Managing Network File Systems in Oracle® Solaris 11.3

Managing Network File Systems in
®
Oracle Solaris 11.3
Part No: E54789
October 2017
Managing Network File Systems in Oracle Solaris 11.3
Part No: E54789
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Contents
Using This Documentation ................................................................................ 11
1 About Network File Systems ......................................................................... 13
About the NFS Service .................................................................................. 13
About Autofs ................................................................................................ 14
NFS Terminology .......................................................................................... 15
NFS Servers and Clients ......................................................................... 15
NFS File Systems .................................................................................. 15
Features of the NFS Service ............................................................................ 16
NFS Version 2 Protocol .......................................................................... 16
NFS Version 3 Protocol .......................................................................... 16
NFS Version 4 Protocol .......................................................................... 17
Controlling NFS Versions ....................................................................... 18
NFS ACL Support ................................................................................. 18
NFS Over TCP ..................................................................................... 18
NFS Over UDP ..................................................................................... 19
Overview of NFS Over RDMA ............................................................... 19
Network Lock Manager and NFS ............................................................. 19
NFS Large File Support ......................................................................... 19
NFS Client Failover ............................................................................... 20
Kerberos Support for the NFS Service ...................................................... 20
WebNFS Support ................................................................................... 20
RPCSEC_GSS Security Flavor ................................................................ 20
Extensions for NFS Mounting ................................................................. 21
Security Negotiation for the WebNFS Service ............................................ 21
NFS Server Logging .............................................................................. 21
Autofs Features ..................................................................................... 22
Significant Changes in the Oracle Solaris 11 Release ........................................... 22
5
Contents
2 Network File System Features ...................................................................... 25
How the NFS Service Works ........................................................................... 25
NFS Over RDMA ................................................................................. 26
Version Negotiation in NFS .................................................................... 28
Features in NFS Version 4 ...................................................................... 28
UDP and TCP Negotiation ...................................................................... 38
File Transfer Size Negotiation ................................................................. 39
How File Systems Are Mounted in NFS Version 3 ...................................... 39
Effects of the -public Option and NFS URLs When Mounting ...................... 40
Client-Side Failover ............................................................................... 41
How NFS Server Logging Works ............................................................. 43
How the WebNFS Service Works ............................................................. 43
How WebNFS Security Negotiation Works ................................................ 44
WebNFS Limitations With Web Browser Use ............................................. 45
Secure NFS Systems .............................................................................. 45
How Mirror Mounts Work .............................................................................. 49
Mounting a File System Using Mirror Mounts ............................................ 49
Unmounting a File System Using Mirror Mounts ........................................ 49
How NFS Referrals Work ............................................................................... 50
When to Use NFS Referrals .................................................................... 50
Creating an NFS Referral ....................................................................... 50
Removing an NFS Referral ..................................................................... 51
How Autofs Works ........................................................................................ 51
How Autofs Navigates Through the Network ............................................. 53
Autofs Maps ......................................................................................... 53
How Autofs Starts the Navigation Process ................................................. 59
Autofs Mount Process ............................................................................ 60
How Autofs Selects the Nearest Read-Only Files for Clients ......................... 61
Autofs and Weighting ............................................................................ 65
Variables in an Autofs Map Entry ............................................................ 65
Maps That Refer to Other Maps ............................................................... 66
Executable Autofs Maps ......................................................................... 67
Default Autofs Behavior With Name Services ............................................ 67
Autofs Reference ........................................................................................... 69
Autofs and Metacharacters ...................................................................... 69
Autofs and Special Characters ................................................................. 70
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Contents
3 Administering Network File Systems ............................................................ 71
About Administering Network File Systems ....................................................... 71
Automatic File System Sharing ........................................................................ 72
Task Map for File System Sharing ........................................................... 72
▼ How to Set Up Automatic File System Sharing ...................................... 72
▼ How to Enable NFS Server Logging .................................................... 73
Mounting File Systems ................................................................................... 74
Mounting File Systems Task Map ............................................................ 74
▼ How to Mount a File System at Boot Time ........................................... 75
▼ How to Mount a File System From the Command Line ........................... 76
Mounting With the Automounter .............................................................. 77
▼ How to Mount All File Systems From a Server ...................................... 77
▼ How to Use Client-Side Failover ........................................................ 77
▼ How to Disable Mount Access for One Client ....................................... 78
▼ How to Mount an NFS File System Through a Firewall ........................... 79
Mount an NFS File System by Using an NFS URL ..................................... 79
Displaying Information About File Systems Available for Mounting ............... 80
Setting Up the NFS Service ............................................................................ 81
Starting and Stopping the NFS Service ...................................................... 81
Starting and Stopping the Automounter ..................................................... 81
Selecting Different Versions of NFS ......................................................... 82
Administering the Secure NFS System .............................................................. 85
▼ How to Set Up a Secure NFS Environment With DH Authentication .......... 85
Administering WebNFS .................................................................................. 87
Planning for WebNFS Access .................................................................. 87
▼ How to Enable WebNFS Access ......................................................... 88
Accessing an NFS URL by Using a Browser .............................................. 89
Enabling WebNFS Access Through a Firewall ............................................ 90
Administering NFS Referrals ........................................................................... 90
▼ How to Create and Access an NFS Referral .......................................... 90
▼ How to Remove an NFS Referral ........................................................ 91
Administering FedFS ..................................................................................... 91
Set Up a DNS Record for a FedFS Server ................................................. 91
▼ How to Create a Namespace Database ................................................. 92
▼ How to Use a Secured Connection to the NSDB .................................... 93
▼ How to Create a FedFS Referral ......................................................... 94
7
Contents
4 Administering Autofs .................................................................................... 95
Autofs Administration .................................................................................... 95
Using SMF Parameters to Configure Your Autofs Environment ............................. 97
▼ How to Configure Your Autofs Environment Using SMF Parameters .......... 97
Administrative Tasks Involving Maps ............................................................... 97
Modifying the Maps ...................................................................................... 98
▼ How to Modify the Master Map ......................................................... 98
▼ How to Modify Indirect Maps ............................................................ 99
▼ How to Modify Direct Maps .............................................................. 99
Avoiding Mount Point Conflicts ....................................................................... 99
Accessing Non-NFS File Systems ................................................................... 100
Customizing the Automounter ........................................................................ 100
Setting Up a Common View of /home ..................................................... 100
▼ How to Set Up /home With Multiple Home Directory File Systems .......... 101
▼ How to Consolidate Project-Related Files Under a Common Directory ...... 102
▼ How to Set Up Different Architectures to Access a Shared Namespace ...... 104
▼ How to Support Incompatible Client Operating System Versions .............. 105
▼ How to Replicate Shared Files Across Several Servers ........................... 106
Autofs Security Restrictions .................................................................. 106
▼ How to Use a Public File Handle With Autofs ..................................... 107
▼ How to Use NFS URLs With Autofs ................................................. 107
Disabling Autofs Browsability ............................................................... 107
5 Commands for Managing Network File Systems ......................................... 111
NFS Commands .......................................................................................... 111
automount Command ........................................................................... 112
clear_locks Command ........................................................................ 113
fsstat Command ................................................................................ 113
mount Command .................................................................................. 114
umount Command ................................................................................ 120
mountall Command ............................................................................. 121
umountall Command ........................................................................... 121
sharectl Command ............................................................................. 122
share Command .................................................................................. 124
unshare Command .............................................................................. 129
shareall Command ............................................................................. 130
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Contents
unshareall Command .......................................................................... 130
showmount Command ........................................................................... 130
nfsref Command ................................................................................ 132
FedFS Commands ........................................................................................ 132
6 Troubleshooting Network File Systems ....................................................... 133
Strategies for NFS Troubleshooting ................................................................ 133
Commands for Troubleshooting NFS Problems ................................................. 134
nfsstat Command .............................................................................. 134
pstack Command ................................................................................ 136
rpcinfo Command .............................................................................. 137
snoop Command .................................................................................. 139
truss Command .................................................................................. 140
NFS Troubleshooting Procedures .................................................................... 140
▼ How to Check Connectivity on an NFS Client ..................................... 141
▼ How to Check the NFS Server Remotely ............................................ 142
▼ How to Verify the NFS Service on the Server ...................................... 143
▼ How to Restart NFS Service ............................................................. 145
Identifying the Host Providing the NFS Service ........................................ 145
▼ How to Verify Options Used With the mount Command ......................... 145
Troubleshooting Autofs ................................................................................. 146
Error Messages Generated by automount -v .............................................. 146
Miscellaneous Error Messages ............................................................... 148
Other Errors With Autofs ...................................................................... 150
NFS Error Messages .................................................................................... 150
7 Accessing Network File Systems ................................................................ 157
NFS Files ................................................................................................... 157
/etc/default/nfslogd File .................................................................. 158
/etc/nfs/nfslog.conf File .................................................................. 159
NFS Daemons ............................................................................................. 160
automountd Daemon ............................................................................ 161
lockd Daemon .................................................................................... 162
mountd Daemon ................................................................................... 163
nfs4cbd Daemon ................................................................................. 164
nfsd Daemon ...................................................................................... 164
9
Contents
nfslogd Daemon ................................................................................. 165
nfsmapid Daemon ............................................................................... 165
reparsed Daemon ............................................................................... 172
statd Daemon .................................................................................... 172
A NFS File Sharing Command Reference ....................................................... 173
Administering Network File Systems .............................................................. 173
Troubleshooting Network File Systems ............................................................ 174
Index ................................................................................................................ 175
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Using This Documentation
■
■
■
Overview – Describes how to administer and access the network file systems.
Audience – Technicians, system administrators, and authorized service providers.
Required knowledge – Basic and some advanced network administration skills.
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Using This Documentation
11
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
♦ ♦ ♦
1
C H A P T E R
1
About Network File Systems
This chapter provides an overview of the network file system (NFS) service, which can be
used to access file systems over the network. The NFS service enables any system to access
any other system's file systems. A system can assume the role of client, server, or both, at any
particular time on a network. Autofs is a client-side service used to mount the file systems that
are shared through the NFS service. Autofs is a file system structure that provides automatic
mounting. The chapter includes a discussion of the concepts necessary to understand the NFS
service and a description of the latest features in NFS and autofs.
This chapter contains the following topics:
■
■
■
■
■
“NFS Terminology” on page 15
“About the NFS Service” on page 13
“About Autofs” on page 14
“Features of the NFS Service” on page 16
“Significant Changes in the Oracle Solaris 11 Release” on page 22
Note - If your system has zones enabled and you want to use NFS in a non-global zone, see
“Non-Global Zones as NFS Clients” in Creating and Using Oracle Solaris 10 Zones.
About the NFS Service
The NFS service enables systems of different architectures that run different operating systems
to share file systems across a network.
The NFS environment can be implemented on different operating systems because NFS defines
an abstract model of a file system rather than an architectural specification. Each OS applies the
NFS model to its file system semantics. This model means that file system operations, such as
reading and writing, function as though the operations are accessing a local file.
Chapter 1 • About Network File Systems
13
About Autofs
The NFS service has the following benefits:
■
■
■
■
■
■
■
Enables multiple systems to use the same files so that everyone on the network can access
the same data
Reduces storage costs by having systems share applications instead of requiring local disk
space for each user application
Provides data consistency and reliability because all users can read the same set of files
Makes mounting of file systems transparent to users
Makes accessing of remote files transparent to users
Supports heterogeneous environments
Reduces system administration overhead
The NFS service makes the physical location of a file system irrelevant to the user. Instead of
having to place commonly used files on every system, you can share the original file from the
NFS server's file system. All other systems access the files across the network. Under NFS
operation, remote file systems are almost indistinguishable from local file systems.
About Autofs
File systems that are shared through the NFS service can be mounted by using automatic
mounting. Autofs, a client-side service, is a file system structure that provides automatic
mounting. The autofs file system is initialized by automount, which is run automatically when
a system is booted. The automount daemon, automountd, runs continuously, mounting and
unmounting remote file systems as necessary.
Whenever a client system that is running automountd tries to access a remote file system, the
daemon mounts the remote file system. This remote file system remains mounted for as long as
needed. If the remote file system is not accessed for a certain period of time, it is automatically
unmounted.
Mounting is not required at boot time, and the user no longer has to know the superuser
password to mount a directory. Users do not need to use the mount and umount commands. The
autofs service mounts and unmounts file systems as required without any intervention by the
user.
Mounting some file systems with the automountd command does not exclude the possibility of
mounting other systems with the mount command. A diskless computer must mount / (root),
/usr, and /usr/kvm through the mount command and the /etc/vfstab file.
For more information about the autofs service, see:
14
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
NFS Terminology
■
■
Table 6, “Tasks for administering Autofs,” on page 95
“How Autofs Works” on page 51
NFS Terminology
This section includes basic terminology that must be understood to work with the NFS service.
For more information about the NFS service, see Chapter 5, “Commands for Managing
Network File Systems”.
NFS Servers and Clients
The terms client and server describe the roles that a system assumes when sharing file systems.
Servers are systems that share their file systems over a network. The systems that access these
file systems are the clients.
Clients access files on the server by mounting the server's shared file systems. When a client
mounts a remote file system, the client does not make a copy of the file system. Rather, the
mounting process uses a series of remote procedure calls that enable the client to access
the server's shared file system transparently. The mount resembles a local mount. You can
type commands as if the file systems are local. For more information, see “Mounting File
Systems” on page 74.
After a file system has been shared on a server through an NFS operation, the file system can
be accessed from a client. You can mount an NFS file system automatically with autofs. For
information about autofs, see “About Autofs” on page 14. For information about tasks that
involve the share command and autofs, see “Automatic File System Sharing” on page 72
and Table 6, “Tasks for administering Autofs,” on page 95.
NFS File Systems
The objects that can be shared with the NFS service include any whole or partial directory tree
or a file hierarchy, including a single file. A system cannot share a file hierarchy that overlaps a
file hierarchy that is already shared. Peripheral devices such as modems and printers cannot be
shared.
In most UNIX system environments, a file hierarchy that can be shared corresponds to a file
system or to a portion of a file system. However, because NFS works across operating systems
Chapter 1 • About Network File Systems
15
Features of the NFS Service
and the concept of a file system might be meaningless in non-UNIX environments, the term file
system refers to a file or file hierarchy that can be shared and mounted with NFS.
Features of the NFS Service
This section describes important features of the NFS service.
NFS Version 2 Protocol
NFS Version 2, the first version of the NFS protocol is widely used. All Oracle Solaris releases
support the NFS Version 2 protocol.
NFS Version 3 Protocol
Unlike the NFS Version 2 protocol, the NFS Version 3 protocol can handle files that are
larger than 2 Gbytes. For information about handling large files in NFS, see “NFS Large File
Support” on page 19.
The NFS Version 3 protocol enables safe asynchronous writes on the server, which improves
performance by allowing the server to cache client write requests in memory. The client no
longer waits for the server to commit the changes to disk, so the response time is faster. Also,
the server can batch the requests, which improves the response time on the server.
Many Solaris NFS Version 3 operations return the file attributes, which are stored in the
local cache. Because the cache is updated more often, the requirement to perform a separate
operation to update this data arises less often. Therefore, the number of Remote Procedure Calls
(RPC) to the server is reduced, improving performance.
The process for verifying file access permissions has been improved. Version 2 generated a
“write error” message or a “read error” message if users tried to copy a remote file without the
appropriate permissions. In Version 3, the permissions are checked before the file is opened, so
the error is reported as an “open error.”
The NFS Version 3 protocol removes the 8 KB transfer size limit. Clients and servers can
negotiate whatever transfer size the clients and servers support, rather than conform to the 8
KB limit that Version 2 imposed. Note that in earlier Solaris implementations, the protocol
defaulted to a 32 KB transfer size. Starting with the Oracle Solaris 10 release, restrictions on
16
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Features of the NFS Service
wire transfer sizes were relaxed. The transfer size is based on the capabilities of the underlying
transport.
NFS Version 4 Protocol
The NFS Version 4 protocol represents the user ID and the group ID as strings. The nfsmapid
daemon is used by the NFS Version 4 client and server for the following mappings:
■
■
Map the user ID and group ID strings to local numeric IDs
Map the local numeric IDs to user ID and group ID strings
For more information about the nfsmapid daemon, see “NFS Daemons” on page 160.
Note that in NFS Version 4, the nfsmapid daemon, is used to map user IDs or group IDs
in Access Control List (ACL) entries on a server to user IDs or group IDs in ACL entries
on a client. The reverse is also true. For more information about user ID and group ID
mapping, see “ACLs and nfsmapid in NFS Version 4” on page 37 and “NFS ACL
Support” on page 18.
With NFS Version 4, when you unshare a file system, all the state information for any open files
or file locks in that file system is destroyed. In NFS Version 3, the server maintains any locks
that the clients had obtained before the file system was unshared. For more information about
unsharing a file system in NFS Version 4, see “Unsharing and Resharing a File System in NFS
Version 4” on page 29.
NFS Version 4 servers use a pseudo file system to provide clients with access to exported
objects on the server. For more information about pseudo file system, see “File System
Namespace in NFS Version 4” on page 29. NFS Version 4 supports volatile file handles.
For more information, see “Volatile File Handles in NFS Version 4” on page 32.
Delegation, a technique by which the server delegates the management of a file to a client,
is supported on both the client and the server. For example, the server could grant either a
read delegation or a write delegation to a client. For more information about delegation, see
“Delegation in NFS Version 4” on page 35.
NFS Version 4 does not support LIPKEY/SPKM security.
