Chapter 2. Dynamic resource definition. IBM Version 11 System Definition

Chapter 2. Dynamic resource definition

You can create, update, or delete certain IMS runtime resource definitions

(database, application program, Fast Path routing code, and transaction) and add them to your IMS dynamically, thereby eliminating the need to use the batch system definition or online change processes. This process is called the dynamic resource definition (DRD) process.

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Overview of dynamic resource definition

With dynamic resource definition (DRD), you can use type-2 commands to define resources such as application programs, databases, routing codes, and transactions, along with resource descriptors.

For IMS systems in which DRD is not enabled or unavailable, you must use the

APPLCTN, DATABASE, RTCODE, and TRANSACT macros, along with the batch system definition process, to create the resource definitions for these resources and store them in the IMS.MODBLKS data set. The following figure shows the control block generation process:

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Figure 4. Control block generation process

With DRD enabled, the APPLCTN, DATABASE, RTCODE, and TRANSACT macros are optional. If you do not code these macros as part of the system definition process, you can either import resource definitions into IMS from a resource definition data set (RDDS), or you can use type-2 commands to define resources to

IMS dynamically (instead of using online change).

For IMS systems in which DRD is not enabled or unavailable, after IMS initialization, you use the online change process to add, change, and delete resource definitions dynamically. The online change process requires that you:

1.

Generate the resource definitions and store them in an IMS.MODBLKS staging library data set

2.

Run the Online Change Copy utility (DFSUOCU0) to copy the staging library into an inactive library

3.

Run a series of online change commands to cause the change to take effect (see the figure below)

© Copyright IBM Corp. 1974, 2014

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Figure 5. Online change process for IMS resources

Another aspect of the online change process is that, during the COMMIT phase, all the resources associated with the definitions in the IMS.MODBLKS data set are quiesced, which affects IMS availability.

Recommendation:

Unless you have a simple system, and online change meets your requirements, use DRD with RDDSs rather than the IMS.MODBLKS data set.

To change some resources online (for example, resources in IMS.ACBLIB), you cannot use DRD and must use the online change process.

Related concepts

:

Modifying system resources online (Operations and Automation)

Managing resource and descriptor definitions

With dynamic resource definition (DRD) enabled, you can perform several tasks to manage the resource and descriptor definitions for your IMS system.

With DRD enabled, you can perform the following tasks from a single point of control (SPOC) application, which can be the IMS Control Center, TSO SPOC, vendor-supplied software, or an application program that you write: v

Create resources or descriptors v

Update resources or descriptors v Delete resources or descriptors v

Query definitional attributes of resources or descriptors (using the QUERY command) v

Export resource and descriptor definitions from IMS to a resource definition data set (RDDS) v

Import resource and descriptor definitions from an RDDS into IMS, which creates resources at IMS initialization without using the system definition process

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With DRD, you can use the CREATE, IMPORT, UPDATE, and DELETE type-2 commands to dynamically create, update, and delete application program, database, routing code, and transaction resource and descriptor definitions. Issue the commands from a single point of control (SPOC) application (for example, the

TSO SPOC shipped with IMS). You can also use the IMS Manage Resources application that is available from the IMS Application Menu (option 2).

Resource descriptors are templates that can be used to define new resources and descriptors. IMS supplies four resource descriptors, one for each resource type. The descriptors contain IMS-system default values for each resource attribute. These

IMS-supplied descriptors cannot be deleted or modified. IMS-supplied descriptors are not exported to RDDS. The four IMS-supplied resource descriptors are: v

DFSDSDB1 (database descriptor) v

DFSDSPG1 (application program descriptor) v

DBFDSRT1 (Fast Path routing code descriptor) v

DFSDSTR1 (transaction descriptor)

You can use the IMS-supplied descriptors as models for creating resources or additional descriptors. You can also create descriptors without modeling them after existing descriptors. Initially, the IMS-supplied descriptors are set as the default descriptors, but you can designate one of your own descriptors as the default by using the DEFAULT(Y) keyword on the CREATE or UPDATE command.

When you create a resource without specifying a model (that is, you do not specify the LIKE keyword), any attribute values that are not specified on the CREATE command are inherited from the default descriptor. When you create a resource that is modeled from a descriptor (using the LIKE keyword), any attribute values that are not specified on the CREATE command are inherited from the descriptor.

Similarly, when you create a resource using an existing resource as a model (using the LIKE keyword), any attribute values that are not specified on the CREATE command are inherited from the existing resource.

Tip:

To ease the transition from using the online change process to using DRD, you can create runtime resource definitions using the batch system definition process and then enable DRD so that you can use the DRD commands.

IMS systems can export resources that are defined by the batch system definition process and resource definitions that have been created or updated dynamically, to an RDDS, using the EXPORT DEFN TARGET(RDDS) command or by setting up your system for automatic export.

These resource definitions can then be imported from the RDDS into an IMS system during cold start processing. To ensure that your changes are recovered across a cold start, set up your system to automatically export your resource and descriptor definitions at checkpoint time and to automatically import the definitions from the RDDS during cold start processing.

In situations when IMS receives a message for an unknown destination, you can also use the Destination Creation exit routine (DFSINSX0) to define a new transaction to IMS for that message and, if necessary, define the application program that is associated with the transaction.

Chapter 2. Dynamic resource definition

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Attention:

DRD changes are not necessarily made across all IMS systems in an

IMSplex. Changes might be successful on some IMS systems but fail on others. You must verify that changes have been made across all systems.

The figure that follows shows the ISPF panel for managing resources.

Help

------------------------------------------------------------------------------

SPOC IMS Manage Resources

Command ===>

Select an action and press Enter.

* Action . . . . . .

1. Create new resources

2. Delete resources

3. Query resources

4. Update resources

5. Import resources

6. Export resources

7. Manage RDDS

Figure 6. IMS Manage Resources main panel

Commands that support dynamic resource definition

With dynamic resource definition (DRD), you can use type-1 and type-2 commands to define resource and descriptor definitions.

The following IMS type-2 commands support DRD.

CREATE DB

CREATE DBDESC

CREATE PGM

CREATE PGMDESC

CREATE RTC

CREATE RTCDESC

CREATE TRAN

CREATE TRANDESC

DELETE DB

DELETE DBDESC

DELETE PGM

DELETE PGMDESC

DELETE RTC

DELETE RTCDESC

DELETE TRAN

DELETE TRANDESC

EXPORT DEFN

IMPORT DEFN

QUERY DB

QUERY DBDESC

QUERY PGM

QUERY PGMDESC

QUERY RTC

QUERY RTCDESC

QUERY TRAN

QUERY TRANDESC

UPDATE DB

UPDATE DBDESC

UPDATE PGM

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System Definition

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UPDATE PGMDESC

UPDATE RTC

UPDATE RTCDESC

UPDATE TRAN

UPDATE TRANDESC

The following IMS type-1 commands support DRD: v

/CHECKPOINT

If automatic export is enabled, and one or more resource or descriptor definitions have been created, updated, or deleted since the last checkpoint, the

/CHECKPOINT command causes all resource and descriptor definitions to be written to the system RDDS that contains the oldest data.

v

/CHECKPOINT DUMPQ|FREEZE|PURGE

If automatic export is enabled, and one or more resource or descriptor definitions have been created, updated, or deleted since the last checkpoint, the

/CHECKPOINT DUMPQ|FREEZE|PURGE command causes all resource and descriptor definitions to be written to the system RDDS that contains the oldest data.

v /MODIFY

If DRD is enabled and MODBLKS is specified on the /MODIFY command, the command fails.

The X'22' log record represents an action generated by a type-2 command. It is written for most type-2 commands that are recoverable and for some type-2 commands, such as QUEUE and UPDATE, for diagnostic information. Refer to

DFSLOG22 for mapping of the X'22' log record. For most commands, the X'22' log records indicate that the type-2 command is recoverable, and it is used to reprocess the command during a warm or emergency restart. The X'22' log record is also used to communicate the command changes to the XRF alternate system, the

DBCTL warm standby system, or the FDBR system. For some commands, the X'22' log records are for diagnostics only and are not used to recover or reprocess the command.

For the transaction, program, routing code, and database resources and descriptors, the X'22' log record tracks the changes made to the runtime resource and descriptor definitions that result from the CREATE, UPDATE, DELETE, and

IMPORT commands, and the MODBLKS online change procedure.

The EXPORT command does not generate an X'22' log record.

