute.
Notes:
• Before using the SQL translation feature, you must migrate all server-side application objects and data to the Oracle database.
• Use the srvctl config service
command to display the
SQL translation profile.
A list of preferred instances on which the service runs when the database is administrator managed.
The list of preferred instances must be mutually exclusive with the list of available instances.
Note:
This parameter can be used only with Oracle RAC and only for administrator-managed databases.
Server Control Utility Reference A-41
SRVCTL Command Reference
Table A-23 (Cont.) srvctl add service Command Parameters
Parameter
-available
available_list
-serverpool
server_pool
-cardinality
{UNIFORM |
SINGLETON}
-netnum
network_number
-tafpolicy {BASIC
| NONE}
Description
A list of available instances to which the service fails over when the database is administrator managed.
The list of available instances must be mutually exclusive with the list of preferred instances.
Note:
This parameter can be used only with Oracle RAC and only for administrator-managed databases.
The name of a server pool used when the database is policy managed.
Note:
This parameter can be used only with Oracle RAC and only for policy-managed databases.
The cardinality of the service, either
UNIFORM
(offered on all instances in the server pool) or
SINGLETON
(runs on only one instance at a time).
Notes:
• This parameter can be used only with Oracle RAC and only for policy-managed databases.
• For policy-managed Oracle RAC One Node databases, all services must be
SINGLETON
.
Use this parameter to determine on which network this service is offered. The service is configured to depend on VIPs from the specified network.
Notes:
• If you omit this parameter, then the default is taken from the database configuration, which you specify using srvctl add database
or srvctly modify database
, with the
-defaultnetwork
parameter to specify the default network for that database's services.
• This parameter can be used only with Oracle RAC and Oracle
RAC One Node database configurations.
TAF policy specification (for administrator-managed databases only).
-role "[PRIMARY]
[,PHYSICAL_STANDBY
]
[,LOGICAL_STANDBY]
[,SNAPSHOT_STANDBY
]"
The service role. You can specify one or more roles in a commadelimited list.
Use this option to indicate that the service should only be automatically started upon database open when the Oracle Data
Guard database role matches one of the specified service roles.
Using SRVCTL to manually start a service is not affected by the service role.
Note:
The
-role
parameter is only used at database startup and by the Oracle Data Guard Broker. All manual service startup must specify the name of the service to be started by the user.
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Table A-23 (Cont.) srvctl add service Command Parameters
Parameter
-policy {AUTOMATIC
| MANUAL}
Description
Service management policy.
If
AUTOMATIC
(the default), then the service is automatically started upon restart of the database, either by a planned restart
(with SRVCTL) or after a failure. Automatic restart is also subject to the service role, however (the
-role
parameter).
If
MANUAL
, then the service is never automatically restarted upon planned restart of the database (with SRVCTL). A
MANUAL
setting does not prevent Oracle Clusterware from monitoring the service when it is running and restarting it if a failure occurs.
Note:
Using CRSCTL to stop and start the Oracle Clusterware restarts the service in the same way that a failure does.
-notification
{TRUE | FALSE}
Enable Fast Application Notification (FAN) for OCI connections.
-rfpool pool_name
-dtp {TRUE |
FALSE}
Specify the name of the reader farm server pool.
Indicates whether Distributed Transaction Processing should be enabled for this service. This service will either be a singleton service in a policy-managed database or a preferred service on a single node in an administrator-managed database.
Note:
This parameter can be used only with Oracle RAC.
-clbgoal {SHORT |
LONG}
-rlbgoal {NONE |
SERVICE_TIME |
THROUGHPUT}
-failovertype
{NONE | SESSION |
SELECT |
TRANSACTION}
-failovermethod
{NONE | BASIC}
-failoverretry
failover_retries
Connection Load Balancing Goal. Use a value of
SHORT
for this parameter for run-time load balancing, or if using an integrated connection pool. Use a value of
LONG
for this parameter for long running connections, such as batch jobs, that you want balanced by the number of sessions per node for the service.
Runtime Load Balancing Goal (for the Load Balancing Advisory).
Set this parameter to
SERVICE_TIME
to balance connections by response time. Set this parameter to
THROUGHPUT
to balance connections by throughput.
Failover type.
To enable Application Continuity for Java, set this parameter to
TRANSACTION
. To enable TAF for OCI, set this parameter to
SELECT
or
SESSION
.
Note:
If you set
-failovertype
to
TRANSACTION
, then you must set
-commit_outcome
to
TRUE
.
TAF failover method (for backward compatibility only).
If the failover type (
-failovertype
) is set to a value other than
NONE
, then you should choose
BASIC
for this parameter.
Note:
This parameter can be used only with Oracle RAC.
For Application Continuity and TAF, this parameter determines the number of attempts to connect after an incident.
Server Control Utility Reference A-43
SRVCTL Command Reference
Table A-23 (Cont.) srvctl add service Command Parameters
Parameter
-drain_timeout
timeout
-stopoption {NONE|
IMMEDIATE|
TRANSACTIONAL}
Description
Specify the time, in seconds, allowed for resource draining to be completed. Accepted values are an empty string (""), 0, or any positive integer. The default value is an empty string, which means that this parameter is not set. If it is set to 0, then draining occurs, immediately.
The draining period is intended for planned maintenance operations. During the draining period, all current client requests are processed, but new requests are not accepted. When set on the service this value is used when the command line value is not set.
Specify the mode in which the service is stopped. When set on the service, this value is used if you do not set the value on the command line.
IMMEDIATE
permits sessions to drain before the service is stopped.
TRANSACTIONAL
permits sessions to drain for the amount of time specified in the
-drain_timeout
parameter. The service is stopped when the time limit is reached and any remaining sessions are terminated.
If you specify
NONE
, then no sessions are terminated.
The default is taken from the service setting, when specified on the service. Otherwise the default is
NONE
.
Note:
You must use the
-stopoption
parameter with the
force
parameter.
-failoverrestore
{NONE|LEVEL1}
For Application Continuity, when you set the
failoverrestore
parameter, session states are restored before replaying. Use
LEVEL1
for ODP.NET and Java with Application
Continuity to restore the initial state.
For OCI applications using TAF or Application Continuity, setting
-failoverrestore
to
LEVEL1
restores the current state. If the current state differs from the initial state, then a TAF callback is required. This restriction applies only to OCI.
-failoverdelay
failover_delay
-gsmflags
gsm_flags
For Application Continuity and TAF, this parameter specifies the time delay (in seconds) between reconnect attempts per incident at failover.
Set locality and region failover values.
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Table A-23 (Cont.) srvctl add service Command Parameters
Parameter
-pdb
pluggable_database
Description
The name of the pluggable database (PDB).
Note:
You can specify a PDB property when you create or modify a service. The PDB property associates the service with the specified PDB. You can view the PDB property for a service by querying the ALL_SERVICES data dictionary view or, when using the SRVCTL utility, by running the srvctl config service command.
When you create or modify a service with the specified PDB,
SRVCTL does not check if the PDB exists. Before running this command, you must ensure that the PDB exists.
-global {TRUE |
FALSE}
-maxlag
maximum_lag_time
Indicates whether this is a Global Data Services service.
Note:
This parameter can only be used with Global Data Services.
Maximum replication lag time in seconds. Must be a non-negative integer. The default value is
ANY
.
-commit_outcome
{TRUE | FALSE}
-retention
retention_time
-replay_init_time
replay_initializat ion_time
Enable Transaction Guard; when set to
TRUE
, the commit outcome for a transaction is accessible after the transaction's session fails due to a recoverable outage.
If
-commit_outcome
is set to
TRUE
, then this parameter determines the amount of time (in seconds) that the commit outcome is retained in the database.
For Application Continuity, this parameter specifies the difference between the time, in seconds, of original execution of the first operation of a request and the time that the replay is ready to start after a successful reconnect. Application Continuity will not replay after the specified amount of time has passed. This parameter is intended to avoid the unintentional execution of a transaction when a system is recovered after a long period. The default is 5 minutes (
300
). The maximum value is 24 hours
(
86400
). If the
-failover_type
parameter is not set to
TRANSACTION
, then you cannot use this parameter.
-session_state
{STATIC | DYNAMIC}
For Application Continuity, this parameter specifies whether the session state that is not transactional is changed by the application. Oracle recommends a setting of
DYNAMIC
for most applications.
Note:
This parameter is considered only if
-failovertype
is set to
TRANSACTION
for Application Continuity. It describes how non-transactional is changed during a request. Examples of session state are NLS settings, optimizer preferences, event settings, PL/SQL global variables, temporary tables, advanced queues, LOBs, and result cache. If non-transactional values change after the request starts, then use the default,
DYNAMIC
. Most applications should use
DYNAMIC
mode. If you are unsure, then use
DYNAMIC
mode.
Server Control Utility Reference A-45
SRVCTL Command Reference
Table A-23 (Cont.) srvctl add service Command Parameters
Parameter
-pqservice
pq_service
-pqpool pq_pool
Description
Specify a parallel query service name.
-update {preferred
new_preferred_inst
ance | -available
new_available_inst
ance}
Specify a parallel query server pool.
Add a new preferred or available instance to the service configuration.
-preferred
specifies the name of the instance to add to the list of preferred instances for the service.
-available specifies the name of the instance to add to the list of available instances for the service.
-css_critical {yes
| no}
You can add weight to a service by setting this parameter to
YES
.
In the event of a node failure within the cluster, Oracle
Clusterware will evict the node with the least amount of weight, ensuring that critical services remain available.
Note:
You can use this parameter only on an administratormanaged node. Should the node become policy managed, at some point, this parameter will no longer apply.
-verbose
-force
Display verbose output.
Force the add operation even though a listener is not configured for a network.
Usage Notes
This command does not accept placement parameters for Oracle RAC One Node databases.
Examples
Use this example syntax to add the gl.example.com
service to the my_rac
database with Fast Application Notification enabled for OCI connections, a failover method of
BASIC
, a Connection Load Balancing Goal of
LONG
, a failover type of
SELECT
, and 180 failover retries with a failover delay of 5 seconds:
$ srvctl add service -db my_rac -service gl.example.com -notification TRUE failovermethod BASIC -failovertype SELECT -failoverretry 180 -failoverdelay 5 clbgoal LONG
Use this example syntax to add a named service to a database with preferred instances and available instances and enabled for TAF:
$ srvctl add service -db crm -service sales -preferred crm01,crm02 -available crm03 tafpolicy BASIC
srvctl config service
Displays the configuration for a service.
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Syntax
srvctl config service {-db db_unique_name [-service service_name]
| -serverpool pool_name [-db db_unique_name]} [-verbose]
Parameters
Table A-24 srvctl config service Command Parameters
Parameter
-db db_unique_name
-service service_name
-serverpool pool_name
-verbose
Description
Unique name for the database.
Optionally, you can specify the name of a service.
If you do not use this parameter, then SRVCTL displays the configuration information for all services configured for the database.
Alternatively, you can use this parameter to specify the name of a server pool for which you want to view the service configuration. Optionally, you can also specify a particular database on which the server pool resides.
Displays verbose output.
Usage Notes
The srvctl config service
command shows exactly the string value you specified for the edition using the srvctl add | modify service
commands. If you specified the edition in upper case, then srvctl config service
displays upper case. If it is surrounded by double quotation marks (
""
), then the command displays the double quotation marks. Otherwise, the command displays an empty string.
Examples
This command returns information similar to the following for a policy-managed database:
$ srvctl config service -db crm -service webapps
Service name: webapps
Service is enabled
Server pool: sales
Cardinality: SINGLETON
Disconnect: false
Service role: PRIMARY
Management policy: AUTOMATIC
DTP transaction: false
AQ HA notifications: false
Failover type: NONE
Failover method: NONE
TAF failover retries: 0
TAF failover delay: 0
Connection Load Balancing Goal: LONG
Runtime Load Balancing Goal: NONE
TAF policy specification: NONE
Service is enabled on nodes:
Service is disabled on nodes:
Edition: "my Edition"
Server Control Utility Reference A-47
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This command returns information similar to the following for a administratormanaged database:
$ srvctl config service -db crm -service webapps
Service name: webapps
Service is enabled
Server pool: sales
Cardinality: 1
Disconnect: false
Service role: PRIMARY
Management policy: AUTOMATIC
DTP transaction: false
AQ HA notifications: false
Failover type: NONE
Failover method: NONE
TAF failover retries: 0
TAF failover delay: 0
Connection Load Balancing Goal: LONG
Runtime Load Balancing Goal: NONE
TAF policy specification: NONE
Preferred instances: crm_1
Available instances:
Edition: "my Edition"
Service configuration for administrator-managed Oracle RAC One Node databases displays the one instance as preferred.
srvctl disable service
Disables a service. Disabling an entire service affects all of the instances, disabling each one. When the entire service is already disabled, a srvctl disable service operation on the entire service affects all of the instances and disables them; it just returns an error. This means that you cannot always use the entire set of service operations to manipulate the service indicators for each instance.
Syntax and Parameters
Use the srvctl disable service
command with the following syntax: srvctl disable service -db
db_unique_name
-servics
"service_name_list"
[-instance instance_name | -node
node_name
]
If you do not specify either the
-instance instance_name
or
-node node_name parameters, then the command disables the service on all nodes.
Table A-25 srvctl disable service Parameters
Parameter Description
Unique name for the database.
-database db_unique_name
-service "service_name_list"
Comma-delimited list of service names, or a single service name
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Table A-25 (Cont.) srvctl disable service Parameters
Parameter
-instance instance_name
-node node_name
Description
The name of the instance for which you want to disable the service.
Notes:
• Use this parameter with administrator-managed databases
• This parameter can be used only with Oracle
Clusterware and Oracle RAC
The name of the node on which to disable the service.
Notes:
• Use this parameter with policy-managed databases
• This parameter can be used only with Oracle
Clusterware and Oracle RAC
Examples
The following example globally disables two services for the
CRM
database:
$ srvctl disable service -db crm -service "crm,marketing"
The following example disables a service for the
CRM
database that is running on the
CRM1
instance, resulting in the service still being available for the database, but on one less instance:
$ srvctl disable service -db crm -service crm -instance crm1
srvctl add srvpool
Adds a server pool that is configured to host Oracle databases to a cluster.
Syntax
srvctl add srvpool -serverpool server_pool_name [-eval]
[-importance importance] [-min min_size] [-max max_size]
[-servers "node_list" | -category server_category] [-force] [-verbose]
Parameters
Table A-26 srvctl add srvpool Command Parameters
Parameter
-serverpool
server_pool_name
-eval
Description
The name of the server pool.
Use this parameter to hypothetically evaluate the impact of the command on the system.
-importance importance
The importance of the server pool (default value is
0
).
-min min_size
The minimum size of the server pool (default value is
0
).
Server Control Utility Reference A-49
SRVCTL Command Reference
Table A-26 (Cont.) srvctl add srvpool Command Parameters
Parameter
-max max_size
-servers "node_list"
-category
server_category
-force
-verbose
Description
The maximum size of the server pool. The default value is
-1
, which indicates that the size is unlimited.
A comma-delimited list of candidate node names enclosed in double quotation marks (
""
). The server pool will only include nodes on the candidate list, but not all nodes on the candidate list will necessarily be in the server pool.
Note:
In Oracle Database 12c, servers are assigned to server pools according to the value of the
-category
parameter.
The category of servers to use for the server pool, or
""
for the empty category value. You can use hub
for ora.hub.category
, leaf
for ora.leaf.category
, or you can define your own category. The default is ora.hub.category
.
Add the server pool, even if it requires stopping resources in other server pools.
Display verbose output.
Usage Notes
• SRVCTL prepends “ ora.
” to the name of the server pool.
• This command is only available with Oracle Clusterware.
Example
The following command adds a server pool named SP1, with importance set to 1, the minimum number of nodes in the server pool set to 3 and the maximum number of nodes in the server pool set to 7: srvctl add srvpool -serverpool SP1 -importance 1 -min 3 -max 7
srvctl config srvpool
Displays configuration information including name, minimum size, maximum size, importance, and a list of server names, if applicable, for a specific server pool in a cluster.
Syntax
srvctl config srvpool [-serverpool pool_name]
Parameters
The only parameter available for this command is
-serverpool pool_name
, which is the name of the server pool for which you want to display the configuration information.
Usage Notes
This command is only available with Oracle Clusterware.
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Example
An example of this command is:
$ srvctl config srvpool -serverpool dbpool
srvctl add vip
Adds a virtual IP address (VIP) to a node.
Syntax
srvctl add vip -node node_name -address {VIP_name|ip}/netmask[/if1[|if2|...]]
-netnum network_number [-skip] [-verbose]
Parameters
Table A-27 srvctl add vip Command Parameters
Parameter
-node node_name
-address {VIP_name|
ip}/netmask [/if1[|
if2|...]]
Description
The name of the node on which you are adding the VIP.
This specification creates a traditional VIP node application on the specified node.
You can specify one
VIP_name
or address, along with an IPv4 netmask or IPv6 prefix length.
-netnum network_number
The network number from which VIPs are obtained. The default network number is 1.
-skip
Specify this parameter to skip checking the reachability of the VIP address.
-verbose
Verbose output
Note:
Usage Notes
• You cannot have multiple VIPs on the same net number (subnet or interface pair) on the same node.
• This command is only available with Oracle Clusterware.
Example
An example of this command is:
# srvctl add network -netnum 2 -subnet 192.168.16.0/255.255.255.0
# srvctl add vip -node node7 -address 192.168.16.17/255.255.255.0 -netnum 2
The first command creates a network number,
2
, and the second command adds a VIP to this network. You can specify the network number after the
-netnum
parameter in other SRVCTL commands.
Server Control Utility Reference A-51
SRVCTL Command Reference
srvctl config vip
Displays all VIPs on all networks in the cluster except for user VIPs.
Syntax
srvctl config vip {-node node_name | -vip vip_name}
Parameters
Table A-28 srvctl config vip Command Parameters
Parameter
-node node_name
-vip vip_name
Description
Specify the node name.
Alternatively, you can specify the VIP name.
Usage Notes
This command is only available with Oracle Clusterware.
Example
This command returns output similar to the following:
$ srvctl config vip -node crmnode1
VIP exists: ipv4, ipv6, network number 1, hosting node adc2100252
srvctl disable vip
Disables a specific VIP.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl disable vip
command with the following syntax: srvctl disable vip -vip vip_name [-verbose]
Table A-29 srvctl disable vip Parameters
Parameter Description
The VIP name
-vip vip_name
Verbose output
-verbose
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Example
An example of this command is:
$ srvctl disable vip -vip vip1 -verbose
srvctl config volume
Displays the configuration for a specific volume or all volumes.
Syntax
srvctl config volume [-volume volume_name] [-diskgroup disk_group_name]
[-device volume_device]
Parameters
Table A-30 srvctl config volume Command Parameters
Parameter
-volume volume_name
-diskgroup
disk_group_name
-device volume_device
Description
Specify the name of the volume for which you want to view the configuration.
Specify the name of the disk group in which the volume resides for which you want to display the configuration.
Specify the path to the volume device for which you want to display the configuration.
Usage Notes
• If you do not specify any of the optional parameters, then SRVCTL displays the configuration information for all volumes.
• If you specify only the
-volume
parameter, then SRVCTL displays the configuration for all volumes with that name, regardless of the diskgroup.
• If you specify only the
-diskgroup
parameter, then SRVCTL displays the configuration information for the volumes that reside in the disk group that you specify.
• If you specify only the
-device
parameter, then SRVCTL displays the configuration information for the volume matching that device specifier.
• If you specify the
-diskgroup
and
-device
parameters, then SRVCTL displays the configuration information for the volume device that resides in the disk group that you specify.
• This command is only available with Oracle Clusterware.
Examples
This command returns information similar to the following:
$ srvctl config volume -device /dev/asm/volume1-123
Server Control Utility Reference A-53
SRVCTL Command Reference
Diskgroup Name: DG1
Volume Name : VOL1
Volume Device : /dev/asm/volume1-123
Volume is enabled.
Volume is enabled on nodes:
Volume is disabled on nodes:
If you do not specify any parameters, then SRVCTL returns configuration information for all volumes, similar to the following:
$ srvctl config volume
Diskgroup name: DG1
Volume name: VOL1
Volume device: /dev/asm/volume1-123
Volume is enabled.
Volume is enabled on nodes:
Volume is disabled on nodes:
Diskgroup name: DG1
Volume name: VOL2
Volume device: /dev/asm/volume2-456
Volume is enabled.
Volume is enabled on nodes:
Volume is disabled on nodes:
srvctl disable volume
Disables Oracle Clusterware management for a specific volume or all volumes.
This command allows a volume device to be stopped by operating on the Oracle
Clusterware resource for the volume. This command does not stop volume device.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl disable volume
command with the following syntax: srvctl disable volume {-volume
volume_name
-diskgroup
disk_group_name
|
-device
volume_device
}
Table A-31 srvctl disable volume Parameters
Parameter
-volume volume_name
Description
Specify the name of the volume that you want to disable. This parameter is required.
-diskgroup disk_group_name
Specify the name of the disk group in which the volume that you want to disable resides.
-device volume_device
Specify the path to the volume device that you want to disable.
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Usage Notes
• You must specify a particular volume that you want to disable. You can specify a volume that resides in either a particular disk group or on a particular volume device.
Example
The following example disables a volume named
VOLUME1
that resides in a disk group named
DATA
:
$ srvctl disable volume -volume VOLUME1 -diskgroup DATA
srvctl downgrade database
The srvctl downgrade database
command downgrades the configuration of a database and its services from its current version to the specified lower version.
Syntax and Parameters
Use the srvctl downgrade database
command as follows: srvctl downgrade database -db db_unique_name -oraclehome Oracle_home
-targetversion to_version
Table A-32 srvctl downgrade database Parameters
Parameter Description
Unique name for the database
-db db_unique_name
The path to the
ORACLE_HOME
-oraclehome Oracle_home
The version to which to downgrade
-targetversion to_version
enable
The srvctl enable
command enables the specified object so that it can run under
Oracle Clusterware for automatic startup, failover, or restart.
The Oracle Clusterware application supporting the object may be up or down to use this function. The default value is enable
. If the object is already enabled, then
SRVCTL returns a message advising you that the object is enabled. Enabled objects can be started, and disabled objects cannot be started.
When you run the enable
command, the object is enabled and available to run under
Oracle Clusterware for automatic startup, failover, or restart. Additionally, you can run the srvctl start
command on an enabled object. If you specify
-instance
instance_name
or
-node node_name
, then SRVCTL only enables the object on the specified instance or node.
If you do not specify
-instance instance_name
or
-node node_name
, then the enable action applies to the object that you specified, globally, on all nodes in the cluster and also removes any per-node enable settings. Any object you enable globally is also enabled on any nodes you add to the cluster in the future.
Server Control Utility Reference A-55
SRVCTL Command Reference
Enabling an object globally is different from enabling an object, individually, on each node in the cluster. For example, if you enable a database on several nodes, individually, in a cluster, then, when you run the srvctl start database command, the database starts only on nodes where the database is enabled. If, however, you enable the database globally, then the srvctl start database command starts the database on all nodes on which it is configured to run.
Table A-33 srvctl enable Summary
Command
Description
Enables the database resource
Enables a specified disk group on a number of specified nodes
Enables the instance
srvctl enable listener srvctl enable nodeapps
Enables a listener
Enables node applications and GSD
srvctl enable ons srvctl enable scan
srvctl enable scan_listener srvctl enable service
Enables the Oracle Notification Service daemon
Enables SCAN VIPs
Enables SCAN listeners
Enables a service
Enables a VIP
Enables a volume
srvctl enable database
Enables a cluster database and its instances.
Syntax and Parameters
Use the srvctl enable database
command with the following syntax: srvctl enable database -db
db_unique_name
[-node
node_name
]
Table A-34 srvctl enable database Parameters
Parameter Description
Database name
-db database_name
-node node_name
Example
An example of this command is:
$ srvctl enable database -db mydb1
The name of the node for which the database resource should be enabled
Note:
This parameter can be used only with Oracle
Clusterware.
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srvctl enable diskgroup
Enables a specific disk group on a number of specified nodes.
Syntax and Parameters
Use the srvctl enable diskgroup
command with the following syntax: srvctl enable diskgroup -diskgroup
diskgroup_name
[-node "
node_list
"]
Table A-35 srvctl enable diskgroup Parameters
Parameter Description
The Oracle ASM disk group name
-diskgroup diskgroup_name
-nodelist node_list
Comma-delimited list of node names on which to enable the disk group
This parameter is only available with Oracle
Clusterware.
Example
An example of this command is:
$ srvctl enable diskgroup -diskgroup diskgroup1 -node "mynode1,mynode2"
srvctl enable instance
Enables an instance for an Oracle RAC database. If you use this command to enable all instances, then the database is also enabled.
Note:
• This command is only available with Oracle Clusterware and Oracle
RAC.
• If you run this command on an Oracle RAC One Node database, then the command returns an error instructing you to use the database
noun, instead.
Syntax and Parameters
Use the srvctl enable instance
command with the following syntax: srvctl enable instance -db
db_unique_name
-instance "
instance_name_list
"
Table A-36 srvctl enable instance Parameters
Parameter Description
Unique name for the database
-db db_unique_name
Server Control Utility Reference A-57
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Table A-36 (Cont.) srvctl enable instance Parameters
Parameter Description
Comma-delimited list of instance names.