Also, NFS Version 4 does not use the following daemons:
■
lockd
■
nfslogd
■
statd
Chapter 1 • About Network File Systems
17
Features of the NFS Service
For a complete list of the features in NFS Version 4, see “Features in NFS Version
4” on page 28.
For information about setting up the NFS services, see “Setting Up the NFS
Service” on page 81.
Controlling NFS Versions
The SMF repository includes parameters to control the NFS protocols that are used by both the
client and the server. For example, you can use parameters to manage version negotiation. For
more information about the client and server parameters, see “NFS Daemons” on page 160.
For more information about the parameter values for NFS daemons, see the nfs(4) man page.
NFS ACL Support
Access control list (ACL) provides a mechanism to set file access permissions instead of using
the standard UNIX file permissions. NFS ACL support provides a method of changing and
viewing ACL entries from an Oracle Solaris NFS client to an Oracle Solaris NFS server.
The NFS Version 2 and Version 3 implementations support the old POSIX-draft style ACLs.
POSIX-draft ACLs are natively supported by UFS. For more information about POSIX-draft
ACLs, see “Using Access Control Lists to Protect UFS Files” in Securing Files and Verifying
File Integrity in Oracle Solaris 11.3.
The NFS Version 4 protocol supports NFS Version 4 style ACLs. NFS Version 4 ACLs are
natively supported by Oracle Solaris ZFS. You must use ZFS as the underlying file system
on the NFS Version 4 server for full featured NFS Version 4 ACL functionality. NFS Version
4 ACLs have a rich set of inheritance properties, as well as a set of permission bits beyond
the standard read, write, and execute. For more information about using ACLs to protect ZFS
files, see “Setting ACLs on ZFS Files” in Securing Files and Verifying File Integrity in Oracle
Solaris 11.3. For more information about support for ACLs in NFS Version 4, see “ACLs and
nfsmapid in NFS Version 4” on page 37.
NFS Over TCP
The default transport protocol for the NFS protocol is TCP (Transmission Control Protocol).
TCP helps performance on slow networks and wide area networks. TCP also provides
congestion control and error recovery. NFS over TCP works with the NFS Version 2, NFS
Version 3, and NFS Version 4 protocols.
18
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Features of the NFS Service
Note - If InfiniBand hardware is available on the system, the default transport protocol changes
from TCP to the Remote Direct Memory Access (RDMA) protocol. For more information, see
“Overview of NFS Over RDMA” on page 19 and “NFS Over RDMA” on page 26.
Note that, if you use the proto=tcp mount option, NFS mounts are forced to use TCP only.
NFS Over UDP
Starting with the Oracle Solaris 11 release, the NFS client uses only one UDP (User Datagram
Protocol) reserved port, which is configurable. The system can be configured to use more than
one port to increase system performance. This capability mirrors NFS over TCP support, which
has been configurable in this way since its inception. For more information about tuning the
NFS environment, see Oracle Solaris 11.3 Tunable Parameters Reference Manual.
Overview of NFS Over RDMA
If InfiniBand hardware is available on the system, the default transport protocol changes from
TCP to the RDMA protocol. The RDMA protocol is a technology for memory-to-memory
transfer of data over high-speed networks. Specifically, RDMA provides remote data transfer
directly to and from memory without CPU intervention. To provide this capability, RDMA
combines the interconnect I/O technology of InfiniBand with the Oracle Solaris OS. However,
if you use the proto=tcp mount option, NFS mounts are forced to use TCP only. For more
information about using the RDMA protocol for NFS, see “NFS Over RDMA” on page 26.
Network Lock Manager and NFS
The Network Lock Manager provides UNIX record locking for any files being shared over
NFS. The locking mechanism enables clients to synchronize their I/O requests with other
clients, ensuring data integrity.
Note - The Network Lock Manager is used only for NFS Version 2 and NFS Version 3 mounts.
File locking is built into the NFS Version 4 protocol.
NFS Large File Support
The NFS Version 3 protocol can handle files that are larger than 2 Gbytes, but the NFS Version
2 protocol cannot.
Chapter 1 • About Network File Systems
19
Features of the NFS Service
NFS Client Failover
Dynamic failover of read-only file systems provide a high level of availability for read-only
resources that are already replicated, such as man pages, other documentation, and shared
binaries. Failover can occur any time after the file system is mounted. Manual mounts can
now list multiple replicas, much like the automounter in previous releases. The automounter
has not changed, except that failover no longer waits until the file system is remounted. For
more information, see “How to Use Client-Side Failover” on page 77 and “Client-Side
Failover” on page 41.
Kerberos Support for the NFS Service
The NFS service supports Kerberos Version 5 authentication, integrity, and privacy when
you configure NFS clients and servers to support Kerberos. You can use the mount and share
command-line options when you use Kerberos for secure authentication. For information about
Kerberos Version 5 authentication, see “Configuring Kerberos NFS Servers” in Managing
Kerberos and Other Authentication Services in Oracle Solaris 11.3.
WebNFS Support
WebNFS provides the capability to make a file system on the Internet accessible through
firewalls. This capability uses an extension to the NFS protocol. One advantage of using the
WebNFS™ protocol for Internet access is its reliability. The service is built as an extension
of the NFS Version 3 and Version 2 protocol. Additionally, WebNFS enables you to share
files without the administrative overhead of an anonymous ftp site. For more information
about WebNFS, see “Security Negotiation for the WebNFS Service” on page 21 and
“Administering WebNFS” on page 87.
Note - The NFS Version 4 protocol is preferred over the WebNFS service. NFS version 4 fully
integrates all the security negotiation that was added to the MOUNT protocol and the WebNFS
service.
RPCSEC_GSS Security Flavor
A security flavor called RPCSEC_GSS is supported in the Solaris 7 release. This flavor uses
the standard GSS-API interfaces to provide authentication, integrity, and privacy, as well as
20
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Features of the NFS Service
enabling support of multiple security mechanisms. For more information about support of
Kerberos V5 authentication, see “Kerberos Support for the NFS Service” on page 20. For
more information about GSS-API, see Developer’s Guide to Oracle Solaris 11 Security.
Extensions for NFS Mounting
The NFS service provides extensions to the mount and automountd commands in Oracle
Solaris. These extensions enable the mount request to use the public file handle instead of the
MOUNT protocol. The WebNFS service uses the MOUNT protocol as the access method.
By using the public file handle, the mount can occur through a firewall. As there are fewer
transactions between the server and the client, the mount occurs faster.
The extensions also enable NFS URLs to be used instead of the standard path name. Also, you
can use the public option with the mount command and the automounter maps to force the
use of the public file handle. For more information about the WebNFS service, see “WebNFS
Support” on page 20.
Security Negotiation for the WebNFS Service
The NFS service enables a WebNFS client to negotiate a security mechanism with an NFS
server. WebNFS client uses a protocol to negotiate a security mechanism with an NFS server.
This protocol enables you to use secure transactions with the WebNFS service. For more
information about security negotiation for WebNFS, see “How WebNFS Security Negotiation
Works” on page 44.
NFS Server Logging
Note - NFS Version 4 does not support the server logging feature.
NFS server logging enables an NFS server to provide a record of file operations that have been
performed on its file systems. The record includes information about which file was accessed,
when the file was accessed, and who accessed the file. You can specify the location of the logs
that contain this information through a set of configuration options. You can also use these
options to select the operations to be logged. The NFS server logging feature is particularly
useful for sites that make anonymous FTP archives available to NFS and WebNFS clients. For
more information, see “How to Enable NFS Server Logging” on page 73.
Chapter 1 • About Network File Systems
21
Significant Changes in the Oracle Solaris 11 Release
Autofs Features
Autofs works with file systems that are specified in the local namespace. This information can
be maintained in LDAP, NIS (Network Information Service), or local files. Autofs supports the
following features:
■
A fully multithreaded version of the automountd feature capability makes autofs reliable.
This feature enables concurrent servicing of multiple mounts, which prevents the service
from hanging if a server is unavailable.
■
The automountd feature also provides on-demand mounting. Only the top file system is
mounted. Other file systems that are related to this mount point are mounted when needed.
■
The autofs service supports the "browsability" of indirect maps. This support enables a
user to see which directories could be mounted without having to actually mount each file
system. A -nobrowse option ensures that large file systems, such as /net and /home, are not
automatically browsable. Also, you can turn off autofs browsability on each client by using
the -n option with the automount command. For more information about different methods
to disable autofs browsability, see “Disabling Autofs Browsability” on page 107.
Significant Changes in the Oracle Solaris 11 Release
The Oracle Solaris 11 release includes the following enhancements:
■
■
■
■
22
A new property, nfs_props/showmount_info, has been added to the /network/nfs/
server:default service. This property controls the amount of information that the
showmount command displays to remote clients. For more information about the
nfs_props/showmount_info property, see the showmount(1M) man page.
Support for the Federated File System (FedFS) referrals has been added. This feature
enables referral information for several servers to be centralized in LDAP. For more
information about FedFS referrals, see “Administering FedFS” on page 91.
The configuration properties that used to be set by editing the /etc/default/autofs
and /etc/default/nfs files can now be set in the Service Management Facility (SMF)
repository. For more information about the new SMF properties and the daemons using the
new SMF properties, see “NFS Daemons” on page 160.
The NFS service provides support for mirror mounts. Mirror mounts enable an NFS Version
4 client to traverse shared file system mount points in the server namespace. For NFS
Version 4 mounts, the automounter performs a mount of the server namespace root and
relies on mirror mounts to access its file systems. The main advantage that mirror mounts
offer over the automounter is that mounting a file system using mirror mounts does not
require the overhead associated with administering automount maps. Mirror mounts provide
the following features:
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Significant Changes in the Oracle Solaris 11 Release
■
■
■
Namespace changes are immediately visible to all clients.
New shared file systems are discovered instantly and mounted automatically.
File systems unmount automatically after a designated inactivity period.
For more information about mirror mounts, see:
“How to Mount All File Systems From a Server” on page 77
■ “How Mirror Mounts Work” on page 49
NFS referrals have been added to the NFS service. Referrals are server-based redirections
that an NFS Version 4 client can follow to find a file system. The NFS server supports
referrals created by the nfsref command. The NFS Version 4 client follows these referrals
to mount the file system from the actual location. The creation of referrals replaces the
editing of the automounter map. NFS referrals provide these features:
■
■
■
■
■
All of the features of mirror mounts
Automounter-like functionality without any dependence on the automounter
No setup required on either the client or server
For more information about NFS referrals, see:
■
■
“Administering NFS Referrals” on page 90
“How NFS Referrals Work” on page 50
nfsref(1M) man page
The ability to mount the per-DNS-domain root of a FedFS namespace has been added. This
mount point can be used with NFS referrals to bridge from one file server to another file
server, building an arbitrarily large namespace. For more information about FedFS domain
root, see:
■
■
■
■
■
“Set Up a DNS Record for a FedFS Server” on page 91
■
“Mount Point /nfs4” on page 55
The sharectl utility enables you to configure and manage file sharing protocols, such as
NFS. For example, this utility enables you to set client and server operational properties,
display property values for a specific protocol, and obtain the status of a protocol. For more
information, see the sharectl(1M) man page.
The ability to restrict NFS service to clients which use reserved ports, that is port numbers
below 1024, has been added. This affects file systems shared with AUTH_SYS. This can
be set for all shares by using the resvport setting with the sharectl command, or for
individual file systems by using the resvport share option.
Chapter 1 • About Network File Systems
23
24
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
♦ ♦ ♦
2
C H A P T E R
2
Network File System Features
This chapter describes the relationship of Remote Direct Memory Access (RDMA) protocol to
other transport protocols. RDMA is the default transport for NFS. This chapter also describes
how the NFS service works, which includes version negotiation and the features introduced in
NFS Version 4 for file sharing.
This chapter contains the following topics:
■
■
■
■
■
■
■
“NFS Over RDMA” on page 26
“How the NFS Service Works” on page 25
“How Mirror Mounts Work” on page 49
“How NFS Referrals Work” on page 50
“Autofs Maps” on page 53
“How Autofs Works” on page 51
“Autofs Reference” on page 69
Note - If your system has zones enabled and you want to use this feature in a non-global zone,
see Introduction to Oracle Solaris Zones.
How the NFS Service Works
The following sections describe some of the complex functions of the NFS software. Some of
the feature descriptions in this section are exclusive to NFS Version 4.
■
■
■
■
■
“Version Negotiation in NFS” on page 28
“Features in NFS Version 4” on page 28
“UDP and TCP Negotiation” on page 38
“File Transfer Size Negotiation” on page 39
“How File Systems Are Mounted in NFS Version 3” on page 39
Chapter 2 • Network File System Features
25
How the NFS Service Works
■
“Effects of the -public Option and NFS URLs When Mounting” on page 40
■
“Client-Side Failover” on page 41
“How NFS Server Logging Works” on page 43
“How the WebNFS Service Works” on page 43
■
■
■
■
■
“WebNFS Limitations With Web Browser Use” on page 45
“Secure NFS Systems” on page 45
“Secure RPC” on page 46
Note - If your system has zones enabled and you want to use this feature in a non-global zone,
see Introduction to Oracle Solaris Zones.
NFS Over RDMA
Starting with the Oracle Solaris 11.1 release, the default transport for NFS is the Remote Direct
Memory Access (RDMA) protocol. This protocol provides memory-to-memory transfer of data
over high-speed networks. Specifically, RDMA provides remote data transfer directly to and
from memory without CPU intervention. RDMA also provides direct data placement, which
eliminates data copies and therefore further eliminates CPU intervention. Thus, RDMA frees
up not only the host CPU, but also reduces contention for the host memory and I/O buses. To
provide this capability, RDMA combines the interconnect I/O technology of InfiniBand, which
you can use on both SPARC and x86 platforms, with the Oracle Solaris operating system. The
following figure shows the relationship of RDMA to other protocols, such as UDP and TCP.
26
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
FIGURE 1
Relationship of RDMA to Other Protocols
Because RDMA is the default transport protocol for NFS, no special share or mount options are
required to use RDMA on a client or server. The existing automounter maps, vfstab and file
system shares, work with the RDMA transport. NFS mounts over the RDMA transport occur
transparently when InfiniBand connectivity exists between the client and the server. InfiniBand
connectivity feature works on both SPARC and x86 platforms. If the RDMA transport is not
available on both the client and the server, the TCP transport is the initial fallback, followed by
UDP if TCP is unavailable. However, if you use the proto=rdma mount option, NFS mounts are
forced to use RDMA only.
To specify the use of only TCP and UDP, you can use the proto=tcp/udp mount option. This
option disables RDMA on an NFS client. For more information about NFS mount options, see
the mount_nfs(1M) and mount(1M) man pages.
Chapter 2 • Network File System Features
27
How the NFS Service Works
Note - RDMA for InfiniBand uses the IP addressing format and the IP lookup infrastructure
to specify peers. However, because RDMA is a separate protocol stack, it does not fully
implement all IP semantics. For example, RDMA does not use IP addressing to communicate
with peers. Therefore, RDMA might bypass configurations for various security policies that
are based on IP addresses. However, the NFS and RPC administrative policies, such as mount
restrictions and secure RPC, are not bypassed.
Version Negotiation in NFS
The NFS initiation process includes negotiating the protocol version levels for servers and
clients. If you do not specify the version level, then the best level is selected by default. For
example, if both the client and the server can support NFS Version 3, then that is used. If the
client or the server can only support NFS Version 2, then that is used.
You can set the client_versmin, client_versmax, server_versmin, and server_versmax
parameters by using the sharectl command. Your specified minimum and maximum values
for the server and the client replace the default values for these parameters. For both the client
and the server, the default minimum value is 2 and the default maximum value is 4. To find the
version supported by the server, the NFS client begins with the value for client_versmax and
continues to try each version until reaching the version value for client_versmin. As soon
as the supported version is found, the process terminates. For example, if client_versmax=4
and client_versmin=2, then the client attempts NFS Version 4 first, then NFS Version 3, and
finally NFS Version 2. If client_versmax and client_versmax are set to the same value, then
the client always uses this version and does not attempt any other version. If the server does not
offer this version, the mount fails.
Note - You can override the values that are determined by the version negotiation in NFS by
using the vers option with the mount command. For more information about available options
for the mount command, see the mount_nfs(1M) man page.
For information about setting up the NFS service, see “Setting Up the NFS
Service” on page 81.
Features in NFS Version 4
This section provides descriptions of the features that were introduced in NFS Version 4:
■
28
“Unsharing and Resharing a File System in NFS Version 4” on page 29
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
■
■
■
“File System Namespace in NFS Version 4” on page 29
“Volatile File Handles in NFS Version 4” on page 32
“Client Recovery in NFS Version 4” on page 33
■
“OPEN Share Support in NFS Version 4” on page 34
“Delegation in NFS Version 4” on page 35
■
“ACLs and nfsmapid in NFS Version 4” on page 37
■
Note - Starting with the Oracle Solaris 10 release, NFS Version 4 does not support the LIPKEY/
SPKM security flavor. Also, NFS Version 4 does not use the mountd, nfslogd, and statd
daemons.
For information about setting up NFS services, see “Setting Up the NFS
Service” on page 81.
Unsharing and Resharing a File System in NFS Version 4
With both NFS Version 3 and NFS Version 4, if a client attempts to access a file system that has
been unshared, the server responds with an error code. However, with NFS Version 3, the server
maintains any locks that the clients had obtained before the file system was unshared. Thus,
when the file system is reshared, NFS Version 3 clients can access the file system as though that
file system had never been unshared.