In addition to being able to dynamically create, update, query, and delete runtime resource and descriptor definitions, with DRD you have other benefits, including: v

Type-2 command benefits, including the ability to sort, scroll, and use wildcards in the command.

v

Returned command completion code text is displayed with a brief description of the completion code.

v All create, update, and delete activities are logged in the log record X'22', to aid in recovery after a warm or emergency restart.

v

Create, update, access time stamps are maintained.

If DRD is not enabled, you can use the following type-2 commands: v

QUERY DB v

QUERY PGM

Chapter 2. Dynamic resource definition

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QUERY RTC v

QUERY TRAN v

UPDATE DB START() v

UPDATE DB STOP() v

UPDATE PGM START() v

UPDATE PGM STOP() v UPDATE RTC START() v

UPDATE RTC STOP() v UPDATE TRAN SET(LOCK()) v

UPDATE TRAN START() v

UPDATE TRAN STOP()

The EXPORT command can be issued in a non-DRD enabled IMS system.

However, in a non-DRD enabled IMS system, the only RDDS that can be exported to is a non-system RDDS.

Dynamic resource definition and system definition

Specify parameters related to dynamic resource definition (DRD) in the DFSDFxxx member of the IMS PROCLIB data set.

The DFSDFxxx member of the IMS PROCLIB data set contains parameters for the

IMS Common Service Layer (CSL), shared queues, databases, restart exit routines, dynamic resource definition (DRD), the Fast Path 64-bit buffer manager, and the

IMS abend search and notification procedure.

The DFSDFxxx member includes some parameters that also exist in the DFSSQxxx member (for defining parameters related to shared queues) and the DFSCGxxx member (for defining parameters related to the CSL). If you specify these common parameters in the DFSDFxxx member, you do not have to specify them in the

DFSSQxxx and DFSCGxxx members. Any attributes explicitly defined in the

DFSSQxxx and DFSCGxxx members override the attributes defined in the

DFSDFxxx member.

The MODBLKS= keyword enables either DRD (MODBLKS=DYN) or the online change process (MODBLKS=OLC). The MODBLKS= keyword can only be changed as part of a cold start. MODBLKS=OLC and MODBLKS=DYN are mutually exclusive. You can specify the MODBLKS= keyword in either the DFSCGxxx member, or in the CSL section of the DFSDFxxx member. If you specify a value for the MODBLKS= keyword in the DFSCGxxx member, that value overrides the value specified for the MODBLKS= keyword in the DFSDFxxx member.

If the online change process is disabled (DRD is enabled), the IMS, DBC, and DCC procedures no longer require the DD statements for the IMS.MODBLKS data sets,

IMS.MODBLKSA and IMS.MODBLKSB.

Recovery of changed runtime resource and descriptor definitions

Changes that are made to resource and descriptor definitions by using type-2 commands are logged and recoverable across a warm or emergency restart.

The runtime resource and descriptor definitions are restored from the logs during restart processing.

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System Definition

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For changes to be recoverable across a cold start, the changed resource and descriptor definitions must be exported to, or stored in, a resource definition data set (RDDS) before IMS terminates, and imported into IMS either: v

During cold start with the automatic import function.

v

After IMS is up and running with the IMPORT command.

You can alternatively perform the following tasks:

1.

Update your IMS system definition macros

2.

Perform a system generation

3.

Cold start IMS

4.

Import the resource definitions from the IMS.MODBLKS data set

The external data source in which resource and descriptor definitions are stored is a BSAM data set called a

resource definition data set

(RDDS). The definitions in an

RDDS are in a binary format. RDDSs are not supported in IMS FDBR regions or on

IMS RSR tracking systems.

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Requirements for dynamic resource definition

To use dynamic resource definition (DRD), you must define a Common Service

Layer (CSL) with at least Structured Call Interface (SCI) and Operations Manager

(OM). You must also ensure that your system has a type-2 command interface.

It is also suggested that you define one or more resource definition data sets

(RDDSs) in which to save your current resource definitions.

DRD requires: v

A CSL that contains SCI and OM.

v

One or more RDDSs.

v

A type-2 command interface such as the TSO SPOC, IMS Control Center, or other OM interface, for DRD commands.

The INITMOD procedure requires that you define either MODBLKSA or

MODBLKSB to initialize the MODSTAT data set, even for an IMS that does not define the MODBLKS data set.

In a DRD environment, the MODBLKS staging, active, and inactive data sets are no longer required. However, the Global Online Change utility (DFSUOLC0) requires that you define either MDBS=A or MDBS=B to initialize the OLCSTAT data set, even for an IMS that does not define the MODBLKS data set.

Restrictions for dynamic resource definition

If you plan to use dynamic resource definition (DRD) in your IMS system, be aware that several restrictions apply to your use of DRD.

The following restrictions apply to DRD: v

When DRD is enabled, you cannot perform online change for the resources that are typically defined in the IMS.MODBLKS data set. If you have a simple system, such as a single IMS, and online change meets your requirements, consider continuing to use online change and not enabling DRD.

v

In an IMSplex with only one IMS and DRD enabled, the /MODIFY PREPARE

MODBLKS and INITIATE OLC PHASE(PREPARE) TYPE(MODBLKS) commands

Chapter 2. Dynamic resource definition

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PHASE(PREPARE) ALL do not apply to the IMS.MODBLKS data set.

v

When DRD is disabled, CREATE, DELETE, IMPORT, and most UPDATE commands that change the definitional attributes of a resource are rejected. The following parameters for the UPDATE TRAN command are permitted whether or not DRD is enabled:

– CLASS(class)

– CPRI(value)

– LCT(value)

– LPRI(value)

– MAXRGN(number)

– MSNAME(name)

– NPRI(value)

– PARLIM(value)

– PLCT(value)

– SEGNO(number)

– SEGSZ(size)

– TRANSTAT(Y | N) v

You cannot delete an IMS-supplied descriptor. The only attribute you can update on an IMS-supplied descriptor is the DEFAULT attribute.

v Because of the default Operations Manager (OM) routing in a sysplex, DRD commands are routed to all the IMS systems, unless you specify otherwise.

However, the commands are not coordinated across the sysplex, so a command can succeed on some IMS systems and fail on others.

v

The Multiple Systems Verification utility (DFSUMSV0) can verify resources defined only by the batch system definition process; it cannot verify resources that were created using DRD. Use the /MSVERIFY command to verify resources that are created dynamically.

v

You can update a resource or a descriptor definition, but the changes to that resource or descriptor definition are not propagated to the resource or descriptor definitions that were built from the updated resource or descriptor definition.

v You can import a resource or descriptor from a resource definition data set

(RDDS) and it affects any resource or descriptor explicitly specified in the

IMPORT DEFN command, but it does not affect any resources or descriptors built from the specified resource or descriptor.

v

DRD commands can be issued only through the OM API.

v

DRD commands that work on database resources and descriptors cannot be issued in a DCCTL environment.

v

DRD commands that work on transactions and routing code resources and descriptors cannot be issued in a DBCTL environment.

v

None of the commands that support DRD can be issued on XRF alternate or

RSR tracker systems, or FDBR regions.

v DELETE DB and UPDATE DB commands are rejected for MSDBs.

Related reference

:

IMS commands (Commands)

Chapter 17, “Members of the IMS PROCLIB data set,” on page 589

Considerations for using dynamic resource definition

To ensure that your use of dynamic resource definition (DRD) is successful, be aware of these usage considerations.

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In addition to the requirements and restrictions that are associated with using

DRD, consider the following issues: v

Before enabling dynamic resource definition or shared queues, evaluate any existing DFSINSX0 exit routines. The DFSINSX0 exit might need to be changed so that it checks whether LTERM creation is allowed before it accesses the

USEQDATA parameter list that is related to LTERM processing. If LTERM creation is not allowed, the USEQDATA buffer address (INSXAUSQ) is zero.

v In an IMSplex with multiple IMS systems, some having DRD enabled, the command INITIATE OLC PHASE(PREPARE) TYPE(MODBLKS) is allowed so that the IMS systems that do not have DRD enabled can perform online change processes.

v

The online change process is enabled and DRD is not enabled when:

– MODBLKS=OLC is specified in the DFSCGxxx member of the IMS PROCLIB data set

– MODBLKS=OLC is specified in the COMMON_SERVICE_LAYER section of the DFSDFxxx member of the IMS PROCLIB data set

– A value is not specified for the MODBLKS= keyword in either member.

v

In a shared EMH queues environment, a CREATE PGM command creates the application program, even if there are messages on the shared EMH queues for the application program. If the messages are placed on the shared EMH queues because the program was defined as Fast Path on another IMS, but this program is being created as non-Fast-Path on this IMS, this IMS is unable to access the messages on the shared EMH queues.

v

All the DRD commands that work on application program resources and descriptors can be issued in DB/DC, DBCTL, and DCCTL environments.

v

The MODBLKS DD statement is not required for MODBLKS=OLC or

MODBLKS=DRD in an FDBR system.

v

If you are not running with DRD enabled, any changes you make to the

MODBLKS resources (database, transactions, programs, and routing codes) by using the type-1 commands persist across a warm or emergency restart, but they do not persist across a cold start. In a non-DRD environment, the control blocks that are used to manage the resources (DDIRs, PDIRs, SMBs, and RCTEs) are loaded from the MODBLKS data set at cold start. If a type-1 command is issued to change the attribute of a resource (such as the database access type or the transaction class), the internal control blocks are updated and the changes are recovered across a warm or emergency restart. If you perform a cold start, however, the control blocks are reloaded from the MODBLKS data set, and, unless you have updated your MODBLKS data set, the updated attributes revert to the original values.