-instance "instance_name_list"
Example
An example of this command is:
$ srvctl enable instance -db crm -instance "crm1,crm2"
srvctl enable listener
Enables a listener resource.
Syntax and Parameters
Use the srvctl enable listener
command with the following syntax: srvctl enable listener [-listener
listener_name
] [-node
node_name
]
Table A-37 srvctl enable listener Parameters
Parameter
-listener listener_name
-node node_name
Description
Name of a listener resource. If you do not specify this parameter, the name of the listener defaults to
LISTENER
Name of a cluster node
Note:
This parameter can be used only with Oracle
Clusterware.
Example
To enable the listener named listener_crm
on the node named node5
, use the following command:
$ srvctl enable listener -listener listener_crm -node node5
srvctl enable nodeapps
Enables the node applications on all nodes in the cluster.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl enable nodeapps
command with the following syntax: srvctl enable nodeapps [-gsdonly] [-adminhelper] [-verbose]
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Table A-38 srvctl enable nodeapps Parameters
Parameter Description
Enable only the GSD daemon
-gsdonly
-adminhelper
Enable the Administrator helper only
Verbose output
-verbose
Example
An example of this command is:
$ srvctl enable nodeapps -gsdonly -verbose
srvctl enable ons
Enables the Oracle Notification Service daemon.
Note:
This command is only available with Oracle Restart.
Syntax and Parameters
Use the srvctl enable ons
command with the following syntax: srvctl enable ons [-verbose]
The only parameter for this command is
-verbose
, which indicates that verbose output should be displayed.
Example
An example of this command is:
$ srvctl enable ons
srvctl enable scan
Enables all SCAN VIPs, by default, or a specific SCAN VIP identified by its
ordinal_number
.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl enable scan
command with the following syntax: srvctl enable scan [-scannumber
ordinal_number
]
Server Control Utility Reference A-59
SRVCTL Command Reference
The only parameter available for this command is
-scannumber ordinal_number
, which identifies one of the three SCAN VIPs, and takes a range of values from 1 to 3.
Example
An example of this command is:
$ srvctl enable scan -scannumber 1
srvctl enable scan_listener
Enables all SCAN listeners, by default, or a specific listener identified by its
ordinal_number
.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl enable scan_listener
command with the following syntax: srvctl enable scan_listener [-scannumber
ordinal_number
]
The only parameter available for this command is
-scannumber ordinal_number
, which identifies one of three SCAN listeners, and takes a range of values from 1 to 3.
Example
An example of this command is:
$ srvctl enable scan_listener -scannumber 1
srvctl enable service
Enables a service for Oracle Clusterware. Enabling an entire service also affects the enabling of the service over all of the instances by enabling the service at each one.
When the entire service is already enabled, an srvctl enable service
operation does not affect all of the instances and enable them. Instead, this operation returns an error. Therefore, you cannot always use the entire set of service operations to manipulate the service indicators for each instance.
Syntax and Parameters
Use the srvctl enable service
command with the following syntax: srvctl enable service -db
db_unique_name
-service "
service_name_list
"
[-instance instance_name | -node
node_name
]
Table A-39 srvctl enable service Parameters
Parameter Description
Unique name for the database
-db db_unique_name
Comma-delimited list of service names
-service "service_name_list"
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Table A-39 (Cont.) srvctl enable service Parameters
Parameter
-instance instance_name
-node node_name
Description
Name of the database instance where you want the service to run
Use this parameter for administrator-managed databases
Note:
This parameter can be used only with Oracle
Clusterware and Oracle RAC.
Name of the node where you want the service to run
Use this parameter for policy-managed databases
Note:
This parameter can be used only with Oracle
Clusterware and Oracle RAC.
Examples
The following example globally enables a service:
$ srvctl enable service -db crm -service crm
The following example enables a service to use a preferred instance:
$srvctl enable service -db crm -service crm -instance crm1
srvctl enable vip
Enables a specific VIP.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl enable vip
command with the following syntax: srvctl enable vip -vip vip_name [-verbose]
Table A-40 srvctl enable vip Parameters
Parameter Description
The VIP name
-vip vip_name
Verbose output
-verbose
Example
The following command enables a VIP named crm1-vip
:
$ srvctl enable vip -vip crm1-vip -verbose
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SRVCTL Command Reference
getenv
srvctl enable volume
Enables Oracle Clusterware management for a specific volume or all volumes.
This command allows a volume device to be started by operating on the Oracle
Clusterware resource for the volume. This command does not start the volume device, and is different from the SQL command
ALTER DISKGROUP ENABLE VOLUME
or the
ASMCMD command volenable
, because these two commands bring the volume device online, in a running state, making the volume device accessible.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl enable volume
command with the following syntax: srvctl enable volume {-volume
volume_name
-diskgroup
disk_group_name
|
-device
volume_device
}
Table A-41 srvctl enable volume Parameters
Parameter
-volume volume_name
Description
Specify the name of the volume that you want to enable. This parameter is required.
-diskgroup disk_group_name
-device volume_device
Specify the name of the disk group in which the volume that you want to enable resides.
Specify the path to the volume device that you want to enable.
Usage Notes
• You must specify a particular volume that you want to enable. You can specify a volume that resides in either a particular disk group or on a particular volume device.
Example
The following example enables a volume named
VOLUME1
that resides in a disk group named
DATA
:
$ srvctl enable volume -volume VOLUME1 -diskgroup DATA
Gets and displays values for the environment variables from the configuration file.
Use SRVCTL with the setenv
, getenv
, and unsetenv
verbs to administer the environment configurations for databases, instances, services, and node applications.
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Table A-42 srvctl getenv Summary
Command
srvctl getenv database srvctl getenv listener
srvctl getenv nodeapps srvctl getenv vip
Description
Gets the database environment values
Gets the listener environment values
Gets the node application environment values
Gets the service environment values
srvctl getenv database
Displays the values for environment variables associated with a database.
Syntax and Parameters
Use the srvctl getenv database
command with the following syntax: srvctl getenv database -db
db_unique_name
[-envs "
name_list
"]
Table A-43 srvctl getenv database Parameters
Parameter Description
Unique name for the database
-db db_unique_name
-envs "name_list"
Comma-delimited list of the names of environment variables
If this parameter is not specified, then the values of all environment variables associated with the database are displayed.
Example
The following example gets the environment configuration for the
CRM
database:
$ srvctl getenv database -db crm
srvctl getenv listener
Gets the environment variables for the specified listener.
Syntax and Parameters
Use the srvctl getenv listener
command with the following syntax: srvctl getenv listener [-listener
listener_name
] [-envs "
name_list
"]
Table A-44 srvctl getenv listener Parameters
Parameter
-listener listener_name
Description
Listener name
If this parameter is not specified, the name of the listener defaults to
LISTENER
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Table A-44 (Cont.) srvctl getenv listener Parameters
Parameter
-envs "name_list"
Description
Comma-delimited list of the names of environment variables
If this parameter is not specified, then the values of all environment variables associated with the listener are displayed.
Example
The following example lists all environment variables specified for the default listener:
$ srvctl getenv listener
srvctl getenv nodeapps
Gets the environment variables for the node application configurations.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl getenv nodeapps
command with the following syntax: srvctl getenv nodeapps [-viponly] [-onsonly] [-envs "
name_list
"]
Table A-45 srvctl getenv nodeapps Parameters
Parameter Description
Displays the VIP address configuration
-viponly
Displays the Oracle Notification Service configuration
-onsonly
-envs "name_list"
Comma-delimited list of the names of environment variables
If this parameter is not specified, then SRVCTL displays the values of all environment variables associated with the node applications.
Example
The following example lists all environment variables for the node applications:
$ srvctl getenv nodeapps -viponly
srvctl getenv vip
Gets the environment variables for the specified VIP.
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SRVCTL Command Reference
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl getenv vip
command with the following syntax: srvctl getenv vip -vip
vip_name
[-envs "
name_list
"] [-verbose]
Table A-46 srvctl getenv vip Parameters
Parameter Description
The name of the VIP
-vip vip_name
-envs "name_list"
Comma-delimited list of the names of environment variables
If this parameter is not specified, then the values of all environment variables associated with the VIP are displayed.
Verbose output
-verbose
Example
The following example lists all environment variables for the specified VIP:
$ srvctl getenv vip -vip node1-vip
Enables you to modify the instance configuration without removing and adding
Oracle Clusterware resources.
Using modify
preserves the environment in the OCR configuration that would otherwise need to be reentered. The configuration description is modified in the OCR configuration, and a new Oracle Clusterware profile is generated and registered. The change takes effect when the application is next restarted.
Table A-47 srvctl modify Summary
Command
Description
Modifies the configuration for a database
Modifies the configuration for an instance
Modifies the listener configuration
Modifies the configuration for a network
Modifies the configuration for a node application
Modifies the network configuration for the Oracle Notification
Service daemon
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Table A-47 (Cont.) srvctl modify Summary
Command
srvctl modify scan srvctl modify scan_listener
Description
Modifies the SCAN VIP configuration to match that of a specific
SCAN VIP
Updates the SCAN listener configuration to match that of the current SCAN VIP configuration
Modifies the configuration for a service
Modifies a specific server pool
Modifies the VIP to use a different IP address type
srvctl modify database
Modifies the configuration for a database.
Syntax
srvctl modify database -db db_unique_name [-eval] [-dbname db_name]
[-instance instance_name] [-oraclehome oracle_home] [-user user_name]
[-server server_list] [-timeout timeout] [-domain db_domain]
[-spfile spfile] [-pwfile password_file_path]
[-role {PRIMARY|PHYSICAL_STANDBY|LOGICAL_STANDBY|SNAPSHOT_STANDBY}]
[-startoption start_options] [-stopoption stop_options]
[-policy {AUTOMATIC | MANUAL | NORESTART}]
[-serverpool "server_pool_name" [-node node_name]]
[-pqpool pq_server_pool] [{-diskgroup "diskgroup_list" | -nodiskgroup}]
[-acfspath "acfs_path_list"] [-css_critical {yes | no}] [-cpucount cpu_count]
[-memorytarget memory_target] [-maxmemory max_memory]
[-cpucap cpu_cap] [-defaultnetnum network_number] [-force]
Parameters
Table A-48 srvctl modify database Parameters
Parameter Description
-db db_unique_name
Unique name for the database.
-eval
Use this parameter to hypothetically evaluate the impact of the command on the system.
Note:
You can only use this parameter with a policy-managed database.
-dbname db_name
-instance
instance_name
-oraclehome
oracle_home
The name of the database, if it is different from the unique name given by the
-db
parameter.
Instance name prefix; this parameter is required for administratormanaged Oracle RAC One Node databases.
The path for the Oracle database home directory.
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Table A-48 (Cont.) srvctl modify database Parameters
Parameter
-user user_name
-server
server_list
-timeout timeout
-domain db_domain
-spfile spfile
-pwfile
password_file_path
Description
The name of the user that owns the Oracle home directory.
Note:
If you specify the
-user parameter, then you must run this command in privileged mode.
List candidate servers for Oracle RAC One Node databases.
Note:
You can use this parameter only with administratormanaged Oracle RAC One Node databases. If your Oracle RAC
One Node database is policy managed, you cannot use this parameter.
Online database relocation timeout, in minutes, for Oracle RAC
One Node databases. The default is
30
.
The domain for the database.
Note:
You must use this parameter if you set the
DB_DOMAIN initialization parameter for the database.
The path name of the database server parameter file.
Enter the full path to the location of the password file.
The role of the database in an Oracle Data Guard configuration.
The default is
PRIMARY
.
-role {PRIMARY |
PHYSICAL_STANDBY |
LOGICAL_STANDBY |
SNAPSHOT_STANDBY}
-startoption
start_options
-stoption
stop_options
Startup options for the database, such as
OPEN
,
MOUNT
, and
NOMOUNT
. The default value is
OPEN
.
Notes:
• For multi-word startup options, such as read only
and read write
, separate the words with a space and enclose in double quotation marks (
""
). For example,
"read only"
.
• When performing a switch-over in an Oracle Data Guard configuration, the
-startoption
for a standby database that becomes a primary database is always set to
OPEN
after the switchover.
Stop options for the database, such as
NORMAL
,
TRANSACTIONAL
,
IMMEDIATE
, and
ABORT
.
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Table A-48 (Cont.) srvctl modify database Parameters
Parameter
-policy {AUTOMATIC
| MANUAL |
NORESTART}
Description
Management policy for the database.
•
AUTOMATIC
(default): The database is automatically restored to its previous running condition (started or stopped) upon restart of the database host computer.
•
MANUAL
: The database is never automatically restarted upon restart of the database host computer. A
MANUAL
setting does not prevent Oracle Clusterware from monitoring the database while it is running and restarting it if a failure occurs.
•
NORESTART
: Similar to the
MANUAL
setting, the database is never automatically restarted upon restart of the database host computer. A
NORESTART
setting, however, never restarts the database even if a failure occurs.
-serverpool
"server_pool_name"
[-pqpool
"pq_pool_name"]
Specify the name of a server pool used to control database placement. If you do not specify this parameter, then it defaults to the Generic server pool.
You can optionally also specify the name of a parallel query server pool to be used by the database.
Notes:
• This parameter can only be used with Oracle Clusterware.
You can use this parameter with the
-node
parameter but the server pool must have
MAX_SIZE=1
and exactly one configured server (the one you specify in
-node
).
• After you add server pools, you can assign services to them using the
command.
-node node_name
-diskgroup
"disk_group_list"
-acfspath
"acfs_path_list"
Node name on which you want to register a noncluster, or single instance, Oracle database.
Note:
This parameter can be used only with Oracle Clusterware and can be used with the
-serverpool
parameter to create a policy-managed, noncluster database.
Comma-delimited list of Oracle ASM disk groups if database uses
Oracle ASM storage.
A single Oracle ACFS path or a comma-delimited list of Oracle
ACFS paths enclosed in double quotation marks (
""
) where the database's dependency is set.
Use this parameter to create dependencies on Oracle ACFS file systems other than
ORACLE_HOME
, such as for when the database uses
ORACLE_BASE
on a file system that is different from the
ORACLE_HOME
file system.
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Table A-48 (Cont.) srvctl modify database Parameters
Parameter
-css_critical {YES
| NO}
Description
You can add weight to a service by setting this parameter to
YES
.
In the event of a node failure within the cluster, Oracle
Clusterware will evict the node with the least amount of weight, ensuring that critical services remain available.
Note:
You can use this parameter only on an administratormanaged node. Should the node become policy managed, at some point, this parameter will no longer apply.
-cpucount
cpu_count
Specify the number of CPUs. The default value is 0.
-memorytarget
memory_target
-maxmemory
max_memory
-cpucap cpu_cap
Specify the target memory, in MB, to be allocated for the database.
The default is 0.
Specify the maximum memory, in MB, to be allocated for the resource. If you specify
-memorytarget
but not
-maxmemory
, then
-maxmemory
will be the default value of 0. Both
maxmemory
and
-memorytarget
are validated as long as
memorytarget
is less than or equal to
-maxmemory
.
Specify a percentage from 1 to 100 that is the maximum utilization of the workload CPUs the database requires. The default is 0.
-defaultnetnum
network_number
Specify a network number to which services will default in the event you do not specify a network number when you add a service.
See Also::
•
Oracle Data Guard Concepts and Administration
for more information about database roles
•
SQL*Plus User's Guide and Reference
for more information about database startup options
•
SQL*Plus User's Guide and Reference
for more information about database shutdown options
Usage Notes
• The srvctl modify database
command can convert administrator-managed databases to policy-managed databases. For a running administrator-managed database, if the server list is supplied, then the node where the database is running must be on that list. The instance name prefix cannot be modified after running the srvctl add database
command.
• You cannot change the management policy from
AUTOMATIC
(using the
-policy parameter) for Oracle RAC One Node databases. Any attempt to do so results in an error message. The same is true for the
-node
parameter, which is used to change the node on which a noncluster database runs.
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• For policy-managed Oracle RAC One Node databases, you can use the
serverpool
parameter to move an Oracle RAC One Node database between server pools but you can only specify one server pool. Specifying a list of server pools returns an error.
Examples
The following example changes the role of a database to a logical standby:
$ srvctl modify database -db crm -role logical_standby
The following example directs the racTest
database to use the
SYSFILES
,
LOGS
, and
OLTP
Oracle ASM disk groups:
$ srvctl modify database -db racTest -diskgroup "SYSFILES,LOGS,OLTP"
srvctl modify instance
For an administrator-managed database, this command modifies the configuration for a database instance from its current node to another node. For a policy-managed database, this command defines an instance name to use when the database runs on the specified node.
Syntax
srvctl modify instance -db db_unique_name -instance instance_name
-node node_name
Parameters
Table A-49 srvctl modify instance Command Parameters
Parameter
-database
db_unique_name
-instance
instance_name
Description
Specify the unique name for the database.
-node node_name
Specify the database instance name.
Notes:
• If you are modifying a policy-managed database instance, then the instance name must contain an underscore (
_
), such as pmdb1_1
.
• If you specify an instance name that has never been started before, and is not of the form
prefix_number
, then you may have to assign an instance number, undo, and redo in the SPFILE.
Name of the node on which to run the instance. You can set the value of this parameter to
""
only for a policy-managed database.
Usage Notes
You cannot use this command to rename or relocate a running instance.
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Examples
The following example to changes the configuration of an administrator-managed database, amdb
, so that the database instance, amdb1
, runs on the specified node, mynode
:
$ srvctl modify instance -db amdb -instance amdb1 -node mynode
The following example causes the policy-managed database pmdb
, when and if it runs on mynode
, to use the instance name pmdb1
:
$ srvctl modify instance -db pmdb -instance pmdb1_1 -node mynode
The following example removes the directive established by the previous example:
$ srvctl modify instance -db pmdb -instance pmdb1_1 -node ""
srvctl modify listener
Changes the Oracle home directory from which the listener runs, the name of the operating system user who owns Oracle home directory from which the listener runs, the listener endpoints, or the public subnet on which the listener listens, either for the default listener, or a specific listener, that is registered with Oracle Restart or with
Oracle Clusterware.
If you want to change the name of a listener, then use the srvctl remove listener
and
commands.
Syntax and Parameters
Use the srvctl modify listener
command with the following syntax: srvctl modify listener [-listener listener_name] [-oraclehome oracle_home]
[-user
user_name
] [-netnum
network_number
]
[-endpoints "[TCP:]port_list[/IPC:key][/NMP:pipe_name][/TCPS:s_port][/SDP:port]"]
Table A-50 srvctl modify listener Parameters
Parameter
-listener listener_name
-oraclehome oracle_home
-user user_name
Description
The name of the listener.
If you do not specify this parameter, then SRVCTL uses the default name
LISTENER
.
When this parameter is specified, SRVCTL moves the listener to run from the specified Oracle home.
Note:
When using this parameter, the command should be run as privileged user to enable SRVCTL to update resource ownership corresponding to the new
ORACLE_HOME
owner
The name of the operating system user who will own the specified Oracle listener
Note:
This parameter can be used only with Oracle
Clusterware.
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Table A-50 (Cont.) srvctl modify listener Parameters
Parameter
-netnum network_number
-endpoints "[TCP:]port_list [/
IPC:key][/NMP:pipe_name]
[/TCPS:s_port][/SDP:port]"
Description
This parameter changes the public subnet on which the listener listens.
Note:
You should always have at least one listener on the default network. Do not use this parameter to change the network of the only listener that listens on the default network.
Protocol specifications for the listener.
port_list
is comma-delimited list of port numbers.
Note:
You can modify this attribute using Online
Resource Attribute Modification.
Example
The following example changes the TCP ports for the default listener:
$ srvctl modify listener -endpoints "TCP:1521,1522"
srvctl modify network
Modifies the subnet, network type, or IP address type for a network.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl modify network
command with one of the following syntax models: srvctl modify network [-netnum
network_number
] [-subnet subnet/netmask
[/if1[|if2|...]]] [-nettype network_type | -iptype {ipv4 | ipv6 | both]}
[-pingtarget "ping_target_list"] [-verbose]
Table A-51 srvctl modify network Parameters
Parameter Description
Specify a network number. The default is 1.
-netnum network_number
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Table A-51 (Cont.) srvctl modify network Parameters
Parameter
-subnet subnet/netmask
[/if1[|if2|...]]
-nettype network_type
Description
Specifies a subnet number for the public network. The netmask and interfaces specified, if any, change those of the network you are modifying. If you specify an IPv6 subnet, then enter a prefix length, such as 64, in place of
netmask
. If you do not specify any interface names, then the VIPs use any interface on the given subnet.
If you are changing the network type using the
-nettype parameter, then you must specify either an existing IPv4 or
IPv6 network using the
-subnet
parameter. Additionally, the subnet and netmask you specify in the
-subnet parameter do not change those of the network you are modifying.
Specify the network type: static
, dhcp
, autoconfig
, or mixed
.
The type of IP address: ipv4
, ipv6
, or both
.
-iptype ip_type
-pingtarget
"ping_target_list"
Specify a comma-delimited list of IP addresses or host names to ping.
Verbose output.
-verbose
Usage Notes
• On Linux and UNIX systems, you must be logged in as root
and on Windows, you must be logged in as a user with Administrator privileges to run this command.
• You can modify the IP address type for a network from IPv4 to IPv6, or from IPv6 to IPv4.
See Also:
Oracle Clusterware Administration and Deployment Guide
for more information
• If you specify static
for the network type, then you must provide the virtual IP
address using the srvctl add vip
command.
• If you specify dhcp
for the network type, then the VIP agent obtains the IP address from a DHCP server.
• If you specify autoconfig
for the network type, then the VIP agent generates a stateless IPv6 address for the network. You can only use this parameter for IPv6 networks. If the subnet/netmask specification is not for an IPv6 address, then
SRVCTL returns an error.
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• If you change a network from static
to mixed
, then you must first configure
GNS, so that the dynamic addresses obtained can have names registered for them.
• If you specify mixed
for the network type, then the VIP resource uses both a static
IP address and an IP address obtained dynamically, either DHCP or autoconfig.
• If you specify mixed_autoconfig
for the network type, then the VIP resource retains the static IP configuration and either obtains an IP address from a DHCP server for an IPv4 network specification or generates a stateless auto-configured
IP address for an IPv6 network specification.
Examples
The following example changes the subnet number, netmask, and interface list:
# srvctl modify network -subnet 192.168.2.0/255.255.255.0/eth0
The following example changes the second network to DHCP:
# srvctl modify network -netnum 2 -nettype dhcp
The following example adds an IPv6 subnet and netmask to the default network:
# srvctl modify network -subnet 2606:b400:400:18c0::/64
The following example removes the IPv4 configuration from a network:
# srvctl modify network -iptype ipv6
srvctl modify nodeapps
Modifies the configuration for a node application.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl modify nodeapps
command with one of the following syntax models, specifying either a specific node and VIP or a specific subnet and netmask: srvctl modify nodeapps {[-node
node_name
-address {vip_name|
vip_address
}/
netmask[/if1[|if2|...]] [-skip]] [-nettype network_type] [-emport
em_port
]
[-onslocalport ons_local_port] [-onsremoteport ons_remote_port]
[-remoteservers host:[port][,host:port,...]] [-verbose]
[-clientdata file] [-pingtarget "ping_target_list"] srvctl modify nodeapps [-subnet
subnet
/netmask[/if1[|if2|...]]
[-nettype network_type] [-emport
em_port
]
[-onslocalport ons_local_port] [-onsremoteport ons_remote_port]
[-remoteservers host:[port][,host:port,...]] [-verbose]
[-clientdata file] [-pingtarget "ping_target_list"]
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Table A-52 srvctl modify nodeapps Parameters
Parameter
-node node_name
Description
The name of the node on which the node application you want to modify resides.
-address {vip_name|vip_address}/
netmask[/if1[|if2|...]]
-skip
Node-level virtual IP name or address. The address specified by name or IP must match the subnet number of the default network.
Note:
This parameter must be used for upgrade configurations and new non-DHCP configurations
Specify this parameter to skip checking the reachability of the VIP address.
-subnet subnet/netmask
[/if1[|if2|...]]
-nettype network_type
-emport em_port
-onslocalport ons_local_port
-onsremoteport ons_remote_port
-remoteservers host:port,
[host:port,...]
Specifies a subnet number for the public network.
The netmask and interfaces specified, if any, change those of the default network.
Additionally, if you specify the
netmask
option, then you need only specify it for the first node on each network.
Specifies the network server type, such as static
, dhcp
, or mixed
.
Local port on which Oracle Enterprise Manager listens.
Note:
You can modify this attribute using Online
Resource Attribute Modification.
Port on which the Oracle Notification Service daemon listens for local client connections.
Notes:
• The local port and remote port must each be unique.
• You can modify the local port while the resource remains online, without restarting the resource.
Port on which the Oracle Notification Service daemon listens for connections from remote hosts.
Notes:
• The local port and remote port must each be unique.
• You can modify the remote port while the resource remains online, without restarting the resource.