With NFS Version 4, when a file system is unshared, all the state information for any open files
or file locks in that file system is destroyed. If the client attempts to access these files or locks,
the client receives an error. This error is usually reported as an I/O error to the application.
However, resharing a currently shared file system to change options does not destroy any of the
state information on the server.
For information about client recovery in NFS Version 4, see “Client Recovery in NFS Version
4” on page 33. For information about available options for the unshare command, see the
unshare_nfs(1M) man page.
File System Namespace in NFS Version 4
NFS Version 4 servers create and maintain a pseudo file system that provides NFS clients
with seamless access to all exported objects on the server. Prior to NFS Version 4, the pseudo
file system did not exist. NFS clients were forced to mount each shared server file system for
access.
Chapter 2 • Network File System Features
29
How the NFS Service Works
A pseudo file system is a structure that contains only directories and is created by the server.
The pseudo file system permits a client to browse the hierarchy of exported file systems. Thus,
the client's view of the pseudo file system is limited to paths that lead to exported file systems.
Previous versions of NFS did not permit a client to traverse server file systems without
mounting each file system. However, in NFS Version 4, the server namespace does the
following:
■
■
30
Restricts the client's file system view to directories that lead to server exports.
Provides clients with seamless access to server exports without requiring the client to mount
each underlying file system. However, different operating systems might require the client
to mount each server file system.
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
FIGURE 2
Views of the Server File System and the Client File System in NFS Version 4
Chapter 2 • Network File System Features
31
How the NFS Service Works
In the example shown in the figure, the client cannot see the payroll directory and the nfs4x
directory because these directories are not exported and do not lead to exported directories.
However, the local directory is visible to the client because local is an exported directory.
The projects directory is visible to the client because projects leads to the exported directory,
nfs4. Thus, portions of the server namespace that are not explicitly exported are bridged with
a pseudo file system that views only the exported directories and those directories that lead to
server exports.
Volatile File Handles in NFS Version 4
File handles are created on the NFS server and contain information that uniquely identifies files
and directories. In NFS Version 2 and NFS Version 3, the NFS server returned persistent file
handles. Thus, the NFS client could guarantee that the NFS server would generate a file handle
that always referred to the same file. For example:
■
■
■
If a file was deleted and replaced with a file of the same name, the server would generate a
new file handle for the new file. If the client used the old file handle, the server would return
an error that the file handle was stale.
If a file was renamed, the file handle would remain the same.
If the server was rebooted, the file handles would remain the same.
Thus, when the server received a request from a client that included a file handle, the resolution
was straightforward and the file handle always referred to the correct file.
The method of using persistent file handles for identifying files and directories for NFS
operations was fine for most UNIX-based servers. However, the method could not be
implemented on servers that relied on other methods of identification, such as a file's path
name. To resolve this problem, the NFS Version 4 protocol permits a server to declare that its
file handles are volatile. If the file handle does change, the client must find the new file handle.
Like NFS Versions 2 and NFS Version 3 servers, the Oracle Solaris NFS Version 4 server
always provides persistent file handles. However, Oracle Solaris NFS Version 4 clients that
access non Oracle Solaris NFS Version 4 servers must support volatile file handles if the server
uses them. Specifically, when the server communicates to the client that the file handle is
volatile, the client must cache the mapping between the path name and file handle. The client
uses the volatile file handle until it expires. On expiration, the client does the following:
■
■
■
Flushes the cached information that refers to that file handle
Searches for that file's new file handle
Retries the operation
Note - The server always communicates to the client which file handles are persistent and
which file handles are volatile.
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
Volatile file handles might expire in any of these situations:
■
■
■
■
When you close a file
When the file handle's file system migrates
When a client renames a file
When the server reboots
If the client is unable to find the new file handle, an error message is logged in the syslog file.
Further attempts to access this file fail with an I/O error.
Client Recovery in NFS Version 4
The NFS Version 4 protocol is a stateful protocol. Both the NFS client and the NFS server
maintain current information about the open files and file locks.
When a server crashes and is rebooted, the server loses its state. The client detects that the
server has rebooted and begins the process of helping the server re-establish the open and lock
states that existed prior to the failure. This process is known as client recovery because the
client directs the process.
When the client detects that the server has rebooted, the client immediately suspends its current
activity and begins the process of client recovery. When the recovery process starts, a message
such as the following is displayed in the system error log /var/adm/messages:
NOTICE: Starting recovery server server-name
During the recovery process, the client sends the server information about the client's previous
state. However, during this period, the client does not send any new requests to the server. Any
new requests to open files or set file locks must wait for the server to complete its recovery
process before proceeding.
When the client recovery process is complete, the following message is displayed in the system
error log /var/adm/messages:
NOTICE: Recovery done for server server-name
At this point, the client has successfully completed sending its state information to the server.
However, even though the client has completed this process, other clients might not have done
so. Therefore, for a period of time, known as the grace period, the server does not accept any
open or lock requests to enable all clients to complete their recovery.
During the grace period, if the client attempts to open any new files or establish any new locks,
the server denies the request with the GRACE error code. Upon receiving this error, the client
must wait for the grace period to end and then resend the request to the server. During the grace
period, the following message is displayed:
Chapter 2 • Network File System Features
33
How the NFS Service Works
NFS server recovering
During the grace period, the commands that do not open files or set file locks can proceed. For
example, the commands ls and cd do not open a file or set a file lock, these commands are not
suspended. However, a command such as cat, which opens a file, would be suspended until the
grace period ends.
When the grace period has ended, the following message is displayed:
NFS server recovery ok.
The client can now send new open and lock requests to the server.
Client recovery can fail for a variety of reasons. For example, if a network partition exists after
the server reboots, the client might not be able to re-establish its state with the server before the
grace period ends. When the grace period has ended, the server does not permit the client to reestablish its state because new state operations could create conflicts. For example, a new file
lock might conflict with an old file lock that the client is trying to recover. When such situations
occur, the server returns the NO_GRACE error code to the client.
If the recovery of an open operation for a file fails, the client marks the file as unusable and the
following message is displayed:
WARNING: The following NFS file could not be recovered and was marked dead
(can't reopen: NFS status n): file : filename
If re-establishing a file lock during recovery fails, the following error message is displayed:
NOTICE: nfs4_send_siglost: pid process-ID lost
lock on server server-name
In this situation, the SIGLOST signal is posted to the process. The default action for the SIGLOST
signal is to terminate the process.
To recover from this state, you must restart any applications that had files open at the time of
the failure. Some processes that did not reopen the file could receive I/O errors. Other processes
that did reopen the file, or performed the open operation after the recovery failure, can access
the file without any problems.
Thus, some processes can access a particular file while other processes cannot.
OPEN Share Support in NFS Version 4
The NFS Version 4 protocol provides several file-sharing modes that the client can use to
control file access by other clients. A client can specify the following:
■
34
DENY_NONE mode permits other clients read and write access to a file.
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
■
DENY_READ mode denies other clients read access to a file.
■
DENY_WRITE mode denies other clients write access to a file.
■
DENY_BOTH mode denies other clients read and write access to a file.
The Oracle Solaris NFS Version 4 server fully implements these file-sharing modes. Therefore,
if a client attempts to open a file in a way that conflicts with the current share mode, the server
denies the attempt by failing the operation. When such attempts fail with the initiation of the
open or create operations, the NFS Version 4 client receives a protocol error. This error is
mapped to the application error EACCES.
Even though the protocol provides several sharing modes, the open operation in Oracle Solaris
does not offer multiple sharing modes. When opening a file, an Oracle Solaris NFS Version 4
client can only use the DENY_NONE mode.
Note - Even though the fcntl system call has an F_SHARE command to control file sharing, the
fcntl commands cannot be implemented correctly with NFS Version 4. If you use these fcntl
commands on an NFS Version 4 client, the client returns the EAGAIN error to the application.
Delegation in NFS Version 4
NFS Version 4 provides both client support and server support for delegation. Delegation
is a technique by which the NFS server delegates the management of a file to a NFS client.
For example, the server could grant either a read delegation or a write delegation to a client.
Because read delegations do not conflict with each other, they can be granted to multiple
clients at the same time. A write delegation can be granted to only one client because a write
delegation conflicts with any file access by any other client. While holding a write delegation,
the client does not send various operations to the server because the client is guaranteed
exclusive access to a file. Similarly, the client does not send various operations to the server
while holding a read delegation. Because the server guarantees that no client can open the file in
write mode.
The effect of delegation is to greatly reduce the interactions between the server and the client
for delegated files. Therefore, network traffic is reduced, and performance on the client and the
server is improved. However, the degree of performance improvement depends on the kind of
file interaction used by an application and the amount of network and server congestion.
A client does not request a delegation. The decision about whether to grant a delegation is made
entirely by the server based on the access patterns for a file. If a file has been recently accessed
in write mode by several different clients, the server might not grant a delegation because this
access pattern indicates the potential for future conflicts.
Chapter 2 • Network File System Features
35
How the NFS Service Works
A conflict occurs when a client accesses a file in a manner that is inconsistent with the
delegations that are currently granted for that file. For example, if a client holds a write
delegation on a file and a second client opens that file for read or write access, the server recalls
the first client's write delegation. Similarly, if a client holds a read delegation and another client
opens the same file for writing, the server recalls the read delegation. In both situations, the
second client is not granted a delegation because a conflict now exists.
When a conflict occurs, the NFS server uses a callback mechanism to contact the NFS client
that currently holds the delegation. Upon receiving this callback, the client sends the file's
updated state to the server and returns the delegation. If the client fails to respond to the recall,
the server revokes the delegation. In such instances, the server rejects all operations from the
client for this file, and the client reports the requested operations as failures. Generally, these
failures are reported to the application as I/O errors. To recover from these errors, the file must
be closed and then reopened. Failures from revoked delegations can occur when a network
partition exists between the client and the server while the client holds a delegation.
Note that one server cannot resolve access conflicts for a file that is stored on another server.
Thus, an NFS server only resolves conflicts for files that it stores. Furthermore, in response to
conflicts that are caused by clients that are running various versions of NFS, an NFS server can
initiate recalls only to the client that is running NFS Version 4. An NFS server cannot initiate
recalls for clients that are running earlier versions of NFS.
The process for detecting conflicts varies. For example, unlike NFS Version 4, because NFS
Version 2 and NFS Version 3 do not have an open procedure, the conflict is detected only after
the client attempts to read, write, or lock a file. The server's response to these conflicts varies
also. For example:
■
■
For NFS Version 3, the server returns the JUKEBOX error, which causes the client to halt the
access request and try again later. The client displays the message File unavailable.
For NFS Version 2, because an equivalent of the JUKEBOX error does not exist, the server
makes no response, which causes the client to wait and then try again. The client displays
the message NFS server not responding.
The error messages clear when the delegation conflict is resolved.
By default, NFS server delegation is enabled. You can disable delegation by setting the
server_delegation parameter to off.
$ sharectl set -p server_delegation=off nfs
No keywords are required for NFS client delegation. The NFS Version 4 callback daemon,
nfs4cbd, provides the callback service on the client. This daemon is started automatically
whenever a mount for NFS Version 4 is enabled. By default, the client provides the necessary
callback information to the server for all Internet transports that are listed in the /etc/
netconfig system file. If the client is enabled for IPv6 and if the IPv6 address for the client's
name can be determined, then the callback daemon accepts IPv6 connections.
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
The callback daemon uses a transient program number and a dynamically assigned port number.
This information is provided to the server, and the server tests the callback path before granting
any delegations. If the callback path does not test successfully, the server does not grant
delegations, which is the only externally visible behavior.
Because callback information is embedded within an NFS Version 4 request, the server is
unable to contact the client through a network device that uses Network Address Translation
(NAT). Also, the callback daemon uses a dynamic port number. Therefore, the server might not
be able to traverse a firewall, even if that firewall enables normal NFS traffic on port 2049. In
such situations, the server does not grant delegations.
ACLs and nfsmapid in NFS Version 4
An access control list (ACL) provides file security by enabling the owner of a file to define
file permissions for the file owner, the group, and other specific users and groups. On ZFS file
systems, you can set ACLs on the NFS server and the NFS client by using the chmod command.
For UFS file systems, you can use the setfacl command. For more information, see the
chmod(1) and setfacl(1) man pages. In NFS Version 4, the ID mapper, nfsmapid, is used to
map user IDs or group IDs in ACL entries on a server to user IDs or group IDs in ACL entries
on a client. The reverse is also true: The user and group IDs in the ACL entries must exist on
both the client and the server.
For more information about ACLs and nfsmapid, see the following:
■
■
“Setting ACLs on ZFS Files” in Securing Files and Verifying File Integrity in Oracle
Solaris 11.3
“NFS Daemons” on page 160
ID Mapping Problems
The following situations can cause ID mapping to fail:
■
■
If a user or group that exists in an ACL entry on the server cannot be mapped to a valid user
or group on the client, the user can read the ACL but some of the users or groups will be
shown as unknown.
For example, in this situation when you issue the ls -lv or ls -lV command, some of the
ACL entries will have the group or user displayed as unknown.
If the user ID or group ID in any ACL entry that is set on the client cannot be mapped to
a valid user ID or group ID on the server, the setfacl and chmod commands can fail and
return the Permission denied error message.
Chapter 2 • Network File System Features
37
How the NFS Service Works
■
If the client and server have mismatched nfsmapid_domain values, ID mapping fails. For
more information, see “NFS Daemons” on page 160.
To avoid ID mapping problems, do the following:
■
■
Make sure that the value for nfsmapid_domain is set correctly. The currently selected
NFSv4 domain is available in the /var/run/nfs4_domain file.
Make sure that all user IDs and group IDs in the ACL entries exist on both the NFS Version
4 client and server.
Checking for Unmapped User IDs or Group IDs
To determine whether any user or group cannot be mapped on the NFS server or client, use the
following script:
#! /usr/sbin/dtrace -Fs
sdt:::nfs4-acl-nobody
{
printf("validate_idmapping: (%s) in the ACL could not be mapped!",
stringof(arg0));
}
Note - The probe name that is used in this script is an interface that could change in the future.
For more information, see “Stability Levels” in Oracle Solaris 11.3 DTrace (Dynamic Tracing)
Guide.
UDP and TCP Negotiation
In NFS Version 2 and NFS Version 3, negotiation for transport protocol happens at mount time.
During initiation, the transport protocol is also negotiated. By default, the first connectionoriented transport that is supported on both the NFS client and the NFS server is selected. If
this selection does not succeed, the first available connectionless transport protocol is used.
The transport protocols that are supported on a system are listed in the /etc/netconfig file.
TCP is the connection-oriented transport protocol that is supported by the release. UDP is the
connectionless transport protocol.
When both the NFS protocol version and the transport protocol are determined by negotiation,
the NFS protocol version is given precedence over the transport protocol. The NFS Version 3
protocol that uses UDP is given higher precedence than the NFS Version 2 protocol that is using
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
TCP. You can manually select both the NFS protocol version and the transport protocol with the
mount command. For information about the NFS specific options for the mount command, see
the mount_nfs(1M) man page. Under most conditions, allow the negotiation to select the best
options.
File Transfer Size Negotiation
The file transfer size establishes the size of the buffers that are used when data is transferred
between the NFS client and the NFS server. In general, larger transfer sizes are better. The NFS
Version 3 protocol has an unlimited transfer size. Although the client can bid a smaller transfer
size at mount time, under most conditions, this bid is not necessary.
The transfer size is not negotiated with systems that use the NFS Version 2 protocol. The
maximum transfer size is set to 8 KB.
You can use the -rsize and -wsize options to manually set the transfer size with the mount
command. You might need to reduce the transfer size for some system clients. Also, you can
increase the transfer size if the NFS server is configured to use larger transfer sizes.
Note - Starting with the Oracle Solaris 10 release, restrictions on wire transfer sizes have been
relaxed. The transfer size is based on the capabilities of the underlying transport. For example,
the NFS transfer limit for UDP is still 32 KB. However, because TCP is a streaming protocol
without the datagram limits of UDP, maximum transfer sizes over TCP have been increased to 1
MB.
How File Systems Are Mounted in NFS Version 3
The information in this section applies to NFS Version 3 mounts. The NFS Version 4 mount
process does not include the portmap service or the MOUNT protocol.
When an NFS client attempts to mount a file system from an NFS server, the client must obtain
a file handle from the server. The file handle must correspond to the file system. This process
requires that several transactions occur between the client and the server. In this example, the
NFS client is attempting to mount /home/user from the NFS server. A snoop trace for this
transaction follows:
client -> server PORTMAP C GETPORT prog=100005 (MOUNT) vers=3 proto=UDP
server -> client PORTMAP R GETPORT port=33482
Chapter 2 • Network File System Features
39
How the NFS Service Works
client
server
client
server
client
server
client
server
client
server
client
server
->
->
->
->
->
->
->
->
->
->
->
->
server
client
server
client
server
client
server
client
server
client
server
client
MOUNT3 C Null
MOUNT3 R Null
MOUNT3 C Mount /export/home9/user
MOUNT3 R Mount OK FH=9000 Auth=unix
PORTMAP C GETPORT prog=100003 (NFS) vers=3 proto=TCP
PORTMAP R GETPORT port=2049
NFS C NULL3
NFS R NULL3
NFS C FSINFO3 FH=9000
NFS R FSINFO3 OK
NFS C GETATTR3 FH=9000
NFS R GETATTR3 OK
In this trace, the NFS client first requests the mount port number from the portmap service on
the NFS server. After the client receives the mount port number (33492), that number is used to
test the availability of the service on the server. After the client has determined that a service is
running on that port number, the client then makes a mount request. When the server responds
to this request, the server includes the file handle for the file system (9000) being mounted. The
client then sends a request for the NFS port number. When the client receives the number from
the server, the client tests the availability of the NFS service (nfsd). Also, the client requests
NFS information about the file system that uses the file handle.