If you are running with DRD enabled, any changes you make by using the type-1 or type-2 commands persist across a warm or emergency restart. They also persist across a cold start if the updated resource definitions are exported to an RDDS and then imported from the RDDS during cold start. When you export the resource definitions to an RDDS, you export all the current attribute values.

If you have changed the value of one of the attributes by using a type-1 or type-2 command (such as the database access type or the transaction class), the updated attribute is exported. The updated attribute values are then imported during cold start if you have automatic import enabled.

v

During a cold start, the partition status or access state is copied from the

HALDB master. If you export the HALDB master status to the RDDS, the status of the master and its partitions is obtained from the RDDS.

Chapter 2. Dynamic resource definition

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Enabling dynamic resource definition

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Before you can add, change, or delete IMS resources dynamically, you must first enable the dynamic resource definition (DRD) function.

The following procedure must be performed before enabling IMS to use DRD with a resource definition data set (RDDS):

1.

Verify DRD is not yet enabled, meaning either: v The MODBLKS keyword is not specified anywhere.

v

The MODBLKS=OLC keyword is specified in either the DFSCGxxx member or the COMMON_SERVICE_LAYER section of the DFSDFxxx member of the

IMS PROCLIB data set.

2.

Verify that IMS is stabilized in your test environment and the IMS.MODBLKS

data set is complete and working properly.

3.

Verify that the IMS in which you are enabling DRD has a Common Service

Layer (CSL) defined. Specify the CSL parameters in either: v

The COMMON_SERVICE_LAYER section of the DFSDFxxx member in the

IMS PROCLIB data set v The DFSCGxxx member in the IMS PROCLIB data set

If you specify values in both the COMMON_SERVICE_LAYER section of the

DFSDFxxx member and in the DFSCGxxx member, the CSL values in the

DFSCGxxx member override the values in the COMMON_SERVICE_LAYER section of the DFSDFxxx member.

4.

Verify that your in-house procedures that use the online change process for the resources defined in the IMS.MODBLKS data set have been copied and stored, and you have replacement procedures that use DRD commands.

Related reference

:

“COMMON_SERVICE_LAYER section of the DFSDFxxx member” on page 674

“DFSCGxxx member of the IMS PROCLIB data set” on page 651

Enabling IMS to use dynamic resource definition with a resource definition data set

After performing the initial verification of your IMS environment, you can enable

IMS to use dynamic resource definition (DRD) with a resource definition data set

(RDDS).

To enable IMS to use dynamic resource definition (DRD) with a resource definition data set (RDDS):

1.

Shut down IMS normally.

2.

Change MODBLKS=OLC to MODBLKS=DYN in either the

COMMON_SERVICE_LAYER section of the DFSDFxxx member or in the

DFSCGxxx member in the IMS PROCLIB data set.

3.

Specify the following keywords in the DYNAMIC_RESOURCES section of the

DFSDFxxx member of the IMS PROCLIB data set: v

AUTOEXPORT=AUTO or AUTOEXPORT=RDDS v

AUTOIMPORT=AUTO or AUTOIMPORT=RDDS v

RDDSDSN=(

rdds1,rdds2,rdds3

)

4.

Use either the IEBGENER program or the ALLOCATE function of ISPF utilities to allocate the RDDS data sets.

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5.

Cold start IMS, specifying DFSDF=

xxx

in the control region execution parameters, where

xxx

identifies the suffix of the DFSDF

xxx

member in the IMS

PROCLIB data set that IMS uses for this startup. IMS loads the resource definitions from the IMS.MODBLKS data set because the defined RDDSs are empty. The IMS.MODBLKS data set is used only the first time you implement

DRD, except for fallback purposes. IMS uses the resource definitions to create the internal control blocks required to manage the resources. When the initial checkpoint is taken, the resource definitions are automatically written out to one of the defined RDDSs because AUTOEXPORT=AUTO is specified. Also, because AUTOIMPORT=AUTO is specified and the RDDSs are no longer empty, IMS loads its resource and descriptor definitions from the RDDS with the most current data the next time that IMS coldstarts.

Restriction:

After IMS starts with DRD enabled, you can no longer use the online change process to add, change, or delete database, application program, route code, or transaction resource definitions.

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Creating runtime resource and descriptor definitions

When dynamic resource definition (DRD) is enabled, you can define runtime resources and descriptor definitions to IMS dynamically, eliminating the requirement to use the online change process or to cold start IMS.

When a resource or descriptor is defined to IMS, IMS stores information about the resource or descriptor, such as the attributes and the status, in control blocks. The information that is kept in the control blocks is referred to as the runtime resource or descriptor definition. Although the overall process for creating runtime database, application program, transaction, and routing code definitions is the same, there are minor variations in the steps you perform.

When DRD is enabled, runtime resources can be created by: v

Importing the stored resource definitions from the IMS.MODBLKS data set during an IMS cold start.

v

Importing the stored resource definitions from the resource definition data set

(RDDS) with the automatic import function or the IMPORT DEFN

SOURCE(RDDS) command.

v

Using the appropriate CREATE command (according to the type of resource definition you want to create).

When DRD is enabled, runtime descriptor definitions can be created by: v

Importing the stored descriptor definitions from the RDDS with the automatic import function or the IMPORT DEFN SOURCE(RDDS) command.

v

Using the appropriate CREATE command (according to the type of descriptor definition you want to create).

The resource and descriptor definitions that you create dynamically using either the CREATE command or the IMPORT DEFN command exist only during the current execution of the IMS system, and they are recoverable across a warm or emergency restart.

To preserve the resource and descriptor definitions across a cold start, export the definitions to an RDDS before IMS terminates, and then import the stored definitions from the RDDS back into IMS either during cold start processing using the automatic import function, or when IMS is up and running using the IMPORT

DEFN command.

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Each resource or descriptor definition can be created individually, unlike the online change process where either all resource definitions must be created or no resource definitions are created.

Creating runtime database resource and descriptor definitions with the CREATE command

With dynamic resource definition (DRD) enabled, you can create runtime resources and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

Create runtime database resource and descriptor definitions using the CREATE DB and CREATE DBDESC commands.

1.

Optional: Issue a QUERY DBDESC DEFAULT(Y) SHOW (ALL) command to view the current database default settings and evaluate whether they meet your requirements for the new database resource or descriptor definition. If the default settings do not meet your requirements, you have the following options: v

Override the default settings by issuing the CREATE command with parameter values that meet your requirements.

v Create the resource or descriptor definition based on an existing resource or descriptor definition by using either the LIKE (RSC(

resource_name

)) keyword or the LIKE (DESC(

descriptor_name

)) keyword on the CREATE command.

v

Create a default descriptor by issuing a CREATE DBDESC NAME() SET

(DEFAULT(Y)) command with the settings that meet your requirements.

The next two steps can be performed in any order.

2.

Issue a CREATE DB or CREATE DBDESC command to create a database resource definition or database descriptor definition, respectively.

3.

Define the database, as well as its relationships to other resources, by running the Database Description Generation (DBDGEN) utility.

After dynamically defining a database resource, before it can be used, a database management block (DMB) must reside in the IMS.ACBLIB data set. If the database that was dynamically defined is a main storage database (MSDB): v

The database segments must be in the MSDBINIT data set.

v

The MSDBs must be defined in the DBFMSDBx procedure.

v

The DBFMSDBx procedure must be in the IMS.PROCLIB data set.

For information about the CREATE command, see

IMS Version 11 Commands,

Volume 1: IMS Commands A-M

.