List of
host:port
pairs of remote hosts that are part of the Oracle Notification Service network but are not part of the cluster. If you do not specify a port
for a remote host, then the utility uses the value you specified for
ons_remote_port
.
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Table A-52 (Cont.) srvctl modify nodeapps Parameters
Parameter
-clientdata file
-pingtarget "pingtarget_list"
Description
Specify the file with a wallet to import, or an empty string to delete a wallet used for SSL to secure Oracle Notification Service communication.
Specify a comma-separated list enclosed in double quotation marks (
""
) of IPs or host names to ping.
Verbose output.
-verbose
Example
The following example changes the nodeapps resource on mynode1
to use the application VIP of 100.200.300.40 with a subnet mask of 255.255.255.0 on the network interface eth0
:
$ srvctl modify nodeapps -node mynode1 -addr 100.200.300.40/255.255.255.0/eth0
srvctl modify ons
Modifies the ports used by the Oracle Notification Service daemon that is registered with Oracle Restart.
Note:
This command is available only with Oracle Restart.
Syntax and Parameters
Use the srvctl modify ons
command with the following syntax: srvctl modify ons [-onslocalprt ons_local_port] [-onsremoteport
ons_remote_port
]
[-emport em_port] [-remoteservers
host
[:
port
][,
host
[:
port
]][...]] [-verbose]
Table A-53 srvctl modify ons Parameters
Parameter
-onslocalport ons_local_port
Description
The Oracle Notification Service daemon listening port for local client connections
Note:
The local port and remote port must each be unique.
-onsremoteport
ons_remote_port
The Oracle Notification Service daemon listening port for connections from remote hosts
Note:
The local port and remote port must each be unique.
-remoteservers host[:port]
[,host[:port]][...]]
A list of
host:port
pairs of remote hosts that are part of the Oracle Notification Service network but are not part of the Oracle Clusterware cluster
Note:
If you do not specify
port
for a remote host, then the utility uses
ons_remote_port
.
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Table A-53 (Cont.) srvctl modify ons Parameters
Parameter Description
Display verbose output
-verbose
srvctl modify scan
Modifies the number of SCAN VIPs to match the number of IP addresses returned by looking up the
scan_name
you specify in DNS.
You use this command when DNS was modified to add, change, or remove IP addresses, and now you must adjust the Oracle Clusterware resource configuration to match.
Syntax
srvctl modify scan -scanname scan_name [-netnum network_number]
Parameters
Table A-54 srvctl modify scan Command Parameters
Parameter
-scanname
scan_name
-netnum
network_number
Description
Identifies the SCAN name that resolves to the SCAN VIPs that you want to modify.
Note:
You can modify this attribute using Online Resource
Attribute Modification.
The optional network number from which VIPs are obtained. If not specified, the VIPs are obtained from the same default network from which the nodeapps
VIP is obtained.
Example
Assume your system currently has a SCAN named scan_name1
, and it resolves to a single IP address in DNS. If you modify the SCAN scan_name1
in DNS to resolve to three IP addresses, then use the following command to create the additional SCAN
VIP resources:
$ srvctl modify scan -scanname scan_name1
srvctl modify scan_listener
Modifies the SCAN listener to match that of the SCAN VIP, or modifies the SCAN listener endpoints or service registration restrictions.
Syntax
srvctl modify scan_listener {-update | -endpoints [TCP:]port_list[:FIREWALL={ON|OFF}]
[/IPC:key]
[/NMP:pipe_name][/{TCPS|SDP|EXADIRECT}port_list[:FIREWALL={ON|OFF}]]"} [invitednodes node_list]
[-invitedsubnets subnet_list]
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Parameters
Table A-55 srvctl modify scan_listener Command Parameters
Parameter
-update
-endpoints
"[TCP:]port_list[:
FIREWALL={ON|OFF}]
[/IPC:key] [/
NMP:pipe_name][/
{TCPS|SDP|
EXADIRECT}port_lis
t[:FIREWALL={ON|
OFF}]]"]
Description
Use this parameter to update SCAN listener configuration to match the current SCAN VIP configuration. This parameter adds new resources or removes existing SCAN listener resources to match the number of SCAN VIP resources.
Protocol specifications for the SCAN listener. Use
port_list
to specify a comma-delimited list of TCP ports or listener endpoints.
You can also specify endpoints for TCPS, SDP, and EXADIRECT ports.
-invitednodes
node_list
-invitedsubnets
subnet_list
Use this parameter to specify a comma-delimited list of host names from outside the cluster that are allowed to register with the SCAN listener.
Use this parameter to specify a comma-delimited list of subnets from outside the cluster that are allowed to register with the
SCAN listener.
Example
Assume your system currently has a SCAN named scan_name1
, and you recently modified the DNS entry to resolve to three IP addresses instead of one. After running the srvctl modify scan
command to create additional SCAN VIP resources, use the following command to create Oracle Clusterware resources for the additional two
SCAN listeners to go with the two additional SCAN VIPs:
$ srvctl modify scan_listener -update
srvctl modify service
Modifies service configuration.
This command supports some online modifications to the service, such as:
• Moving a service member from one instance to another
• Performing online changes to service attributes from
DBMS_SERVICE
(for example, failover delay, runtime load balancing goal, and so on)
• Adding a new preferred or available instance
• Removing preferred or available instances for a service
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Caution:
Oracle recommends that you limit configuration changes to the minimum requirement and that you not perform other service operations while the online service modification is in progress.
Syntax and Parameters
Use one of the following forms of the srvctl modify service
command, depending on the task you want to perform, with the specified syntax:
To move a service from one instance to another:
srvctl modify service -db db_unique_name -service service_name
-oldinst old_instance_name -newinst new_instance_name [-force]
Note:
This form of the command is only available with Oracle Clusterware.
Table A-56 srvctl modify service Parameters for Moving a Service
Parameter Description
-db db_unique_name
Specify the unique name for the database.
-service
service_name
-oldinst
old_instance_name
-newinst
new_instance_name
-force
Specify a service name. If you do not specify a service name, then
SRVCTL moves all services.
Specify the name of the instance from which you want to move the service.
Specify the name of the instance to which you want to move the service.
Disconnects all sessions during stop or relocate service operations.
To change an available instance to a preferred instance for a service:
srvctl modify service -db db_unique_name -service service_name
-available avail_inst_name -toprefer [-force]
Note:
This form of the command is only available with Oracle Clusterware and does not accept placement parameters for Oracle RAC One Node databases.
Table A-57 srvctl modify service Parameters for Changing to a Preferred Instance
Parameter Description
-db db_unique_name
Specify the unique name for the database.
-service
service_name
Specify the name of the service you want to modify.
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Table A-57 (Cont.) srvctl modify service Parameters for Changing to a Preferred
Instance
Parameter
-available
available_inst_nam e
-toprefer
Description
Specify the name of the available instance you want to change.
-force
Specify this parameter to change the instance status to preferred.
Disconnect all sessions during stop or relocate service operations.
For planned operations, the user experience is best if using an
Oracle Connection Pool with FAN, and not forcing disconnect.
The FAN planned event causes the Oracle pool to drain the requests with no interruption to the users.
To change the available and preferred status for multiple instances:
srvctl modify service -db db_unique_name -service service_name
-modifyconfig -preferred "preferred_list" [-available "available_list"]
[-force]
Note:
This form of the command is only available with Oracle Clusterware and does not accept placement parameters for Oracle RAC One Node databases.
Table A-58 srvctl modify service Parameters for Changing Status of Multiple
Instances
Parameter Description
-db db_unique_name
Specify the unique name for the database.
Specify the name of the service you want to modify.
-service
service_name
-modifyconfig
-preferred
"preferred_instanc
e_list"
This parameter directs SRVCTL to use only the instances named for this service (unnamed instances already assigned to the service are removed).
Specify a comma-delimited list of preferred instances enclosed within double quotation marks ("").
-available
"available_instanc
e_list"
-force
Specify a comma-delimited list of available instances enclosed within double quotation marks ("").
Disconnect all sessions during stop or relocate service operations.
For planned operations, the user experience is best if using an
Oracle Connection Pool with FAN, and not forcing disconnect.
The FAN planned event causes the connection pool to drain the requests with no interruption to the users.
To modify other service attributes or to modify a service for Oracle Clusterware:
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SRVCTL Command Reference srvctl modify service -db db_unique_name -service service_name [-eval]
[-serverpool pool_name] [-cardinality {UNIFORM|SINGLETON}]
[-drain_timeout timeout] [-stopoption {NONE|IMMEDIATE|TRANSACTIONAL}]
[-pqservice pqsvc_name] [-pqpool pq_pool_list]
[-pdb pluggable_database] [-tafpolicy {BASIC|NONE}]
[-edition edition_name] [-role "[PRIMARY][,PHYSICAL_STANDBY]
[,LOGICAL_STANDBY][,SNAPSHOT_STANDBY]"] [-notification {TRUE|FALSE}]
[-dtp {TRUE|FALSE}] [-clbgoal {SHORT|LONG}] [-rlbgoal {NONE|SERVICE_TIME|
THROUGHPUT}]
[-failovertype {NONE|SESSION|SELECT|TRANSACTION}] [-failovermethod {NONE|BASIC}]
[-failoverrestore [NONE|LEVEL1]] [-failoverretry failover_retries]
[-failoverdelay failover_delay] [-policy {AUTOMATIC|MANUAL}]
[-sql_translation_profile profile_name] [-commit_outcome {TRUE|FALSE}]
[-retention retention_time] [-replay_init_time replay_initiation_time]
[-session_state {STATIC|DYNAMIC}] [-global_override] [-verbose] [-force]
Table A-59 srvctl modify service Parameters
Parameter Description
-db db_unique_name
Specify the unique name for the database.
-service
service_name
Specify the name of the service you want to modify.
-eval
-serverpool
pool_name
Use this parameter to hypothetically evaluate the impact of the command on the system.
Note:
You can only use this parameter with a policy-managed service.
The name of a server pool used when the database is policy managed.
Note:
This parameter can be used only with Oracle RAC and only for policy-managed databases.
-cardinality
{UNIFORM|
SINGLETON}
-drain_timeout
timeout
Specify the cardinality of the service, either
UNIFORM
(offered on all instances in the server pool) or
SINGLETON
(runs on only one instance at a time).
Note:
This parameter can be used only with Oracle Clusterware.
Specify the time, in seconds, allowed for resource draining to be completed. Accepted values are an empty string (""), 0, or any positive integer. The default value is an empty string, which means that this parameter is not set. If it is set to 0, then draining occurs, immediately.
The draining period is intended for planned maintenance operations. During the draining period, all current client requests are processed, but new requests are not accepted. When set on the service this value is used when the command line value is not set.
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Table A-59 (Cont.) srvctl modify service Parameters
Parameter
-stopoption {NONE|
IMMEDIATE|
TRANSACTIONAL}
Description
Specify the mode in which the service is stopped. If you set this parameter on the service, then this value is used if you do not set the value on the command line.
IMMEDIATE
permits sessions to drain before the service is stopped.
TRANSACTIONAL
permits sessions to drain for the amount of time specified in the
-drain_timeout
parameter. The service is stopped when the time limit is reached and any remaining sessions are terminated.
If you specify
NONE
, then no sessions are terminated.
The default is taken from the service setting, when specified on the service. Otherwise the default is
NONE
.
Note:
You must use the
-stopoption
parameter with the
force
parameter.
Specify a comma-delimited list of parallel query service names.
-pqservice
pqsvc_name
-pqpool
pq_pool_list
-pdb
pluggable_database
-tafpolicy {BASIC|
NONE}
Specify a comma-delimited list of parallel query server pool names.
Specify the name of a pluggable database (PDB).
Note:
You can specify a PDB property when you create or modify a service. The PDB property associates the service with the specified PDB. You can view the PDB property for a service by querying the ALL_SERVICES data dictionary view or, when using the SRVCTL utility, by running the srvctl config service command.
When create or modify a service with the specified PDB, SRVCTL does not check if the PDB exists. Before running this command, you must ensure that the PDB exists.
Specify the transaction failover (TAF) policy (for administratormanaged databases only).
-edition
edition_name
-role "[PRIMARY]
[,PHYSICAL_STANDBY
]
[,LOGICAL_STANDBY]
[,SNAPSHOT_STANDBY
]"
The initial session edition of the service.
When an edition is specified for a service, all subsequent connections that specify the service use this edition as the initial session edition. However, if a session connection specifies a different edition, then the edition specified in the session connection is used for the initial session edition.
SRVCTL does not validate the specified edition name. During connection, the connect user must have
USE
privilege on the specified edition. If the edition does not exist or if the connect user does not have
USE
privilege on the specified edition, then an error is raised.
The database modes for which the service should be started automatically. You can specify one or more roles in a commadelimited list.
Note:
The
-role
parameter is only used at database startup and by the Oracle Data Guard Broker. All manual service startup must specify the name of the service to be started by the user.
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Table A-59 (Cont.) srvctl modify service Parameters
Parameter
-notification
{TRUE|FALSE}
-dtp {TRUE|FALSE}
-clbgoal {SHORT|
LONG}
-rlbgoal {NONE|
SERVICE_TIME|
THROUGHPUT}
-failovertype
{NONE|SESSION|
SELECT|
TRANSACTION}
-failovermethod
{NONE|BASIC}
-failoverrestore
[NONE|LEVEL1]
-failoverretry
failover_retries
-failoverdelay
failover_delay
-policy
{AUTOMATIC|MANUAL}
sql_translation_pr ofile profile_name
-commit_outcome
{TRUE|FALSE}
Description
Specify a value of
TRUE
to enable Fast Application Notification
(FAN) for Oracle Call Interface (OCI) connections.
Specify
TRUE
to enable Distributed Transaction Processing for this service. This ensures that the service is offered at exactly one instance at a time for XA affinity.
Use this parameter to set a connection load balancing goal: set to
SHORT
if using runtime load balancing, set to
LONG
for long running connections, such as batch jobs or older SQL*Forms style.
Use this parameter to set a runtime load balancing goal. Set this parameter to
SERVICE_TIME
to balance connections by response time. Set this parameter to
THROUGHPUT
to balance connections by throughput.
Use this parameter to set the failover type.
To enable Application Continuity, set this parameter to
TRANSACTION
. To enable TAF, set this parameter to
SELECT
or
SESSION
.
Specify the TAF failover method (for backward compatibility only).
For Application Continuity, when you set the
failoverrestore
parameter, session states are restored before replaying. Use
LEVEL1
for ODP.NET and Java with Application
Continuity to restore the initial state.
For OCI applications using TAF or Application Continuity, setting
-failoverrestore
to
LEVEL1
restores the current state. If the current state differs from the initial state, then a TAF callback is required. This restriction applies only to OCI.
For Application Continuity and TAF, specify the number of attempts to connect after an incident.
For Application Continuity and TAF, specify the time delay (in seconds) between reconnect attempts per incident at failover.
Specify the service management policy.
Use this parameter to specify a SQL translation profile for a service that you are modifying after you have migrated applications from a non-Oracle database to an Oracle database.
If you want to set the SQL translation profile to a NULL value, then you must enter an empty string after the
-p
flag.
Note:
Before using the SQL translation feature, you must migrate all server-side application objects and data to the Oracle database.
Enable Transaction Guard; when set to
TRUE
, the commit outcome for a transaction is accessible after the transaction's session fails due to a recoverable outage.
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Table A-59 (Cont.) srvctl modify service Parameters
Parameter
-retention
retention_time
-replay_init_time
replay_initiation_ time
-session_state
{STATIC|DYNAMIC}
-global_override
–verbose
-force
Description
For Transaction Guard (with the
-commit_outcome
parameter set to
TRUE
); this parameter determines the amount of time (in seconds) that the commit outcome is retained in the database.
For Application Continuity; this parameter specifies the time, in seconds, from when the original request started. Application
Continuity will not replay after the specified amount of time has passed. This attribute avoids the unintentional replay of a request when a system is recovered after a long period. The default value is 300 (5 minutes).
For Application Continuity; this parameter specifies whether the session state that is not transactional is changed by the application. Oracle recommends a value of
DYNAMIC
for most applications. If you are unsure which value to use or you can customize the application, then use
DYNAMIC
.
STATIC
mode is on request for database-agnostic applications, that never change nontransactional state inside a request.
Override value to modify the global service attributes.
Use this parameter with the
-role
,
-policy
,
-notification
,
-failovertype
,
-failovermethod
,
-failoverdelay
,
failoverretry
and
-edition
parameters.
Display verbose output.
Force the modify operation, stopping the service on some nodes as necessary.
Usage Notes
• When performing online changes to service attributes (for example, failover delay,
Runtime Load Balancing Goal, and so on), the changes take effect only when the service is next (re)started.
• When a service configuration is modified so that a new preferred or available instance is added, the running state of the existing service is not affected.
However, the newly added instances will not automatically provide the service, until a srvctl start service
command is issued.
• When there are available instances for the service, and the service configuration is modified so that a preferred or available instance is removed, the running state of the service may change unpredictably:
– The service is stopped and then removed on some instances according to the new service configuration.
– The service may be running on some instances that are being removed from the service configuration.
– These services will be relocated to the next free instance in the new service configuration.
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Because of these considerations, when the online service is being modified, users may experience a brief service outage on some instances even if the instances are not being removed. Or users may experience a brief service outage on instances that are being removed from the service.
Examples
An example of moving a service member from one instance to another is:
$ srvctl modify service -db crm -service crm -oldinst crm1 -newinst crm2
An example of changing an available instance to a preferred instance is:
$ srvctl modify service -db crm -service crm -available crm1 -toprefer
The following command exchanges a preferred and available instance:
$ srvctl modify service -db crm -service crm -modifyconfig -preferred "crm1" \
-available "crm2"
Related Topics:
Oracle Data Guard Broker
Oracle Database SQL Translation and Migration Guide
srvctl modify srvpool
Modifies a server pool in a cluster. If minimum size, maximum size, and importance are numerically increased, then the CRS daemon may attempt to reassign servers to this server pool, if by resizing other server pools have comparatively lower minimum size and importance, to satisfy new sizes of this server pool.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl modify srvpool
command with the following syntax: srvctl modify srvpool -serverpool pool_name [-eval] [-importance importance]
[-min min_size] [-max max_size] [-servers "server_list"]
[-category "server_category"] [-verbose] [-force]
Table A-60 srvctl modify srvpool Parameters
Parameter Description
The name of the server pool to modify,
-serverpool pool_name
-eval
Use this parameter to hypothetically evaluate the impact of the command on the system.
The new importance of the server pool.
-importance importance
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Table A-60 (Cont.) srvctl modify srvpool Parameters
Parameter
-min min_size
Description
The new minimum size of the server pool. The default value is 0.
-max max_size
-servers "server_list"
The new maximum size of the server pool. A value of
-1
sets the server pool maximum size to
UNLIMITED
.
A comma-delimited list of candidate server names.
Note:
In Oracle Database 12c, servers are assigned to server pools according to the value of the
category
parameter.
Server category (or
""
for empty category value).
-category "server_category"
Display verbose output
-verbose
-force
Force the operation even though the utility stops some resource(s).
Example
The following example changes the importance rank to 0, the minimum size to 2, and the maximum size to 4 for the server pool srvpool1
:
$ srvctl modify srvpool -serverpool srvpool1 -importance 0 -min 2 -max 4
srvctl modify vip
Modifies IP address type but you can also use it to modify just the IP address.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl modify vip
command with the following syntax: srvctl modify vip -node node_name -address {VIP_name|ip}/netmask[/if1[|if2|...]]
[-netnum network_number] [-verbose]
Table A-61 srvctl modify vip Parameters
Parameter Description
The name of the node on which you are changing the VIP.
-node node_name
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Table A-61 (Cont.) srvctl modify vip Parameters
Parameter
-address {VIP_name|ip}/
netmask
[/if1[|if2|...]]
-netnum network_number
-verbose
Description
Use this parameter to change the configuration of an existing
VIP. If the VIP has an IPv4 address and the address you specify is IPv6, and the IP address type is set to both
and the network type is set to static
, then SRVCTL adds the IPv6 address to the existing IPv4 address of that resource.
You can specify one
VIP_name
or IP address, along with an
IPv4 netmask or IPv6 prefix length.
The optional network number from which VIPs are obtained.
If you do not specify this parameter, then the VIPs are obtained from the same default network from which the nodeapps
VIP is obtained.
Verbose output
Note:
You cannot have multiple VIPs on the same net number (subnet or interface pair) on the same node.
Example
The following example adds an IPv4 address to a VIP, if one does not already exist. If the VIP has an IPv4 address, then it is replaced with the new network specification.
# srvctl modify vip -node node7 -address 192.168.16.17/255.255.255.0 -netnum 2
The predict
command predicts what happens when a resource fails and cannot be restarted on the same node. This command does not make any modifications to the system.
Table A-62 srvctl predict Summary
Command
Description
Predicts the consequences of database failure
Predicts the consequences of diskgroup failure
Predicts the consequences of listener failure
srvctl predict network srvctl predict scan
Predicts the consequences of network failure
Predicts the consequences of SCAN failure
srvctl predict scan_listener srvctl predict service
Predicts the consequences of SCAN listener failure
Predicts the consequences of service failure
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Table A-62 (Cont.) srvctl predict Summary
Command
Description
Predicts the consequences of VIP failure
srvctl predict database
The srvctl predict database
command predicts what happens if the specified database fails.
Syntax and Parameters
Use the srvctl predict database
command with the following syntax: srvctl predict database -db db_unique_name [-verbose]
Table A-63 srvctl predict database Parameters
Parameter Description
Unique name for the database.
-db db_unique_name
Verbose output.
-verbose
Example
The following example predicts what happens if the database named racdb
fails: srvctl predict database -db racdb
srvctl predict diskgroup
Predicts the consequences of and Oracle ASM disk group failure.
Syntax and Parameters
Use the srvctl predict diskgroup
command with the following syntax: srvctl predict diskgroup -diskgroup diskgroup_name [-verbose]
Table A-64 srvctl predict diskgroup Parameters
Parameter
-diskgroup diskgroup_name
Description
The name of the Oracle ASM disk group for which you want to evaluate failure
Display verbose output.
-verbose
Example
An example of this command is:
$ srvctl predict diskgroup -diskgroup data
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srvctl predict listener
Predicts the consequences of listener failure.
Syntax and Parameters
Use the srvctl predict listener
command with the following syntax: srvctl predict listener listener_name [-verbose]
Table A-65 srvctl predict listener Parameters
Parameter
-listener listener_name
Description
Specify the name of the listener for which you want to predict the consequences of a failure.
Display verbose output.
-verbose
Example
An example of this command is:
$ srvctl predict listener -listener NODE3_CRMAPP_LISTENER
srvctl predict network
Predicts the consequences of network failure.
Syntax and Parameters
Use the srvctl predict network
command with the following syntax: srvctl predict network [-netnum network_number [-verbose]
Table A-66 srvctl predict network Parameters
Parameter
-netnum network_number
Description
Specify the network for which you want to evaluate failure. The default value is 1.
Display verbose output.
-verbose
Example
An example of this command is:
$ srvctl predict network -netnum 2
srvctl predict scan
Predicts the consequences of SCAN failure.
Syntax and Parameters
Use the srvctl predict scan
command with the following syntax: srvctl predict scan -scannumber
ordinal_number
[-verbose]
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Table A-67 srvctl predict scan Parameters
Parameter
-scannumber ordinal_number
Description
An ordinal number that identifies the SCAN VIP for which you want to simulate failure. The range of values you can specify for this parameter is 1 to
3.
Display verbose output.
-verbose
Example
An example of this command is:
$ srvctl predict scan -scannumber 1 -verbose
srvctl predict scan_listener
Predicts the consequences of SCAN listener failure.
Syntax and Parameters
Use the srvctl predict scan_listener
command with the following syntax: srvctl predict scan_listener -scannumber
ordinal_number
[-verbose]
Table A-68 srvctl predict scan_listener Parameters
Parameter
-scannumber ordinal_number
Description
An ordinal number that identifies the SCAN listener. The range of values you can specify for this parameter is 1 to 3.
Display verbose output.
-verbose
Example
An example of this command is:
$ srvctl predict scan_listener -scannumber 1
srvctl predict service
Predicts the consequences of service failure.
Syntax and Parameters
Use the srvctl predict service
command with the following syntax: srvctl predict service -db
db_unique_name
-service
service_name
[-verbose]
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Table A-69 srvctl predict service Parameters
Parameter Description
Unique name for the database
-db db_unique_name
Comma-delimited list of service names
-service "service_name,..."
Display verbose output
-verbose
Example
To evaluate the consequences of failure of the service named crm
for the database racdb
:
$ srvctl predict service -db racdb -service "crm"
srvctl predict vip
Predicts the consequences of VIP failure.
Syntax and Options
Use the srvctl predict vip
command with the following syntax: srvctl predict vip [-vip vip_name] [-verbose]
Table A-70 srvctl predict vip Parameters
Parameter
-vip vip_name
Description
Specify the name of the VIP for which you want to evaluate the consequences of failure.
Display verbose output
-verbose
Example
An example of this command is:
$ srvctl predict vip -vip racdb1_vip
The relocate
command causes the specified object to run on a different node.
The specified object must be running already.
The relocation of the object is temporary until you modify the configuration. The
command permanently changes the configuration.