In the following trace, the client is mounting the file system with the public option:
client
server
client
server
client
server
->
->
->
->
->
->
server
client
server
client
server
client
NFS
NFS
NFS
NFS
NFS
NFS
C
R
C
R
C
R
LOOKUP3 FH=0000 /export/home9/user
LOOKUP3 OK FH=9000
FSINFO3 FH=9000
FSINFO3 OK
GETATTR3 FH=9000
GETATTR3 OK
By using the default public file handle (which is 0000), all the transactions to obtain information
from the portmap service and to determine the NFS port number are skipped.
Note - NFS Version 4 provides support for volatile file handles. For more information, see
“Volatile File Handles in NFS Version 4” on page 32.
Effects of the -public Option and NFS URLs When
Mounting
Using the -public option can create conditions that cause a mount to fail. Adding an NFS URL
can also cause failures. The following list describes how a file system is mounted when you use
these options:
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
■
■
■
■
Public option with NFS URL – Use the public file handle. The mount fails if the public
file handle is not supported.
Public option with regular path – Use the public file handle. The mount fails if the public
file handle is not supported.
NFS URL only – Use the public file handle if this file handle is enabled on the NFS server.
If the mount fails when you use the public file handle, then try the mount with the MOUNT
protocol.
Regular path only – Do not use the public file handle. The MOUNT protocol is used.
Client-Side Failover
Failover is process of selecting a server from a list of servers that support a replicated file
system. Normally, the next server in the sorted list is used unless it fails to respond. By using
client-side failover, an NFS client can detect when multiple servers are making the same data
available and can switch to an alternative server when the current server is unavailable. This
switch is known as remapping. Through normal use, the clients store the path name for each
active file on a remote file system. During the remapping, these path names are evaluated to
locate the files on the new server.
The file system can become unavailable if one of the following conditions occurs:
■
■
■
If the file system is connected to a server that crashes
If the server is overloaded
If a network fault occurs
The failover under these conditions is normally transparent to the user. It can occur at any time
without disrupting the processes that are running on the client.
For failover to occur, the file systems must be mounted read-only. The file systems must be
identical for the failover to occur successfully. For information about identical file systems, see
“What Is a Replicated File System?” on page 42. A static file system or a file system that is
not changed often is the best candidate for failover.
You cannot use CacheFS and client-side failover on the same NFS mount. Extra information is
stored for each CacheFS file system. This information cannot be updated during failover, so you
can use only one of these two features when mounting a file system.
The number of replicas that must be established for every file system depends on many factors.
Ideally, you have a minimum of two servers. Each server supports multiple subnets. This setup
is better than having a unique server on each subnet. The process requires the checking of each
listed server. Therefore, if more servers are listed, each mount is slower.
Chapter 2 • Network File System Features
41
How the NFS Service Works
What Is a Replicated File System?
For the purposes of client-side failover, a file system can be called a replica when it is the same
size and has the same file size or file type as the original file system. Permissions, creation
dates, and other file attributes are not considered. If the file size or file types are different, the
remapping fails and the process hangs until the old server becomes available. In NFS Version
4, the behavior is different. For more information about client-side failover, see “Client-Side
Failover in NFS Version 4” on page 42.
You can maintain a replicated file system by using rsync, cpio, or another file transfer
mechanism. Because updating the replicated file systems causes inconsistency, for best results
consider these precautions:
■
■
■
■
Rename the old version of the file before installing a new version of the file.
Run the updates at night when client usage is low.
Keep the updates small.
Minimize the number of copies of the file.
Failover and NFS Locking
Some software packages require read locks on files. To prevent these products from breaking,
read locks on read-only file systems are allowed but are visible to the client side only. The locks
persist through a remapping because the server cannot detect the locks. Because the files should
not change, you do not need to lock the file on the server side.
Client-Side Failover in NFS Version 4
In NFS Version 4, if a replica cannot be established because the file sizes are different or the file
types are not the same, then the following happens:
1. The file is marked dead.
2. A warning is displayed.
3. The application that uses a file on the replicated mount receives a system call failure.
Note - If you restart the application and try again to access the file, you should be successful.
In NFS Version 4, you no longer receive replication errors for directories of different sizes. In
prior versions of NFS, this condition was treated as an error and would impede the remapping
process.
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
Furthermore, in NFS Version 4, if a directory read operation is unsuccessful, the operation is
performed by the next listed server. In previous versions of NFS, unsuccessful read operations
would cause the remapping to fail and the process to hang until the original server was
available.
How NFS Server Logging Works
Note - Server logging is not supported in NFS Version 4.
NFS server logging provides records of NFS reads and writes, as well as operations that modify
a file system. These records can be used to track access to information. In addition, the records
can provide a quantitative way to measure interest in the information.
When a file system with logging enabled is accessed, the kernel writes raw data into a buffer
file. This data includes the following:
■
■
■
■
■
Time stamp
Client IP address
UID of the requester
File handle of the file or directory object that is being accessed
Type of operation that occurred
The nfslogd daemon converts this raw data into ASCII records that are stored in log files.
During the conversion, the IP addresses are modified to host names and the UIDs are modified
to logins if the name service that is enabled can find matches. The file handles are also
converted into path names. To accomplish the conversion, the daemon tracks the file handles
and stores information in a separate file handle-to-path table. That way, the path does not have
to be identified again each time a file handle is accessed. Because no changes to the mappings
are made in the file handle-to-path table if nfslogd is disabled, you must keep the daemon
running.
How the WebNFS Service Works
The WebNFS service makes files in a directory available to clients by using a public file handle.
A file handle is an address that is generated by the kernel that identifies a file for NFS clients.
The public file handle has a predefined value, so the server does not need to generate a file
handle for the client. The ability to use this predefined file handle reduces network traffic by
eliminating the MOUNT protocol. This ability should also accelerate processes for the clients.
Chapter 2 • Network File System Features
43
How the NFS Service Works
By default, the public file handle on an NFS server is established on the root file system. This
default provides WebNFS access to any clients that already have mount privileges on the server.
You can change the public file handle to point to any file system by using the share command.
When the NFS client has the file handle for the file system, a LOOKUP is run to determine the
file handle for the file to be accessed. The NFS protocol allows the evaluation of only one
path name component at a time. Each additional level of directory hierarchy requires another
LOOKUP. A WebNFS server can evaluate an entire path name with a single multicomponent
lookup transaction when the LOOKUP is relative to the public file handle. Multicomponent lookup
enables the WebNFS server to deliver the file handle to the desired file without exchanging the
file handles for each directory level in the path name.
In addition, an NFS client can initiate concurrent downloads over a single TCP connection.
This connection provides quick access without the additional load on the server that is caused
by setting up multiple connections. Although web browser applications support concurrent
downloading of multiple files, each file has its own connection. By using one connection, the
WebNFS software reduces the overhead on the server.
If the final component in the path name is a symbolic link to another file system, the client can
access the file if the client already has access through normal NFS activities.
Normally, an NFS URL is evaluated relative to the public file handle. To change the evaluation
to be relative to the server's root file system, add an additional slash to the beginning of the
path. The following two NFS URLs are equivalent if the public file handle has been established
on the /export/ftp file system.
nfs://server/junk
nfs://server//export/ftp/junk
Note - The NFS Version 4 protocol is preferred over the WebNFS service. NFS Version 4 fully
integrates all the security negotiation that was added to the MOUNT protocol and the WebNFS
service.
How WebNFS Security Negotiation Works
The NFS service includes a protocol that enables a WebNFS client to negotiate a selected
security mechanism with a WebNFS server. The new protocol uses security negotiation
multicomponent lookup, which is an extension to the multicomponent lookup that was used in
earlier versions of the WebNFS protocol.
The WebNFS client initiates the process by making a regular multicomponent lookup request by
using the public file handle. Because the client has no knowledge of how the path is protected
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
by the server, the default security mechanism is used. If the default security mechanism is not
sufficient, the server replies with an AUTH_TOOWEAK error. The client needs to use a stronger
default mechanism.
When the client receives the AUTH_TOOWEAK error, the client sends a request to the server to
determine which security mechanisms are required. If the request succeeds, the server responds
with an array of security mechanisms that are required for the specified path. Depending on the
size of the array of security mechanisms, the client might have to make more requests to obtain
the complete array. If the server does not support WebNFS security negotiation, the request
fails.
After a successful request, the WebNFS client selects the first security mechanism from the
array that the client supports. The client then issues a regular multicomponent lookup request by
using the selected security mechanism to acquire the file handle. All subsequent NFS requests
are made by using the selected security mechanism and the file handle.
WebNFS Limitations With Web Browser Use
The WebNFS software does not support several functions that a web site that uses HTTP can
provide. These differences stem from the fact that the NFS server sends only the file, so any
special processing must be done on the client. If you need to have one web site configured for
both WebNFS and HTTP access, consider the following issues:
■
■
■
NFS browsing does not run CGI scripts. So, a file system with an active web site that uses
many CGI scripts might not be appropriate for NFS browsing.
Accessing these files in different file formats through an NFS URL starts an external viewer
if the file type can be determined by the file name. Because the WebNFS software does
not check inside the file to determine the file type, the only way to determine a file type
is by the file name extension. The browser should recognize any file name extension for a
standard MIME type.
NFS browsing cannot use server-side image maps but it can use client-side image maps
because the URLs are defined with the location. No additional response is required from the
document server.
Secure NFS Systems
The NFS environment is a powerful and convenient way to share file systems on a network
of different computer architectures and operating systems. However, the same features that
make sharing file systems through NFS operation convenient also pose some security problems.
Historically, most NFS implementations have used UNIX (or AUTH_SYS) authentication,
Chapter 2 • Network File System Features
45
How the NFS Service Works
but stronger authentication methods such as AUTH_DH have also been available. When using
UNIX authentication, an NFS server authenticates a file request by authenticating the computer
that makes the request but not the user. Therefore, an NFS client user can run su to become
superuser and impersonate the owner of a file. If DH authentication is used, the NFS server
authenticates the user, making this sort of impersonation much harder.
With root access and a knowledge of network programming, anyone can introduce arbitrary
data into the network and extract any data from the network. The most dangerous attacks
involve the introduction of data. An example is the impersonation of a user by generating the
right packets or by recording “conversations” and replaying them later. These attacks affect
data integrity. Attacks that involve passive eavesdropping, which is merely listening to network
traffic without impersonating anybody, are not as dangerous because data integrity is not
compromised. Users can protect the privacy of sensitive information by encrypting data that is
sent over the network.
A common approach to network security problems is to leave the solution to each application.
A better approach is to implement a standard authentication system at a level that covers all
applications.
The Oracle Solaris operating system includes an authentication system at the level of the RPC,
which is the mechanism on which the NFS operation is built. This system, known as Secure
RPC, greatly improves the security of network environments and provides additional security
to services such as the NFS system. An NFS system that uses the facilities that are provided by
Secure RPC is known as a Secure NFS system.
Secure RPC
Secure RPC is fundamental to the Secure NFS system. The goal of Secure RPC is to build a
system that is at minimum as secure as a time-sharing system. In a time-sharing system all
users share a single computer and users are authenticated through login passwords. With Data
Encryption Standard (DES) authentication, the same authentication process is completed. Users
can log in on any remote computer just as users can log in on a local terminal. The users' login
passwords are their assurance of network security. In a time-sharing environment, the system
administrator has an ethical obligation not to change a password to impersonate someone. In
Secure RPC, the network administrator is trusted not to alter entries in a database that stores
public keys.
An RPC authentication system uses credentials and verifiers. Using ID badges as an example,
the credential is what identifies a person: a name, address, and birthday. The verifier is the
photo that is attached to the badge. You can be sure that the badge has not been stolen by
checking the photo on the badge against the person who is carrying the badge. In RPC, the
client process sends both a credential and a verifier to the server with each RPC request. The
server sends back only a verifier because the client already “knows” the server's credentials.
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How the NFS Service Works
RPC's authentication is open ended, which means that a variety of authentication systems can
be plugged into it, such as UNIX, DH, and KERB.
When UNIX authentication is used by a network service, the credentials contain the client's host
name, UID, GID, and group-access list. However, because no verifier exists, a superuser could
falsify appropriate credentials by using commands such as su. Another problem is that UNIX
authentication assumes all computers on a network are UNIX computers. UNIX authentication
breaks down when applied to other operating systems in a heterogeneous network.
To overcome the problems of UNIX authentication, Secure RPC uses DH authentication.
Note - Although support for the Kerberos authentication system is no longer supplied as part of
Secure RPC, a server-side and client-side implementation is included in the release. For more
information about the implementation of Kerberos authentication, see Chapter 2, “Kerberos
on Oracle Solaris” in Managing Kerberos and Other Authentication Services in Oracle Solaris
11.3.
DH Authentication
DH authentication uses the Data Encryption Standard (DES) and Diffie-Hellman public-key
cryptography to authenticate both users and computers in the network. DES is a standard
encryption mechanism. Diffie-Hellman public-key cryptography is a cipher system that
involves two keys: one public and one secret. The public keys and secret keys are stored in the
namespace. NIS stores the keys in the public-key map. These maps contain the public key and
secret key for all potential users. For more information about how to set up the maps, see the
Working With Oracle Solaris 11.3 Directory and Naming Services: DNS and NIS.
The security of DH authentication is based on a sender's ability to encrypt the current time,
which the receiver can then decrypt and check against its own clock. The timestamp is
encrypted with DES. The two agents must agree on the current time, and sender and receiver
must be using the same encryption key.
If a network runs a time-synchronization program, the time on the NFS client and the NFS
server is synchronized automatically. If a time-synchronization program is not available,
timestamps can be computed by using the server's time instead of the network time. The client
asks the server for the time before starting the RPC session, then computes the time difference
between its own clock and the server's. This difference is used to offset the client's clock when
computing timestamps. If the client and server clocks become unsynchronized, the server
begins to reject the client's requests. The DH authentication system on the client resynchronizes
with the server.
The client and server arrive at the same encryption key by generating a random conversation
key, also known as the session key, and by using public-key cryptography to deduce a common
Chapter 2 • Network File System Features
47
How the NFS Service Works
key. The common key is a key that only the client and server are capable of deducing. The
conversation key is used to encrypt and decrypt the client's timestamp. The common key is used
to encrypt and decrypt the conversation key.
Using Secure RPC With NFS
Be aware of the following points if you plan to use Secure RPC:
■
■
■
48
If an NFS server crashes when no system administrator is available (after a power failure,
for example), all the secret keys that are stored on the system are deleted. No process can
access secure network services or mount an NFS file system. The important processes
during a reboot are usually run as root. Therefore, these processes would work if root's
secret key were stored away, but nobody is available to type the password that decrypts it.
keylogin -r allows root to store the clear secret key in /etc/.rootkey, which keyserv
reads.
Some systems boot in single-user mode, with a root login shell on the console and no
password prompt. Physical security is imperative in such cases.
Diskless computer booting is not totally secure. Somebody could impersonate the boot
server and boot a devious kernel that, for example, makes a record of the secret key on a
remote computer. The Secure NFS system provides protection only after the kernel and the
key server are running. Otherwise, no way exists to authenticate the replies that are given
by the boot server. This limitation could be a serious problem, but the limitation requires a
sophisticated attack using kernel source code. Also, the crime would leave evidence. If you
polled the network for boot servers, you would discover the devious boot server's location.
■
Most setuid programs are owned by root. If the secret key for root is stored in
/etc/.rootkey, these programs behave as they always have. If a setuid program is owned
by a user, however, the setuid program might not always work. For example, suppose that a
setuid program is owned by dave and dave has not logged into the computer since it booted.
The program would not be able to access secure network services.
■
If you log in to a remote computer (using login, rlogin, or telnet) and use keylogin to
gain access, you provide access to your account. Your secret key is passed to that computer's
key server, which then stores your secret key. This process is only a concern if you do not
trust the remote computer. If you have doubts, however, do not log in to a remote computer
if the remote computer requires a password. Instead, use the NFS environment to mount file
systems that are shared by the remote computer. As an alternative, you can use keylogout
to delete the secret key from the key server.
■
If a home directory is shared with the -o sec=dh option, remote logins can be a problem.
If the /etc/hosts.equiv or ~/.rhosts files are not set to prompt for a password, the login
succeeds. However, the users cannot access their home directories because no authentication
has occurred locally. If users are prompted for a password, they have access to their home
directories if the password matches the network password.
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How Mirror Mounts Work
How Mirror Mounts Work
The Oracle Solaris 11 release includes a new mounting facility called mirror mounts. Mirror
mounts allow an NFS Version 4 client to access files in a file system as soon as the file system
is shared on an NFS Version 4 server. The files can be accessed without the overhead of using
the mount command or updating autofs maps. In effect, after an NFS Version 4 file system is
mounted on a client, any other file systems from that server can also be mounted.
Generally, using the mirror mounts facility is optimal for your NFS Version 4 clients except
when you need to do the following:
■
■
Use a different hierarchy on the client than exists on the server
Use different mount options than those of the parent file system
Mounting a File System Using Mirror Mounts
If a file system is mounted on an NFS Version 4 client by using manual mounts or autofs, any
additional file systems that are added to the mounted file system can be mounted on the client
by using the mirror mount facility. The client requests access to the new file system with the
same mount options that were used on the parent directory. If the mount fails for any reason, the
normal NFS Version 4 security negotiations occur between the server and the client to adjust the
mount options so that the mount request succeeds.