For information about loading MSDB segments into the MSDBINIT data set, see

MSDB Maintenance utility (DBFDBMA0) (Database Utilities).

For information about the DBFMSDBx procedure, see “DBFMSDBx member of the

IMS PROCLIB data set” on page 647.

For general information about MSDBs, see

IMS Version 11 Database Administration

.

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Creating runtime application program resource and descriptor definitions with the CREATE command

With dynamic resource definition (DRD) enabled, you can create runtime application program resources and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

Create runtime application program resource and descriptor definitions using the

CREATE PGM and CREATE PGMDESC commands.

1.

Optional: Issue a QUERY PGMDESC DEFAULT(Y) SHOW (ALL) command to view the current application program default settings and evaluate whether they meet your requirements for the new application program resource or descriptor definition. If the default settings do not meet your requirements, you have the following options: v

Override the default settings by issuing the CREATE command with parameter values that meet your requirements.

v

Create the resource or descriptor definition based on an existing resource or descriptor definition by using either the LIKE (RSC(

resource_name

)) keyword or the LIKE (DESC(

descriptor_name

)) keyword.

v

Create a default descriptor by issuing a CREATE PGMDESC NAME() SET

(DEFAULT(Y)) command with the settings that meet your requirements.

The next two steps can be performed in any order.

2.

Issue a CREATE PGM or CREATE PGMDESC command to create application program resources or descriptors definitions, respectively.

3.

Define the application program, as well as its relationships to other resources, by running the Program Specification Block Generation (PSBGEN) utility.

For the details about parameters for the CREATE command, see

IMS Version 11

Commands, Volume 1: IMS Commands A-M

.

Creating runtime Fast Path routing code resource and descriptor definitions with the CREATE command

With dynamic resource definition (DRD) enabled, you can create runtime resources and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

Create runtime Fast Path routing code resources and descriptor definitions using the CREATE RTC and CREATE RTCDESC commands.

1.

Optional: Issue a QUERY RTCDESC DEFAULT(Y) SHOW (ALL) command to view the current Fast Path routing code default settings and evaluate whether they meet your requirements for the new Fast Path routing code resource or descriptor definition. If the default settings do not meet your requirements, you have the following options: v

Override the default settings by issuing the CREATE command with parameter values that meet your requirements.

v

Create the resource or descriptor definition based on an existing resource or descriptor definition by using either the LIKE (RSC(

resource_name

)) keyword or the LIKE (DESC(

descriptor_name

)) keyword v

Create a default descriptor by issuing a CREATE RTCDESC NAME() SET

(DEFAULT(Y)) command with the settings that meet your requirements.

Chapter 2. Dynamic resource definition

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2.

Issue a CREATE RTC to create Fast Path routing code resources or a CREATE

RTCDESC command to create Fast Path routing code descriptor definitions.

For the details about parameters for the CREATE command, see

IMS Version 11

Commands, Volume 1: IMS Commands A-M

.

Creating runtime transaction resource and descriptor definitions with the CREATE command

With dynamic resource definition (DRD) enabled, you can create runtime resources and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

Create runtime transaction resource and descriptor definitions using the CREATE

TRAN and CREATE TRANDESC commands.

In addition to using the CREATE TRAN command to create transaction resources, you can use the Destination Creation exit routine (DFSINSX0).

To create runtime transaction resource and descriptor definitions using the

CREATE TRAN and CREATE TRANDESC commands, perform the following procedure:

1.

Optional: Issue a QUERY TRANDESC DEFAULT(Y) SHOW (ALL) command to view the current transaction default settings and evaluate whether they meet your requirements for the new transaction resource or descriptor definition. If the default settings do not meet your requirements, you have the following options: v

Override the default settings by issuing the CREATE command with parameter values that meet your requirements.

v

Create the resource or descriptor definitions based on an existing resource or descriptor definition by using either the LIKE (RSC(

resource_name

)) keyword or the LIKE (DESC(

descriptor_name

)) keyword.

v Create a default descriptor by issuing a CREATE TRANDESC NAME() SET

(DEFAULT(Y)) command with the settings that meet your requirements.

2.

Issue a CREATE TRAN or CREATE TRANDESC command to create transaction resources or descriptor definitions, respectively.

For the details about parameters for the CREATE command, see

IMS Version 11

Commands, Volume 1: IMS Commands A-M

.

Creating runtime resource and descriptor definitions in an

IMSplex with the CREATE command

If you have a mixture of DRD-enabled and DRD-disabled IMS systems in an

IMSplex, you can create resource or descriptor definitions for this environment.

Perform the following procedure:

1.

Perform an online change process for the IMS.MODBLKS data set on the IMS systems that have not migrated to DRD.

2.

Issue CREATE commands for the resource or descriptor definitions you want to create on the IMS systems that have DRD enabled.

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System Definition

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Updating runtime resource and descriptor definitions

When dynamic resource definition (DRD) is enabled, you can update runtime resource and descriptor definitions dynamically, eliminating the need to use the online change process or to cold start IMS. Although the overall process for updating runtime database, application program, transaction, and routing code definitions is the same, there are minor variations in the steps you perform.

When DRD is enabled, runtime resources can be updated by: v Importing the stored resource definitions from the resource definition data set

(RDDS) by using the IMPORT DEFN SOURCE(RDDS) command.

v

Using the appropriate UPDATE command (according to the type of resource definition you want to update).

When DRD is enabled, runtime descriptor definitions can be updated by: v

Importing the stored descriptor definitions from the RDDS by using the

IMPORT DEFN SOURCE(RDDS) command.

v

Using the appropriate UPDATE command (according to the type of descriptor definition you want to update).

The changes that you make to resource and descriptor definitions by using the

UPDATE and IMPORT commands exist during the current execution of the IMS system and are recoverable across a warm or emergency restart. To preserve the changes across a cold start, export the updated definitions to an RDDS before IMS terminates, and then import the stored definitions from the RDDS back into IMS either during cold start processing (by using the automatic import function), or when IMS is up and running (by using the IMPORT DEFN command).

If the attributes specified on the UPDATE command are already defined for the resource: v

No update is made v

No resources are quiesced v No log record is created v

A completion code of zero is returned

By taking no action, IMS avoids unnecessary processor usage.

Unlike the online change process where either all resource definitions are updated or no resource definitions are updated, each resource or descriptor definition can be updated individually.

Updating runtime database resource and descriptor definitions with the UPDATE command

With dynamic resource definition (DRD) enabled, you can update runtime resources and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

You cannot update database resource definitions if there is work in progress for the database, or if the database is currently in use.

Update runtime database resource and descriptor definitions using the UPDATE

DB and UPDATE DBDESC commands.

Chapter 2. Dynamic resource definition

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1.

Check for work in progress using a QRY DB SHOW(WORK) command. If there is work in progress, either: a.

Wait for the work to finish.

b.

Address the work in progress. Examples of work in progress include a command is in progress for the database, or the database is in use.

2.

Stop the database using either an UPDATE DB STOP(ACCESS) or /DBR DB command

3.

Issue an UPDATE DB or UPDATE DBDESC command specifying the values you want to change for the database or descriptor definitions, respectively.

Updating runtime application program resource and descriptor definitions with the UPDATE command

With dynamic resource definition (DRD) enabled, you can update runtime application program resources and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

You cannot update application program resource definitions if there is work in progress for the application program. In a local queues environment, if there are queued messages for transactions associated with the program being updated, the update fails. In a shared queues environment, if there are queued messages for a transaction that is associated with the program being updated, the update succeeds. However, the update might succeed on some IMS systems and fail on others.

Update runtime application program resource and descriptor definitions using the

UPDATE PGM and UPDATE PGMDESC commands.

1.

Check for work in progress using a QRY PGM SHOW(WORK) command. If there is work in progress, either: a.

Wait for the work to finish.

b.

Address the work in progress. Examples of work in progress include a command being in progress for the program or the program being scheduled.

2.

Check whether any transactions reference the program using a QRY PGM

SHOW(TRAN) command. If any of the program attributes you plan to update

(such as FP or BMPTYPE) conflict with any transactions that reference the program, before updating the program definition, you must either: a.

Delete the conflicting transaction definitions that reference the program.

b.

Update the transaction definitions to reference a different program before updating the program.

To delete a transaction, issue a DELETE TRAN command. To update a transaction, issue an UPDATE TRAN command.

3.

If the FP attribute is being changed from FP(E) to FP(N), determine whether any routing codes reference the program by using a QRY PGM SHOW(RTC) command. If there are routing codes that reference the program, before updating the program definition, you must either: v

Delete all the routing codes that reference the program.

v

Update the routing code definitions to reference a different program before updating the program.