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Table A-71 srvctl relocate Command Summary
Command
srvctl relocate database srvctl relocate instance srvctl relocate scan srvctl relocate scan_listener srvctl relocate service srvctl relocate vip
Description
Relocates an Oracle RAC One Node database to a different node.
Relocates a database instance.
Relocates a SCAN VIP from its current hosting server to another server within the cluster.
Relocates a SCAN listener from its current hosting server to another server within the cluster.
Relocates the named services from one named instance to another named instance, or all services that can move, if no service is specified. Services that cannot move remain where they are.
Relocates a specific VIP from one node to another node within the cluster.
srvctl relocate database
The srvctl relocate database
command initiates the relocation of an Oracle
RAC One Node database from one node to another node. This command also cleans up after a failed relocation.
The srvctl relocate database
command can only be used for relocating Oracle
RAC One Node databases.
Syntax and Parameters
Use the srvctl relocate database
command with one of these syntax models: srvctl relocate database -db db_unique_name [-node target_node]
[-timeout timeout] [-stopoption NORMAL] [-verbose] srvctl relocate database -db db_unique_name -abort [-revert] [-verbose]
Table A-72 srvctl relocate database Parameters
Parameter Description
Unique name of the database to relocate.
-db db_unique_name
-node target
-timeout timeout
-stopoption NORMAL
Target node to which to relocate the Oracle RAC One Node database.
Note:
You must supply this parameter if you are relocating an administrator-managed Oracle RAC One Node database.
Online database relocation timeout, in minutes, for Oracle
RAC One Node databases. The default is
30
.
Use this parameter to shut down an existing database instance using
SHUTDOWN NORMAL
instead of the default of
SHUTDOWN TRANSACTIONAL LOCAL
for a primary database or
SHUTDOWN IMMEDIATE
for a standby database.
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Table A-72 (Cont.) srvctl relocate database Parameters
Parameter Description
Abort failed online database relocation.
-abort
-revert
Removes the target node of a failed online relocation request from the candidate server list of an administratormanaged Oracle RAC One Node database.
Verbose output.
-verbose
Usage Notes
• If the Oracle RAC One Node database you want to relocate is not running, then the command returns an error.
• If another online database relocation is active for this Oracle RAC One Node database, then the command returns an error.
• If an online database relocation for this Oracle RAC One Node database has failed and the target nodes are not the same for either relocation, then the command returns an error instructing you to abort the failed online database relocation and then initiate a new one.
• If an online database relocation for this Oracle RAC One Node database has failed and the target nodes are the same (or you do not specify the target), then the command attempts to relocate the database.
Example
The following example relocates an administrator-managed Oracle RAC One Node database named rac1
to a server called node7
.
srvctl relocate database -db rac1 -node node7
srvctl relocate scan
Relocates a specific SCAN VIP from its current hosting node to another node within the cluster.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl relocate scan
command with the following syntax: srvctl relocate scan -scannumber
ordinal_number
[-node node_name]
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Table A-73 srvctl relocate scan Parameters
Parameter
-scannumber ordinal_number
-node node_name
Description
An ordinal number that identifies which SCAN
VIP you want to relocate. The range of values you can specify for this parameter is 1 to 3.
The name of a single node.
If you do not specify this parameter, then the utility chooses the node to which the SCAN VIP is relocated.
Example
An example of this command is:
$ srvctl relocate scan -scannumber 1 -node node1
srvctl relocate scan_listener
Relocates a specific SCAN listener from its current hosting node to another node within the cluster.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl relocate scan_listener
command with the following syntax: srvctl relocate scan_listener -scannumber
ordinal_number
[-node node_name]
Table A-74 srvctl relocate scan_listener Parameters
Parameter
-scannumber ordinal_number
-node node_name
Description
An ordinal number that identifies which SCAN VIP you want to relocate. The range of values you can specify for this parameter is 1 to 3.
The name of a single node.
If you do not specify this parameter, then the utility chooses the node to which the SCAN VIP is relocated.
Example
An example of this command is:
$ srvctl relocate scan_listener -scannumber 3
srvctl relocate server
Relocates servers to a server pool in the cluster.
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Syntax and Parameters
Use the srvctl relocate server
command with the following syntax: srvctl relocate server -servers "
server_name_list
" -serverpool pool_name
[-eval] [-force]
Table A-75 srvctl relocate server Parameters
Parameter
-servers "server_name_list"
-serverpool pool_name
Description
A single server name or a comma-delimited list of server names enclosed in double quotation marks (
""
) that you want to relocate to a different server pool.
The name of the server pool to which you want to move servers.
-eval
-force
Use this parameter to hypothetically evaluate the impact of the command on the system.
Use the
-force
parameter to force the relocation of servers even if it means stopping some resources.
Example
An example of this command is:
$ srvctl relocate server -servers "server1, server2" -serverpool sp3
srvctl relocate service
Use the srvctl relocate service
command to temporarily relocate the specified service names from one specified instance to another specified instance.
This command works on only one source instance and one target instance at a time, relocating a service or all services from a single source instance to a single target instance.
Syntax
srvctl relocate service -db db_unique_name [-service service_name
| -pdb pluggable_database] {-oldinst old_inst_name
[-newinst new_inst_name] | -currentnode source_node [-targetnode target_node]} [drain_timeout timeout]
[-wait YES | NO] [-pq] [-force [-noreplay]] [-eval] [-verbose]
Parameters
Table A-76 srvctl relocate service Command Parameters
Parameter Description
-db db_unique_name
Specify a unique name for the database.
-service
service_name
Specify the name of the service you want to relocate. If you do not specify any services, then all services that can be relocated, are relocated. Those that cannot be relocated remain in place.
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Table A-76 (Cont.) srvctl relocate service Command Parameters
Parameter
-pdb
pluggable_database
Description
Use this parameter to relocate services running on a specific pluggable database.
-oldinst
old_inst_name
-newinst
new_inst_name
-currentnode
source_node
Specify the name of the instance from which you are relocating the service.
Specify the name of the instance to which you are relocating the service. This parameter is optional. If you do not specify an instance, then Oracle Clusterware chooses a new one.
Note:
If you are using an administrator-managed database, then you must use the
-oldinst
and
-newinst
parameters and the target instance must be on the preferred or available list for the service.
Name of the node where the service is currently running.
-targetnode
target_node
-drain_timeout
timeout
-wait YES | NO
Name of node where the service is to be relocated. If you do not specify a target node, then Oracle Clusterware chooses a new location.
Note:
If you are using a policy-managed database, then you must use the
-currentnode
and
-targetnode
parameters.
Specify the time, in seconds, allowed for resource draining to be completed. Accepted values are an empty string (""), 0, or any positive integer. The default value is an empty string, which means that this parameter is not set. If it is set to 0, then draining occurs, immediately.
The draining period is intended for planned maintenance operations. During the draining period, all current client requests are processed, but new requests are not accepted. When set on the service this value is used when the command line value is not set.
Choose
YES
to wait until service draining is completed on the node from which you are relocating the service.
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Table A-76 (Cont.) srvctl relocate service Command Parameters
Parameter Description
-stopoption option
Specify the mode in which the service is stopped. When set on the service, this value is used if you do not set the value on the command line.
IMMEDIATE
permits sessions to drain before the service is stopped.
TRANSACTIONAL
permits sessions to drain for the amount of time specified in the
-drain_timeout
parameter. The service is stopped when the time limit is reached and any remaining sessions are terminated.
If you specify
NONE
, then no sessions are terminated.
The default is taken from the service setting, when specified on the service. Otherwise the default is
NONE
.
Note:
You must use the
-stopoption
parameter with the
force
parameter.
–pq
Performs the action on a parallel query service.
–force [-noreplay]
Disconnect all sessions during stop or relocate service operations.
Optionally, you can specify the
-noreplay
parameter if you do not want Application Continuity to replay in-flight transactions after a session is terminated during stop or relocate service operations.
The
-noreplay
parameter is not limited to use with
-force
but
-force
does require
-noreplay
if you do not want to replay inflight transactions after you force the service to disconnect all sessions.
–eval
–verbose
Use this parameter to hypothetically evaluate the impact of the command on the system.
Verbose output.
Example
To temporarily relocate a named service member for the crm
service from the database instance crm1
to the database instance crm3
:
$ srvctl relocate service -db crm -service crm -oldinst crm1 -newinst crm3
Related Topics:
SQL*Plus User's Guide and Reference
srvctl relocate vip
Relocates a specific VIP from its current hosting node to another node within the cluster.
Syntax and Options
Use the srvctl relocate vip
command with the following syntax:
Server Control Utility Reference A-97
SRVCTL Command Reference srvctl relocate vip -vip vip_name [-node node_name] [-force] [-verbose]
Table A-77 srvctl relocate vip Parameters
Parameter Description
Specify the name of the VIP you want to relocate.
-vip vip_name
-node node_name
Specify the name of the target node where the VIP should be relocated.
Specify this option to force the relocation of the VIP.
-force
-verbose
Display verbose output.
Example
An example of this command is:
$ srvctl relocate vip -vip vip1 -node node3
remove
Removes the configuration information for the specified target from Oracle
Clusterware. Environment settings for the object are also removed.
Using this command does not destroy the specified target.
Use the remove
verb to remove the associated resource from the management of
Oracle Clusterware or Oracle Restart. Depending on the noun used, you can remove databases, services, nodeapps, Oracle Notification Service, and listeners.
If you do not use the force parameter (
-force
), then Oracle Clusterware or Oracle
Restart prompts you to confirm whether to proceed. If you use
-force
, then the remove operation proceeds without prompting and continues processing even when it encounters errors. Even when the Oracle Clusterware resources cannot be removed, the OCR configuration is removed, so that the object now appears not to exist, but there are still Oracle Clusterware resources. Use the force parameter (
-force
) with extreme caution because this could result in an inconsistent OCR.
To use the remove
verb, you must first stop the node applications, database, instance, or service for which you are specifying srvctl remove
. Oracle recommends that you perform a disable operation before using this command, but this is not required.
You must stop the target object before running the srvctl remove
command. See the
command.
Table A-78 srvctl remove Summary
Command
Description
Removes a database and configuration
Removes a disk group from the Oracle Clusterware or Oracle
Restart configuration
Removes instances and configurations of administrator-managed databases
A-98 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference
Table A-78 (Cont.) srvctl remove Summary
Command
srvctl remove network srvctl remove nodeapps
Removes node applications
Removes Oracle Notification Service instances
Removes all Oracle Clusterware resources for all SCAN VIPs
Removes all Oracle Clusterware resources for all SCAN listeners
Description
Removes the configuration of the specified listener from Oracle
Clusterware or Oracle Restart
Removes a network from the cluster configuration
Removes services from the Oracle Clusterware or Oracle Restart configuration
Removes a specific server pool
Removes specific VIPs
Removes a specific volume
srvctl remove database
Removes database configurations.
After running this command, ensure that the password file is in the default location if you want to connect to the database as the SYS user with the SYS user's password.
Syntax
srvctl remove database -db db_unique_name [-force] [-noprompt] [-verbose]
Parameters
Table A-79 srvctl remove database Command Parameters
Parameter
-database
db_unique_name
-force
Description
Unique name for the database.
-noprompt
-verbose
Forcibly remove the database and ignore any dependencies.
Suppress prompts.
Display verbose output.
Example
To remove a database named crm
:
$ srvctl remove database -db crm
Server Control Utility Reference A-99
SRVCTL Command Reference
srvctl remove diskgroup
Removes a specific Oracle ASM disk group resource from Oracle Clusterware or
Oracle Restart.
Syntax and Parameters
Use the srvctl remove diskgroup
command with the following syntax: srvctl remove diskgroup -diskgroup
diskgroup_name
[-force]
Table A-80 srvctl remove diskgroup Parameters
Parameter Description
The Oracle ASM disk group name.
-diskgroup diskgroup_name
Force remove (ignore dependencies)
-force
Example
An example of this command is:
$ srvctl remove diskgroup -diskgroup DG1 -force
srvctl remove instance
Removes the configurations for an instance of an administrator-managed database. To remove the configurations of a policy-managed database, you must shrink the size of the server pool with the
srvctl modify srvpool command.
If you use the
-force
parameter, then any services running on the instance stop.
Oracle recommends that you reconfigure services to not use the instance to be removed as a preferred or available instance before removing the instance.
Note:
• This command is only available with Oracle Clusterware and Oracle
RAC.
• If you attempt to use this command on an Oracle RAC One Node database, then the command returns an error stating that cannot remove the instance except by removing the database.
Syntax and Parameters
Use the srvctl remove instance
command with the following syntax: srvctl remove instance -db
db_unique_name
-instance instance_name
[-noprompt] [-force]
A-100 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference
Table A-81 srvctl remove instance Parameters
Parameter Description
Unique name for the administrator-managed database.
-db db_unique_name
-instance instance_name
Instance name.
Suppress prompts
-noprompt
-force
Specify this parameter to skip checking that the instance is not running, and remove it even though it is running. This parameter also skips checking that the instance has no running services using it, and causes those services to stop before the instance is removed.
Example
An example of this command is:
$ srvctl remove instance -db crm -instance crm01
srvctl remove listener
Removes the configuration of a specific listener or all listeners from Oracle
Clusterware or Oracle Restart.
Syntax and Parameters
Use the srvctl remove listener
command with the following syntax: srvctl remove listener [-listener listener_name | -all] [-force]
Table A-82 srvctl remove listener Parameters
Parameter
-listener listener_name
Description
Name of the listener that you want to remove.
If you do not specify a listener name, then the listener name defaults to
LISTENER
for a database listener;
LISTENER_ASM
for an Oracle ASM listener; or
LISTENER_LEAF
for a Leaf Node listener.
Removes all listener configurations.
-all
-force
Specify this parameter to skip checking whether there are other resources that depend on this listener, such as databases, and remove the listener anyway.
Examples
The following command removes the configuration for the listener named lsnr01
:
$ srvctl remove listener -listener lsnr01
Server Control Utility Reference A-101
SRVCTL Command Reference
srvctl remove network
Removes the network configuration. You must have full administrative privileges to run this command. On Linux and UNIX systems, you must be logged in as root
and on Windows systems, you must be logged in as a user with Administrator privileges.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl remove network
command as follows: srvctl remove network {-netnum network_number | -all} [-force] [-verbose]
Table A-83 srvctl remove network Parameters
Parameter Description
Specifies which network to remove
-netnum network_number
Remove all networks
-all
Force remove the networks
-force
Verbose output
-verbose
Example
An example of this command is:
# srvctl remove network -netnum 3
srvctl remove nodeapps
Removes the node application configuration.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl remove nodeapps
command as follows: srvctl remove nodeapps [-force] [-noprompt] [-verbose]
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SRVCTL Command Reference
Table A-84 srvctl remove nodeapps Parameters
Parameter Description
Force remove
-force
Suppress prompts
-noprompt
Verbose output
-verbose
Usage Notes
You must have full administrative privileges to run this command. On Linux and
UNIX systems, you must be logged in as root
and on Windows systems, you must be logged in as a user with Administrator privileges.
Example
An example of this command is:
# srvctl remove nodeapps
srvctl remove ons
Removes Oracle Notification Service from the Oracle Grid Infrastructure home.
Note:
This command is only available with Oracle Restart.
Syntax and Parameters
Use the srvctl remove ons
command with the following syntax: srvctl remove ons [-force] [-verbose]
Table A-85 srvctl remove ons Parameters
Parameter Description
Force remove
-force
Verbose output
-verbose
srvctl remove scan
Removes Oracle Clusterware resources from all SCAN VIPs.
Syntax
srvctl remove scan [-netnum network_number] [-force] [-noprompt]
Server Control Utility Reference A-103
SRVCTL Command Reference
Parameters
Table A-86 srvctl remove scan Command Parameters
Parameter
-netnum
network_number
–force
–noprompt
Description
The optional network number from which VIPs are obtained. If not specified, the VIPs are obtained from the same default network from which the nodeapps
VIP is obtained.
Removes the SCAN VIPs even though there are SCAN listeners running that are dependent on the SCAN VIPs.
Use this parameter to suppress all prompts.
Usage Notes
If you use the
-force
option, then SCAN VIPs that are running are not stopped before the dependent resources are removed, which may require manual cleanup.
Examples
An example of this command is:
$ srvctl remove scan -force
srvctl remove scan_listener
Removes Oracle Clusterware resources from all SCAN listeners.
Syntax
srvctl remove scan_listener [-netnum network_number] [-force] [-noprompt]
Parameters
Table A-87 srvctl remove scan_listener Command Parameters
Parameter
-netnum
network_number
-force
–noprompt
Description
The optional network number from which SCAN VIPs are obtained. If you do not specify this parameter, then the SCAN
VIPs are obtained from the same default network from which the nodeapps
VIP is obtained.
Removes the SCAN listener without stopping the SCAN listener if it is running.
Use this parameter to suppress all prompts.
Examples
An example of this command is:
$ srvctl remove scan_listener -force
A-104 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference
srvctl remove service
Removes the configuration for a service.
Syntax and Parameters
Use the srvctl remove service
command as follows: srvctl remove service -db
db_unique_name
-service
service_name
[-instance instance_name] [-global_override]
Table A-88 srvctl remove service Parameters
Parameter Description
Unique name for the database
-db db_unique_name
Service name
-service service_name
-instance instance_name
-global_override
Instance name of an administrator-managed database.
Note:
This parameter can be used only for Oracle
Clusterware.
Override value to operate on a global service. This parameter is ignored for a non-global service.
Examples
This command removes the sales
service from all instances of the clustered database named crm
:
$ srvctl remove service -db crm -service sales
The following example removes the sales
service from a specific instance of the crm clustered database:
$ srvctl remove service -db crm -service sales -instance crm02
srvctl remove srvpool
Removes a specific server pool. If there are databases or services that depend upon this server pool, then those resources are removed from the server pool first so that the remove server pool operation succeeds.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl remove srvpool
command with the following syntax: srvctl remove srvpool -serverpool pool_name [-eval] [-verbose]
Server Control Utility Reference A-105
SRVCTL Command Reference
Table A-89 srvctl remove srvpool Parameters
Parameter
-eval
Description
Evaluates the effects of removing a server pool without making any changes to the system.
Display verbose output.
-verbose
Usage Notes
If you successfully remove the specified server pool, then the CRS daemon may assign its servers to other server pools depending upon their minimum size, maximum size, and importance. The CRS daemon may also return these servers to its Free server pool.
Example
An example of this command is:
$ srvctl remove srvpool -serverpool srvpool1
srvctl remove vip
Removes specific VIPs.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl remove vip
command with the following syntax: srvctl remove vip -vip "vip_name_list" [-force] [-noprompt] [-verbose]
Table A-90 srvctl remove vip Parameters
Parameter
-vip "vip_name_list"
Description
A comma-delimited list of VIP names surrounded by double quotation marks (
""
)
Force remove
-force
Suppress prompts
-noprompt
Verbose output
-verbose
Example
An example of this command is:
$ srvctl remove vip -vip "vip1,vip2,vip3" -force -noprompt -verbose
A-106 Oracle Real Application Clusters Administration and Deployment Guide
setenv
SRVCTL Command Reference
srvctl remove volume
Removes a specific volume.
Note:
• This command is only available with Oracle Clusterware.
• The volume gets created when you create volumes in Oracle ASM.
See Also:
Oracle Automatic Storage Management Administrator's Guide
for more information about creating volumes
Syntax and Parameters
Use the srvctl remove volume
command with one of these syntax models: srvctl remove volume -volume
volume_name
-diskgroup
disk_group_name
[-force] srvctl remove volume -device
volume_device
[-force]
Table A-91 srvctl remove volume Parameters
Parameter
-volume volume_name
Description
Specify the name of the volume that you want to remove.
This parameter is required.
-diskgroup disk_group_name
-device volume_device
Specify the name of the disk group in which the volume that you want to remove resides.
Specify the path to the file system resource in which the volume that you want to remove resides.
Removes the volume even if it is running.
-force
Usage Notes
You must specify a particular volume that you want to remove. You can specify a volume that resides in either a particular disk group or on a particular volume device.
Example
The following example removes a volume named
VOLUME1
that resides in a disk group named
DATA
:
$ srvctl remove volume -volume VOLUME1 -diskgroup DATA
The setenv
command sets values for the environment in the configuration file.
Server Control Utility Reference A-107
SRVCTL Command Reference
Use setenv
to set environment variables—items such as language or
TNS_ADMIN
— for Oracle Clusterware that you would typically set in your profile or session when you manage this database or database instance.
The unsetenv
command unsets values for the environment in the configuration file.
Table A-92 srvctl setenv Summary
Command
srvctl setenv database srvctl setenv listener
Description
Administers cluster database environment configurations
Administers listener environment configurations
Note:
You cannot use this command to administer SCAN listeners.
Administers node application environment configurations
Administers VIP environment configurations
srvctl setenv database
Administers cluster database environment configurations.
Syntax and Parameters
Use the srvctl setenv database
command with one of these syntax models: srvctl setenv database -db
db_unique_name
-envs "
name
=
val
[,
name
=
val
][...]" srvctl setenv database -db
db_unique_name
-env "
name
=
val
"
Table A-93 srvctl setenv database Parameters
Parameter Description
Unique name for the database
-db db_unique_name
-envs "name=val,..."
-env "name=val"
Comma-delimited list of name-value pairs of environment variables
Enables single environment variable to be set to a value that contains commas or other special characters
Example
The following example sets the language environment configuration for a cluster database:
$ srvctl setenv database -db crm -env LANG=en
srvctl setenv listener
Administers listener environment configurations.
Syntax and Parameters
Use the srvctl setenv listener
with one of these syntax models:
A-108 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference srvctl setenv listener [-listener
listener_name
] -envs "
name
=
val
[,
name
=
val
][...]" srvctl setenv listener [-listener
listener_name
] -env "
name
=
val
"
Table A-94 srvctl setenv listener Parameters
Parameter
-listener listener_name
-envs "name=val"
Description
Name of the listener.
If you do not specify this parameter, then the listener name defaults to
LISTENER
.
Comma-delimited list of name-value pairs of environment variables.
-env "name=val"
Enables single environment variable to be set to a value that contains commas or other special characters.
Example
The following example sets the language environment configuration for the default listener:
$ srvctl setenv listener -env "LANG=en"
srvctl setenv nodeapps
Sets the environment variables for the node application configurations.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl setenv nodeapps
command with the following syntax model: srvctl setenv nodeapps {-namevals "
name
=
val
[,
name
=
val
][...]" |
-nameval "
name
=
val
"} [-viponly] [-gsdonly] [-onsonly] [-verbose]
Table A-95 srvctl setenv nodeapps Parameters
Parameter
-envs "name=val[,name=val]
[...]"
Description
Comma-delimited list of name-value pairs of environment variables
-env "name=val"
-viponly
-gsdonly
-onsonly
Enables single environment variable to be set to a value that contains commas or other special characters
Modify only the VIP configuration
Modify only the GSD configuration
Modify only the ONS daemon configuration
Server Control Utility Reference A-109
SRVCTL Command Reference
Table A-95 (Cont.) srvctl setenv nodeapps Parameters
Parameter Description
Verbose output
-verbose
Example
To set an environment variable for all node applications:
$ srvctl setenv nodeapps -env "CLASSPATH=/usr/local/jdk/jre/rt.jar" -verbose
srvctl setenv vip
Administers cluster VIP environment configurations.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl setenv vip
command with the following syntax: srvctl setenv vip -vip
vip_name
{-envs
"name
=
val
[,
name
=
val
,...]" |
-env "
name
=
val"
} [-verbose]
Table A-96 srvctl setenv vip Parameters
Parameter Description
Name of the VIP
-vip vip_name
-envs "name=val,..."
-env "name=val"
Comma-delimited list of name-value pairs of environment variables
Enables single environment variable to be set to a value that contains commas or other special characters
Verbose output
-verbose
Example
The following example sets the language environment configuration for a cluster VIP:
$ srvctl setenv vip -vip crm1-vip -env "LANG=en"
start
A summary list of srvctl start
commands and their descriptions.
Starts Oracle Restart or Oracle Clusterware enabled, non-running applications for the database, all or named instances, all or named service names, or node-level applications. For the start
command, and for other operations that use a connect
A-110 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference string, if you do not provide a connect string, SRVCTL uses
/as sysrac
to perform the operation. To run such operations, the owner of the oracle
binary executables must be a member of the OSRAC group, and users running the commands must also be in the OSRAC group.
Table A-97 srvctl start Summary
Command
srvctl start database srvctl start diskgroup srvctl start home
Description
Starts the cluster database and its instances
Starts a specified disk group on a number of nodes
Starts Oracle Clusterware-managed or Oracle Restart-managed resources in a specific Oracle home
Starts the instance srvctl start instance srvctl start listener srvctl start nodeapps srvctl start ons srvctl start scan srvctl start scan_listener srvctl start service srvctl start vip srvctl start volume
Starts the specified listener or listeners
Starts the node applications
Starts the Oracle Notification Service daemon for Oracle Restart
Starts all SCAN VIPs
Starts all SCAN listeners
Starts a service
Starts a VIP
Starts an enabled volume
srvctl start database
Starts a cluster database and its enabled instances and all listeners on nodes with database instances. You can disable listeners that should not be started.