When an automount trigger exists for a particular server file system, the automount trigger takes
precedence over mirror mounting, so a mirror mount will not occur for that file system. To use
mirror mounts in this case, the automount entry must be removed.
In the Oracle Solaris 11 release, accessing the /net or /home automount point causes a mount
of the /net or /home server namespace. Access to directories or files under those directories is
given through the mirror mounts facility.
For specific instructions about how to use mirror mounts, see “How to Mount All File Systems
From a Server” on page 77.
Unmounting a File System Using Mirror Mounts
Mirror-mounted file systems are automatically unmounted if they are idle after a certain
period of inactivity. The period is set by using the timeout parameter, which is used by the
automounter for the same purpose.
Chapter 2 • Network File System Features
49
How NFS Referrals Work
If an NFS file system is manually unmounted, then any mirror-mounted file systems contained
within it are also unmounted, if idle. If a mirror-mounted file system is active, the manual
unmount fails as though that original file system were busy. However, a forced unmount is
propagated through all the contained mirror-mounted file systems.
If a file system boundary is encountered within an automounted file system, a mirror mount
occurs. When the automounter unmounts the parent file system, any mirror-mounted file
systems within it are also automatically unmounted, if idle. If there is an active mirrormounted file system, the automatic unmount does not occur, which preserves current automount
behavior.
How NFS Referrals Work
Starting with the Oracle Solaris 11.1 release, NFS referrals enable an NFS Version 4 server to
point to file systems located on other NFS Version 4 servers as a way of connecting multiple
NFS Version 4 servers into a uniform namespace.
NFS Version 2, NFS Version 3, and other types of clients can follow a referral because it
appears to them to be a symbolic link.
When to Use NFS Referrals
NFS referrals are useful when you want to create what appears to be a single set of file names
across multiple servers, and you prefer not to use autofs for this purpose. Note that only NFS
Version 4 servers can be used and that the servers must be running at least the Oracle Solaris
11.1 release to host a referral.
Creating an NFS Referral
You create an NFS referral by using the nfsref command. When a referral is created and the
mount point does not yet exist, a symbolic link is generated. This symbolic link includes a
special flag that identifies an object as a reparse point. A reparse point is a special marker used
to note that special handling is required. If the reparse point already exists, NFS service data is
added or replaces existing NFS service data, as appropriate.
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How Autofs Works
Removing an NFS Referral
You remove NFS referral by using the nfsref command. The command removes NFS service
data from the specified reparse point. It also removes the reparse point if no other types of
service data are present.
How Autofs Works
Autofs is a kernel file system that supports automatic mounting and unmounting. The
components that work together to accomplish automatic mounting are:
■
automount command
■
autofs file system
■
automountd daemon
Autofs is a client-side service that automatically mounts the appropriate file system. The
automount service, svc:/system/filesystem/autofs, which is called at system startup time,
reads the master map file auto_master to create the initial set of autofs mounts. These autofs
mounts are not automatically mounted at startup time but rather are points under which file
systems are mounted in the future. These points are also known as trigger nodes. For more
information about starting the navigation process, see “How Autofs Starts the Navigation
Process” on page 59.
The following figure shows how the autofs service starts the automount command.
Chapter 2 • Network File System Features
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How Autofs Works
FIGURE 3
svc:/system/filesystem/autofs Service Starts automount
After the autofs mounts are set up, these mounts can trigger file systems to be mounted under
them. For example, when autofs receives a request to access a file system that is not currently
mounted, autofs calls automountd, which actually mounts the requested file system.
When a request is made to access a file system at an autofs mount point, the following occurs:
1. Autofs intercepts the request.
2. Autofs sends a message to the automountd daemon for the requested file system to be
mounted.
3. The automountd daemon locates the file system information in a map, creates the trigger
nodes, and performs the mount.
4. Autofs allows the intercepted request to proceed.
5. Autofs unmounts the file system after a period of inactivity.
After initially mounting autofs mounts, use the automount command to update autofs mounts
as necessary. The command compares the list of mounts in the auto_master map with the list
of mounted file systems in the mount table file /etc/mnttab (formerly /etc/mtab). automount
then makes the appropriate changes. This process enables system administrators to change
mount information within auto_master and have those changes used by the autofs processes
without stopping and restarting the autofs daemon. After the file system is mounted, further
access does not require any action from automountd until the file system is automatically
unmounted.
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How Autofs Works
Unlike mount, automount does not read the /etc/vfstab file (which is specific to each
computer) for a list of file systems to mount. The automount command is controlled within a
domain and on computers through the namespace or local files.
Note - Mounts that are managed through the autofs service should not be manually mounted
or unmounted. Even if the operation is successful, the autofs service does not check that the
object has been unmounted, resulting in possible inconsistencies. A reboot clears all the autofs
mount points.
How Autofs Navigates Through the Network
Autofs searches a series of maps to navigate through the network. Maps are files that contain
information such as the password entries of all users on a network or the names of all host
computers on a network. Effectively, the maps contain network-wide equivalents of UNIX
administration files. Maps are available locally or through a network name service such as NIS
and LDAP.
Autofs Maps
Autofs uses three types of maps:
■
■
■
Master map
Direct maps
Indirect maps
Master Autofs Map
The auto_master map associates a directory with a map. The map is a master list that specifies
all the maps that autofs should check. The following example shows the types of information
that an auto_master file could contain.
EXAMPLE 1
Sample /etc/auto_master File
# Master map for automounter
#
+auto_master
/net
-hosts
-nosuid,nobrowse
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How Autofs Works
/home
/nfs4
/-
auto_home
-fedfs
auto_direct
-nobrowse
-ro,nosuid,nobrowse
-ro
This example shows the generic auto_master file with one addition for the auto_direct map.
Each line in the master map /etc/auto_master has the following syntax:
mount-point map-name [mount-options]
mount-point
Full (absolute) path name of a directory. If the directory does not exist,
autofs creates the directory if possible. If the directory exists and is not
empty, mounting on the directory hides its contents. In this situation,
autofs issues a warning.
The notation /- as a mount point indicates that this particular map is a
direct map. The notation also means that no particular mount point is
associated with the map.
map-name
Name of the map that autofs uses to find directions to locations, or
mount information. If the name is preceded by a slash (/), autofs
interprets the name as a local file. Otherwise, autofs searches for the
mount information by using the search that is specified in the nameservice switch configuration file (/etc/nsswitch.conf). Special
maps are also used for /net. For more information, see “Mount Point
/net” on page 55.
mount-options
An optional, comma-separated list of options that apply to the mounting
of the entries that are specified in map-name, unless the entries in mapname list other options. Options for each specific type of file system
are listed in the mount man page for that file system. For information
about NFS-specific mount options, see the mount_nfs(1M) man page.
For NFS-specific mount points, the bg (background) and fg (foreground)
options do not apply.
A line that begins with # is a comment. All the text that follows until the end of the line is
ignored.
To split long lines into shorter ones, put a backslash (\) at the end of the line. The maximum
number of characters of an entry is 1024.
Note - If the same mount point is used in two entries, the first entry is used by the automount
command. The second entry is ignored.
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Mount Point /home
The mount point /home is the directory under which the entries that are listed in /etc/
auto_home (an indirect map) are to be mounted.
Note - Autofs runs on all computers and supports /net and /home (automounted home
directories) by default. You can override these defaults entries in the NIS auto.master map or
by local editing of the /etc/auto_master file.
Mount Point /net
Autofs mounts under the directory /net all the entries in the special built-in map -hosts that
uses only the hosts database. Suppose that the computer system1 is in the hosts database and it
exports any of its file systems. The following command changes the current directory to the root
directory of the computer gumbo.
$ cd /net/gumbo
Autofs can mount only the exported file systems of host system1, that is, those file systems
on a server that are available to network users instead of those file systems on a local disk.
Therefore, all the files and directories on system1 might not be available through /net/
system1.
With the /net method of access, the server name is in the path and is location dependent. If
you want to move an exported file system from one server to another, the path might no longer
work. Instead, you should set up an entry in a map specifically for the file system you want
rather than using /net.
Note - Using NFS Version 3 and earlier protocols, autofs checks the server's export list only
at mount time. After a server's file systems are mounted, autofs does not check with the
server again until the server's file systems are automatically unmounted. Therefore, newly
exported file systems are not “seen” until the file systems on the client are unmounted and then
remounted. For systems using NFS Version 4, mirror mounts reflect any dynamic changes made
to the list of exported file systems on the server.
Mount Point /nfs4
The /nfs4 mount point uses a pseudo-map to mount the FedFS domain root. A reference
to the /nfs4/example.net file results in an attempt to find the domain root for the DNS
Chapter 2 • Network File System Features
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How Autofs Works
domain example.net and mounts it at that location. Mounting a path under /nfs4 requires
that the DNS server returns a record, as described in “Set Up a DNS Record for a FedFS
Server” on page 91.
Direct Autofs Maps
A direct map is an automount point. With a direct map, a direct association exists between a
mount point on the client and a directory on the server. Direct maps have a full path name and
indicate the relationship explicitly. The following example shows a typical /etc/auto_direct
map:
/usr/local
/bin
/share
/src
/usr/man
-ro \
/usr/games
/usr/spool/news
-ro
-ro
-ro
system1:/export/local/sun4 \
system1:/export/local/share \
system1:/export/local/src
system2:/usr/man \
system3:/usr/man \
system4:/usr/man
system5:/usr/games
system6:/usr/spool/news \
system4:/var/spool/news
Lines in direct maps have the following syntax:
key [mount-options] location
key
Path name of the mount point in a direct map.
mount-options
Options that you want to apply to this particular mount. These options
are required only if the options differ from the map default. Options for
each specific type of file system are listed in the mount man page for that
file system. For information about NFS specific mount options, see the
mount_nfs(1M) man page.
location
Location of the file system. One or more file systems are specified as
server:pathname for NFS file systems.
Note - The path name should not include an automounted mount point. The path name should
be the actual absolute path to the file system. For instance, the location of a home directory
should be listed as server:/export/home/username, not as server:/home/username.
As in the master map, a line that begins with # is a comment. All the text that follows until the
end of the line is ignored. Put a backslash at the end of the line to split long lines into shorter
ones.
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How Autofs Works
Of all the maps, the entries in a direct map most closely resemble the corresponding entries in
/etc/vfstab. An entry might appear in /etc/vfstab as follows:
dancer:/usr/local - /usr/local/tmp nfs - yes ro
The equivalent entry appears in a direct map as follows:
/usr/local/tmp
-ro
dancer:/usr/local
Note - No concatenation of options occurs between the automounter maps. Any options that
are added to an automounter map override all options that are listed in maps that are searched
earlier. For instance, options that are included in the auto_master map would be overridden by
corresponding entries in any other map.
For information about the features of direct autofs map, see “How Autofs Selects the Nearest
Read-Only Files for Clients” on page 61.
Mount Point /In Example 1, “Sample /etc/auto_master File,” on page 53, the mount point /- tells
autofs not to associate the entries in auto_direct with any specific mount point. Indirect maps
use mount points that are defined in the auto_master file. Direct maps use mount points that
are specified in the named map. Note that, in a direct map the key, or mount point, is a full path
name.
An NIS auto_master file can have only one direct map entry because the mount point must be
a unique value in the namespace. An auto_master file that is a local file can have any number
of direct map entries if entries are not duplicated.
Indirect Autofs Maps
An indirect map uses a substitution value of a key to establish the association between a mount
point on the client and a directory on the server. Indirect maps are useful for accessing specific
file systems, such as home directories. The auto_home map is an example of an indirect map.
Lines in indirect maps have the following general syntax:
key [mount-options] location
key
Name without slashes in an indirect map.
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How Autofs Works
mount-options
Options that you want to apply to this particular mount. These options are
required only if the options differ from the map default. Options for each
specific type of file system are listed in the mount man page for that file
system. For example, see the mount_nfs(1M) man page for NFS-specific
mount options.
location
Location of the file system. One or more file systems are specified as
server:pathname.
Note - The path name should not include an automounted mount point. The path name should
be the actual absolute path to the file system. For instance, the location of a directory should be
listed as server:/usr/local, not as server:/net/server/usr/local.
As in the master map, a line that begins with # is a comment. All the text that follows until the
end of the line is ignored. Put a backslash (\) at the end of the line to split long lines into shorter
ones. Example 1, “Sample /etc/auto_master File,” on page 53 shows an auto_master
map that contains the following entry:
/home
auto_home
-nobrowse
auto_home is the name of the indirect map that contains the entries to be mounted under /home.
A typical auto_home map might contain the following:
user1
user2
user3
user4
user5
user6
user7
-rw,nosuid
server1:/export/home/user1
server2:/export/home/user2
server3:/export/home/user3
server4:/export/home/user4
server5:/export/home/user5
server6:/export/home/user6
server7:/export/home/user7
As an example, assume that the previous map is on host master-server. Suppose that the user
user7 has an entry in the password database that specifies her home directory as /home/user7.
Whenever user7 logs in to computer master-server, autofs mounts the directory /export/
home/user7 that resides on the computer server7. Her home directory is mounted read-write,
nosuid.
Assume the following conditions occur: User user7's home directory is listed in the password
database as /home/user7. Anybody, including user7, has access to this path from any computer
that is set up with the master map referring to the auto_home map.
Under these conditions, user user7 can run login or rlogin on any of these computers and have
her home directory mounted in place for her.
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How Autofs Works
Furthermore, now user7 can also type the following command:
$ cd ~user1
Autofs mounts user1's home directory for user7 (if all permissions allow).
Note - No concatenation of options occurs between the automounter maps. Any options that
are added to an automounter map override all options that are listed in maps that are searched
earlier. For instance, options that are included in the auto_master map are overridden by
corresponding entries in any other map.
On a network without a name service, you have to change all the relevant files (such as /etc/
passwd) on all systems on the network to allow Linda access to her files. With NIS, make the
changes on the NIS master server and propagate the relevant databases to the slave servers.
How Autofs Starts the Navigation Process
The automount command reads the master map at system startup. Each entry in the master
map is a direct map name or an indirect map name, its path, and its mount options. The specific
order of the entries is not important.
FIGURE 4
Navigation Through the Master Map
This figure shows that automount compares entries in the master map with entries in the mount
table to generate a current list.
Chapter 2 • Network File System Features
59
How Autofs Works
Autofs Mount Process
What the autofs service does when a mount request is triggered depends on how the
automounter maps are configured. The mount process is generally the same for all mounts.
However, the final result changes with the mount point that is specified and the complexity of
the maps. The mount process includes the creation of the trigger nodes.
Simple Autofs Mount
To help explain the autofs mount process, assume that the following files are installed.
$ cat /etc/auto_master
# Master map for automounter
#
+auto_master
/net
-hosts
-nosuid,nobrowse
/home
auto_home
-nobrowse
/share
auto_share
$ cat /etc/auto_share
# share directory map for automounter
#
ws
gumbo:/export/share/ws
When the /share directory is accessed, the autofs service creates a trigger node for /share/ws,
which is an entry in /etc/mnttab that resembles the following entry:
-hosts /share/ws
autofs nosuid,nobrowse,ignore,nest,dev=###
When the /share/ws directory is accessed, the autofs service completes the process as follows:
1. Checks the availability of the server's mount service.
2. Mounts the requested file system under /share. Now the /etc/mnttab file contains the
following entries.
-hosts /share/ws
autofs nosuid,nobrowse,ignore,nest,dev=###
gumbo:/export/share/ws /share/ws nfs nosuid,dev=####
#####
Hierarchical Mounting
When multiple layers are defined in the automounter files, the mount process becomes more
complex. Suppose that you expand the /etc/auto_shared file from the previous example to
contain the following:
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How Autofs Works
# share directory map for automounter
#
ws
/
gumbo:/export/share/ws
/usr
gumbo:/export/share/ws/usr
The mount process is basically the same as the previous example when the /share/ws mount
point is accessed. In addition, a trigger node to the next level (/usr) is created in the /share/
ws file system so that the next level can be mounted if it is accessed. In this example, /export/
share/ws/usr must exist on the NFS server for the trigger node to be created.
Caution - Do not use the -soft option when specifying hierarchical layers. For more
information, see “Autofs Unmounting” on page 61.
Autofs Unmounting
The unmounting that occurs after a certain amount of idle time is from the bottom up (reverse
order of mounting). If one of the directories at a higher level in the hierarchy is busy, only file
systems below that directory are unmounted. During the unmounting process, any trigger nodes
are removed and then the file system is unmounted. If the file system is busy, the unmount fails
and the trigger nodes are reinstalled.
Caution - Do not use the -soft option when specifying hierarchical layers. If the -soft option
is used, requests to reinstall the trigger nodes can time out. The failure to reinstall the trigger
nodes leaves no access to the next level of mounts. The only way to clear this problem is to
have the automounter unmount all of the components in the hierarchy. The automounter can
complete the unmounting either by waiting for the file systems to be automatically unmounted
or by rebooting the system.
How Autofs Selects the Nearest Read-Only Files
for Clients
This section uses the following example direct map to help explain how autofs selects the
nearest read-only files for clients.