50

System Definition

To delete a routing code associated with an FP(E) transaction, issue a DELETE

TRAN command. To delete a routing code associated with an FP(P) transaction, issue a DELETE RTC command.

4.

The next step varies depending on where the application program is running.

v

If the program is running in an IFP region, issue a /STOP REGION command to terminate the program.

v

If the program is running in a BMP or JBP region, either wait for the program to finish, or issue a /STOP REGION command to terminate the program.

v If the program is a BMP that is processing a WFI transaction, issue a /STOP

REGION command to terminate the program.

v

If the program is running in an MPP or JMP region, issue a /STOP PGM or

UPDATE PGM STOP(SCHD) command to terminate the program.

5.

Issue the UPDATE PGM or UPDATE PGMDESC command specifying the values you want to change for the application program or descriptor definitions, respectively.

If all the attributes specified by the UPDATE command are already defined for the resource, no update is made, no resources are quiesced, no log record is created, and a completion code of zero is returned. This avoids unnecessary overhead when no action needs to be taken.

For the details about parameters for the UPDATE and QUERY commands, see

IMS

Version 11 Commands, Volume 2: IMS Commands N-V

.

Updating runtime Fast Path routing code resource and descriptor definitions with the UPDATE command

With dynamic resource definition (DRD) enabled, you can update runtime Fast

Path routing code resource and descriptor definitions dynamically, eliminating the requirement to use the online change process or the batch system definition process with an IMS cold start.

If the program is scheduled, the routing code cannot be updated. If the program is scheduled, you must stop the region before you issue the UPDATE RTC command.

Update runtime Fast Path routing code resources and descriptor definitions using the UPDATE RTC and UPDATE RTCDESC commands.

1.

Check for work in progress by using a QRY RTC SHOW(WORK) command. If there is work in progress, either: v

Wait for the work to finish.

v

Address the work in progress.

Examples of work in progress include a command in progress for the routing code or an active routing code.

2.

If the application program is running in an IFP region, terminate the program by using a /STOP REGION command.

3.

Issue an UPDATE RTC or UPDATE RTCDESC command, specifying values you want to change for the Fast Path routing code resources or descriptor definitions. To update a routing code associated with a Fast Path exclusive

FP(E) transaction, you must issue an UPDATE TRAN command. The UPDATE

TRAN command updates the transaction definition and the associated routing code definition.

Chapter 2. Dynamic resource definition

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For the details about parameters for the UPDATE and QUERY commands, see

IMS

Version 11 Commands, Volume 2: IMS Commands N-V

.

If you are using a set of system resource definition data sets (RDDSs) to store your

Fast Path routing code resource and descriptor definitions, the routing codes associated with both Fast Path potential FP(P) and FP(E) transactions are maintained in the RDDS.

Updating runtime transaction resource and descriptor definitions with the UPDATE command

With dynamic resource definition (DRD) enabled, you can update runtime resources and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

You cannot update a transaction if it is in use. If a transaction is in use, the update fails. In a local queues environment, if there are queued messages for the transaction, the update fails. In a shared queues environment, if there are queued messages for the transaction, the update succeeds.

Update runtime transaction resource and descriptor definitions using the UPDATE

TRAN and UPDATE TRANDESC commands.

1.

Check for work in progress by using a QRY TRAN SHOW(WORK) command and either wait for the work to finish or address the work in progress.

Examples of work in progress are a command in progress for the transaction, a scheduled transaction, a transaction in conversation, or a suspended transaction.

v

To wait for work in progress to complete, issue either a /PURGE TRAN or

UPDATE TRAN STOP(Q) command to stop the transaction from being queued, but to allow existing queued messages to be processed.

v

If you do not want to wait for work in progress, or if the transaction is a

WFI transaction, or if the transaction is running in a PWFI=Y MPP region, stop the transaction by issuing a /STOP TRAN or UPDATE TRAN

STOP(SCHD,Q) command. If you are stopping the transaction in a non-shared queues environment, no messages can be queued for the transaction. To dequeue messages for the transaction, issue the QUEUE

TRAN OPTION(DEQALL) command.

2.

The next step varies depending on where the transaction is running.

v

If the transaction is running in an IFP region, terminate the program by issuing a /STOP REGION.

v

If the transaction is a non-WFI transaction running in a message-driven BMP, either wait for the program to finish, or terminate the program by issuing a

/STOP REGION command.

v If the transaction is a WFI transaction running in a message-driven BMP, terminate the program by issuing a /STOP REGION command.

3.

If the transaction has messages on the suspend queue, and you are running in a non-shared queues environment, you must either: v

Process the messages on the suspend queue.

v

Delete the messages. To delete the messages on the suspend queue, stop the transaction by issuing a /STOP TRAN or UPDATE TRAN STOP(SCHD) command.

52

System Definition

a.

Move the messages to the ready queue by issuing either a /DEQ SUSPEND or UPDATE TRAN START(SUSPEND) command.

b.

After the messages are on the ready queue, you can delete them by issuing a QUEUE TRAN OPTION(DEQALL) command.

4.

Issue the UPDATE TRAN or UPDATE TRANDESC command for the resource or descriptor definition you want to update, respectively.

For the details about parameters for the UPDATE and QUERY commands, see

IMS

Version 11 Commands, Volume 2: IMS Commands N-V

.

Updating runtime resource and descriptor definitions in an

IMSplex with the UPDATE command

If you have a mixture of DRD-enabled and DRD-disabled IMS systems in an

IMSplex, you can update resources or descriptor definitions for this environment.

Perform the following procedure:

1.

Perform an online change process for the IMS.MODBLKS data set on the IMS systems that have not migrated to DRD.

2.

Issue UPDATE commands for the resource or descriptor definitions you want to update on the IMS systems that have DRD enabled.

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Deleting runtime resource and descriptor definitions

When dynamic resource definition (DRD) is enabled, you can use the DELETE command to delete runtime resource and descriptor definitions dynamically, eliminating the requirement to use the online change process or to cold start IMS.

Although the overall process for deleting runtime database, application program, transaction, and routing code definitions is the same, there are minor variations in the steps you perform.

The resource and descriptor definitions that you delete dynamically using the

DELETE command remain deleted across a warm or emergency restart.

Each resource or descriptor definition is deleted individually, unlike the online change process, where either all resources or descriptor definitions are deleted or no resources or descriptor definitions are deleted.

Deleting runtime resource and descriptor definitions when using an RDDS

To delete runtime resource and descriptor definitions from IMS and from an

RDDS, perform the following procedure:

1.

Issue the DELETE command locally at each IMS that contains the runtime definitions.

If definitions of more than one type are being deleted, issue multiple different

DELETE commands (according to the type of resource or descriptor definitions you want to delete).

If you have set up automatic export to an RDDS, automatic export occurs at system checkpoint and removes the deleted definitions from the system RDDS.

2.

If you have not set up automatic export to an RDDS, issue the EXPORT command at each IMS from which the definitions were deleted to ensure the removal of deleted definitions from the system RDDS (or non-system RDDS).

Chapter 2. Dynamic resource definition

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During cold start processing by using the automatic import function.

v

After IMS is up and running by using the IMPORT DEFN command.

Restrictions

You cannot delete a runtime resource definition if the resource is in use. Examples of resources in use include: v

A database that is being accessed by an application program v

A database that is referenced by the program specification block (PSB) for an existing program v

A /STOP or UPDATE command that is in progress for the resource v

An application program that is scheduled to run v

An active routing code v

A transaction with messages queued for it v

A transaction that has any work in progress

If you attempt to delete a resource that is in use, the delete attempt fails. In a sysplex environment, the delete attempt might succeed on some IMS systems and fail on others.

You cannot delete the following resources that are supplied by IMS: DBFDSRT1,

DFSDSDB1, DFSDSPG1, DFSDSTR1, and DBF#FPU0.

You cannot delete a HALDB master database resource unless it has no partitions defined and you have issued a /DBRECOVERY command for the database.

Related reference

:

IMPORT command (Commands)

DELETE commands (Commands)

Deleting runtime database resource and descriptor definitions with the DELETE command

With dynamic resource definition (DRD) enabled, you can delete runtime resource and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

Delete runtime database resource and descriptor definitions using the DELETE DB and DELETE DBDESC commands.

1.

Check for work in progress with a QRY DB SHOW(WORK) command. If there is work in progress, either: v

Wait for the work to finish.

v Address the work in progress.

2.