Syntax and Parameters
Use the srvctl start database
command with the following syntax: srvctl start database -db
db_unique_name
[-eval]
[-startoption
start_options
] [-stopconcurrency number_of_instances] [-node
node_name]
Table A-98 srvctl start database Parameters
Parameter Description
Unique name for the database
-db db_unique_name
Server Control Utility Reference A-111
SRVCTL Command Reference
Table A-98 (Cont.) srvctl start database Parameters
Parameter
-eval
Description
Use this parameter to hypothetically evaluate the impact of the command on the system.
-startoption
start_options
[-startconcurrency
number_of_instances]
Options for startup command (for example:
OPEN
,
MOUNT
, or
NOMOUNT
)
Notes:
• This command parameter supports all database startup options.
• For multi-word startup options, such as read only
and read write
, separate the words with a space and enclose in double quotation marks (
""
). For example,
"read only"
.
See Also:
SQL*Plus User's Guide and Reference for more information about startup options
Specify a number of database instances to start simultaneously, or specify
0
for an empty start concurrency value.
-node node_name
The name of the node on which you want to start the database
Notes:
• This command only applies to Oracle RAC One Node databases.
• The node you specify must be in the candidate list for an administrator-managed Oracle RAC One Node database or in the server pool for a policy-managed Oracle RAC
One Node database.
• If the database is already running on a node than the one you specify, then the command returns an error.
• If you do not specify a node, then Oracle Clusterware chooses which node on which to start the Oracle RAC One
Node database according to its policies, such as dispersion, number of resources, and order of candidate nodes.
• If there is an active online database relocation for the
Oracle RAC One Node database you are attempting to start, then both instances will already be running and the command returns an error message saying so (remember that only during an online database relocation are two instances of an Oracle RAC One Node database in existence).
If the online database relocation failed for the Oracle RAC
One Node database and you do not specify a node, then the command attempts to start both database instances.
If the online database relocation failed for the Oracle RAC
One Node database and you specify a node, then the command attempts to abort the failed relocation and start the instance on that node.
Example
An example of this command is:
$ srvctl start database -db crm -startoption "read only"
A-112 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference
srvctl start diskgroup
Start a a specific disk group resource on a number of specified nodes.
Syntax and Parameters
Use the srvctl start diskgroup
command with the following syntax: srvctl start diskgroup -diskgroup
diskgrp_name
[-node "
node_list
"]
Table A-99 srvctl start diskgroup Parameters
Parameter Description
The Oracle ASM disk group name
-diskgroup diskgrp_name
-node "node_list"
Comma-delimited list of node names on which to start the disk group resource
Note:
This parameter can be used only with Oracle
Clusterware.
Example
An example of this command is:
$ srvctl start diskgroup -diskgroup diskgroup1 -node "mynode1,mynode2"
srvctl start home
Starts all the Oracle Restart-managed or Oracle Clusterware-managed resources on the specified Oracle home.
Syntax and Parameters
Use the srvctl start home
command with the following syntax: srvctl start home -oraclehome Oracle_home -statefile state_file -node node_name
Table A-100 srvctl start home Parameters
Parameter
-oraclehome Oracle_home
Description
The path to the Oracle home for which you want to start the Oracle Restart or Oracle Clusterware-managed resources.
The path name where you want the state file to be written.
-statefile state_file
-node node_name
The name of the node where the Oracle home resides.
Note:
This parameter can be used only with Oracle
Clusterware.
Example
An example of this command is:
$ srvctl start home -oraclehome /u01/app/oracle/product/12.1.0/db_1
-statefile ~/state.txt -node node1
Server Control Utility Reference A-113
SRVCTL Command Reference
srvctl start instance
Starts instances in the cluster database.
Use the srvctl start instance
command to start database instances, and all listeners on nodes with database instances
Syntax
Use the srvctl start instance
command with one of these syntax models: srvctl start instance -db db_unique_name -node node_name
[-instance "instance_name"] [-startoption start_options] srvctl start instance -db db_unique_name -instance "inst_name_list"
[-startoption start_options]
Parameters
Table A-101 srvctl start instance Parameters
Parameter Description
-db db_unique_name
Unique name for the database.
-node node_name
-instance
{ "instance_name"
|
"inst_name_list" }
-startoption
start_options
The name of a single node.
Note:
Use this parameter for policy-managed databases.
The name of a single instance or a comma-delimited list of instance names
Note:
Use this parameter for administrator-managed databases.
Options for startup command, such as
OPEN
,
MOUNT
, or
NOMOUNT
Note:
For multi-word startup options, such as read only
and read write
, separate the words with a space and enclose in double quotation marks (
""
). For example,
"read only"
.
)
Usage Notes
• This command is only available with Oracle Clusterware and Oracle RAC.
• If you run this command on an Oracle RAC One Node database, then the command returns an error instructing you to use the database
noun, instead.
Related Topics:
SQL*Plus User's Guide and Reference
srvctl start listener
Starts the default listener on specific node, or starts the specified listener on all nodes that are registered with Oracle Clusterware or on the given node.
Syntax
srvctl start listener [-node node_name] [-listener listener_name]
A-114 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference
Parameters
Table A-102 srvctl start listener Command Parameters
Parameter
-node node_name
-listener
listener_name
Description
Specify a particular node name to start the listener on that node.
Note:
You can only use this parameter with Oracle Clusterware.
Specify a particular listener name. Use the
command to obtain the name of a listener.
If you do not assign a value to this parameter, then SRVCTL starts all known listeners in the cluster.
Examples
An example of this command is:
$ srvctl start listener -listener LISTENER_LEAF
srvctl start nodeapps
Starts node-level applications on a node or all nodes in the cluster.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl start nodeapps
command with the following syntax: srvctl start nodeapps [-node
node_name
] [-gsdonly] [-adminhelper] [-verbose]
Table A-103 srvctl start nodeapps Parameters
Parameter
-node node_name
Description
Node name
If you do not specify this parameter, then the utility starts the nodeapps on all active nodes in the cluster.
Starts only GSD instead of all node applications
-gsdonly
-adminhelper
Starts only an Administrator helper instead of all node applications
Verbose output
-verbose
Example
An example of this command is:
$ srvctl start nodeapps
Server Control Utility Reference A-115
SRVCTL Command Reference
srvctl start ons
Starts the Oracle Notification Service daemon.
Note:
This command is only available with Oracle Restart.
Syntax and Parameters
Use the srvctl start ons
command with the following syntax: srvctl start ons [-verbose]
There is only one parameter for this command,
-verbose
, which is used to indicate that verbose output should be displayed.
srvctl start scan
Starts all SCAN VIPs, by default, or a specific SCAN VIP, on all nodes or a specific node in the cluster.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl start scan
command with the following syntax: srvctl start scan [-scannumber
ordinal_number
] [-node node_name]
Table A-104 srvctl start scan Parameters
Parameter
-scannumber ordinal_number
-node node_name
Description
An ordinal number that identifies which SCAN VIP you want to start. The range of values you can specify for this parameter is 1 to 3.
If you do not specify this parameter, then the utility starts all the SCAN VIPs.
The name of a single node.
If you do not specify this parameter, then the utility starts the SCAN VIPs on all nodes in the cluster.
Example
To start the SCAN VIP identified by the ordinal number 1 on the crm1
node, use the following command:
$ srvctl start scan -scannumber 1 -node crm1
srvctl start scan_listener
Starts all SCAN listeners, by default, or a specific listener on all nodes or a specific node in the cluster.
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Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl start scan_listener
command with the following syntax: srvctl start scan_listener [-node
node_name
] [-scannumber
ordinal_number
]
Table A-105 srvctl start scan_listener Parameters
Parameter
-scannumber ordinal_number
-node node_name
Description
An ordinal number that identifies which SCAN
Listener you want to start. The range of values you can specify for this parameter is 1 to 3.
If you do not specify this parameter, then the utility starts all the SCAN listeners.
The name of a single node.
If you do not specify this parameter, then the utility starts the SCAN listeners on all nodes in the cluster.
Example
An example of this command is:
$ srvctl start scan_listener -scannumber 1
srvctl start service
Starts a service or multiple services on a database, pluggable database, or instance.
Syntax
srvctl start service [-db db_unique_name] [-service "services_list"
[-pq] | -pdb pluggable_database | -serverpool pool_name]
[-node node_name | -instance instance_name]
[-global_override] [-startoption start_options] [-eval] [-verbose]
Parameters
Parameter Description
-db db_unique_name
Specify a unique name for the database.
-service
"service_list"
-pq
Specify a service name or a comma-delimited list of service names enclosed in double quotation marks ("").
If you do not include this parameter, then SRVCTL starts all of the services for the specified database.
Note:
All manual service startup must specify the name of the service to be started by the user.
Specify this parameter to restrict the start action to a parallel query service.
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Parameter
-pdb
pluggable_database
Description
Specify the name of a pluggable database. Optionally, you can specify either the name of a node or the name of an instance to restrict the starting of services to that particular object on the pluggable database.
-serverpool
pool_name
-node node_name
Alternative to using the
-pq
parameter, you can specify the name of a server pool that contains the services you want to start. Use this parameter for policy-managed databases.
Specify the name of a node where the services reside that you want to start. Use this parameter for policy-managed databases.
-instance
instance_name
-global_override
-startoption
start_options
–verbose
Specify the name of an instance where the services reside that you want to start. Use this parameter for administrator-managed databases.
Override value to operate on a global service. Use this parameter only with global services; this parameter is ignored if specified for a non-global service.
Specify startup options used when service startup requires starting a database instance. Options include
OPEN
,
MOUNT
, and
NOMOUNT
.
Note:
For multi-word startup options, such as read only
and read write
, separate the words with a space and enclose in double quotation marks (
""
). For example,
"read only"
.
Display verbose output.
Usage Notes
• The srvctl start service
command will fail if you attempt to start a service that is already running.
• The srvctl start service
command will fail if you attempt to start a service on an instance, if that service is already running on its maximum number of instances, that is, its number of preferred instances.
• You can move a service or change the status of a service on an instance with the srvctl modify service
and srvctl relocate service
commands.
Examples
The following example starts all services on a specific database:
$ srvctl start database -db myDB
The following examples start a list of services (optionally restricted to a parallel query services in the latter example) regardless of the pluggable database on which they may reside:
$ srvctl start database -db myDB -service "myServ01,myServ02"
$ srvctl start database -db myDB -service "myServ01,myServ02" -pq
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The following example starts all services in a given server pool:
$ srvctl start database -db myDB -serverpool myServerPool
The following examples start all services on a given pluggable database, optionally restricted to a single node or a single instance in the latter two examples, repectively:
$ srvctl start service -db myDB -pdb myPDB1
$ srvctl start service -db myDB -pdb myPDB1 -node myRACNode01
$ srvctl start service -db myDB -pdb myPDB1 -instance myDB01
The following example starts all services, for a given database, on a given instance (for all pluggable databases):
$ srvctl start service -db myDB -instance myDB01
The following example start all services for a given database on a given node (for all pluggable databases):
$ srvctl start service -db myDB -node myRACNode01
The following examples start a list of services on a given node or given instance:
$ srvctl start service -db myDB -service "myService01,myService02" -node myRACNode01
$ srvctl start service -db myDB -service "myService01,myService02" -instance myDB01
srvctl start vip
Starts a specific VIP or a VIP on a specific node.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl start vip
command with the following syntax: srvctl start vip {-node node_name | -vip vip_name } [-verbose]
Table A-106 srvctl start vip Parameters
Parameter Description
Node name
-node node_name
The VIP name
-vip vip_name
Verbose start
-verbose
Example
An example of this command is:
$ srvctl start vip -vip crm1-vip -verbose
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srvctl start volume
Starts a specific, enabled volume.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl start volume
command with the following syntax: srvctl start volume {-volume
volume_name
-diskgroup
disk_group_name
|
-device
volume_device
} [-node node_list]
Table A-107 srvctl start volume Parameters
Parameter
-volume volume_name
Description
Specify the name of the volume that you want to start. This parameter is required.
-diskgroup
disk_group_name
Specify the name of the disk group in which the volume that you want to start resides.
Specify the path to the volume device that you want to start.
-device volume_device
-node node_list
Specify a comma-delimited list of node names where volumes that you want to start reside.
Usage Notes
The srvctl start volume
command does not create a volume service. Provided that the volume already exists and the volume resource is enabled, SRVCTL attempts to start it. If the volume exists but the resource is disabled, then srvctl start volume
returns an error.
Example
The following example starts a volume named
VOLUME1
that resides in a disk group named
DATA
:
$ srvctl start volume -volume VOLUME1 -diskgroup DATA
status
Displays the current state of a named database, instances, services, disk group, listener, node application, or other resource managed by Oracle Clusterware.
If you use the
-verbose
parameter with the status command, then SRVCTL displays the
INTERNAL_STATE
, which indicates actions in progress by Oracle Clusterware, such as starting, stopping, or cleaning. If the internal state is STABLE, then the
verbose
parameter displays nothing because this is the normal state. Additionally, the
-verbose
parameter displays
STATE_DETAILS
, which may indicate additional information provided by the resource about why it is in its current state
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Table A-108 srvctl status Summary
Command
srvctl status instance srvctl status listener
srvctl status nodeapps srvctl status ons srvctl status scan
srvctl status server srvctl status service
srvctl status srvpool srvctl status vip
Description
Displays the status of a database
Displays the status of a specific disk group on a number of nodes
Displays the status of the resources associated with the specified
Oracle home
Displays the status of a instance
Displays the status of a listener resource
Displays the status of node applications
Displays the status of Oracle Notification Service
Displays the status of SCAN VIPs
Displays the status of SCAN listeners
Displays the status of servers
Displays the status of services
Displays the status of server pools
Displays the status of VIPs
Displays the status of volumes
srvctl status database
This command displays the current state of the of the database.
Syntax
srvctl status database {-db db_unique_name {[-serverpool serverpool_name]
| [-sid] [-home]} | -serverpool serverpool_name | -thisversion | -thishome}
[-force] [-detail] [-verbose]
Parameters
Table A-109 srvctl status database Parameters
Parameter Description
-db db_unique_name
Specify a unique name for the database.
-serverpool
serverpool_name
–sid
Optionally, you can specify a server pool that SRVCTL will display information on nodes contained within.
Use this parameter to display the SID of the Oracle instance running on this node.
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Table A-109 (Cont.) srvctl status database Parameters
Parameter
–home
-thisversion
-thishome
-force
–detail
-verbose
Description
Use this parameter to display the Oracle home of the specified database.
Use this parameter to display the status of databases that are of the same Oracle product version as SRVCTL.
Use this parameter to display the status of databases that are configured in this Oracle home.
Include disabled applications
Use this parameter to display detailed database status information.
Displays
STATE_DETAILS
and
INTERNAL_STATE
attributes, which include
STABLE
,
STARTING
,
STOPPING
, and
CLEANING
.
If the
INTERNAL_STATE
is
STABLE
, then SRVCTL displays no additional information. If the
INTERNAL_STATE
is
STARTING
, then SRVCTL displays:
Instance {0} is being started
If the
INTERNAL_STATE
is
CLEANING
, then SRVCTL displays:
Instance {0} is being cleaned up
Usage Notes
The output of this command includes information on the Oracle ASM or Oracle ASM
IOServer instance for each running instance of the database.
Examples
This command displays output similar to the following:
$ srvctl status database -db db00 -detail
Instance {0} is connected to ASM instance {1}
Instance {0} is connected to ASM I/O server instance {1}
srvctl status diskgroup
Displays the status of a specific disk group on a number of specified nodes.
Syntax and Parameters
Use the srvctl status diskgroup
command with the following syntax: srvctl status diskgroup -diskgroup
diskgroup_name
[-node "
node_list
"]
[-detail] [-verbose]
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Table A-110 srvctl status diskgroup Parameters
Parameter Description
The Oracle ASM disk group name
-diskgroup diskgroup_name
-node node_list
Comma-delimited list of node names on which to check status of the disk group
Note:
This parameter can be used only with Oracle
Clusterware.
Display detailed status information for the disk group
-detail
Displays verbose output.
-verbose
Example
An example of this command is:
$ srvctl status diskgroup -diskgroup dgrp1 -node "mynode1,mynode2" -detail
srvctl status home
Displays the status of all the Oracle Restart-managed or Oracle Clusterware-managed resources for the specified Oracle home.
Syntax and Parameters
Use the srvctl status home
command with the following syntax: srvctl status home -oraclehome
Oracle_home
-statefile state_file -node
node_name
Table A-111 srvctl status home Parameters
Parameter
-oraclehome Oracle_home
-statefile state_file
Description
The path to the Oracle home for which you want to start the Oracle Restart or Oracle Clusterware-managed resources
The path name for the text file that holds the state information generated by this command.
-node node_name
The name of the node where the Oracle home resides.
Note:
This parameter is required and can be used only with Oracle Clusterware.
Example
An example of this command is:
$ srvctl status home -oraclehome /u01/app/oracle/product/12.1/dbhome_1 -statefile
~/state.txt -node stvm12
The preceding command returns output similar to the following:
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Database cdb1 is running on node stvm12
srvctl status instance
The srvctly status instance
command displays the status of Oracle database instances.
The output of this command includes information about the Oracle ASM or Oracle
ASM IOServer instance for each running instance of the database.
Syntax
srvctl status instance -db db_unique_name {-node node_name
| -instance "instance_name_list"} [-detail] [-force] [-verbose]
Parameters
Table A-112 srvctl status instance Parameters
Parameter Description
-db db_unique_name
Unique name for the database.
-node node_name
-instance
"inst_name_list"
Node name.
Note:
Use this parameter for policy-managed databases.
Comma-delimited list of instance names.
Note:
Use this parameter for administrator-managed databases.
-detail
-force
-verbose
Use this parameter to display detailed status information.
Include disabled applications
Displays verbose output
Example
This command displays output similar to the following:
$ srvctl status instance -db db00 -node node10 -verbose
Instance db0010 running on node node10 is connected to ASM I/O Server instance +IOS1
srvctl status listener
Displays the status of listener resources.
Syntax and Parameters
Use the srvctl status listener
command with the following syntax: srvctl status listener [-listener
listener_name
] [-node
node_name
] [-verbose]
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Table A-113 srvctl status listener Parameters
Parameter
-listener listener_name
-node node_name
Description
Name of a listener.
If you do not specify this parameter, then the listener name defaults to
LISTENER
Name of a cluster node.
Note:
This parameter can be used only for Oracle Clusterware.
Displays verbose output.
-verbose
Example
To display the status of the default listener on the node node2
, use the following command:
$ srvctl status listener -node node2
srvctl status nodeapps
Displays the status of node applications.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl status nodeapps
command with the following syntax: srvctl status nodeapps [-node node_name]
You can optionally specify the node for which to display the status of the node applications.
srvctl status ons
Displays the current state of the Oracle Notification Service daemon.
Note:
This command is only available with Oracle Restart.
Syntax and Parameters
Use the srvctl status ons
command with the following syntax: srvctl status ons
srvctl status scan
Displays the status for all SCAN VIPs, by default, or a specific SCAN VIP.
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Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl status scan
command with the following syntax: srvctl status scan [-scannumber
ordinal_number
] [-verbose]
Table A-114 srvctl status scan Parameters
Parameter
-scannumber ordinal_number
Description
Specify an ordinal number that identifies a specific SCAN
VIP. The range of values you can specify for this parameter is 1 to 3. If you do not specify this parameter, then the utility displays the status of all SCAN VIPs in the cluster.
Displays verbose output.
-verbose
Example
An example of this command is:
$ srvctl status scan -scannumber 1
srvctl status scan_listener
Displays the status for all SCAN listeners, by default, or a specific listener.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl status scan_listener
command with the following syntax: srvctl status scan_listener [-scannumber
ordinal_number
] [-verbose]
Table A-115 srvctl status scan_listener Parameters
Parameter
-scannumber ordinal_number
Description
Specify an ordinal number that identifies a specific SCAN
VIP. The range of values you can specify for this parameter is 1 to 3. If you do not specify this parameter, then the utility displays the status of all SCAN VIPs in the cluster.
Displays verbose output.
-verbose
Example
An example of this command is:
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$ srvctl status scan_listener -scannumber 1
srvctl status server
Displays the current state of named servers.
Syntax and Parameters
Use the srvctl status server
command with the following syntax: srvctl status server -server "
server_name_list
" [-detail]
Table A-116 srvctl status server Parameters
Parameter Description
Comma-delimited list of server names.
-server "server_name_list"
Print detailed status information.
-detail
Example
The following example displays the status of a named server:
$ srvctl status server -server "server11" -detail
srvctl status service
Displays the status of a service.
For Oracle RAC One Node databases, if there is an online database relocation in process, then the srvctl status service
command displays the source and destination nodes and the status of the relocation, whether it is active or failed.
Syntax and Parameters
Use the srvctl status service
command with the following syntax: srvctl status service -db
db_unique_name
[-service "
service_name_list
"]
[-force] [-verbose]
Table A-117 srvctl status service Parameters
Parameter Description
Unique name for the database
-db db_unique_name
-services "service_name_list"
Comma-delimited list of service names.
If you do not specify this parameter, then the utility lists the status of all services for the specified database.
Include disabled applications
-force
Displays verbose output.
-verbose
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Example
The following example displays the status of a named service across the clustered database:
$ srvctl status service -db crm -service "crm" -verbose
srvctl status srvpool
Displays server pool names, number of servers in server pools, and, optionally, the names of the servers in the server pools.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl status srvpool
command with the following syntax: srvctl status srvpool [-serverpool pool_name] [-detail]
Table A-118 srvctl status srvpool Parameters
Parameter Description
Name of the server pool
-serverpool pool_name
Print detailed status information
-detail
Usage Notes
• If you include the
-detail
parameter but do not specify a specific server pool with the
-serverpool
parameter, then the output of this command includes the names of servers that are currently assigned to each server pool.
• If you use the
-serverpool
parameter to specify a server pool, then the output for this command includes the server pool name and number of servers in the server pool (and, optionally, the server names) for the specified server pool.
Example
An example of this command is:
$ srvctl status srvpool -serverpool srvpool1 -detail
srvctl status vip
Displays status for a specific VIP or a VIP on a specific node.
Note:
This command is only available with Oracle Clusterware.
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Syntax and Parameters
Use the srvctl status vip
command with the following syntax: srvctl status vip {-node node_name | -vip vip_name} [-verbose]
Table A-119 srvctl status vip Parameters
Parameter Description
Node name
-node node_name
The VIP name
-vip vip_name
Displays verbose output.
-verbose
Example
An example of this command is:
$ srvctl status vip -vip node1-vip
srvctl status volume
Displays the status of a specific volume or all volumes.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl status volume
command with the following syntax: srvctl status volume [-device
volume_device
] [-volume
volume_name
]
[-diskgroup
disk_group_name
] [-node "
node_list
"]
Table A-120 srvctl status volume Parameters
Parameter
-device volume_device
Description
Specify the path to the volume device for which you want to display the status.
-volume volume_name
-diskgroup disk_group_name
-node "node_list"
Specify the name of the volume for which you want to view the status.
Specify the name of the disk group in which the volume resides for which you want to display the status.
Specify a comma-delimited list of node names where volumes for which you want to view the status reside.
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stop
Usage Notes
• If you do not specify any of the optional parameters, then SRVCTL displays the status for all volumes.
• If you specify only the
-volume
parameter, then SRVCTL displays the status for the volume that you specify.
• If you specify only the
-diskgroup
parameter, then SRVCTL displays the status for the volumes that reside in the disk group that you specify.
• If you specify only the
-device
parameter, then SRVCTL displays the status for the volume device that you specify.
• If you specify the
-diskgroup
and
-device
parameters, then SRVCTL displays the status for the volume device in the disk group that you specify.
• If you specify the
-node
parameter, then SRVCTL displays the status of the volumes that reside on the nodes you list.
Examples
The srvctl status volume
command displays information similar to the following:
$ srvctl status volume –volume vol1
Volume vol1 of diskgroup diskgrp1 for device volume_device_path1 is enabled
Volume vol1 of diskgroup diskgrp1 for device volume_device_path1 is running
In the preceding example, SRVCTL performs a status query on all nodes because the
node
parameter is not specified.
$ srvctl status volume
Volume vol1 of diskgroup diskgrp for device volume_device_path1 is enabled
Volume vol1 of diskgroup diskgrp for device volume_device_path1 is running
Volume vol2 of diskgroup diskgrp for device volume_device_path2 is enabled
Volume vol2 of diskgroup diskgrp for device volume_device_path2 is running
In the preceding example, SRVCTL displays the status of all registered volumes because the no parameter is specified.
Stops the Oracle Clusterware applications for the database, all or named instances, all or named service names, listeners, or node-level application resources.
Only the Oracle Clusterware applications that are enabled, starting or running are stopped. Objects running outside of Oracle Clusterware are not stopped.
You should disable an object that you intend to remain stopped after you issue a srvctl stop
command. See the srvctl disable
command.
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Note:
• If the object is stopped and is not disabled, then it can restart as the result of another planned operation. The object does not restart because of a failure. Oracle recommends that you disable any object that should remain stopped after you issue a stop
command.