/usr/local
/bin
/share
/src
/usr/man
-ro \
-ro
ivy:/export/local/sun4\
ivy:/export/local/share\
ivy:/export/local/src
oak:/usr/man \
rose:/usr/man \
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61
How Autofs Works
/usr/games
/usr/spool/news
-ro
-ro
willow:/usr/man
peach:/usr/games
pine:/usr/spool/news \
willow:/var/spool/news
The mount points /usr/man and /usr/spool/news list more than one location, with three
locations for the first mount point and two locations for the second mount point. Any of
the replicated locations can provide the same service to any user. This procedure is sensible
only when you mount a file system that is read-only, as you must have some control over the
locations of files that you write or modify. You want to avoid modifying files on one server on
one occasion and, minutes later, modifying the “same” file on another server. The benefit is that
the best available server is used automatically without any effort by the user.
If the file systems are configured as replicas (see “What Is a Replicated File
System?” on page 42), the NFS clients have the advantage of using failover. Not only is
the best NFS server automatically determined, but if that server becomes unavailable, the client
automatically uses the next-best server.
An example of a good file system to configure as a replica is man pages. In a large network,
more than one server can export the current set of man pages. Which server you mount the man
pages from does not matter as long as the server is running and exporting its file systems. In the
direct map example, multiple mount locations are expressed as a list of mount locations in the
map entry.
/usr/man -ro oak:/usr/man rose:/usr/man willow:/usr/man
In this example, you can mount the man pages from the servers oak, rose, or willow. Which
server is best depends on a number of factors, including the following:
■
■
■
Number of servers that support a particular NFS protocol level
Proximity of the server
Weighting
During the sorting process, a count is taken of the number of servers that support each version
of the NFS protocol. Whichever version of the protocol is supported on the most servers
becomes the protocol that is used by default. This selection provides the client with the
maximum number of servers to depend on.
After the largest subset of servers with the same version of the protocol is found, that server
list is sorted by proximity. To determine proximity, IPv4 addresses are inspected to determine
which servers are in each subnet. Servers on a local subnet are given preference over servers on
a remote subnet. Preference for the closest server reduces latency and network traffic.
Note - Proximity cannot be determined for replicas that are using IPv6 addresses.
Figure 5, “Server Proximity,” on page 63 illustrates server proximity.
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How Autofs Works
FIGURE 5
Server Proximity
If several servers that support the same protocol are on the local subnet, the time to
connect to each server is determined and the fastest server is used. The sorting can also be
influenced by using weighting. For more information about weighting, see “Autofs and
Weighting” on page 65.
For example, if NFS Version 4 servers are more abundant on the local subnet, NFS Version 4
becomes the protocol that is used by default. However, the sorting process is more complex
when servers on the local subnet support different protocols. Here are some examples of how
the sorting process works:
■
Servers on the local subnet are given preference over servers on a remote subnet. So, if a
NFS Version 3 server is on the local subnet and the closest NFS Version 4 server is on a
remote subnet, the NFS Version 3 server is given preference. Likewise, if the local subnet
Chapter 2 • Network File System Features
63
How Autofs Works
■
■
consists of NFS Version 2 servers, they are given preference over remote subnets with NFS
Version 3 and NFS Version 4 servers.
If the local subnet consists of a varied number of NFS Version 2, NFS Version 3, and NFS
Version 4 servers, more sorting is required. The automounter prefers the highest version on
the local subnet. In this instance, NFS Version 4 is the highest version. However, if the local
subnet has more NFS Version 3 or NFS Version 2 servers than NFS Version 4 servers, the
automounter “bids down” from the highest version on the local subnet by one version. For
example, if the local subnet has three servers with NFS Version 4, three servers with NFS
Version 3, and ten servers with NFS Version 2, a NFS Version 3 server is selected.
Similarly, if the local subnet consists of a varied number of NFS Version 2 and NFS Version
3 servers, the automounter first looks at the which version represents the highest version on
the local subnet. Next, the automounter counts the number of servers that run each version.
If the highest version on the local subnet also represents the most servers, the highest
version is selected. If a lower version has more servers, the automounter bids down from
the highest version on the local subnet by one version. For example, if more NFS Version
2 servers are on the local subnet than NFS Version 3 servers, a NFS Version 2 server is
selected.
Note - Weighting is also influenced by parameters stored in the SMF repository. Specifically
the values for server_versmin, client_versmin, server_versmax and client_versmax can
exclude some versions from the sorting process. For more information about these parameters,
see “NFS Daemons” on page 160.
With failover, the sorting is checked at mount time when a server is selected. Multiple locations
are useful in an environment where individual servers might not export their file systems
temporarily.
Failover is particularly useful in a large network with many subnets. Autofs chooses the
appropriate server and is able to confine NFS network traffic to a segment of the local network.
If a server has multiple network interfaces, you can list the host name that is associated with
each network interface as if the interface were a separate server. Autofs selects the nearest
interface to the client.
Note - No weighting and no proximity checks are performed with manual mounts. The mount
command prioritizes the servers that are listed from left to right.
For more information, see automount(1M) man page.
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Autofs and Weighting
You can influence the selection of servers at the same proximity level by adding a weighting
value to the autofs map. For example:
/usr/man -ro oak,rose(1),willow(2):/usr/man
The numbers in parentheses indicate a weighting. Servers without a weighting have a value of
zero and, therefore, are most likely to be selected. The higher the weighting value, the lower the
chance that the server is selected.
Note - All other server selection factors are more important than weighting. Weighting is only
considered when selecting between servers with the same network proximity.
Variables in an Autofs Map Entry
You can create a client-specific variable by prefixing a dollar sign ($) to its name. The variable
helps you to accommodate different architecture types that are accessing the same file system
location. You can also use curly braces to delimit the name of the variable from appended letters
or digits. The following table shows the predefined map variables.
TABLE 1
Predefined Map Variables
Variable
Meaning
Derived From
Example
ARCH
Architecture type
uname -m
sun4
CPU
Processor type
uname -p
sparc
HOST
Host name
uname -n
system1
OSNAME
Operating system name
uname -s
SunOS
OSREL
Operating system release
uname -r
5.10
OSVERS
Operating system version (version of the
release)
uname -v
GENERIC
You can use variables anywhere in an entry line except as a key. For instance, suppose that you
have a file server that exports binaries for SPARC and x86 architectures from /usr/local/bin/
sparc and /usr/local/bin/x86 respectively. The clients can mount through a map entry such
as the following:
/usr/local/bin
-ro server:/usr/local/bin/$CPU
The same entry for all clients now applies to all architectures.
Chapter 2 • Network File System Features
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How Autofs Works
Note - Most applications that are written for any of the sun4 architectures can run on all sun4
platforms. The -ARCH variable is hard-coded to sun4.
Maps That Refer to Other Maps
Special characters used with map names in map entries in a file map affect how the map name
is processed.
■
■
■
A map entry +mapname that is used in a file map causes automount to read the specified
map as if it were included in the current file.
If mapname is not preceded by a slash, autofs treats the map name as a string of characters
and uses the name-service switch policy to find the map name. If the path name is an
absolute path name, automount checks a local map of that name.
If the map name starts with a dash (-), automount consults the appropriate built-in map,
such as hosts.
The svc:system/name-service/switch service contains the search order for the naming
services. The automount property in the config property group specifies the order that the
name service databases are searched when looking for automount entries. If no specific config/
automount property is specified, then the order defined in the config/default property is used.
EXAMPLE 2
Displaying the Search Order of Maps by the automount command
$ svcprop -p config svc:/system/name-service/switch
config/value_authorization astring solaris.smf.value.name-service.switch
config/printer astring user\ files
config/default astring files\ nis
config/automount astring files\ nis
The example shows that the maps in the local files are searched before the NIS maps. The same
would be true if the config/automount property was not specified because the config/default
entry would be used. Therefore, you can have a few entries in your local /etc/auto_home map
for the most commonly accessed home directories. You can then use the switch to fall back to
the NIS map for other entries.
bill
bonny
cs.csc.edu:/export/home/bill
cs.csc.edu:/export/home/bonny
After consulting the included map, if no match is found, automount continues scanning the
current map. Therefore, you can add more entries after a + entry.
bill
bonny
66
cs.csc.edu:/export/home/bill
cs.csc.edu:/export/home/bonny
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How Autofs Works
+auto_home
The map that is included can be a local file or a built-in map. Only local files can contain +
entries.
+/etc/auto_mystuff
+auto_home
+-hosts
# local map
# NIS map
# built-in hosts map
Note - You cannot use + entries in NIS maps.
Executable Autofs Maps
You can create an autofs map that executes some commands to generate the autofs mount
points. Executable autofs maps are useful if you need to be able to create the autofs structure
from a database or a flat file. The disadvantage to using an executable map is that the map
needs to be installed on each host. An executable map cannot be included in NIS and LDAP
name services.
The executable map must have an entry in the auto_master file.
/execute
auto_execute
The following example shows a sample executable map:
#!/bin/ksh
#
# executable map for autofs
#
case $1 in
src) echo '-nosuid,hard bee:/export1' ;;
esac
For this example to work, the file must be installed as /etc/auto_execute and must have the
executable bit set. Set permissions to 744. Under these circumstances, running the following
command causes the /export1 file system from bee to be mounted:
$ ls /execute/src
Default Autofs Behavior With Name Services
At boot time, autofs is invoked by the service svc:/system/filesystem/autofs and autofs
checks for the master auto_master map.
Chapter 2 • Network File System Features
67
How Autofs Works
Autofs uses the name service ordering specified in the config/automount property of the svc:
/system/name-service/switch service. If the config/automount property is not defined,
then the config/default property is used. If NIS is selected and autofs cannot find a map
that autofs can use, but does find a map name that contains one or more underscores, the
underscores are changed to dots to allow traditional NIS file names to work. Then autofs
checks the map again. For a name service switch setting of automount: files nis ldap, maps
would be found as shown in the following figure.
FIGURE 6
How Autofs Uses the Name Service
The screen activity for this session would resemble the following example.
68
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Autofs Reference
$ grep /home /etc/auto_master
/home
auto_home
$ ypmatch brent auto_home
Can't match key brent in map auto_home. Reason: no such map in
server's domain.
$ ypmatch brent auto.home
diskus:/export/home/diskus1/&
If “files” is selected as the name service, all maps are assumed to be local files in the /etc
directory. Autofs interprets a map name that begins with a slash (/) as local regardless of which
name service autofs uses.
Autofs Reference
This section describes more advanced autofs features and topics.
Autofs and Metacharacters
Autofs recognizes some characters as having a special meaning. For example, some characters
are used for substitutions and some characters are used to protect other characters from the
autofs map parser.
Ampersand (&)
If you have a map with many subdirectories specified, as in the following example, consider
using string substitutions.
john
mary
joe
able
baker
willow:/home/john
willow:/home/mary
willow:/home/joe
pine:/export/able
peach:/export/baker
You can use the ampersand character (&) to substitute the key wherever the key appears. If you
use the ampersand, the previous map changes to the following text:
john
mary
willow:/home/&
willow:/home/&
Chapter 2 • Network File System Features
69
Autofs Reference
joe
able
baker
willow:/home/&
pine:/export/&
peach:/export/&
You could also use key substitutions in a direct map in situations such as the following
example:
/usr/man
willow,cedar,poplar:/usr/man
You can also simplify the entry further as follows:
/usr/man
willow,cedar,poplar:&
Notice that the ampersand substitution uses the whole key string. Therefore, if the key in a
direct map starts with a / (as it should), the slash is included in the substitution. Consequently,
for example, you could not include the following entry:
/progs
&1,&2,&3:/export/src/progs
Autofs would interpret the example as follows:
/progs
/progs1,/progs2,/progs3:/export/src/progs
Asterisk (*)
You can use the universal substitute character, the asterisk (*), to match any key. For example,
you could mount the /export file system from all hosts through this map entry.
*
&:/export
Each ampersand is substituted by the value of any given key. Autofs interprets the asterisk as an
end-of-file character.
Autofs and Special Characters
If you have a map entry that contains special characters, you might have to mount directories
that have names that the autofs map parser cannot process properly. The autofs parser is
sensitive to names that contain colons, commas, and spaces, for example. These names should
be enclosed in double quotes, as in the following example:
/vms
/mac
70
-ro
-ro
vmsserver: - - - "rc0:dk1 - "
gator:/ - "Mr Disk - "
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
♦ ♦ ♦
3
C H A P T E R
3
Administering Network File Systems
This chapter provides information about how to perform NFS administration tasks such as
setting up NFS services, adding new file systems to a share, and mounting file systems. This
chapter also contains procedures that are used to configure and maintain NFS and FedFS
referrals.
This chapter contains the following topics:
■
■
■
■
■
■
■
“Automatic File System Sharing” on page 72
“Mounting File Systems” on page 74
“Setting Up the NFS Service” on page 81
“Administering the Secure NFS System” on page 85
“Administering WebNFS” on page 87
“Administering NFS Referrals” on page 90
“Administering FedFS” on page 91
Note - If your system has zones enabled and you want to use this feature in a non-global zone,
see Introduction to Oracle Solaris Zones.
About Administering Network File Systems
Your responsibilities as an NFS administrator depend on your site's requirements and your role
as a network administrator. If you are responsible for all the systems on your local network, you
might be responsible for determining the following:
■
■
■
Which systems can serve as dedicated NFS servers
Which systems can serve as both NFS servers and NFS clients
Which systems serve as NFS clients only
Maintaining a server after it has been set up involves the following tasks:
■
Sharing and unsharing file systems as necessary
Chapter 3 • Administering Network File Systems
71
Automatic File System Sharing
■
Modifying administrative files to update the lists of file systems your system mounts
automatically
Checking the status of the network
Diagnosing and fixing NFS-related problems as they arise
■
Setting up maps for autofs
■
■
A system can be both an NFS server and an NFS client. So, a system can be used to share local
file systems with remote systems and to mount remote file systems.
Automatic File System Sharing
In the Oracle Solaris 11 release, the share command creates permanent shares that are
automatically shared during system startup. Unlike previous releases, you do not need to edit
the /etc/dfs/dfstab file to record the information about shares for subsequent reboots. This
file is no longer used.
Task Map for File System Sharing
The following task map links to procedures that describe file system sharing using the NFS
service.
TABLE 2
File System Sharing (Task Map)
Task
Description
For Instructions
Establish automatic file system
sharing
Configures a server so that file systems
are automatically shared when the
server is rebooted.
“How to Set Up Automatic File
System Sharing” on page 72
Enable NFS server logging
Configures a server so that NFS
logging is run on selected file systems.
“How to Enable NFS Server
Logging” on page 73
How to Set Up Automatic File System Sharing
72
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Define the file systems to be shared.
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Enable NFS Server Logging
Note - NFS server processes do not start by default.
You can set the share.nfs property to share a ZFS file system.
$ zfs set share.nfs=on | off filesystem
For example:
$ zfs set share.nfs=on pond/amy
For information about the available command options, see the zfs_share(1M) man page.
3.
Verify that the file system is shared.
You can use the share command to get a list of all the shared file systems.
For example:
$ share
pond_amy
Next Steps
/pond/amy
nfs sec=sys,rw
The next step is to set up your autofs maps so that clients can access the file systems that you
have shared on the server. For more information about setting up autofs maps, see Table 6,
“Tasks for administering Autofs,” on page 95.
How to Enable NFS Server Logging
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Change file system configuration values.
You can change the settings in the/etc/nfs/nfslog.conf file in one of the following ways:
■
■
Change the data associated with the global tag to edit the default settings for all file
systems.
Add a new tag for the file system.
For information about the format of the/etc/nfs/nfslog.conf file, see the nfslog.conf(4)
man page.
3.
Define the file systems to use NFS server logging.
Chapter 3 • Administering Network File Systems
73
Mounting File Systems
Use the share command to define each file system. The tag that is used with the log=tag option
must be specified in the /etc/nfs/nfslog.conf file.
The following example uses the default settings in the global tag.
$ share -F nfs -o ro,log=global /export/ftp
4.
Verify that the options you specified are listed.
For example:
$ share -F nfs
export_share_man
usr_share_src
export_ftp
5.
/export/share/man sec=sys,ro
/usr/src
sec=sys,rw=eng
/export/ftp public,log=global,sec=sys,ro
Verify that the NFS log daemon, nfslogd, is running.
$ ps -ef | grep nfslogd
6.
Check the status of the nfslogd daemon.
$ svcadm restart network/nfs/server:default
Mounting File Systems
File systems can be mounted automatically when the system is booted, on demand from the
command line, or through the automounter. The automounter provides many advantages
over mounting at boot time or from the command line. However, many situations require a
combination of all three methods. Additionally, several ways of enabling or disabling processes
exist, depending on the options you use when mounting a file system.
Mounting File Systems Task Map
The following table lists the tasks that are associated with file system mounting.
TABLE 3
74
Mounting File Systems (Task Map)
Task
Description
For Instructions
Mount a file system at boot time
Enables a file system to be mounted
whenever a system is rebooted.
“How to Mount a File System at Boot
Time” on page 75
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Mount a File System at Boot Time
Task
Description
For Instructions
Mount a file system by using a
command
Mounts a file system when a system is
running. This procedure is useful for
testing.
“How to Mount a File System From
the Command Line” on page 76
Mount a file system with the
automounter
Enables access to a file system on
demand without using the command
line.
“Mounting With the
Automounter” on page 77
Mount all file systems with
mirror mounts
Mounts all of the file systems from one
server.
“How to Mount All File Systems From
a Server” on page 77
Start client-side failover
Enables the automatic failover to a
working file system if a server fails.
“How to Use Client-Side
Failover” on page 77
Disable mount access for a client
Disables the ability of one client to
access a remote file system.