Determine whether any application programs reference the database by issuing a QRY DB SHOW(PGM) command. The DELETE DB command fails if any programs reference the database. If a program references the database, before deleting the database, you must either:

54

System Definition

v

Delete the programs that reference the database. If you decide to delete the programs that reference the database, and if there are transactions or routing codes that reference the programs, they must be deleted first.

v

Perform an online change to delete the PSB from ACBLIB.

v

Update the PSB so that it does not reference the database.

3.

The next step varies depending on whether the resource to be deleted is a database with secondary or logical relationships, an MSDB, or a HALDB master database.

v If the resource to be deleted is a database with secondary indexes or logical relationships, remove the relationships by performing these steps: a.

Update the database description (DBD) to remove the relationships.

b.

Run the Database Description Generation (DBDGEN) utility.

c.

Run the Application Control Block (ACB) Maintenance utility.

d.

Bring the updated DBDs and ACBs online using an online change process.

v

If the resource to be deleted is a main storage database (MSDB), perform these steps: a.

Use the MSDB Maintenance utility (DBFDBMA0) to remove segments from the MSDBINIT data set.

b.

Delete the MSDB from any PSB that references it using the DELETE

DBD= action control statement of DBFDBMA0.

c.

Perform a PSBGEN for the PSB that was modified.

d.

Perform an ACBGEN for the PSB that was modified.

e.

Perform an ACBGEN for the DBD of the MSDB that was deleted from the PSB.

f.

Either change or remove the appropriate DBFMSDBx procedure that is in the IMS.PROCLIB data set.

g.

Shut down IMS normally using the /CHE FREEZE command.

h.

Copy the above ACBLIB to both the active and inactive ACBLIB.

i.

Normally restart IMS using the /NRE command specified with the

MSDBLOAD keyword to refresh the MSDBs.

v

If the resource to be deleted is a HALDB master database, perform these steps: a.

Issue a /DBRECOVERY command.

The /DBRECOVERY command removes this IMS system's knowledge of the HALDB partitions and stops the HALDB master database so that it can be deleted.

4.

Stop the database using either a /DBR DB or an UPDATE DB STOP(ACCESS) command. A database must be successfully stopped by /DBR command before it can be deleted. Because the MSDB is no longer in the ACBLIB, IMS does not know that the database was previously an MSDB and allows the /DBR command.

5.

Issue the DELETE DB or DELETE DBDESC command to delete the database resource or descriptor definition, respectively.

Chapter 2. Dynamic resource definition

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Deleting runtime application program resource and descriptor definitions with the DELETE command

With dynamic resource definition (DRD) enabled, you can delete runtime application program resources and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

Delete runtime application program resource and descriptor definitions using the

DELETE PGM and DELETE PGMDESC commands.

1.

Check for work in progress with a QRY PGM SHOW(WORK) command. If there is work in progress, either: a.

Wait for the work to finish.

b.

Address the work in progress.

2.

Determine whether any transactions reference the program by using a QRY

PGM SHOW(TRAN) command. The DELETE PGM command fails if any transactions reference the program. If a transaction references the program, before deleting the program you must either: v Delete the transactions that reference the program by issuing a DELETE

TRAN command.

v

Update the transactions to reference a different program by using the

UPDATE PGM command.

3.

Determine whether any routing codes reference the program by using a QRY

PGM SHOW(RTC) command. The DELETE PGM command fails if any routing codes reference the program. If a routing code references the program, before deleting the program you must either: v

Delete the routing codes that reference the program.

To delete a routing code associated with a Fast Path exclusive FP(E) transaction, issue a DELETE TRAN command.

To delete a routing code associated with a Fast Path potential FP(P) transaction, issue a DELETE RTC command.

v

Update the routing code to reference a different program using the UPDATE

RTC command.

To update a routing code associated with an FP(E) transaction, issue an

UPDATE TRAN command.

To update a routing code associated with an FP(P) transaction, issue an

UPDATE RTC command.

4.

The next step varies depending on where the application program is running.

v

If the program is running in an IFP region or is a BMP processing a WFI transaction, issue a /STOP REGION command to terminate the program.

v

If the program is running in a BMP or JBP region, either: a.

Wait for the program to finish.

b.

Issue a /STOP REGION command to terminate the program.

v

If the program is running in an MPP or JMP region, issue a /STOP PGM or

UPDATE PGM STOP(SCHD) command to terminate the program.

5.

Issue the DELETE PGM or DELETE PGMDESC command to delete the application program resource or descriptor definition, respectively.

56

System Definition

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Deleting runtime Fast Path routing code resource and descriptor definitions with the DELETE command

With dynamic resource definition (DRD) enabled, you can delete runtime Fast Path routing code resource and descriptor definitions dynamically, eliminating the need to use the online change process or the batch system definition process with an

IMS cold start.

Delete runtime Fast Path routing code resources and descriptor definitions using the DELETE RTC and DELETE RTCDESC commands.

1.

Check for work in progress by issuing a QRY RTC SHOW(WORK) command. If there is work in progress, either: v

Wait for the work to finish.

v

Address the work in progress.

2.

The next step can vary based on whether the transaction is associated with a

Fast Path potential FP(P) or Fast Path exclusive FP(E) transaction.

v

Delete a routing code that is associated with a Fast Path potential transaction using the DELETE RTC command. If the program is scheduled, the routing code cannot be deleted and you must stop the region before you issue the

DELETE RTC command.

v

Delete a routing code that is associated with a Fast Path exclusive transaction using the DELETE TRAN command. The DELETE RTC command fails.

v

Delete a runtime routing code descriptor definition by issuing the DELETE

RTCDESC command.

Deleting runtime transaction resource and descriptor definitions with the DELETE command

With dynamic resource definition (DRD) enabled, you can delete runtime resource and resource descriptors dynamically, eliminating the need to use the online change process or the batch system definition process with an IMS cold start.

Delete runtime transaction resource and descriptor definitions using the DELETE

TRAN and DELETE TRANDESC commands.

1.

Check for work in progress with a QRY TRAN SHOW(WORK) command and either: v

Wait for the work to finish.

v

Address the work in progress.

Examples of work include a command in progress for the transaction, or the transaction is either scheduled, in conversation, or suspended.

2.

To wait for the work in progress to complete, issue either a /PURGE TRAN or

UPDATE TRAN STOP(Q) command to stop the transaction from being queued, but to allow existing queued messages to be processed.

3.

If you do not want to wait for the work in progress to complete, or if the transaction is a WFI transaction, stop the transaction by using a /STOP TRAN or UPDATE TRAN STOP(SCHD,Q) command. If you are stopping the transaction in a non-shared queues environment, no messages can be queued for the transaction. To dequeue messages for the transaction, issue the QUEUE

TRAN OPTION(DEQALL) command.

4.

The next step can vary depending on where the transaction is running.

Chapter 2. Dynamic resource definition

57

v

If the transaction is running in a PWFI=Y MPP region, stop the transaction by using a /STOP TRAN or UPDATE TRAN STOP(SCHD,Q) command. If you are stopping the transaction in a non-shared queues environment, no messages can be queued for the transaction. To dequeue messages for the transaction, issue the QUEUE TRAN OPTION(DEQALL) command.

v

If the transaction is running in an IFP region, terminate the program by issuing a /STOP REGION command.

v If the transaction is a non-WFI transaction running in a message-driven BMP, either wait for the program to finish, or terminate the program by issuing a

/STOP REGION command.

v

If the transaction is a WFI transaction running in a message-driven BMP, terminate the program by issuing a /STOP REGION command.

5.

If the transaction has messages on the suspend queue and you are running in a non-shared queues environment, you must either process the messages on the suspend queue or delete the messages. To delete the messages on the suspend queue: a.

Stop the transaction by issuing a /STOP TRAN or UPDATE TRAN

STOP(SCHD) command.

b.

Move the messages to the ready queue by issuing a /DEQ SUSPEND or

UPDATE TRAN START(SUSPEND) command.

c.

After the messages are on the ready queue, delete them by issuing a

QUEUE TRAN OPTION(DEQALL) command.

6.

Issue the DELETE TRAN or DELETE TRANDESC command to delete the transaction resource or descriptor definition, respectively.

Deleting runtime resource and descriptor definitions in an

IMSplex with the DELETE command

If you have a mixture of DRD-enabled and DRD-disabled IMS systems in an

IMSplex, you can delete resource or descriptor definitions for this environment.

Perform the following procedure:

1.

Perform an online change process for the IMS.MODBLKS data set on the IMS systems that have not migrated to DRD.