• When you use the
-force
parameter to stop dependent applications and the object, then those dependent applications do not restart when the object is later restarted or after the node fails. You must restart the dependent applications, manually, except for services with AUTOMATIC management policy when a database is stopped.
Table A-121 srvctl stop Summary
Command Description
Stops the cluster database srvctl stop database srvctl stop diskgroup
Stops a specific disk group on a specified number of nodes srvctl stop home
Stops the resources for the specified Oracle home
Stops the instance srvctl stop instance srvctl stop listener
Stops the specified listener or listeners srvctl stop nodeapps
Stops the node-level applications srvctl stop ons srvctl stop scan
Stops Oracle Notification Service
Stops all SCAN VIPs srvctl stop scan_listener
Stops all SCAN listeners srvctl stop service
Stops the service srvctl stop vip
Stops VIP resources srvctl stop volume
Stops a volume device
srvctl stop database
The srvctl stop database
command stops a database, its instances, and its services.
Syntax
srvctl stop database -db db_unique_name [-stopoption stop_options]
[-stopconcurrency number_of_instances] [-drain_timeout timeout] [-eval]
[-force] [-verbose]
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Parameters
Table A-122 srvctl stop database Command Parameters
Parameter Description
-db db_unique_name
Specify the unique name for the database that you want to stop.
-stopoption
stop_options
-stopconcurrency
number_of_instance s
Specify options for the shutdown command, such as
NORMAL
,
TRANSACTIONAL LOCAL
,
IMMEDIATE
, or
ABORT
.
Specify a number of database instances to stop simultaneously, or specify
0
for an empty stop concurrency value.
-drain_timeout
timeout
The time, in seconds, allowed to complete the resource draining action. By default, this parameter is not set. You can specify 0 or any positive integer. An empty string unsets the parameter. If you specify zero, then the agent will perform the actions related to service draining, immediately.
Drain timeout is the maximum time the service waits before exiting (in case of srvctl stop service
or srvctl stop instance
) or proceeding to stop database ( srvctl stop database
), until the draining of sessions is completed. If session draining completes in 10 seconds and the drain timeout value (on
CLI or resource attribute) is 100 seconds, then SRVCTL moves on after 10 seconds. It does not wait for the remaining 90 seconds.
-eval
-force
—verbose
Use this parameter to hypothetically evaluate the impact of the command on the system.
This parameter stops the database, its instances, its services, and any resources that depend on those services.
Display verbose output.
Example
The following command example stops a database and includes verbose output:
$ srvctl stop database -db db1 -drain_timeout 50 -verbose
Draining in progress on services svc1,svc2.
Drain complete on services svc1.
Draining in progress on services svc2.
Draining in progress on services svc2.
Drain complete on services svc2.
srvctl stop diskgroup
Use this command to stop a specific disk group resource on a number of specified nodes.
Syntax and Parameters
Use the srvctl stop diskgroup
command with the following syntax: srvctl stop diskgroup -diskgroup
diskgroup_name
[-node "
node_list
"] [-force]
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Table A-123 srvctl stop diskgroup Parameters
Parameter Description
The Oracle ASM disk group name
-diskgroup diskgroup_name
-node "node_list"
-force
Comma-delimited list of node names on which to stop the disk group resource
Note:
This parameter can be used only with Oracle
Clusterware.
This parameter does not stop the databases that depend on the disk group you are stopping, but instead performs a forceful dismount that may cause those databases to fail.
Example
An example of this command is:
$ srvctl stop diskgroup -diskgroup diskgroup1 -node "mynode1,mynode2" -force
srvctl stop home
Stops all the Oracle Restart-managed or Oracle Clusterware-managed resources that run from the specified Oracle home.
Syntax and Parameters
Use the srvctl stop home
command with the following syntax: srvctl stop home -oraclehome
Oracle_home
-statefile state_file -node
node_name
[-stopoption
stop_options
] [-force]
Table A-124 srvctl stop home Parameters
Parameter
-oraclehome Oracle_home
-statefile state_file
Description
The path to the Oracle home for which you want to start the Oracle Restart or Oracle Clusterware-managed resources.
Note:
The path to the Oracle home you specify must be the same version as the Oracle home from which you invoke SRVCTL.
The path name where you want the state file to be written.
-node node_name
-stopoption stop_options
The name of the node where the Oracle home resides.
Note:
This parameter can be used only with Oracle
Clusterware.
Shutdown options for the database, such as
NORMAL
,
TRANSACTIONAL
,
IMMEDIATE
, or
ABORT
See Also:
SQL*Plus User's Guide and Reference for more information about shutdown options
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Table A-124 (Cont.) srvctl stop home Parameters
Parameter Description
Stop the resources even if errors are reported.
-force
Example
An example of this command is:
$ srvctl stop home -oraclehome /u01/app/oracle/product/12.1.0/db_1 -statefile
~/state.txt
srvctl stop instance
The srvctl stop instance
command stops instances and stops any services running on specified instances.
Syntax
srvctl stop instance -db db_unique_name {-node node_name
| -instance "instance_name_list"} [-stopoption stop_options]
[-drain_timeout timeout] [-force] [-failover] [-verbose]
Parameters
Table A-125 srvctl stop instance Command Parameters
Description Parameter
-db db_unique_name
-node node_name
-instance
"instance_name_lis
t"
-stopoption
stop_options
-drain_timeout
timeout
-force
–failover
-verbose
Usage Notes
If you run this command on an Oracle RAC One Node database, then the command returns an error instructing you to use the srvctl stop database
command, instead.
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SRVCTL Command Reference
Example
The following command example stops instances in an administrator-managed database and includes verbose output:
$ srvctl stop instance -db db1 -instance inst1 -drain_timeout 50 -verbose
Draining in progress on services svc1
Draining in progress on services svc1
Drain complete on services svc1
Related Topics:
SQL*Plus User's Guide and Reference
srvctl stop listener
Stops the default listener or a specific listener on all nodes or the specified node.
You can also use this command to stop a listener on a non-cluster database from the non-cluster database home. However, SRVCTL does not accept the
-node
parameter when run from a non-cluster database home.
Syntax
srvctl stop listener [-listener listener_name] [-node node_name] [-force]
Parameters
Table A-126 srvctl stop listener Command Parameters
Parameter
-listener
listener_name
-node node_name
–force
Description
Specify the name of the listener you want to stop.
If you do not assign a value to this parameter, then SRVCTL stops all known listeners in the cluster.
Optionally, you can specify the name of a single node on which a particular listener runs.
Note:
You can only use this parameter with Oracle Clusterware.
Forcibly stop the listener.
Examples
The following command stops all listeners on the node mynode1
:
$ srvctl stop listener -node mynode1
srvctl stop nodeapps
Stops node-level applications on a node in the cluster.
Note:
This command is only available with Oracle Clusterware.
Server Control Utility Reference A-135
SRVCTL Command Reference
Syntax and Parameters
Use the srvctl stop nodeapps
command with the following syntax: srvctl stop nodeapps [-node node_name] [-gsdonly] [-adminhelper] [-force]
[-relocate] [-verbose]
Table A-127 srvctl stop nodeapps Parameters
Parameter
-node node_name
Description
Node name
If you do not specify this parameter, then the utility stops the node applications (nodeapps) on all active nodes in the cluster.
Stops only the GSD instead of all nodeapps
-gsdonly
-adminhelper
-relocate
Stops only the Administrator helper instead of all nodeapps
Relocate VIP and possibly dependent services
Note:
If you specify this parameter, then you must also specify the
-node node_name
parameter.
Force stop
-force
Display verbose output
-verbose
Example
An example of this command is:
$ srvctl stop nodeapps
srvctl stop ons
Stops the Oracle Notification Service daemon.
Note:
This command is only available with Oracle Restart.
Syntax and Parameters
Use the srvctl stop ons
command with the following syntax: srvctl stop ons [-verbose]
The only parameter for this command is the
-verbose
parameter, which specifies that verbose output should be displayed.
Example
An example of this command is:
$ srvctl stop ons -verbose
A-136 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference
srvctl stop scan
Stops all SCAN VIPs, by default, that are running or in starting state, or stops a specific SCAN VIP identified by
ordinal_number
.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl stop scan
command with the following syntax: srvctl stop scan [-scannumber
ordinal_number
] [-force]
Table A-128 srvctl stop scan Parameters
Parameter
-scannumber ordinal_number
Description
An ordinal number that identifies which SCAN VIP you want to stop. The range of values you can specify for this parameter is 1 to 3.
If you do not specify this parameter, then the utility stops all the SCAN VIPs.
Force stop of the SCAN VIP.
-force
Example
An example of this command is:
$ srvctl stop scan -scannumber 1
srvctl stop scan_listener
Stops all SCAN listeners, by default, that are in a running or starting state, or a specific listener identified by
ordinal_number
.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl start scan_listener
command with the following syntax: srvctl stop scan_listener [-scannumber
ordinal_number
] [-force]
Server Control Utility Reference A-137
SRVCTL Command Reference
Table A-129 srvctl stop scan_listener Parameters
Parameter
-scannumber ordinal_number
Description
An ordinal number that identifies which SCAN listener to stop. You can specify values of 1, 2, or 3 for this parameter.
If you do not specify this parameter, then the utility stops all the SCAN listeners.
Force stop of the SCAN listener.
-force
Example
An example of this command is:
$ srvctl stop scan_listener -scannumber 1
srvctl stop service
The srvctl stop service
command stops one or more services globally across the cluster database, or on the specified instance.
Syntax
srvctl stop service {-node node_name | -db db_unique_name [-pq] [-pdb
pluggable_database |
-service "service_list" [-eval]] [-node node_name | -instance instance_name |}
-serverpool pool_name] [-stopoption IMMEDIATE|TRANSACTIONAL|NONE] [-drain_timeout
timeout]
[-wait {YES | NO}] [-force [-noreplay]] [-global_override] [-verbose]
Parameters
Table A-130 srvctl stop service Command Parameters
Parameter
-node node_name
Description
Optionally, you can specify the name of the node on which you want to stop services. Use this parameter to stop all services on a specific node. Use this parameter for policy-managed databases.
-db db_unique_name
Specify a unique name for the database.
-pdb
pluggable_database
Alternatively, use this parameter to stop services running on a specific pluggable database.
-service
"service_list"
-pq
Specify a particular service or a comma-delimited list of service names enclosed in double quotation marks (
""
) you want to stop.
If you do not provide a service name list, then SRVCTL stops all services on the database or on a specific instance.
Specify this parameter to restrict the stop action to a parallel query service.
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SRVCTL Command Reference
Table A-130 (Cont.) srvctl stop service Command Parameters
Parameter
-instance
instance_name
-serverpool
pool_name
—eval
-stopoption
IMMEDIATE|
TRANSACTIONAL|NONE
Description
Optionally, you can specify the name of the instance for which you want to stop services. Use this parameter for administratormanaged databases.
Optionally, you can specify the name of the server pool that contains the service you want to stop.
Use this parameter to hypothetically evaluate the impact of the command on the system.
Optionally, you can specify the mode in which the service is stopped. If you set this parameter on the service, then this value is used if you do not set the value on the command line.
IMMEDIATE
terminates the sessions after the drain timeout interval expires.
TRANSACTIONAL
permits sessions to drain for the amount of time specified in the
-drain_timeout
parameter. The sessions are then terminated immediately when the drain timeout interval expires.
If you specify
NONE
, then no sessions are terminated.
The default is taken from the service setting, when specified on the service. Otherwise the default is
NONE
.
-drain_timeout
timeout
-wait YES | NO
Specify the time, in seconds, allowed for resource draining to be completed. Accepted values are an empty string (""), 0, or any positive integer. The default value is an empty string, which means that this parameter is not set. If it is set to 0, then draining occurs, immediately.
The draining period is intended for planned maintenance operations. During the draining period, all current client requests are processed, but new requests are not accepted. When set on the service this value is used when the command line value is not set.
Choose
YES
to wait until service draining is completed on the node to stop the service.
Server Control Utility Reference A-139
SRVCTL Command Reference
Table A-130 (Cont.) srvctl stop service Command Parameters
Parameter
-global_override
Description
-force [-noreplay]
Force SRVCTL to stop the service; this causes SRVCTL to disconnect all of the sessions using the stop option you specify
(IMMEDIATE or TRANSACTIONAL), requiring the sessions using the service to reconnect and then connect to another instance.
Notes:
• If you do not specify the
-force
parameter, then sessions already connected to this service stay connected, but new sessions cannot be established to the service.
• Optionally, you can specify the
-noreplay
parameter if you do not want Application Continuity to replay in-flight transactions after a session is terminated.
The
-noreplay
parameter is not limited to use with
-force but
-force
does require
-noreplay
if you do not want to replay in-flight transactions after you force the service to stop.
Override value to operate on a global service. SRVCTL ignores this parameter if the service is not a global service.
-verbose
Use this parameter to display verbose output.
Examples
The following example command stops services running on database db1
:
$ srvctl stop service -db db1 -drain_timeout 60 -force - stopoption immediate verbose
srvctl stop vip
Stops a specific VIP or all VIPs on a specific node, including any VIPs that were relocated due to a failover.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl stop vip
command with the following syntax: srvctl stop vip {-node node_name | -vip vip_name} [-force] [-relocate] [-verbose]
Table A-131 srvctl stop vip Parameters
Parameter
-node node_name
Description
This parameter stops all VIPs on a specific node, including failed-over VIPs
A-140 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference
Table A-131 (Cont.) srvctl stop vip Parameters
Parameter Description
This parameter stops a specific VIP
-vip vip_name
Force SRVCTL to stop the VIP
-force
-relocate
Relocate VIP
Note:
You must use the
-nodenode_name
parameter with the
-relocate
parameter.
Verbose output
-verbose
Example
To stop all the VIPs on mynode1
, including any failed-over VIPs, use the following command:
$ srvctl stop vip -node mynode1 -verbose
srvctl stop volume
Stops a specific, running volume.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl stop volume
command with the following syntax: srvctl stop volume {-volume
volume_name
-diskgroup
disk_group_name
|
-device
volume_device
} [-node "node_list"]
Table A-132 srvctl stop volume Parameters
Parameter Description
Specify the name of the volume to stop.
-volume volume_name
-diskgroup disk_grp_name
Specify the name of the disk group in which the volume to stop resides.
Specify the path to the volume device to stop.
-device volume_device
-node "node_list"
Specify a comma-delimited list of node names where volumes to stop reside.
Server Control Utility Reference A-141
SRVCTL Command Reference
unsetenv
Usage Notes
The srvctl stop volume
command attempts to stop (disable) the volume but it does not disable the resource or remove the volume from Oracle ASM.
Example
The following example stops a volume named
VOLUME1
that resides in a disk group named
DATA
:
$ srvctl stop volume -volume VOLUME1 -diskgroup DATA
The unsetenv
command unsets values for the environment in the configuration file.
It allows users to administer environment configuration for the objects.
Table A-133 srvctl unsetenv Command Summary
Command Description
Unsets the value for one or more cluster database environment variables
Unsets the value for one or more listener environment variables.
Unsets the value for one or more node application environment variables
Unsets the value for one or more VIP environment variables
srvctl unsetenv database
Unsets the cluster database environment configurations.
Syntax and Parameters
Use the srvctl unsetenv database
command as follows: srvctl unsetenv database -db
db_unique_name
-envs "
name_list
"
Table A-134 srvctl unsetenv database Parameters
Parameter Description
Unique name for the database
-db db_unique_name
-envs "name_list"
Comma-delimited list of environment variable names enclosed in double quotation marks (
""
)
Example
The following example unsets the environment configuration for a cluster database environment variable:
$ srvctl unsetenv database -db crm -envs "CLASSPATH,LANG"
A-142 Oracle Real Application Clusters Administration and Deployment Guide
SRVCTL Command Reference
srvctl unsetenv listener
Unsets the environment configuration for a listener.
Syntax and Parameters
Use the srvctl unsetenv listener
command as follows: srvctl unsetenv listener [-listener
listener_name
] -envs "
name_list
"
Table A-135 srvctl unsetenv listener Parameters
Parameter
-listener listener_name
-envs "name_list"
Description
Name of the listener.
If you do not specify this parameter, then the name of the listener defaults to
LISTENER
.
A comma-delimited list of names of environment variables
Example
The following example unsets the environment variable
TNS_ADMIN
for the default listener:
$ srvctl unsetenv listener -envs "TNS_ADMIN"
srvctl unsetenv nodeapps
Unsets the environment configuration for the node applications.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl unsetenv nodeapps
command as follows: srvctl unsetenv nodeapps -envs "
name_list
" [-viponly] [-gsdonly]
[-onsonly] [-verbose]
Table A-136 srvctl unsetenv nodeapps Parameters
Parameter
-envs "name_list"
Description
Comma-delimited list of the names of environment variables enclosed in double quotation marks (
""
)
-viponly
-gsdonly
Modify only the VIP configuration instead of all nodeapps
Modify only the GSD configuration instead of all nodeapps
Server Control Utility Reference A-143
SRVCTL Command Reference
update
Table A-136 (Cont.) srvctl unsetenv nodeapps Parameters
Parameter
-onsonly
Description
Modify only the ONS daemon configuration instead of all nodeapps
Display verbose output
-verbose
Example
The following example unsets the environment configuration for all node applications:
$ srvctl unsetenv nodeapps -envs "test_var1,test_var2"
srvctl unsetenv vip
Unsets the environment configuration for the specified cluster VIP.
Syntax and Parameters
Use the srvctl unsetenv vip
command as follows: srvctl unsetenv vip -vip "
vip_name_list
" -envs "
name_list
" [-verbose]
Table A-137 srvctl unsetenv vip Parameters
Parameter
-vip "vip_name_list"
Description
Comma-delimited list of VIP names enclosed in double quotation marks (
""
)
-envs "name_list"
Comma-delimited list of environment variable names enclosed in double quotation marks (
""
)
Display verbose output
-verbose
Example
The following example unsets the
CLASSPATH
environment variable for a cluster VIP:
$ srvctl unsetenv vip -vip "crm2-vip" -envs "CLASSPATH"
The srvctl update
command requests that the specified running object use the new configuration information stored in the OCR.
Table A-138 srvctl update Command Summary
Command
srvctl update database srvctl update gns
Description
Updates the specified database to use the new listener endpoints
Updates the configuration for GNS
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SRVCTL Command Reference
Table A-138 (Cont.) srvctl update Command Summary
Command
srvctl update listener srvctl update scan_listener
Description
Updates the listener to listen on the new endpoints
Update the SCAN listeners to listen on the new endpoints.
srvctl update database
Updates the specified database to use the new listener endpoints.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl update database
command with the following syntax: srvctl update database -db db_unique_name
Use the
-db
parameter to specify the unique name of the database to update.
srvctl update gns
Use the srvctl update gns
command to modify a Grid Naming Service (GNS) instance.
Note:
This command is only available with Oracle Clusterware.
Syntax and Parameters
Use the srvctl update gns
command with one of these syntax models: srvctl update gns -advertise name -address ip_address [-timetolive time_to_live]
[-verbose] srvctl update gns -delete name [-address address] [-verbose] srvctl update gns -alias alias -name name [-timetolive time_to_live] [-verbose] srvctl update gns -deletealias alias [-verbose] srvctl update gns -createsrv service -target target -protocol protocol
[-weight weight] [-priority priority] [-port port_number]
[-timetolive time_to_live] [-instance instance_name] [-verbose] srvctl update gns -deletesrv service_name -target target -protocol protocol
[-verbose] srvctl update gns -createtxt name -target target [-timetolive time_to_live]
[-namettl name_ttl] [-verbose]
Server Control Utility Reference A-145
SRVCTL Command Reference srvctl update gns -deletetxt name -target target [-verbose] srvctl update gns -createptr name -target target [-timetolive time_to_live]
[-namettl name_ttl] [-verbose] srvctl update gns -deleteptr name -target target [-verbose]
Table A-139 srvctl update gns Parameters
Parameter Description
Advertise a name through GNS
-advertise name
The IP address for an advertised name
-address ip_address
-timetolive time_to_live
Optionally, you can specify, in seconds, an amount of time for the record to live
Remove the advertisement of a name from GNS
-delete name
Create an alias for an advertised name
-alias alias
The advertised name associated with the alias
-name name
Delete an alias
-deletalias alias
Create a service that is described by the record
-createsrv service
Specify a name that is associated with the service
-target target
Specify which protocol is used to connect to the service
-protocol protocol
Specify the weight of the record
-weight weight
-priority priority
-port port_number
Specify the priority of the record, with a value ranging from 0 to 65535
Specify the port number used to connect to the service, with a value ranging from 0 to 65535
Instance name of service
-instance instance_name
Name of the service record to be deleted
-deletesrv service
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SRVCTL Command Reference
Table A-139 (Cont.) srvctl update gns Parameters
Parameter Description
Add a text (TXT) record using the specified name
-createtxt name
Time to live for the name, specified in seconds
-namettl name_ttl
Delete a text (TXT) record of the specified name
-deletetxt name
Add a pointer (PTR) record for the specified name
-createptr name
Delete a pointer (PTR) record for the specified name
-deleteptr name
Usage Notes
You must be logged in as the root
user on Linux and UNIX platforms, or as an
Administrator user on Windows platforms, to run this command.
Example
The following command advertises a name with GNS:
# srvctl update gns -advertise myname -address 192.168.1.45
srvctl update instance
The srvctl update instance
command changes to which Oracle ASM instance or Oracle ASM IOServer the instance connects, or it changes the open mode of the instance.
Syntax
srvctl update instance -db db_unique_name [-instance "instance_name_list"
| -node "node_list"] [-startoption start_options] [-targetinstance instance_name]
Parameters
Parameter Description
-db db_unique_name
Specify the unique name of the database.
-instance
"instance_name_lis
t" | -node
"node_list"
-startoption
start_options
Optionally, you can specify a comma-delimited list of instance names or node names that you want to update. If you specify a list of node names, then SRVCTL udpates the instances running on those specific nodes.
Optionally, you can specify startup options for the database, such as
OPEN
,
MOUNT
, or
"READ ONLY"
.
Server Control Utility Reference A-147
SRVCTL Command Reference
Parameter
-targetinstance
instance_name
Description
Optionally, you can specify a target Oracle ASM or Oracle ASM
IOServer instance. Use double quotation marks (
""
) to specify the default target instance)
Examples
An example of this command is:
$ srvctl update instance -db qdb -node rws1270051 -targetinstance +IOS2
relocate qdb instance on rws1270050 to IOServer instance +IOS2
srvctl update listener
Updates the listener to listen on the new endpoints.
Note:
This command is only available with Oracle Clusterware.
Use the srvctl update listener
command with the following syntax: srvctl update listener
This command does not accept any additional parameters, except for
-help
.
srvctl update scan_listener
Updates the SCAN listeners to listen on the new endpoints.
Note:
This command is only available with Oracle Clusterware.
Use the srvctl update scan_listener
command with the following syntax: srvctl update scan_listener
This command does not accept any additional parameters, except for
-help
.
srvctl upgrade database
The srvctl upgrade database
command upgrades the configuration of a database and all of its services to the version of the database home from where this command is run.
Syntax and Parameters
Use the srvctl upgrade database
command as follows: srvctl upgrade database -db db_unique_name -oraclehome Oracle_home
A-148 Oracle Real Application Clusters Administration and Deployment Guide
Table A-140 srvctl upgrade database Parameters
Parameter Description
Unique name for the database
-db db_unique_name
The path to the
ORACLE_HOME
-oraclehome Oracle_home
SRVCTL Command Reference
Server Control Utility Reference A-149
SRVCTL Command Reference
A-150 Administration and Deployment Guide
B
Troubleshooting Oracle RAC
This appendix explains how diagnose problems for Oracle Real Application Clusters
(Oracle RAC) components using trace and log files. This section includes the following topics:
•
Where to Find Files for Analyzing Errors
•
Managing Diagnostic Data in Oracle RAC
•
Using Instance-Specific Alert Files in Oracle RAC
•
Enabling Tracing for Java-Based Tools and Utilities in Oracle RAC
•
Resolving Pending Shutdown Issues
•
How to Determine If Oracle RAC Instances Are Using the Private Network
•
Database Fails to Start after Private NIC Failure
Note:
Trace and log files, similar to those generated for Oracle Database with Oracle
RAC, are also available for the Oracle Clusterware components. For Oracle
Clusterware, Oracle Database stores these under a unified directory log structure.
See the Oracle Clusterware Administration and Deployment Guide for more information about troubleshooting Oracle Clusterware.
Where to Find Files for Analyzing Errors
Oracle Database records information about important events that occur in your Oracle
RAC environment in trace files. The trace files for Oracle RAC are the same as those in noncluster Oracle databases. As a best practice, monitor and back up trace files regularly for all instances to preserve their content for future troubleshooting.
Information about
ORA-600
errors appear in the
alert_SID.log
file for each instance where SID is the instance identifier.
The alert log and all trace files for background and server processes are written to the
Automatic Diagnostic Repository, the location of which you can specify with the
DIAGNOSTIC_DEST
initialization parameter. For example: diagnostic_dest=/oracle/11.1/diag/rdbms/rac/RAC2/trace
Oracle Database creates a different trace file for each background thread. Oracle RAC background threads use trace files to record database operations and database errors.