“How to Disable Mount Access for
One Client” on page 78
Provide access to a file system
through a firewall
Enables access to a file system through
a firewall by using the WebNFS
protocol.
“How to Mount an NFS File System
Through a Firewall” on page 79
Mount a file system by using an
NFS URL
Enables access to a file system by
using an NFS URL. This process
provides file system access without
using the MOUNT protocol.
“How to Mount an NFS File
System by Using an NFS
URL” on page 79
How to Mount a File System at Boot Time
This procedure shows how to mount file systems at boot time instead of using the autofs
maps. This procedure must be completed on every NFS client that requires access to remote file
systems.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Add an entry for the file system to the /etc/vfstab file.
Entries in the /etc/vfstab file have the following syntax:
#device
#to mount
device
to fsck
mount
point
FS
type
fsck
pass
mount
at boot
mount
options
For information about the /etc/vfstab file entries, see the vfstab(4) man page.
Caution - NFS servers that also have NFS client vfstab entries must always specify the bg
option to avoid a system hang during reboot. For more information, see the mount(1M) man
page.
Chapter 3 • Administering Network File Systems
75
How to Mount a File System From the Command Line
3.
Enable the NFS client service.
$ svcadm enable -r nfs/client
Example 3
Entry in the Client's /etc/vfstab File
Assume that you want a client system to mount the /var/mail directory from the server wasp.
You want the file system to be mounted as /var/mail on the client, and you want the client to
have read-write access. You would add the following entry to the client's vfstab file:
wasp:/var/mail - /var/mail nfs - yes rw
How to Mount a File System From the Command
Line
Mounting a file system from the command line is often performed to test a new mount point.
This type of mount enables temporary access to a file system that is not available through the
automounter. You can unmount the file system with the umount command or by rebooting the
local system.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Mount the file system.
mount -F nfs -o specific-options resource mount-point
For example:
$ mount -F nfs -o ro bee:/export/share/local /mnt
For more information, see the mount_nfs(1M) man page.
In this example, the /export/share/local file system from the server bee is mounted readonly on /mnt on the local system.
Caution - The mount command does not provide warnings about invalid options. The command
silently ignores any options that cannot be interpreted. To prevent unexpected behavior, verify
all of the options that you use.
76
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Mount All File Systems From a Server
Mounting With the Automounter
Without any changes to the generic system, NFS clients can access remote file systems through
the /net mount point. For information about establishing and supporting mounts with the
automounter, see Table 6, “Tasks for administering Autofs,” on page 95. Type the following
command to mount the /export/share/local file system:
$ cd /net/bee/export/share/local
Because the automounter enables all users to mount file systems, root access is not required.
The automounter also automatically unmounts file systems, so you do not have to unmount file
systems manually after you no longer need to access them.
How to Mount All File Systems From a Server
The automatic mirror mount facility enables an NFS client to access all available file systems
shared using NFS from an NFS server after one mount from that server has succeeded. The
mirror mount occurs automatically and you only need to access the file system. For more
information, see “How Mirror Mounts Work” on page 49.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Mount the root of the exported namespace of the server.
This command mirrors the file system hierarchy from the server on the client. In this example, a
/mnt/export/share/local directory structure is created.
$ mount bee:/ /mnt
3.
Access a file system.
This command or any other command that accesses the file system causes the file system to be
mounted.
$ cd /mnt/export/share/local
How to Use Client-Side Failover
1.
Become an administrator.
Chapter 3 • Administering Network File Systems
77
How to Disable Mount Access for One Client
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
On the NFS client, mount the file system by using the ro option.
You can mount from the command line, through the automounter, or by adding an entry to the
/etc/vfstab file that resembles the following:
bee,wasp:/export/share/local - /usr/local nfs - no ro
Note - Servers that are running different versions of the NFS protocol cannot be mixed in a
command issued at the command line or in a vfstab entry. Mixing servers that support NFS
Version 2, NFS Version 3, or NFS Version 4 protocols can be performed only with autofs. In
autofs, the best subset of NFS Version 2, NFS Version 3, or NFS Version 4 servers is used.
How to Disable Mount Access for One Client
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Disable mount access for one client.
$ share -F nfs -o specific_options pathname
For example:
$ share -F nfs ro=-rose:eng /export/share/man
78
ro=-rose:eng
Access list that allows read-only mount access to all clients in the eng
network group except for the host named rose
/export/share/
man
File system to be shared
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Mount an NFS File System Through a Firewall
How to Mount an NFS File System Through a
Firewall
Before You Begin
This procedure requires that the file system on the NFS server be shared by using the public
option. Additionally, any firewalls between the NFS client and the NFS server must allow TCP
connections on port 2049. All file systems that are shared allow for public file handle access, so
the public option is applied by default.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Manually mount the file system by using a command such as the following:
$ mount -F nfs host:pathname mount-point
For example:
$ mount -F nfs bee:/export/share/local /mnt
In this example, the file system /export/share/local is mounted on the local client by using
the public file handle. An NFS URL can be used instead of the standard path name. If the public
file handle is not supported by the server bee, the mount operation fails.
Mount an NFS File System by Using an NFS URL
You can choose to include the public option with an NFS URL. Without the public option, the
MOUNT protocol is used if the public file handle is not supported by the server. The public
option forces the use of the public file handle, and the mount fails if the public file handle is not
supported.
Note - The NFS protocol version that is used when you mount the file system is the highest
version supported by both the NFS client and the NFS server. However, you can use the vers=#
option to select a specific NFS protocol version.
How to Mount an NFS File System by Using an NFS URL
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
Chapter 3 • Administering Network File Systems
79
How to Mount an NFS File System by Using an NFS URL
2.
Manually mount the file system by using an NFS URL.
$ mount -F nfs nfs://host[:port]/pathname mount-point
Example 4
Mounting an NFS File System by Using an NFS URL
$ mount -F nfs nfs://bee:3000/export/share/local /mnt
In this example, the /export/share/local file system is being mounted from the server bee by
using NFS port number 3000. The port number is not required, and by default the standard NFS
port number of 2049 is used.
Displaying Information About File Systems
Available for Mounting
The showmount command displays information about file systems that have been remotely
mounted or are available for mounting. You use the -e option to list the shared file systems. For
example:
$ /usr/sbin/showmount -e bee
export list for bee:
/export/share/local (everyone)
/export/home
tulip,lilac
/export/home2
rose
For information about other options, see the showmount(1M) man page.
In some environments, information about shared file systems and the systems that have
mounted them should not be displayed. You can set the showmount_info property of the
sharectl command to none, which ensures that the client cannot view the following file system
information:
■
■
■
Information about file systems that the client cannot access
Information about all the shared file systems
Information about other systems that have mounted the file systems
EXAMPLE 5
Restricting File System Information Displayed to Clients
bee$ sharectl set -p showmount_info=none nfs
The following information is displayed on the client rose:
80
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Setting Up the NFS Service
$ /usr/sbin/showmount -e bee
export list for bee:
/export/share/local (everyone)
/export/home2
rose
The information about the /export/home file system is no longer displayed.
Setting Up the NFS Service
This section describes some of the tasks that are necessary to set up the NFS service.
Note - NFS Version 4 is the default version of NFS supported in Oracle Solaris 11.2 and later.
TABLE 4
Setting Up the NFS Service
Task
Description
For Instructions
Start and stop the NFS server
Starts the NFS service if it has not
been started automatically. Stops the
NFS service. Normally, the service
does not need to be stopped.
“Starting and Stopping the NFS
Service” on page 81
Start and stop the automounter
Starts and stops the automounter. This
procedure is required when some of
the automounter maps are changed.
“Starting and Stopping the
Automounter” on page 81
Select different versions of NFS
Selects a NFS version other than NFS
Version 4 on the server and clients.
“Selecting Different Versions of
NFS” on page 82
Starting and Stopping the NFS Service
As an administrator, use the svcadm command to enable and disable the NFS service on the
server.
■
To enable the NFS service on the server:
$ svcadm enable network/nfs/server
■
To disable the NFS service on the server:
$ svcadm disable network/nfs/server
Starting and Stopping the Automounter
As an administrator, use the svcadm command to enable and disable the autofs daemon.
Chapter 3 • Administering Network File Systems
81
How to Select Different Versions of NFS on a Server
■
To enable the autofs daemon:
$ svcadm enable system/filesystem/autofs
■
To disable the autofs daemon:
$ svcadm disable system/filesystem/autofs
Selecting Different Versions of NFS
If you want to use a version of NFS other than NFS Version 4, you can select a different
version:
■
■
■
If you want to select a different version of NFS on the NFS server, see “How to Select
Different Versions of NFS on a Server” on page 82.
If you want to select a different version of NFS on the NFS client, see “How to Select
Different Versions of NFS on a Client” on page 83.
If you want to select a different version of NFS on the NFS client using the command
line, see “How to Use the mount Command to Select Different Versions of NFS on a
Client” on page 84.
How to Select Different Versions of NFS on a Server
You can select another version of NFS if you choose not to use NFS Version 4, which is set by
default.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Change SMF parameters to set the NFS Version numbers.
For example, if you want the server to provide only NFS Version 3, set the values for both the
server_versmax and server_versmin parameters to 3.
$ sharectl set -p server_versmax=3 nfs
$ sharectl set -p server_versmin=3 nfs
3.
If you want to disable server delegation, change the server_delegation property.
$ sharectl set -p server_delegation=off nfs
82
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Select Different Versions of NFS on a Client
NFS server delegation enables an NFS client to cache files until another NFS client needs
access to the same files. In NFS Version 4, server delegation is enabled by default. For more
information, see “Delegation in NFS Version 4” on page 35.
4.
If you want to set a common domain for clients and servers, change the
nfsmapid_domain property.
You can set a common domain for the clients and servers to enable user ID or group ID
mapping between the client and the server.
$ sharectl set -p nfsmapid_domain=my.example.com nfs
where my.example.com provides the common domain name.
For more information about the nfsmapid daemon, see “NFS Daemons” on page 160.
5.
Check whether the NFS service is running on the server.
$ svcs network/nfs/server
6.
If necessary, enable the NFS service.
If the NFS service is offline, type the following command to enable the service:
$ svcadm enable network/nfs/server
For information about configuring the NFS service, see “How to Set Up Automatic File System
Sharing” on page 72.
See Also
“Version Negotiation in NFS” on page 28
How to Select Different Versions of NFS on a Client
The following procedure explains how to control which version of NFS is used on the client.
The NFS version that is set by default is NFS Version 4.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Change SMF parameters to set the NFS Version numbers.
For example, if you want all file systems to be mounted using the NFS Version 3 protocol, set
the values for both the client_versmax and client_versmin parameters to 3.
$ sharectl set -p client_versmax=3 nfs
Chapter 3 • Administering Network File Systems
83
How to Use the mount Command to Select Different Versions of NFS on a Client
$ sharectl set -p client_versmin=3 nfs
3.
Mount NFS on the client.
$ mount server-name:/share-point /local-dir
See Also
server-name
Name of the server.
/share-point
Path of the remote directory
/local-dir
Path of the local mount point
“Version Negotiation in NFS” on page 28
How to Use the mount Command to Select Different Versions of
NFS on a Client
This procedure explains how to use the mount command to control which version of NFS
is used on a client for a particular mount. To find out how to modify the NFS version for
all file systems mounted by the client, see “How to Select Different Versions of NFS on a
Client” on page 83.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Mount the desired version of NFS on the client.
$ mount -o vers=value server-name:/share-point /local-dir
value
NFS version number
server-name
Name of the server
/share-point
Path of the remote directory
/local-dir
Path of the local mount point
Note - This command overrides the NFS client settings in the SMF repository.
See Also
84
“Version Negotiation in NFS” on page 28
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Administering the Secure NFS System
Administering the Secure NFS System
To use the Secure NFS system, all the systems that you are responsible for must have a domain
name. Typically, a domain is an administrative entity of several systems that is part of a larger
network. If you are running a name service, you should also establish the name service for the
domain. For information about name services, see Working With Oracle Solaris 11.3 Directory
and Naming Services: DNS and NIS.
Kerberos V5 authentication is supported by the NFS service. For more information, see Chapter
2, “Kerberos on Oracle Solaris” in Managing Kerberos and Other Authentication Services in
Oracle Solaris 11.3.
You can also configure the Secure NFS environment to use Diffie-Hellman authentication. For
more information about Diffie-Hellman authentication, see Chapter 9, “Configuring Network
Services Authentication” in Managing Kerberos and Other Authentication Services in Oracle
Solaris 11.3.
How to Set Up a Secure NFS Environment With DH
Authentication
1.
Assign a domain name.
Make the domain name known to each system in the domain. For information about setting up
a machine's NIS domain name, see “How to Set a Machine’s NIS Domain Name” in Working
With Oracle Solaris 11.3 Directory and Naming Services: DNS and NIS.
$ domainname domain-name
2.
Establish public keys and secret keys for your clients' users by using the newkey
command.
$ newkey -u username -s name-service
Users can establish personal secure RPC passwords by using the chkey command.
$ chkey -p -s name-service -m mechanism
When public keys and secret keys have been generated, the public keys and encrypted secret
keys are stored in the publickey database.
For information about these commands, see the newkey(1M) and the chkey(1) man pages.
Chapter 3 • Administering Network File Systems
85
How to Set Up a Secure NFS Environment With DH Authentication
3.
Verify that the name service is responding.
For example:
4.
■
If you are running NIS, verify that the ypbind daemon is running. For more information, see
“ypbind Not Running on NIS Client” in Working With Oracle Solaris 11.3 Directory and
Naming Services: DNS and NIS.
■
If you are running LDAP, verify that the ldap_cachemgr daemon is running. For more
information, see “Monitoring LDAP Client Status” in Working With Oracle Solaris 11.3
Directory and Naming Services: LDAP.
Verify that the keyserv daemon of the key server is running.
$ ps -ef | grep keyserv
root
100
1 16
Apr 11 ?
root 2215 2211 5 09:57:28 pts/0
0:00 /usr/sbin/keyserv
0:00 grep keyserv
If the daemon is not running, type the following to start the key server:
$ svcadm enable network/rpc/keyserv
5.
Decrypt and store the secret key.
Usually, the login password is identical to the network password. In this situation, keylogin
is not required. If the passwords are different, the users have to log in, and then run keylogin.
You still need to use the keylogin -r command as root to store the decrypted secret key in
/etc/.rootkey.
Note - You need to run keylogin -r if the root secret key changes or if the /etc/.rootkey file
is lost.
6.
Set the security mode for the file system to be shared.
For Diffie-Hellman authentication add the sec=dh option to the command line.
$ share -F nfs -o sec=dh /export/home
For more information about security modes, see the nfssec(5) man page.
7.
Update the automounter maps for the file system.
If you are using Diffie-Hellman authentication, edit the auto_master data to include sec=dh as
a mount option in the appropriate entries.
/home auto_home -nosuid,sec=dh
86
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Administering WebNFS
When you reinstall, move, or upgrade a system, remember to save the /etc/.rootkey file if
you do not establish new keys or change the keys for root. If you delete the /etc/.rootkey
file, type the following command:
$ keylogin -r
Administering WebNFS
This section provides instructions for administering the WebNFS system.
TABLE 5
Administering WebNFS (Task Map)
Task
Description
For Instructions
Plan for WebNFS
Issues to consider before enabling the
WebNFS service.
“Planning for WebNFS
Access” on page 87
Enable WebNFS
Enables mounting of an NFS file
system by using the WebNFS protocol.
“How to Enable WebNFS
Access” on page 88
Enable WebNFS through a
firewall
Enables access to files through
a firewall by using the WebNFS
protocol.
“Enabling WebNFS Access Through a
Firewall” on page 90
Browse by using an NFS URL
Uses an NFS URL within a web
browser.
“Accessing an NFS URL by Using a
Browser” on page 89
Use a public file handle with
autofs
Uses public file handle when mounting
a file system with the automounter.
“How to Use a Public File Handle
With Autofs” on page 107
Use an NFS URL with autofs
Adds an NFS URL to the automounter
maps.
“How to Use NFS URLs With
Autofs” on page 107
Provide access to a file system
through a firewall
Enables access to a file system through
a firewall by using the WebNFS
protocol.
“How to Mount an NFS File System
Through a Firewall” on page 79
Mount a file system by using an
NFS URL
Enables access to a file system by
using an NFS URL. This process
enables file system access without
using the MOUNT protocol.
“How to Mount an NFS File
System by Using an NFS
URL” on page 79
Planning for WebNFS Access
To use WebNFS, you first need an application that is capable of running and loading an NFS
URL (for example, nfs://server/path). The next step is to choose the file system that can
be exported for WebNFS access. If the application is web browsing, often the document root
Chapter 3 • Administering Network File Systems
87
How to Enable WebNFS Access
for the web server is used. You need to consider several factors when choosing a file system to
export for WebNFS access.
■
■
Each server has one public file handle that by default is associated with the server's root
file system. The path in an NFS URL is evaluated relative to the directory with which the
public file handle is associated. If the path leads to a file or directory within an exported file
system, the server provides access. You can use the public option of the share command to
associate the public file handle with a specific exported directory. Using this option enables
URLs to be relative to the shared file system rather than to the server's root file system. The
root file system does not allow web access unless the root file system is shared.
The WebNFS environment enables users who already have mount privileges to access
files through a browser. This capability is enabled regardless of whether the file system
is exported by using the public option. Because users already have access to these files
through the NFS setup, this access should not create any additional security risk. You only
need to share a file system by using the public option if users who cannot mount the file
system need to use WebNFS access.