2.

Issue DELETE commands for the resource or descriptor definitions you want to delete on the IMS systems that have DRD enabled.

Exporting resource and descriptor definitions

When resource and descriptor definitions are ready to be created in a resource definition data set (RDDS) as the stored resource and descriptor definitions, you can export them to the RDDS.

Use the automatic export function or the EXPORT DEFN TARGET(RDDS) command to save your current resource and descriptor definition to the RDDS.

Exporting resource and descriptor definitions to an RDDS

Use the automatic export function or the EXPORT DEFN TARGET(RDDS) command to save your current resource and descriptor definition to a resource definition data set (RDDS).

v

When exporting to a system RDDS, all the IMS resource and descriptor definitions must be exported. All definitions in the system RDDS are overwritten with the definitions being exported.

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System Definition

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When exporting to a non-system RDDS, all or some of the IMS resource and descriptor definitions can be exported. You can either overwrite the existing definitions with the new definitions or append the new definitions to the end of the data set.

v

Definitions for IMS resources such as the Fast Path utility (DBF#FPU0) and the

IMS defined descriptors (DBFDSRT1, DFSDSDB1, DFSDSPG1, and DFSDSTR1) cannot be exported.

Exporting resource and descriptor definitions with automatic export

Perform the following procedure to set up automatic export of resource and descriptor definitions to an RDDS:

1.

Define two or more system resource definition data sets to IMS by using the

RDDSDSN() parameter in the DYNAMIC_RESOURCES section of the

DFSDFxxx member in the IMS PROCLIB data set.

If you are using automatic import or automatic export, each IMS system must have its own set of system RDDSs.

2.

Specify AUTOEXPORT=AUTO or AUTOEXPORT=RDDS in the

DYNAMIC_RESOURCES section in the DFSDFxxx member of the IMS

PROCLIB data set.

Resource and descriptor definitions are exported to the oldest RDDS at checkpoint time if the definitional attributes of one or more resources has changed since the last checkpoint.

Exporting resource and descriptor definitions with the EXPORT command

Use the EXPORT DEFN TARGET(RDDS) command to export resource and descriptor definitions to an RDDS.

Resource and descriptor definitions are either written to the data set specified by the RDDSDSN() command keyword, or to the system RDDS containing the oldest data. A system RDDS is one of the RDDS data sets that is defined with the

RDDSDSN= parameter in the DYNAMIC_RESOURCES section of the DFSDFxxx member of the IMS PROCLIB data set. A system RDDS contains all the resource and descriptor definitions for a single IMS system.

Related concepts

:

Shutting down an IMS system that uses dynamic resource definition

(Operations and Automation)

Related reference

:

“DYNAMIC_RESOURCES section of the DFSDFxxx member” on page 683

EXPORT command (Commands)

Importing resource and descriptor definitions

With dynamic resource definition (DRD) enabled, you can import resource and descriptor definitions from a resource definition data set (RDDS) by using the automatic import function or the IMPORT command.

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You can also use the IMS Manage Resources application that is available from the

IMS Application Menu (option 2) to import resource and descriptor definitions into

IMS.

Recommendation:

Anticipating that you might eventually have to back out the changes that were made by using the IMPORT DEFN command, perform these tasks: v

Establish a baseline backout recovery point by issuing an EXPORT DEFN

TARGET(RDDS) command to export all existing resources and descriptors to a non-system RDDS. If you must back out system definitions afterwards, you can use this set of resources and descriptors with an IMPORT DEFN command to restore the resources and descriptors.

v

Specify OPTION(ABORT) on the IMPORT DEFN command so that IMS processes the resource definitions as a group. Either all or none of the definitions are imported.

v

If you specify NAME(*) on the IMPORT DEFN command, command responses are returned only for the resource and descriptor names that resulted in an error.

Therefore, also specify OPTION(ABORT, ALLRSP) to obtain the command responses for all the resource and descriptor names that are processed.

v

Save the output from the IMPORT DEFN OPTION(ABORT, ALLRSP) command, which lists all the resources and descriptor names, in case you must back out the changes made by the IMPORT command.

Related concepts

:

Managing IMS resources by using TSO SPOC (Operations and Automation)

Modifying system resources online (Operations and Automation)

Related reference

:

IMPORT command (Commands)

Importing resource and descriptor definitions by using the automatic import function

With dynamic resource definition (DRD) enabled, you can enable the automatic import function so that resource and descriptor definitions are imported to IMS during IMS cold start processing.

For IMS to automatically import definitions from a system RDDS, IMS must be enabled with DRD.

For IMS to automatically import definitions from a system RDDS,

AUTOIMPORT=RDDS or AUTOIMPORT=AUTO must be specified in the

DYNAMIC_RESOURCES section of the DFSDFxxx member and all of the conditions listed in the description of the parameter must be true.

With DRD and the automatic import function enabled, resource definitions are imported from the IMS.MODBLKS data set, or resource and descriptor definitions are imported from a system RDDS. When a resource or descriptor definition is imported, IMS creates the control blocks that are used to manage the resource.

Information, such as the attributes of the resource or descriptor and the status of the resource, is saved in internal control blocks. The information kept in the control blocks is referred to as the

runtime resource or descriptor definition

. When IMS is up and running, you can use the IMPORT DEFN SOURCE(RDDS) command to import resource and descriptor definitions from a system or non-system RDDS.

v

To enable automatic import from an RDDS:

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| 1.

Make sure the conditions for automatic import from an RDDS are true.

If all of the following conditions are true, automatic import from an RDDS is enabled:

– Two or more system RDDSs are defined in the DFSDFxxx member of the

IMS PROCLIB data set.

– All the defined RDDSs can be allocated and read.

– At least one of the RDDSs contains valid resource and descriptor definitions.

2.

Specify AUTOIMPORT=RDDS or AUTOIMPORT=AUTO in the

DYNAMIC_RESOURCES section of the DFSDFxxx member of the IMS

PROCLIB data set.

v

To enable automatic import from the IMS.MODBLKS data set:

1.

Make sure the conditions for automatic import from the MODBLKS data set are true.

If all of the following conditions are true, automatic import from the

MODBLKS data set is enabled:

– The MODBLKS data set exists.

– No RDDSs are defined in the DFSDFxxx member of the IMS PROCLIB data set.

– The MODBLKS data set exists, and all the defined system RDDSs are empty.

2.

Specify AUTOIMPORT=MODBLKS in the DYNAMIC_RESOURCES section of the DFSDFxxx member of the IMS PROCLIB data set.

Related reference

:

“DYNAMIC_RESOURCES section of the DFSDFxxx member” on page 683

“COMMON_SERVICE_LAYER section of the DFSDFxxx member” on page 674

Importing resource and descriptor definitions from an RDDS by using the IMPORT command

After IMS is up and running, use the IMPORT DEFN command to import resource and descriptor definitions from a resource definition data set (RDDS).

If the definition is for a resource or descriptor that is unknown to IMS, IMS creates the internal control blocks needed to manage the resource or descriptor. If the definition is for a resource or descriptor that exists in IMS, the import of that definition fails.

Resource and descriptor definitions can be imported from either the system RDDS with the most current resource and descriptor definitions, or an RDDS that is specified using the RDDSDSN() keyword on the IMPORT DEFN SOURCE(RDDS) command. The RDDS that is specified with the RDDSDSN() command keyword can be a system RDDS or a non-system RDDS. A system RDDS is one of the RDDS data sets that is defined with the RDDSDSN() parameter in the

DYNAMIC_RESOURCES section of the DFSDFxxx member of the IMS PROCLIB data set. A system RDDS contains all the resource and descriptor definitions for a single IMS system. If you are using the automatic import or automatic export function, each IMS system must have its own set of system RDDS data sets.

If an RDDS contains multiple definitions for the same resource or descriptor, the last definition imported is the definition that is used to create the runtime resource or descriptor definition.

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Resources defined by IMS such as the Fast Path utility (DBF#FPU0) and the IMS defined descriptors (DBFDSRT1, DFSDSDB1, DFSDSPG1, and DFSDSTR1) are restricted and therefore not allowed to be specified on the IMPORT DEFN command.

Backing out runtime resources imported with the IMPORT command

If you created runtime resources definitions by importing definitions from a resource definition data set (RDDS) by using the IMPORT DEFN SOURCE(RDDS) command, you can back out those changes to your online system both with and without a cold start of IMS.