These trace logs help troubleshoot and also enable Oracle Support to more efficiently
Troubleshooting Oracle RAC B-1
Managing Diagnostic Data in Oracle RAC debug
configuration problems. The names of trace files are operating system specific, but each file usually includes the name of the process writing the file
(such as LGWR and RECO). For Linux, UNIX, and Windows systems, trace files for the background processes are named
SID_process name
_
process
identifier.trc
.
See Also:
Oracle Database Administrator's Guide
and Oracle Database 2 Day + Real
Application Clusters Guide
for more information about monitoring errors and alerts in trace files
Trace files are also created for user processes if you set the
DIAGNOSTIC_DEST initialization parameter. User process trace file names have the format
SID_ora_process_identifier/thread_identifier
.
trc
, where
process_identifier
is a 5-digit number indicating the process identifier (PID) on
Linux and UNIX systems, and
thread_identifier
is the thread identifier on
Windows systems.
Managing Diagnostic Data in Oracle RAC
Problems that span Oracle RAC instances can be the most difficult types of problems to diagnose.
For example, you may need to correlate the trace files from across multiple instances, and merge the trace files. Oracle Database 12c release 2 (12.2) includes an advanced fault diagnosability infrastructure for collecting and managing diagnostic data, and uses the Automatic Diagnostic Repository (ADR) file-based repository for storing the database diagnostic data. When you create the ADR base on a shared disk, you can place ADR homes for all instances of the same Oracle RAC database under the same
ADR Base. With shared storage:
• You can use the ADRCI command-line tool to correlate diagnostics across all instances.
ADRCI is a command-line tool that enables you to view diagnostic data in the
ADR and package incident and problem information into a zip file for transmission to Oracle Support. The diagnostic data includes incident and problem descriptions, trace files, dumps, health monitor reports, alert log entries, and so on.
See Also:
Oracle Database Utilities
for information about using ADRCI
• You can use the Data Recovery Advisor to help diagnose and repair corrupted data blocks, corrupted or missing files, and other data failures.
The Data Recovery Advisor is an Oracle Database infrastructure that automatically diagnoses persistent data failures, presents repair options, and repairs problems at your request.
B-2 Oracle Real Application Clusters Administration and Deployment Guide
Using Instance-Specific Alert Files in Oracle RAC
See Also:
Oracle Database Administrator’s Guide
for information about managing diagnostic data
Using Instance-Specific Alert Files in Oracle RAC
Each instance in an Oracle RAC database has one alert file. The alert file for each instance,
alert.SID.log
, contains important information about error messages and exceptions that occur during database operations. Information is appended to the alert file each time you start the instance. All process threads can write to the alert file for the instance.
The
alert_SID.log
file is in the directory specified by the
DIAGNOSTIC_DEST initialization parameter.
Enabling Tracing for Java-Based Tools and Utilities in Oracle RAC
All Java-based tools and utilities that are available in Oracle RAC are called by executing scripts of the same name as the tool or utility.
This includes the Cluster Verification Utility (CVU), Database Configuration Assistant
(DBCA), the Net Configuration Assistant (NETCA), Server Control Utility (SRVCTL), and the
. For example, to run DBCA, enter the
command dbca
.
By default, Oracle Database enables traces for DBCA and the Database Upgrade
Assistant (DBUA). For the CVU, GSDCTL, and SRVCTL, you can set the
SRVM_TRACE environment variable to
TRUE
to make Oracle Database generate traces. Oracle
Database writes traces to log files. For example, Oracle Database writes traces to log files in
Oracle_base/cfgtoollogs/dbca
and
Oracle_base/cfgtoollogs/ dbua
for DBCA and DBUA, respectively.
Resolving Pending Shutdown Issues
In some situations a
SHUTDOWN IMMEDIATE
may be pending and Oracle Database will not quickly respond to repeated shutdown requests. This is because Oracle
Clusterware may be processing a current shutdown request. In such cases, issue a
SHUTDOWN ABORT
using SQL*Plus for subsequent shutdown requests.
How to Determine If Oracle RAC Instances Are Using the Private Network
This section describes how to manually determine if Oracle RAC instances are using the private network. However, the best practice for this task is to use the Oracle
Enterprise Manager Cloud Control graphical user interface (GUI) to check the interconnect. Also, see the Oracle Database 2 Day + Real Application Clusters Guide for more information about monitoring Oracle RAC using Oracle Enterprise Manager.
With most network protocols, you can issue the oradebug ipc
command to see the interconnects that the database is using. For example: oradebug setmypid oradebug ipc
These commands dump a trace file to the location specified by the
DIAGNOSTIC_DEST
initialization parameter. The output may look similar to the following:
Troubleshooting Oracle RAC B-3
Database Fails to Start after Private NIC Failure
SSKGXPT 0x1a2932c flags SSKGXPT_READPENDING info for network 0
socket no 10 IP 172.16.193.1 UDP 43749
sflags SSKGXPT_WRITESSKGXPT_UP info for network 1
socket no 0 IP 0.0.0.0 UDP 0...
In the example, you can see the database is using IP 172.16.193.1 with a User Datagram
Protocol (UDP) protocol. Also, you can issue the oradebug tracefile_name command to print the trace location where the output is written.
Additionally, you can query the
V$CLUSTER_INTERCONNECTS
view to see information about the private interconnect. For example:
SQL> SELECT * FROM V$CLUSTER_INTERCONNECTS;
NAME IP_ADDRESS IS_ SOURCE
----- -------------------------- --- ------------------------------eth0 138.2.236.114 NO Oracle Cluster Repository
Database Fails to Start after Private NIC Failure
In a two-node cluster that is not using grid interprocess communication (GIPC) and has only a single private network interface card (NIC), when the NIC fails on the node on which the Oracle Grid Infrastructure Management Repository database (mgmtdb) is running (node A, for example) after the other node (node B) was evicted, then when the private network is reestablished on node A, node B joins the cluster but the database instance on node A is unable to start.
To start the database instance:
1.
Stop the Oracle Clusterware stack on both nodes, as follows:
2.
3.
4.
crsctl stop cluster
Start the Oracle Clusterware stack on both nodes, as follows: crsctl start cluster
Stop the database instance on node A, on which the NIC failed, as follows: srvctl stop instance -db db_unique_name -node A
Start the database on both nodes by running the following commands one of the nodes: srvctl start instance -db db_unique_name -node B srvctl start instance -db db_unique_name -node A
The database instance will fail to start on node A until after the instance starts on node B.
B-4 Oracle Real Application Clusters Administration and Deployment Guide
Glossary
Automatic Workload Repository (AWR)
A built-in repository that exists in every Oracle database. At regular intervals, Oracle
Database makes a snapshot of all of its vital statistics and workload information and stores them in the AWR.
administrator-managed database
A database that you specifically define on which servers it can run, and where services can run within the database.
cache coherency
The synchronization of data in multiple caches so that reading a memory location through any cache will return the most recent data written to that location through any other cache. Sometimes called cache consistency.
Cache Fusion
A diskless cache coherency mechanism in Oracle RAC that provides copies of blocks directly from a holding instance's memory cache to a requesting instance's memory cache.
cardinality
The number of database instances you want running during normal operations.
CDB client cluster
A cluster that advertises its names with the
cluster
A multitenant container database (CDB) is an Oracle database that includes zero, one, or many user-created pluggable databases (
s). Every Oracle database is either a
CDB or a non-CDB.
Multiple interconnected computers or servers that appear as if they are one server to end users and applications.
Glossary-1
cluster configuration policy
cluster configuration policy
A document that contains exactly one definition for each server pool defined in the system.
cluster configuration policy set
A document that defines the names of all server pools configured in the cluster and contains one or more configuration policies.
cluster database
The generic term for a Oracle RAC database.
cluster file system
A distributed file system that is a cluster of servers that collaborate to provide high performance service to their clients. Cluster file system software deals with distributing requests to storage cluster components.
Cluster Ready Services Daemon (CRSD)
The primary Oracle Clusterware process that performs high availability recovery and management operations, such as maintaining OCR. Also manages application resources and runs as root
user (or by a user in the admin
group on Mac OS X-based systems) and restarts automatically upon failure.
Cluster Synchronization Services (CSS)
An Oracle Clusterware component that discovers and tracks the membership state of each node by providing a common view of membership across the cluster. CSS also monitors process health, specifically the health of the database instance. The Global
Enqueue Service Monitor (LMON), a background process that monitors the health of the cluster database environment and registers and de-registers from CSS. See also,
OCSSD.
Cluster Time Synchronization Service
A time synchronization mechanism that ensures that all internal clocks of all nodes in a cluster are synchronized.
Cluster Verification Utility (CVU)
A tool that verifies a wide range of Oracle RAC components such as shared storage devices, networking configurations, system requirements, Oracle Clusterware, groups, and users.
commit outcome
A message sent to the client from the Oracle database after a transaction has been committed. These messages are not durable.
Glossary-2
Fast Connection Failover
database pool
A set of databases within a database cloud that provide a unique set of global services and belong to a certain administrative domain. Partitioning of cloud databases into multiple pools simplifies service management and provides higher security because each pool can be administered by a different administrator.
Distributed Transaction Processing (DTP)
The paradigm of distributed transactions, including both XA-type externally coordinated transactions, and distributed-SQL-type (database links in Oracle) internally coordinated transactions.
dynamic network
A network that uses DHCP for IPv4 or stateless autoconfiguration (autoconfig) for
IPv6.
Event Manager (EVM)
The background process that publishes Oracle Clusterware events. EVM scans the designated callout directory and runs all scripts in that directory when an event occurs.
Event Manager Daemon (EVMD)
A Linux or UNIX event manager daemon that starts the racgevt
process to manage callouts.
failure group
A failure group is a subset of the disks in a disk group, which could fail at the same time because they share hardware. Failure groups are used to store mirror copies of data.
Fast Application Notification (FAN)
Applications can use FAN to enable rapid failure detection, balancing of connection pools after failures, and re-balancing of connection pools when failed components are repaired. The FAN notification process uses system events that Oracle Database publishes when cluster servers become unreachable or if network interfaces fail.
Fast Connection Failover
Fast Connection Failover provides high availability to FAN integrated clients, such as clients that use JDBC, OCI, or ODP.NET. If you configure the client to use fast connection failover, then the client automatically subscribes to FAN events and can react to database
UP
and
DOWN
events. In response, Oracle Database gives the client a connection to an active instance that provides the requested database service.
Glossary-3
file system
file system
A file system is a software component providing structured access to disks. File systems present objects, such as files, to application programs. Access to files is generally specified with standard API defining operating system calls such as Open/
Close and Read/Write that the application program uses for accessing files. File systems are usually provided as a component of an operating system, but may be provided as an independent software component.
forced disk write
In Oracle RAC, a particular data block can only be modified by one instance at a time.
If one instance modifies a data block that another instance needs, then whether a forced disk write is required depends on the type of request submitted for the block.
General Parallel File System (GPFS)
General Parallel File System (GPFS) is a shared-disk IBM file system product that provides data access from all of the nodes in a homogenous or heterogeneous cluster.
Global Cache Service (GCS)
Process that implements Cache Fusion. It maintains the block mode for blocks in the global role. It is responsible for block transfers between instances. The Global Cache
Service employs various background processes such as the Global Cache Service
Processes (LMSn) and Global Enqueue Service Daemon (LMD).
Global Cache Service Processes (LMSn)
Processes that manage remote messages. Oracle RAC provides for up to 10 Global
Cache Service Processes.
Global Cache Service (GCS) resources
Global resources that coordinate access to data blocks in the buffer caches of multiple
Oracle RAC instances to provide cache coherency.
global database name
The full name of the database that uniquely identifies it from any other database. The global database name is of the form
database_name.database_domain
—for example:
OP.US.FOO.COM
global dynamic performance views (GV$)
Dynamic performance views storing information about all open instances in an Oracle
RAC cluster. (Not only the local instance.) In contrast, standard dynamic performance views (
V$
) only store information about the local instance.
Global Enqueue Service (GES)
A service that coordinates enqueues that are shared globally.
Glossary-4
instance
Global Enqueue Service Daemon (LMD)
The resource agent process that manages requests for resources to control access to blocks. The LMD process also handles deadlock detection and remote resource requests. Remote resource requests are requests originating from another instance.
Global Enqueue Service Monitor (LMON)
The background LMON process monitors the entire cluster to manage global resources. LMON manages instance deaths and the associated recovery for any failed instance. In particular, LMON handles the part of recovery associated with global resources. LMON-provided services are also known as Cluster Group Services.
Global Services Daemon (GSD)
A component that receives requests from SRVCTL to execute administrative job tasks, such as startup or shutdown. The command is executed locally on each node, and the results are returned to SRVCTL. GSD is installed on the nodes by default.
Grid Plug and Play Daemon (GPNPD)
This process provides access to the Grid Plug and Play profile, and coordinates updates to the profile among the nodes of the cluster to ensure that all of the nodes node have the most recent profile.
High Availability Cluster Multi-Processing (HACMP)
High Availability Cluster Multi-Processing is an IBM AIX-based high availability cluster software product. HACMP has two major components: high availability (HA) and cluster multi-processing (CMP).
high availability
Systems with redundant components that provide consistent and uninterrupted service, even if there are hardware or software failures. This involves some degree of redundancy.
Hub Node
that is tightly connected with other servers and has direct access to shared storage.
instance
For an Oracle RAC database, each node in a cluster usually has one instance of the running Oracle software that references the database. When a database is started,
Oracle Database allocates a memory area called the System Global Area (SGA) and starts one or more Oracle Database processes. This combination of the SGA and the
Oracle Database processes is called an instance. Each instance has unique Oracle
System Identifier (SID), instance name, rollback segments, and thread ID.
Glossary-5
instance caging
instance caging
A method that uses an initialization parameter to limit the number of CPUs that an instance can use simultaneously for foreground processes.
instance membership recovery
The method used by Oracle RAC guaranteeing that all cluster members are functional or active. instance membership recovery polls and arbitrates the membership. Any members that do not show a heartbeat by way of the control file or who do not respond to periodic activity inquiry messages are presumed terminated.
instance name
Represents the name of the instance and is used to uniquely identify a specific instance when clusters share common services names. The instance name is identified by the
INSTANCE_NAME
parameter in the instance initialization file, initsid.ora
. The instance name is the same as the Oracle System Identifier (SID).
instance number
A number that associates extents of data blocks with particular instances. The instance number enables you to start an instance and ensure that it uses the extents allocated to it for inserts and updates. This will ensure that it does not use space allocated for other instances.
interconnect
The communication link between nodes.
keystore
A container that stores a Transparent Data Encryption key. In previous releases, this was referred to as a wallet.
Leaf Node
Servers that are loosely coupled with
s, which may not have direct access to the shared storage.
Logical Volume Manager (LVM)
A generic term that describes Linux or UNIX subsystems for online disk storage management.
Interprocess Communication (IPC)
A high-speed operating system-dependent transport component. The IPC transfers messages between instances on different nodes. Also referred to as the interconnect.
Glossary-6
Object Link Manager (OLM)
Master Boot Record (MBR)
A program that executes when a computer starts. Typically, the MBR resides on the first sector of a local hard disk. The program begins the startup process by examining the partition table to determine which partition to use for starting the system. The
MBR program then transfers control to the boot sector of the startup partition, which continues the startup process.
memory pressure
A state indicating that there is a limited amount of available memory on a server.
metric
The rate of change in a cumulative statistic.
multitenant container database
See
.
mutables
Non-deterministic functions that can change their results each time they are called.
Mutable functions can cause replay to be rejected, if the function results change at replay. Consider
sequence.nextval
and SYSDATE used in key values. If a primary key is built with values from these function calls, and is used in later foreign keys or other binds, then, at replay the same function result must be returned. Application
Continuity provides mutable value replacement at replay for granted Oracle function calls to provide opaque bind-variable consistency.
Network Attached Storage (NAS)
Storage that is attached to a server by way of a network.
Network Time Protocol (NTP)
An Internet standard protocol, built on top of TCP/IP, that ensures the accurate synchronization to the millisecond of the computer clock times in a network of computers.
Network Interface Card (NIC)
A card that you insert into a computer to connect the computer to a network.
node
A node is a computer system on which Oracle RAC and Oracle Clusterware software are installed.
Object Link Manager (OLM)
The Oracle interface that maps symbolic links to logical drives and displays them in the OLM graphical user interface.
Glossary-7
OCSSD
OCSSD
A Linux or UNIX process that manages the Cluster Synchronization Services (CSS) daemon. Manages cluster node membership and runs as oracle
user; failure of this process results in cluster restart.
Oracle Cluster File Systems
Oracle offers two cluster file systems, OCFS2 for Linux and Oracle ASM Cluster File
System (Oracle ACFS). While Oracle ACFS is a proprietary file system, the source for
OCFS2 for Linux is available to all under GNUs' General Public License (GPL). The two file systems are not compatible.
Oracle Cluster Registry (OCR)
The Oracle RAC configuration information repository that manages information about the cluster node list and instance-to-node mapping information. OCR also manages information about Oracle Clusterware resource profiles for customized applications.
Oracle Clusterware
This is clusterware that is provided by Oracle to manage cluster database processing including node membership, group services, global resource management, and high availability functions.
Oracle Extended Cluster
A cluster consist of nodes that are located in multiple locations called sites.
Oracle Flex Cluster
Large clusters that are made of up of two types of nodes:
where the Hub Nodes form a cluster using current membership algorithms and Leaf
Nodes connect for membership to a single Hub Node.
Oracle Grid Infrastructure
The software that provides the infrastructure for an enterprise grid architecture. In a cluster this software includes Oracle Clusterware and Oracle Automatic Storage
Management (Oracle ASM). For a standalone server, this software includes Oracle
Restart and Oracle ASM. Oracle Database combines these infrastructure products into one software installation called the Oracle Grid Infrastructure home (
Grid_home
).
Oracle Grid Naming Service Daemon (GNSD)
The Oracle Grid Naming Service is a gateway between the cluster mDNS and external
DNS servers. The gnsd
process performs name resolution within the cluster.
Oracle High Availability Services Daemon (OHASD)
This process anchors the lower part of the Oracle Clusterware stack, which consists of processes that facilitate cluster operations.
Glossary-8
raw device
Oracle Interface Configuration Tool (OIFCFG)
A command-line tool for both noncluster Oracle databases and Oracle RAC databases that enables you to allocate and de-allocate network interfaces to components, direct components to use specific network interfaces, and retrieve component configuration information. The Oracle Universal Installer also uses OIFCFG to identify and display available interfaces.
Oracle Managed Files
A service that automates naming, location, creation, and deletion of database files such as control files, redo log files, data files and others, based on a few initialization parameters. You can use Oracle Managed Files on top of a traditional file system supported by the host operating system, for example, VxFS or ODM. It can simplify many aspects of the database administration by eliminating the need to devise your own policies for such details.
Oracle Notification Service
A publish and subscribe service for communicating information about all FAN events.
Oracle Universal Installer
A tool to install Oracle Clusterware, the Oracle relational database software, and the
Oracle RAC software. You can also use the Oracle Universal Installer to launch the
Database Configuration Assistant (DBCA).
Oracle XA
An external interface that allows global transactions to be coordinated by a transaction manager other than Oracle Database.
PDB
In a multitenant container database (
), a portable collection of schemas, schema
objects, and nonschema objects that appears to an Oracle Net client as a non-CDB.
pluggable database
See
policy-managed database
A database that you define as a cluster resource. Management of the database is defined by how you configure the resource, including on which servers the database can run and how many instances of the database are necessary to support the expected workload.
raw device
A disk drive that does not yet have a file system set up. Raw devices are used for
Oracle RAC because they enable the sharing of disks. See also
.
Glossary-9
raw partition
raw partition
A portion of a physical disk that is accessed at the lowest possible level. A raw partition is created when an extended partition is created and logical partitions are assigned to it without any formatting. Once formatting is complete, it is called a cooked partition. See also raw device.
recoverable error
A class of errors that arise due to an external system failure, independent of the application session logic that is executing. Recoverable errors occur following planned and unplanned outages of foregrounds, networks, nodes, storage, and databases. The application receives an error code that can leave the application not knowing the status of the last operation submitted.
Recovery Manager (RMAN)
An Oracle tool that enables you to back up, copy, restore, and recover data files, control files, and archived redo logs. It is included with the Oracle server and does not require separate installation. You can run RMAN as a command line utility from the operating system (O/S) prompt or use the GUI-based Oracle Enterprise Manager
Backup Manager.
region
A logical boundary that contains database clients and servers that are considered to be close to each other.
request
A unit of work submitted from the application. A request typically corresponds to the
SQL and PL/SQL, and other database calls of a single web request, on a single database connection, and generally is demarcated by the calls made to check-out and check-in the database connection from a connection pool.
result cache
A result cache is an area of memory, either in the SGA or client application memory, that stores the result of a database query or query block for reuse. The cached rows are shared across statements and sessions unless they become stale.
Runtime Connection Load Balancing
Enables Oracle Database to make intelligent service connection decisions based on the connection pool that provides the optimal service for the requested application based on current workloads. The JDBC, ODP.NET, and OCI clients are integrated with the load balancing advisory; you can use any of these client environments to provide runtime connection load balancing.
scalability
The ability to add additional nodes to Oracle RAC applications and achieve markedly improved scale-up and speed-up.
Glossary-10
session state consistency
Secure Shell (SSH)
A program for logging into a remote computer over a network. You can use SSH to execute commands on a remote system and to move files from one system to another.
SSH uses strong authentication and secure communications over insecure channels.
Server Control Utility (SRVCTL)
Server Management (SRVM) comprises the components required to operate Oracle
Enterprise Manager in Oracle RAC. The SRVM components, such as the Intelligent
Agent, Global Services Daemon, and SRVCTL, enable you to manage cluster databases running in heterogeneous environments through an open client/server architecture using Oracle Enterprise Manager.
server
A computer system that has no Oracle software installed upon it.
server cluster
The cluster in which the shared GNS server is running.
server group
A logical partition of nodes in a cluster into a group that hosts applications, databases, or both. Server groups can be members of other server groups.
service level
A measure of the performance of a system.
services
Entities that you can define in Oracle RAC databases that enable you to group database workloads and route work to the optimal instances that are assigned to offer the service.
session state consistency
After a COMMIT has executed, if the state was changed in that transaction, then it is not possible to replay the transaction to reestablish that state if the session is lost.
When configuring Application Continuity, the applications are categorized depending on whether the session state after the initial setup is dynamic or static, and then whether it is correct to continue past a COMMIT operation within a request.
•
Dynamic
: (default) A session has dynamic state if the session state changes are not fully encapsulated by the initialization, and cannot be fully captured in a callback at failover. Once the first transaction in a request commits, failover is internally disabled until the next request begins. This is the default mode that most applications should use for requests.
•
Static
: (special—on request) A session has a static state if all session state changes, such as NLS settings and PL/SQL package state, can be repeated in an initialization callback. This setting is used only for database diagnostic
Glossary-11
shared everything applications that do not change session state inside requests. Do not set STATIC mode if there are any non-transactional state changes in the request that cannot be reestablished by a callback. If you are unsure, use DYNAMIC mode.
shared everything
A database architecture in which all instances share access to all of the data.
single client access name (SCAN)
Oracle Database 11g database clients use SCAN to connect to the database. SCAN can resolve to multiple IP addresses, reflecting multiple listeners in the cluster handling public client connections.
singleton services
Services that run on only one instance at any one time. By defining the Distributed
Transaction Property (DTP) property of a service, you can force the service to be a singleton service.
split brain syndrome
Where two or more instances attempt to control a cluster database. In a two-node environment, for example, one instance attempts to manage updates simultaneously while the other instance attempts to manage updates.
SQL translation profile
A SQL translation profile is a database schema object that directs how SQL statements in non-Oracle databases are translated to Oracle, and how Oracle error codes and
ANSI SQLSTATES are translated into other vendors' equivalents.
system identifier (SID)
The Oracle system identifier (SID) identifies a specific instance of the running Oracle software. For an Oracle RAC database, each node within the cluster has an instance referencing the database.
transparent application failover (TAF)
A runtime failover for high-availability environments, such as Oracle RAC and Oracle
RAC Guard, TAF refers to the failover and re-establishment of application-to-service connections. It enables client applications to automatically reconnect to the database if the connection fails, and optionally resume a SELECT statement that was in progress.
This reconnect happens automatically from within the Oracle Call Interface library.
Virtual Internet Protocol (VIP)
An IP address assigned to multiple applications residing on a single server, multiple domain names, or multiple servers, rather than being assigned to a specific single server or network interface card (NIC).