Related reference

:

IMPORT command (Commands)

DELETE commands (Commands)

EXPORT command (Commands)

Backing out runtime definitions imported by the IMPORT command with a cold start of IMS

If you created runtime resources definitions by importing definitions from a resource definition data set (RDDS) by using the IMPORT DEFN command, you can back out the changes to your online system with a cold start of IMS.

Prerequisite:

This option requires that all the resource and descriptor definitions were exported to a non-system RDDS before the original IMPORT DEFN command was issued.

For resources imported from an RDDS, perform the following steps:

1.

Cold start IMS with no MODBLKS resources defined (by specifying

AUTOIMPORT=N in the Dynamic Resources section of the DFSDFxxx member of the IMS PROCLIB data set).

2.

Issue the IMPORT DEFN SOURCE(RDDS) command to import all the definitions from the non-system RDDS that was created for backout recovery before the original IMPORT DEFN command was issued.

After the backout is complete, if you are running with system RDDSs defined, issue the EXPORT DEFN TARGET(RDDS) command to export the current definitions to a system RDDS.

Backing out runtime definitions imported by the IMPORT command without a cold start of IMS

If you created runtime resources definitions by importing definitions from a resource definition data set (RDDS) by using the IMPORT DEFN command, you can back out the changes to your online system without a cold start of IMS.

Prerequisite:

This option requires that all the resource and descriptor definitions were exported to a non-system RDDS before the original IMPORT DEFN command was issued. It also requires that you saved the output generated from the IMPORT

DEFN command, which shows the resource and descriptor definitions that were created or updated as a result of the IMPORT DEFN command.

To back out the changes:

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| Issue DELETE commands for any resource and descriptor definitions that were created by the IMPORT DEFN command.

After the backout is complete, if you are running with system RDDSs defined, issue the EXPORT DEFN TARGET(RDDS) command to export the current definitions to a system RDDS.

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Maintaining your dynamic resource definition environment

After you have set up your IMS systems to support dynamic resource definition

(DRD), it is important to establish processes to maintain your DRD environment.

Here are some steps to follow to establish processes to maintain your DRD environment.

Enabling automatic export to an RDDS

Enable the automatic export function to an RDDS by: v

Defining two or more system resource definition data sets.

v Specifying AUTOEXPORT=AUTO in the DYNAMIC_RESOURCES section of the

DFSDFxxx member in the IMS PROCLIB data set.

When automatic export is enabled, your resource and descriptor definitions are automatically exported to an RDDS at IMS checkpoint if the attribute values of one or more of your resources or descriptors have changed since the last IMS checkpoint. If you must perform a cold start later, IMS imports the resource and descriptor definitions from the RDDS and creates the runtime resource and descriptor definitions that it must run.

Exporting definitions to an RDDS with the EXPORT command

If the attribute values of one or more of your resources or descriptors have changed since the last IMS checkpoint, save the definitions to an RDDS.

As an alternative to enabling the automatic export function to an RDDS, use the

EXPORT DEFN TARGET(RDDS) command to save your current resource and descriptor definition to an RDDS.

Enabling automatic import

Enable the automatic import function by specifying AUTOIMPORT=AUTO in the

DYNAMIC_RESOURCES section of the DFSDFxxx member of the IMS PROCLIB data set. When AUTOIMPORT=AUTO is specified, IMS determines whether to enable automatic import processing. If IMS enables automatic import, it also determines the data source from which to import the definitions.

Whether the conditions for automatic import that are listed in the description of the AUTOIMPORT parameter are met determines if automatic import from a

MODBLKS data set or an RDDS takes place.

If you delete runtime resource definitions using a DELETE command and then cold start IMS, the deleted resource definitions reappear if the resource definitions are automatically imported from the original IMS.MODBLKS data set instead of the RDDS that contains the most current definitions.

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Removing IMS.MODBLKS data sets

When DRD is enabled, the IMS.MODBLKS data sets are no longer required. After you are satisfied with the setup of your DRD environment and it is running successfully, you can remove the IMS.MODBLKS data sets. If automatic import is enabled, resource and descriptor definitions are imported during IMS cold start from the RDDS that contains the most current data. However, you can continue to use the IMS.MODBLKS data set as the source for all of your resource definitions, instead of an RDDS. If you choose to continue using the IMS.MODBLKS data set, keep your system definition macros synchronized with the changes you make dynamically using DRD commands.

Synchronizing the contents of IMS.MODBLKS

As you migrate to DRD, keep resource definitions that are in the IMS.MODBLKS

data set synchronized with the resource definitions that are in the RDDS. This synchronization enables you to maintain a viable IMS.MODBLKS data set if you must disable DRD and fall back to using the online change process for the resources in the IMS.MODBLKS data set. To keep your IMS.MODBLKS data set synchronized with your online definitions, update your static macro definitions with the changes that you make dynamically using type-2 commands. When changes are made dynamically, perform a MODBLKS system definition to add, change, or delete resources from the IMS.MODBLKS data set.

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Converting resource definitions into IMS stage 1 macro statements or

IMS type-2 CREATE commands

After you create resource definitions and export them to a resource definition data set (RDDS), you can use the RDDS Extraction utility (DFSURDD0) to convert the resource definitions that are in the RDDS into either IMS stage 1 macro statements, or IMS type-2 CREATE commands.

You can convert the resource definitions into IMS stage 1 APPLCTN, DATABASE,

RTCODE, and TRANSACT macro statements.

The type-2 CREATE commands into which you can convert the resource definitions include: v

CREATE DB v

CREATE DBDESC v

CREATE PGM v

CREATE PGMDESC v

CREATE RTC v CREATE RTCDESC v

CREATE TRAN v CREATE TRANDESC

For additional information about the Resource Definition Data Set (RDDS)

Extraction utility, see

IMS Version 11 System Utilities

.

Disabling dynamic resource definition

You might need to disable the dynamic resource definition (DRD) process and fall back to using the online change process.

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With DRD enabled, ensure that the IMS.MODBLKS data set has a complete set of the current resource definitions. This complete set includes resource definitions that were originally in the IMS.MODBLKS data set or in the RDDS at cold start, and that were not changed or deleted dynamically. It also includes any resource definitions that were added or changed dynamically since cold start. This check enables you to fall back to using online change for the IMS.MODBLKS data set with all the resources that were either defined originally by system definition or defined dynamically.

Perform the following procedure to disable the DRD process and fall back to using the online change process:

1.

Use one of the following methods to synchronize your IMS.MODBLKS data set with your online definitions: v

Update your static macro definitions with the changes that you make dynamically using type-2 commands. When changes are made dynamically, perform a MODBLKS system definition to update the IMS.MODBLKS data set.

v

Use the Resource Definition Data Set (RDDS) Extraction utility (DFSURDD0) to extract the resource definitions to create Stage-1 macro statements from the stored resource definitions in an RDDS. Then perform a MODBLKS system definition to update the IMS.MODBLKS data set.

2.

Shut down IMS normally.

3.

Enable online change for the IMS.MODBLKS data set: a.

Perform one of the following steps: v

Remove the MODBLKS keyword from the DFSCGxxx member of the IMS

PROCLIB data set. Optionally, also remove the MODBLKS keyword from the COMMON_SERVICE_LAYER section of the DFSDFxxx member of the

IMS PROCLIB data set.

If both members are defined, any values specified in DFSCGxxx override those values that are in DFSDFxxx.

v

Change the value of the MODBLKS keyword from DYN to OLC in the

DFSCGxxx member of the IMS PROCLIB data set. Optionally, also change the value of the MODBLKS keyword from DYN to OLC in the

COMMON_SERVICE_LAYER section of the DFSDFxxx member of the

IMS PROCLIB data set.

If both members are defined, any values specified in DFSCGxxx override those values that are in DFSDFxxx.

b.

Specify AUTOIMPORT=MODBLKS or AUTOIMPORT=AUTO in the

DFSDFxxx member of the IMS PROCLIB data set.

c.

Remove all RDDS statements from the DFSDFxxx member of the IMS

PROCLIB data set.

4.

Ensure that the IMS JCL includes the MODBLKS DD statement.

5.

Cold start IMS. An IMS cold start creates runtime resource definitions from the stored resource definitions in the IMS.MODBLKS data set. The online change process for the IMS.MODBLKS data set is enabled again (and DRD is disabled).

No variations of the CREATE and DELETE commands are allowed in a non-DRD environment. Some variations of the UPDATE command are allowed.

You can issue an EXPORT DEFN TARGET(RDDS) command to export to a non-system RDDS.

6.

Reestablish your in-house procedures that use the online change process for the

IMS.MODBLKS data set, and disable the in-house procedures that use DRD commands.

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