Glossary-12
volume manager
A volume manager is a software component that manages the mapping of the collection of the pieces of the disks into a volume.
voting disk
A file that manages information about node membership.
voting disk
Glossary-13
Symbols
$ORACLE_HOME/root.sh script,
A
abnormal instance termination,
ACMS
Atomic Controlfile to Memory Service,
Active Session History
Top Remote Instance,
active sessions,
ACTIVE_INSTANCE_COUNT initialization
adding nodes to an existing cluster,
adding Oracle RAC to nodes on Linux and UNIX,
adding Oracle RAC to nodes on Windows,
ADDM
global monitoring,
see
Automatic Database Diagnostic Monitor,
ADDM for Oracle Real Application Clusters mode,
administering
administering instances
administering Oracle Enterprise Manager jobs,
administering services
Oracle Enterprise Manager,
SRVCTL,
administrative tools
administrator-managed database
administrator-managed database instances
administrator-managed databases
AVAILABLE instances for services,
PREFERRED instances for services,
Index
ADRCI
Advanced Queuing and FAN,
Advisor Central in Oracle Enterprise Manager,
aggregates
by services, by waits,
alert administration
alert blackouts
alert logs
ALTER SYSTEM ARCHIVE LOG CURRENT statement,
ALTER SYSTEM ARCHIVE LOG statement
ALTER SYSTEM CHECKPOINT statement global versus local,
ALTER SYSTEM KILL SESSION statement terminating a session on a specific instance,
ALTER SYSTEM QUIESCE RESTRICTED statement quiescing a noncluster database,
ALTER SYSTEM statement
CHECKPOINT clause,
ALTER SYSTEM SWITCH LOGFILE statement,
Application Continuity commit outcome,
configuring service attributes,
delaying reconnection,
dynamic session state consistency,
establishing initial state,
potential side effects, recoverable error,
Index-1
Application Continuity (continued)
running without,
session state consistency,
static session state consistency,
using for planned maintenance,
applications consolidating multiple in a single database,
spanning XA transactions across Oracle RAC
using pre-created database sessions,
ARCHIVE LOG command
SQL*Plus, archive logs
destinations, converting to cluster database,
ARCHIVE_LAG_TARGET initialization parameter,
archived redo log files
file format and destination,
archiver process
monitor, archiving mode
ASH reports,
ASM_PREFERRED_READ_FAILURE_GROUPS
Atomic Controlfile to Memory Service (ACMS),
Automatic Database Diagnostic Monitor (ADDM) analyzing AWR data,
DBMS_ADDM PL/SQL package,
Local ADDM mode,
Automatic Diagnostic Repository (ADR)
ADRCI command-line interpreter,
automatic load balancing configuring RMAN channels for multiple
AUTOMATIC management policy,
Automatic Performance Diagnostics (AWR) monitor performance statistics,
automatic segment space management (ASSM) tablespace use in Oracle RAC,
automatic undo management tablespace use in Oracle RAC,
automatic workload management concepts,
,
Automatic Workload Repository (AWR) monitoring performance,
AVAILABLE instances
Index-2
AVAILABLE instances (continued) for services,
Average Active Sessions chart
AWR
see
Automatic Workload Repository (AWR),
B
background processes
Oracle RAC,
SMON,
background thread trace files,
backups
and converting to cluster database,
bandwidth
best practices
deploying Oracle RAC for high availability,
blackouts
block mode conversions statistics for, blocks
associated with instance, buffer cache instance recovery, buffer sizes
interprocess communication (IPC)
C
Cache Fusion
callouts
how they are run, capacity
cardinality,
catclustdb.sql script,
changing the configuration of all services,
channels configure one RMAN channel for each Oracle
RAC instance,
configuring during crosscheck or restore
configuring for RMAN, charts
Cluster Host Load Average,
charts (continued)
Database Throughput,
Global Cache Block Access Latency,
client drivers
clients application environments and FAN,
clone.pl,
clone.pl script cloning parameters,
cloning
parameters passed to the clone.pl script,
running $ORACLE_HOME/root.sh script,
cluster
cluster configuration policy set,
Cluster Database Performance page
Top Activity drill down menu, cluster databases
creating using DBCA, cluster file system archiving parameter settings,
restore,
Cluster Host Load Average page
cluster nodes name in clone.pl script,
Cluster Verification Utility
CLUSTER_DATABASE initialization parameter,
CLUSTER_DATABASE_INSTANCES initialization
CLUSTER_INTERCONNECTS
CLUSTER_INTERCONNECTS initialization
clustered Oracle ASM converting a noncluster Oracle ASM,
clusters consolidating multiple databases in,
policy-managed,
clusterware management solution,
cold backups,
comma-delimited lists with SRVCTL,
command-line interpreter
ADR Command-Line Interpreter (ADRCI),
committed data instance failure,
communication protocols verifying settings for,
compatibility
Oracle RAC and Oracle Database software,
COMPATIBLE initialization parameter,
configuring channels during restore or crosscheck operations,
configuring preferred mirror read disks in extended clusters,
CONNECT command
CONNECT SYS
connecting to instances,
connection load balancing
connection pools and FAN,
container databases
See
CONTROL_FILES initialization parameter,
convert to cluster database from single-instance to Oracle Real Application
post-conversion,
to Oracle RAC from single-instance databases,
convert to Oracle RAC database
converting
from single instance to Oracle RAC,
from single-instance to Oracle Real Application
converting a database from Oracle RAC One Node to
Oracle RAC,
converting an Oracle RAC database with one instance
to Oracle RAC One Node,
CREATE PFILE
CREATE PFILE statement,
CREATE SPFILE
creating
server parameter files,
Index-3
creating (continued)
SPFILE backups, crosscheck operations
configuring channels during, crosschecking on multiple nodes
CRS resources
management of,
current blocks,
CVU
D
data dictionary
data security keystore,
data warehouse deploying applications for in Oracle RAC,
database administrative privilege
services singleton,
uniform,
Database Configuration Assistant (DBCA) adding and deleting instances in interactive mode
adding and deleting instances in silent mode
adding instances in interactive mode
adding instances in silent mode
creating views for Oracle Real Application
deleting instances in interactive mode
deleting instances in silent mode
Instance Management page,
,
List of Cluster Databases page,
running the catclustdb.sql script,
Welcome page,
database deployment administrator-managed,
,
policy-managed,
,
database instances administrator managed
Index-4
database instances (continued) administrator managed (continued) deleting,
connecting to, database pools,
database resource,
Database Resource Manager,
Database Throughput page
databases administrator managed,
consolidating multiple in a cluster,
creating
Oracle RAC One Node,
Oracle RAC One Node
policy managed,
databases sessions
DB_BLOCK_SIZE initialization parameter,
DB_DOMAIN initialization parameter,
DB_FILES initialization parameter,
DB_NAME initialization parameter,
DB_RECOVERY_FILE_DEST initialization parameter,
DB_RECOVERY_FILE_DEST_SIZE initialization parameter,
DB_UNIQUE_NAME initialization parameter,
DDL statements,
deleting administrator-managed database instances,
dependencies and services, deploying
Oracle Real Application Clusters environments,
design
Oracle Real Application Clusters environments,
diagnosing problems for Oracle RAC,
diagnosing problems using ADR,
DISPATCHERS initialization parameter specifying a service with,
Distributed Transaction Processing (DTP),
distributed transactions directing to a single instance in the cluster,
XA transactions span instances,
DML_LOCKS initialization parameter,
DTP
DTP (continued) services
XA affinity,
XA transactions,
DTP service.,
dynamic database services
Dynamic Database Services introduction to,
dynamic performance views creating,
GV$,
dynamic resource allocation overview,
dynamic session state consistency,
E
e-commerce applications in Oracle RAC,
edition services attribute,
ENCRYPTION_WALLET_LOCATION parameter,
Enterprise Manager overview,
environment variables
passed to the clone.pl script,
event notification enabling,
extended distance cluster
Oracle ASM preferred mirror read,
extended distance clusters configuring preferred mirror read disks,
extending Oracle database home on shared storage
Oracle ACFS,
external transaction managers
OraMTS,
F
failure instance,
multiple node,
node,
FAN
Fast Application Notification (FAN)
Fast Application Notification (FAN)
callouts
Fast Application Notification (FAN) (continued) callouts (continued)
events
enabling for JDBC,
enabling for JDBC-thin clients, enabling for OCI,
HA events,
how events are published,
introduction,
parameters and matching database signatures,
Fast Connection Failover (FCF)
enabling with thin and thick clients,
Fast Recovery
and files managed by Oracle, fault diagnosability,
FCF
See
Fast Connection Failover (FCF)
files
redo log,
FROM MEMORY clause
on CREATE PFILE or CREATE SPFILE,
G
GC_SERVER_PROCESSES initialization parameter
specifying the number of LMSn processes,
GCS_SERVER_PROCESSES initialization parameter,
Generic server pool,
GES
See
global cache and enqueue service (GES)
global cache and enqueue service (GES),
Global Cache Block Access Latency chart
Global Cache Service (GCS),
,
Global Cache Service Process (LMS),
Global Cache Service Processes (LMSn) reducing the number of,
specifying the number of,
Global Cache Service statistics,
,
GLOBAL clause forcing a checkpoint,
Global Enqueue Service Daemon (LMD),
Global Enqueue Service Monitor (LMON),
Global Enqueue Service statistics, global performance data
Index-5
global performance data (continued) with ADDM,
Global Resource Directory (GRD), global service attributes
GDSCTL,
Global Transaction Process (GTX0-j),
GLOBAL_TXN_PROCESSES initialization parameter,
goals and the load balancing advisory,
for load balancing advisory,
GTX0-j
GV$,
H
Hang Manager,
hash partitioning
high availability
best practices,
for Oracle RAC Databases, high availability framework introduction to,
HOST command
SQL*Plus,
I
idempotence,
idle wait class,
IM column store
In-Memory Column Store and Oracle RAC,
overview,
In-Memory FastStart, indexes sequence-based,
initialization parameters
cluster database issues regarding,
CLUSTER_INTERCONNECTS
identical settings for on all instances,
RECOVERY_PARALLELISM,
that must be identical on all instances,
that must be unique on all instances,
installations
performing multiple simultaneous cluster,
instance
Index-6
instance (continued)
SRVCTL object name, instance discovery
Oracle Enterprise Manager Cloud Control,
Instance Enqueue Process (LCK0),
INSTANCE NAME initialization parameter,
instance recovery,
INSTANCE_NAME initialization parameter,
INSTANCE_NUMBER initialization parameter,
INSTANCE_TYPE initialization parameter,
instances
aggregated for service performance,
cloning Oracle RAC,
effect of SQL*Plus commands on,
initialization parameter settings,
maximum number for Oracle RAC,
memory structures, parallel processes,
,
recovery, abnormal shutdown,
recovery, multiple failures,
Server Management,
starting and stopping,
verifying,
verifying running,
instances failure recovery from,
instead of Statspack,
interconnect
and the Oracle RAC architecture,
defined,
verifying settings for, interconnect bandwidth
interconnect block transfer rates,
interconnect settings verifying, interconnects
alternatives to the private network, private,
Interconnects page monitoring clusterware with Oracle Enterprise
Manager,
monitoring Oracle Clusterware, interprocess communication (IPC) buffer sizes
adjusting,
IPC protocol,
,
J
Java Database Connectivity (JDBC) clients
Oracle Notification Service usage,
Java-based tools and utilities
CVU,
DBCA,
GSD,
NETCA,
SRVCTL,
JDBC enabling Fast Application Notification events for,
JDBC-thin clients
enabling for Fast Connection Failover (FCF),
job administration
Oracle Enterprise Manager,
K
keystore data security,
KILL SESSION clause
on the ALTER SYSTEM statement,
L
LCK0
Instance Enqueue Process,
level thresholds
LICENSE_MAX_USERS initialization parameter,
List of Cluster Databases page,
listener
listeners
command to remove,
LMD
LMON Global Enqueue Service Monitor,
LMS
Global Enqueue Service Daemon,
Global Cache Service Process,
LMS processes
LMSn processes
load balancing
server-side,
load balancing advisory
load balancing advisory (continued)
configuring your environment for using,
description of,
events and FAN,
Load Balancing Advisory,
local archiving scenario
RMAN,
LOCAL clause
forcing a checkpoint,
local file system
local instance
local node name
LOCAL_NODE parameter
locally managed tablespaces, log files tracing,
LOG_ARCHIVE_FORMAT initialization parameter,
logical transaction ID,
LXTID,
M
maintenance
mass deployment cloning,
media failures recovery from,
Memory Guard,
memory structures in Oracle RAC,
message request counters,
migration
from single-instance,
missing files,
mission critical systems considerations for Oracle RAC, modified data
instance recovery,
monitoring archiver process,
overview and concepts,
performance of global cache block access,
Index-7
monitoring host load average,
mount all non-running instances of an Oracle RAC
multiple cluster interconnects,
multiple databases in a cluster,
multiple instances starting from a single SQL*Plus session,
starting from one node,
multiple public networks,
multitenant container database
mutable functions,
mutables rules for grants,
N
net service name, network
restricting service registration,
Network Attached Storage (NAS),
See also
network resources,
NFS
node server, failure and VIP addresses,
node discovery
Oracle Enterprise Manager Cloud Control,
nodeapps
nodes affinity awareness,
virtual IP addresses,
non-transactional session state,
noncluster databases quiescing,
noncluster Oracle ASM converting to clustered Oracle ASM,
noreplay keyword (terminating or disconnecting
O
objects
creation of and effect on performance,
srvctl object names and abbreviations,
OCI
Index-8
OCI (continued) runtime connection load balancing,
session pools
optimizing,
runtime connection load balancing,
service metrics,
OCRDUMP utility,
ODP.NET
load balancing advisory events,
OLTP environments,
online database relocation relocation feature,
online transaction processing (OLTP)
ons
SRVCTL object name,
ONS
See
Oracle ASM disk group management,
see
Oracle Automatic Storage Management
(Oracle ASM),
Oracle Automatic Storage Management (Oracle ASM) archiving scenario,
converting noncluster Oracle ASM to clustered
Oracle ASM,
installation,
instances
Oracle ASM preferred read failure groups,
preferred mirror read disks,
storage solution,
Oracle Call Interface
See
Oracle Cluster Registry (OCR),
Oracle Clusterware cloning,
control policies
AUTOMATIC,
MANUAL,
using SRVCTL to display and change,
controlling database restarts,
introduction,
introduction and concepts of, managing Oracle processes,
Oracle Database session activity,
Oracle Database QoS Management,
Oracle Database Quality of Service Management
See
Oracle Database QoS Management
Oracle Database Upgrade Assistant,
Oracle Enterprise Manager adding database instances to nodes
Automatic Database Diagnostic Monitor (ADDM),
Average Active Sessions chart,
Cluster Database page,
Cluster Database Performance page performance statistics for an Oracle RAC
configuring to recognize changes in database management,
deleting database instances from nodes,
Global Cache Block Access Latency chart,
job administration,
monitoring load values for available nodes,
Top Activity drill down menu,
using the Interconnects page to monitor Oracle
using to administer Oracle RAC,
using to administer services,
using to back up the server parameter file,
using to convert single-instance databases to
Oracle Real Application Clusters,
using to create DTP services,
using to monitor Oracle Clusterware,
using to monitor Oracle RAC,
using to monitor Oracle RAC environments,
using to restore SPFILE,
using to schedule Automatic Workload
using to set up a fast recovery area,
using to start or stop a database,
using with RMAN,
Oracle Enterprise Manager Cloud Control
Oracle Flex Clusters,
Oracle home
Oracle homes cloning local
shared
Oracle homes (continued) shared (continued)
Oracle Interface Configuration (OIFCFG),
Oracle Managed Files,
Oracle Maximum Availability Architecture (MAA),
Oracle Multitenant,
Oracle Net listeners,
Oracle Net connection failover,
Oracle Net Services
and services,
Oracle Notification Service
SRVCTL object name, used by FAN,
Oracle Notification Services
Oracle processes
managed by Oracle Clusterware,
Oracle RAC adding administrator-managed database
instances, adding policy-managed database instances,
,
adding to nodes in a cluster on Linux and UNIX,
adding to nodes in a cluster on Windows,
administrative privilege
and e-commerce,
background processes
LCK0,
LMD,
LMON,
cloning
converting database from,
converting database to,
converting from non-cluster system,
converting single instance to Oracle RAC One
databases
converting from single-instance Oracle
diagnosing performance problems,
IM column store,
Index-9
Oracle RAC (continued)
overview of administration,
removing on Windows,
removing the software from Linux and UNIX,
security considerations,
shutting down instances,
software components,
storage options
IBM GPFS,
Oracle Automatic Storage Management
(Oracle ASM),
Oracle Automatic Storage Management
Cluster File System (Oracle ACFS),
Oracle OCFS2,
using a fast recovery area in,
Oracle RAC One Node
converting database from,
creating databases,
database services on,
online database relocation,
Oracle Real Application Clusters
Oracle Real Application Clusters One Node
Oracle Resource Manager
Oracle Services using,
Oracle Services for Microsoft Transaction Server
Oracle Streams,
Oracle Streams Advanced Queuing
Oracle Universal Installer database installation,
Oracle Real Application Clusters installation,
Oracle XA,
oradebug ipc command,
OraMTS
external transaction manager,
See also
outages unplanned,
P
parallel processes, parallel recovery
PARALLEL_EXECUTION_MESSAGE_SIZE initialization parameter,
PARALLEL_FORCE_LOCAL initialization parameter,
parallelism in Oracle RAC,
parallel-aware query optimization, parameter file
parameter file search order, parameters
that must be identical on all instances,
that must be unique on all instances,
password file-based authentication,
PDBs
performance aggregates by services,
monitoring activity by wait events, services, and instances,
monitoring database throughput,
monitoring global cache block access,
monitoring potential problems in the database,
primary components affecting,
service aggregates by instances,
using ADDM,
performance evaluation overview and concepts, performance statistics,
PFILE
phases
planned maintenance
using Application Continuity,
pluggable database
See
PMON background process,
policy set,
policy-managed database,
policy-managed database instances adding,
policy-managed databases
Index-10
policy-managed databases (continued) deleting on Linux and UNIX,
deploying,
managing,
PREFERRED instances for services,
preferred read disks
Oracle ASM in an Oracle RAC extended distance cluster,
private interconnect determining usage,
private network alternative interconnect,
private network IP address,
processes managed by Oracle Clusterware,
parallel,
public and private interfaces
shown in Oracle Enterprise Manager,
public network
Q
query optimizer default cost model for,
queue tables,
quiesce database
in Oracle Real Application Clusters,
quiesced databases,
quiescing noncluster database,
R
rebalancing
RECOVER command
SQL*Plus,
recovery
from multiple node failure,
from single-node failure,
instance,
parallel,
RECOVERY_PARALLELISM parameter,
redo log files
using,
redo log groups,
redo logs
format and destination specifications,
redo thread,
reducing contention,
remote Oracle Notification Service subscription,
Remote Slave Monitor (RSMN),
REMOTE_LOGIN_PASSWORDFILE initialization parameter,
replicated databases and global services,
resource contention, resource manager, resource profiles
resources
resources held by the session,
restore scenarios
RMAN,
restore scheme
result cache
enabling,
RESULT_CACHE_MAX_SIZE initialization parameter,
,
RMAN
configuring channels,
configuring channels to use automatic load
configuring one channel for each instance, configuring snapshot control file locations,
crosschecking on multiple nodes,
restore scenarios,
using to create SPFILE backups,
RMSn
Oracle RAC management processes,
rolling back
instance recovery,
root.sh script
$ORACLE_HOME,
RSMN
runtime connection load balancing defined,
Runtime Connection Load Balancing,
S
scalability
Oracle RAC,
Index-11
scan
SCAN listener
and restricting service registration,
scan_listener
scripts
$ORACLE_HOME/root.sh, security
keystore,
sequence-based indexes, sequences
Server Control Utility
Server Management
server parameter file
server parameter files creating,
server pool,
server pools creating for a policy-managed database,
servers
relocating from another server pool,
service
service level objective
defining for Oracle RAC,
service levels, service metrics
OCI runtime connection load balancing,
runtime connection load balancing,
SERVICE TIME
SERVICE_NAMES initialization parameter
services
activity levels aggregated by instances,
activity levels aggregated by services,
activity levels aggregated by waits,
administering,
administering with Oracle Enterprise Manager,
administering with SRVCTL,
,
attributes edition,
buffer cache access,
configuring automatic workload management
Index-12
services (continued) default,
dependencies,
enabling event notification,
level thresholds,
management policy automatic,
managing after planned maintenance,
managing on PDBs,
relocating,
,
relocating after planned maintenance,
restricting registration with listeners,
specifying a service,
starting after planned maintenance,
stopping after planned maintenance,
services for administrator-managed databases, session state consistency
sessions
terminating on a specific instance, setting instances,
,
shared everything,
SHOW INSTANCE command
SHOW PARAMETER command
SHOW SGA command
,
SHUTDOWN command
SHUTDOWN IMMEDIATE, instances, shutting down an instance
SHUTDOWN TRANSACTIONAL, shutting down
abnormal shutdown,
sidalrt.log file,
single client access name
See
Single Client Access Name (SCAN)
SRVCTL object name,
single-instance database convert to Oracle RAC database
administrative considerations,
single-instance databases
converting to Oracle RAC database,
SMON process
recovery after SHUTDOWN ABORT, snapshot control file
speed-up for data warehouse systems,
SPFILE
backups
creating,
recovering,
restore with Oracle Enterprise Manager,
restore with RMAN,
SPFILE initialization parameter,
,
SQL statements
instance-specific,
SQL*Plus commands
effect on instances,
SRVCTL administering Oracle ASM instances,
cluster database configuration tasks,
command feedback,
commands
-eval parameter,
add database,
add network,
add scan,
add scan_listener,
add service,
add srvpool,
config database,
SRVCTL (continued) commands (continued)
config ons, config scan,
config scan_listener,
disable database,
disable diskgroup,
disable nodeapps,
disable ons,
disable service, disable vip,
enable listener,
enable scan,
enable scan_listener, enable service,
enable volume,
getenv listener,
help,
modify database, modify instance,
modify nodeapps,
modify ons,
modify service,
modify vip,
predict database,
predict diskgroup,
predict service,
Index-13
SRVCTL (continued) commands (continued)
relocate server,
relocate vip,
remove database,
remove network,
remove nodeapps,
remove scan,
remove service,
remove srvpool,
remove vip,
remove volume,
setenv listener,
srvctl setenv,
start diskgroup,
start instance,
start listener,
start ons,
start scan_listener,
status database,
status home,
status nodeapps,
status scan,
status service,
status srvpool,
status vip,
status volume,
stop diskgroup,
stop instance,
stop listener,
Index-14
SRVCTL (continued) commands (continued) stop nodeapps,
stop service, stop vip,
stop volume,
unsetenv database,
unsetenv nodeapps,
update gns,
update instance,
update listener,
update scan_listener, upgrade database,
deprecated commands and options,
deprecated commands and parameters,
difference between SRVCTL and
CRSCTL,
enabling event notification, getenv, usage description,
modify, usage description,
object name
database,
Oracle Notification Service,
service, vip,
overview and concepts,
predict, usage description,
relocate, usage description,
setenv, usage description,
single-character parameters,
specifying a continuation of command line entries,
start,
stop or start cluster database,
stop, usage description,
SRVCTL (continued)
SRVM_TRACE environment variable,
Standard Edition installing Oracle ASM,
starting administrator-managed databases,
starting policy-managed databases,
STARTUP command
SQL*Plus,
static session state consistency,
statistics
Statspack
storage
administering in Oracle RAC,
Oracle Automatic Storage Management (Oracle
ASM),
subnet configuring for virtual IP address,
subnets,
SYSASM privilege,
SYSAUX tablespace
increasing size when adding nodes,
reducing size when removing nodes,
SYSOPER,
SYSRAC connections to an Oracle ASM instance,
System Global Area (SGA) size requirements,
T
tablespaces automatic segment space management (ASSM) in
automatic undo management in Oracle RAC,
TCP network ports
Windows Firewall considerations,
TCP/IP,
terminating a session on a specific instance,
THREAD initialization parameter,
threads
Top Activity drill down menu on the Cluster Database Performance page,
Top Cluster Events, ASH report,
Top Remote Instance,
Top Remote Instance, ASH report,
trace files
sidalrt.log,
trace files for background processes,
TRACE_ENABLED initialization parameter, tracing
enabling Java-based tools and utilities,
SRVM_TRACE environment variable,
writing to log files, transaction failover,
Transaction Guard
configuring JDBC-thin clients,
configuring OCI clients,
configuring service attributes,
transactional TAF,
transactions distributed SQL,
DTP/XA,
instance failure,
waiting for recovery,
transparent application failover (TAF) and services,
Transparent Data Encryption specifying the
ENCRYPTION_WALLET_LOCATION parameter,
with encrypted keystores and obfuscated keystores,
tuning
using ADDM,
U
UNDO_MANAGEMENT initialization parameter,
UNDO_RETENTION initialization parameter,
UNDO_TABLESPACE parameter,
upgrades
changing management policy for,
V
V$,
Index-15
vendor clusterware,
verification data files, online files,
versions compatibility for Oracle RAC and Oracle Database software,
views
creating for Oracle Real Application Clusters,
dynamic performance
GV$,
instance-specific
V$ views,
VIP
VIPs
node,
Virtual Internet Protocol (VIP) address,
virtual IP address
VNCR
See
W
wait events
aggregated for service performance,
block-related,
contention-related, load-related,
message-related,
Windows Firewall, and services,
workload management
See
workloads
See Also
automatic workload management,
X
XA transactions spanning Oracle RAC instances,
using services with,
XA Transactions,
Index-16
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