■
File systems that are already open to the public make good candidates for using the public
option. Some examples are the top directory in an ftp archive or the main URL directory for
a web site.
■
You can use the index option with the share command to force the loading of an HTML
file. Otherwise, you can list the directory when an NFS URL is accessed.
After a file system is chosen, review the files and set access permissions to restrict viewing of
files or directories, as needed. Establish the permissions, as appropriate, for any NFS file system
that is being shared. For many sites, 755 permissions for directories and 644 permissions for
files provide the correct level of access.
You need to consider additional factors if both NFS and HTTP URLs are to be used to access
one web site. For more information about WebNFS limitations, see “WebNFS Limitations With
Web Browser Use” on page 45.
How to Enable WebNFS Access
Before You Begin
88
By default, all file systems that are available for NFS mounting are automatically available for
WebNFS access. Use this procedure for one of the following reasons:
■
To allow NFS mounting on a server that does not currently allow NFS mounting
■
To reset the public file handle to shorten NFS URLs by using the public option with the
share command
■
To force an HTML file to be loaded by using the index option with the share command
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Enable WebNFS Access
You can also use the sharectl utility to configure file-sharing protocols such as NFS. For more
information about configuring file sharing protocols, see the sharectl(1M) man page.
For information about issues to consider before starting the WebNFS service, see “Planning for
WebNFS Access” on page 87.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Define the file systems to be shared by the WebNFS service.
Use the share command to define each file system.
$ share -F nfs -o specific-options pathname
For information about the available options for the share_nfs command, see the
share_nfs(1M) man page.
3.
Verify that the options you specified are listed.
$ share -F nfs
For example:
$ share -F nfs
export_share_man /export/share/man sec=sys,ro
usr_share_src
/usr/src
sec=sys,rw=eng
export_ftp
/export/ftp
sec=sys,ro,public,index=index.html
Accessing an NFS URL by Using a Browser
Browsers that are capable of supporting the WebNFS service should provide access to an NFS
URL that resembles the following:
nfs://server<:port>/path
server
Name of the file server
port
Port number to use (2049, default value)
path
Path to file, which can be relative to the public file handle or to the root
file system
Chapter 3 • Administering Network File Systems
89
Administering NFS Referrals
Note - In most browsers, the URL service type (for example, nfs or http) is remembered from
one transaction to the next. The exception occurs when a URL that includes a different service
type is loaded. For example, if a reference to an HTTP URL is loaded after you use an NFS
URL, subsequent pages are loaded by using the HTTP protocol instead of the NFS protocol.
Enabling WebNFS Access Through a Firewall
You can enable WebNFS access for clients that are not part of the local subnet by configuring
the firewall to allow a TCP connection on port 2049. Just allowing access for httpd does not
allow NFS URLs to be used.
Administering NFS Referrals
An NFS referral enables an NFS Version 4 server to point to file systems that are located on
other NFS Version 4 servers as a way of connecting multiple NFS Version 4 servers into a
uniform namespace.
How to Create and Access an NFS Referral
1.
On an NFS server, create a referral.
Add the referral on an NFS-shared file system, pointing to one or more existing NFS-shared file
systems. For example:
server1 nfsref add /share/docs server2:/usr/local/docs server3:/tank/docs
Created reparse point /share/docs
2.
Verify that the referral was created.
server1$ nfsref lookup /share/docs
/share/docs points to:
server2:/usr/local/docs
server3:/tank/docs
3.
On the client, access the mount point to mount the referral.
client1$ ls /share/docs
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Remove an NFS Referral
If the mount fails, check the connectivity on the NFS client and check the shared file system on
the NFS server. For more information about troubleshooting NFS, see “NFS Troubleshooting
Procedures” on page 140.
Example 6
Modifying an Existing NFS Referral
To add another file system, such as server4:/tank/docs, to the existing referral that was
created in this procedure, you would type the command from Step 2 with the new file system.
server1$ nfsref add /share/docs server2:/usr/local/docs \
server3:/tank/docs server4:/tank/docs
The add subcommand replaces the information in the current referral with the new information
from the command.
How to Remove an NFS Referral
To remove an NFS referral, type the following command:
server1$ nfsref remove /share/docs
Removed svc_type 'nfs-basic' from /share/docs
This removes a single referral that was created at /share/docs.
Administering FedFS
You use the FedFS protocol to construct and maintain a federated file system. This file system
can include many different file servers to create a multivendor global namespace.
Set Up a DNS Record for a FedFS Server
After an appropriate DNS record is created, mounting a file system using FedFS is completed
by the automounter after the mount point has been accessed. The DNS record for the server
appears similar to the following:
$ nslookup -q=srv _nfs-domainroot._tcp.example.com bee.example.com
Chapter 3 • Administering Network File Systems
91
How to Create a Namespace Database
Server:
Address:
bee.example.com
192.0.2.0
_nfs-domainroot._tcp.example.com
service = 1 0 2049 bee.example.com.
After you set up the DNS record, Oracle Solaris will mount the FedFS file system automatically
when an application accesses the /nfs4/example.com mount point.
How to Create a Namespace Database
A namespace database (NSDB) is used to provide information about the set of files from
different types of servers that are combined into a single FedFS namespace. This procedure is
performed on the LDAP server.
Before You Begin
1.
You must have an LDAP server installed. For more information, see Chapter 4, “Setting Up
the Oracle Directory Server Enterprise Edition With LDAP Clients” in Working With Oracle
Solaris 11.3 Directory and Naming Services: LDAP.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Update the /etc/openldap/slapd.conf file with the following entries:
include
/usr/lib/fs/nfs/fedfs-11.schema
suffix dc=example,dc=org
rootdn cn=Manager,dc=example,dc=org
rootpw password
3.
Create a distinguished name for the FedFS data.
$ nsdb-update-nci -l NSDB -r port -D bind_DN -w bind-PW nce
For example:
$ nsdb-update-nci -l localhost -r 389 -D cn=Manager -w\
example.org dc=example,dc=org adding new entry "dc=example,dc=org"
NCE entry created
92
-l
Specifies the LDAP server implementing the NSDB
-r
Specifies the port on which the LDAP server implementing the NSDB is
listening
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Use a Secured Connection to the NSDB
-D
Specifies the distinguished name of a user permitted to change the NSDB
information
-w
Specifies the password for the bind DN user
For more information, see the nsdb-update-nci(1M) man page.
How to Use a Secured Connection to the NSDB
Before You Begin
1.
You must have an LDAP server installed. For more information, see Chapter 4, “Setting Up
the Oracle Directory Server Enterprise Edition With LDAP Clients” in Working With Oracle
Solaris 11.3 Directory and Naming Services: LDAP.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
On the LDAP server, create a certificate.
You need a certificate to secure the LDAP traffic.
$
$
$
$
mkdir /etc/openldap/certs
mkdir /etc/openldap/certs/keys
cd /etc/openldap/certs
openssl req -x509 -nodes -days 3650 -newkey rsa:2048 \
-keyout keys/ldapskey.pem -out ldapscert.pem
$ chown -R openldap:openldap /etc/openldap/certs/*
$ chmod 0400 keys/ldapskey.pem
3.
Add declarations to the /etc/openldap/slapd.conf file.
TLSCertificateFile /etc/openldap/certs/ldapscert.pem
TLSCertificateKeyFile /etc/openldap/certs/keys/ldapskey.pem
4.
Copy the certificate to the NFS server and clients.
$ scp ldap-server:/etc/openldap/certs/keys/ldapskey.pem \
/etc/openldap/certs/keys/ldapskey.pem
$ chmod 0400 /etc/openldap/certs/keys/ldapskey.pem
5.
On the NFS server and clients, update the connection entry.
$ nsdbparams update -f ldapscert.pem -t FEDFS_SEC_TLS localhost
Chapter 3 • Administering Network File Systems
93
How to Create a FedFS Referral
For information about options available with the nsdbparams command, see the
nsdbparams(1M) man page.
How to Create a FedFS Referral
Before You Begin
You must have an NFS server installed.
1.
Become an administrator.
2.
Create a connection entry for an NSDB.
This command creates a connection entry between the NSDB that is defined on the LDAP
server and an NFS server.
$ nsdbparams update -D cn=Manager,dc=example,dc=org -w example.org nsdb.example.org
3.
Create a FedFS referral.
$ nfsref -t svc-type add path location
-t svc-type
Specifies the service type of the referral
For example:
$ nfsref -t nfs-fedfs add /share/docs server2:/usr/local/docs server3:/tank/docs
Created reparse point /share/doc
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
♦ ♦ ♦
4
C H A P T E R
4
Administering Autofs
This chapter provides information about how to perform autofs administration tasks such as
accessing file systems, modifying autofs maps, and using security restrictions with autofs.
This chapter contains the following topics:
■
■
■
■
“Autofs Administration” on page 95
“Using SMF Parameters to Configure Your Autofs Environment” on page 97
“Modifying the Maps” on page 98
“Customizing the Automounter” on page 100
Note - If your system has zones enabled and you want to use this feature in a non-global zone,
see Introduction to Oracle Solaris Zones.
Autofs Administration
The following table provides a description and a pointer to many of the tasks that are related to
autofs.
TABLE 6
Tasks for administering Autofs
Task
Description
For Instructions
Start and stop autofs
Start and stop the automount service
without having to reboot the system
“Starting and Stopping the
Automounter” on page 81
Configure your autofs
environment through the autofs
SMF parameters
Assign values to parameters in the
SMF repository
“Using SMF Parameters
to Configure Your Autofs
Environment” on page 97
Access file systems by using
autofs
Access file systems by using the
automount service
“Mounting With the
Automounter” on page 77
Modify the autofs master map
Modify the master map, which is used
to list other maps
“How to Modify the Master
Map” on page 98
Modify an autofs indirect map
Modify an indirect map, which is used
for most maps
“How to Modify Indirect
Maps” on page 99
Chapter 4 • Administering Autofs
95
Autofs Administration
96
Task
Description
For Instructions
Modify an autofs direct map
Modify a direct map, which is used to
establish a direct association between a
mount point on a client and a server
“How to Modify Direct
Maps” on page 99
Modify the autofs maps to
access non-NFS file systems
Set up an autofs map with an entry for
a CD-ROM application
“Accessing Non-NFS File
Systems” on page 100
Use /home maps
■ Set up a common /home map
■ Set up a /home map that refers to
multiple file systems
■ “Setting Up a Common View of
/home” on page 100
■ “How to Set Up /home With
Multiple Home Directory File
Systems” on page 101
Using a new autofs mount point
■ Set up a project-related autofs
map
■ Set up an autofs map that supports
different client architectures
■ Set up an autofs map that supports
different operating systems
■ “How to Consolidate ProjectRelated Files Under a Common
Directory” on page 102
■ “How to Set Up Different
Architectures to Access a Shared
Namespace” on page 104
■ “How to Support Incompatible
Client Operating System
Versions” on page 105
Replicate file systems with
autofs
Provide access to file systems that fail
over
“How to Replicate Shared Files Across
Several Servers” on page 106
Using security restrictions with
autofs
Provide access to file systems while
restricting remote root access to the
files
“How to Apply Autofs Security
Restrictions” on page 106
Using a public file handle with
autofs
Force use of the public file handle
when mounting a file system
“How to Use a Public File Handle
With Autofs” on page 107
Using an NFS URL with autofs
Add an NFS URL so that the
automounter can use it
“How to Use NFS URLs With
Autofs” on page 107
Disable autofs browsability
■ Disable browsability so that
autofs mount points are not
automatically populated on a single
client
■ Disable browsability so that
autofs mount points are not
automatically populated on all
clients
■ Disable browsability so that a
specific autofs mount point is not
automatically populated on a client
■ “How to Completely Disable
Autofs Browsability on a Single
NFS Client” on page 108
■ “How to Disable Autofs
Browsability for All
Clients” on page 108
■ “How to Disable Autofs
Browsability on a Selected File
System” on page 108
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Using SMF Parameters to Configure Your Autofs Environment
Using SMF Parameters to Configure Your Autofs
Environment
You can use SMF parameters to configure your autofs environment. Specifically, this facility
provides an additional way to configure your autofs commands and autofs daemons. You
can make the same specifications with the sharectl command that you would make on the
command line. You can make your specifications by providing values to keywords.
How to Configure Your Autofs Environment Using
SMF Parameters
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Add or modify an autofs SMF parameter.
For example, if you want to turn off browsing for all autofs mount points, use the following
command:
$ sharectl set -p nobrowse=on autofs
The nobrowse keyword is equivalent to the -n option of the automountd command. For
information about parameters supported for autofs, see autofs(4).
3.
Restart the autofs daemon.
$ svcadm restart system/filesystem/autofs
Administrative Tasks Involving Maps
Your choice of a map and name service type affects the mechanism that you need to use to
make changes to the autofs maps.
Note - Use indirect maps whenever possible. Indirect maps are easier to construct and less
demanding on the systems' file systems. Also, indirect maps do not occupy as much space in the
mount table as direct maps.
Chapter 4 • Administering Autofs
97
Modifying the Maps
The types of maps and their uses are:
■
Master – Associates a directory with a map
■
Direct – Directs autofs to specific file systems
■
Indirect – Directs autofs to reference-oriented file systems
The way that you make changes to your autofs environment depends on your name service.
To make changes if you are using local files as a name service, use a text editor. If your name
service is NIS or LDAP, make changes as required in these name services.
You might have to run the automount command depending on the modification you have made
to the type of map. For example, if you have made an addition or a deletion to a direct map,
you need to run the automount command on the local system. By running the command, you
make the change effective. However, if you have modified an existing entry, you do not need
to run the automount command for the change to become effective. You always have to run
the automount command if you make changes to the master map. You never have to run the
automount command if you make changes to the indirect map.
Modifying the Maps
This section describes how to update several types of automounter maps.
How to Modify the Master Map
1.
Log in as a user who has permissions to change the maps based on the name
service that you are using. If you are using the local map files, assume the root
role.
2.
Make your changes to the master map.
The specific steps needed to change the map depends on the name service that you are using.
if you are using local files as a name service, use a text editor. If your name service is NIS, use
make files.
3.
For each client, become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
4.
98
For each client, run the automount command to make your changes effective.
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Modify Indirect Maps
5.
Notify your users to run the automount command as superuser on their own
systems in order to incorporate the new information from the master map.
How to Modify Indirect Maps
1.
Log in as a user who has permissions to change the maps.
2.
Make your changes to the indirect map.
The specific steps needed to change the map depends on the name service that you are using.
How to Modify Direct Maps
1.
Log in as a user who has permissions to change the maps.
2.
Make your changes to the direct map.
The specific steps needed to change the map depends on the name service that you are using.
3.
Notify your users of the changes.
Notification is required so that the users can run the automount command as superuser on their
own systems, if necessary.
Note - If you only modify or change the contents of an existing direct map entry, you do not
need to run the automount command.
For example, suppose you modify the auto_direct map so that the /usr/src directory is now
mounted from a different server. If /usr/src is not mounted at this time, the new entry becomes
effective immediately when you try to access /usr/src. If /usr/src is mounted now, you can
wait until the auto-unmounting occurs, then access the file.
Avoiding Mount Point Conflicts
If you have a local disk partition that is mounted on /src and you plan to use the autofs
service to mount other source directories, the NFS service hides the local partition whenever
you try to reach it. Therefore, You need to mount the partition in some other location.
Chapter 4 • Administering Autofs
99
Accessing Non-NFS File Systems
For example, to mount the partition on /export/src you would add an entry in the /etc/
vfstab file such as the following:
/dev/dsk/d0t3d0s5 /dev/rdsk/c0t3d0s5 /export/src ufs 3 yes -
You also need to add an entry in auto_src. In this example, the name of the system is terra.
terra terra:/export/src
Accessing Non-NFS File Systems
Autofs can also mount files other than NFS files, for example, files on removable media, such
as CD-ROM or USB flash drives.
Instead of mounting a file system from a server, you put the media in the drive and reference
the file system from the map. For example, to access a CD-ROM application, become an
administrator and add an entry for the CD-ROM file system similar to the following example in
the autofs map, with the CD-ROM device name following the colon:
hsfs
-fstype=hsfs,ro
:/dev/sr0
Customizing the Automounter
This section describes how to customize the automounter maps to provide an easy-to-use
directory structure.
Setting Up a Common View of /home
The ideal is for all network users to be able to locate their own home directories or the home
directories of other users under /home. This view should be common across all systems,
whether client or server.
Every Oracle Solaris installation comes with a master map: /etc/auto_master.
# Master map for autofs
#
+auto_master
/net
-hosts
-nosuid,nobrowse
/home
auto_home -nobrowse
/nfs4
-fedfs
-ro,nosuid,nobrowse
100
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Set Up /home With Multiple Home Directory File Systems
A map for auto_home is also installed under /etc. When a new local user is created, an entry is
automatically added to /etc/auto_home. For example:
# Home directory map for autofs
#
rusty dragon:/export/home/&
+auto_home
On the server named dragon, the home directory for rusty can be accessed through /export/
home/rusty as well as /home/rusty.
With the auto_home map in place, users can refer to any home directory (including their own)
with the path /home/user. user is their login name and the key in the map. This common view
of all home directories is valuable when logging in to another user's system. Autofs mounts
your home directory for you. Similarly, if you run a remote windowing system client on another
system, the client program has the same view of the /home directory. This common view also
extends to the server.
Users do not need to be aware of the real location of their home directories. If a user needs
more disk space and needs to have the home directory relocated to another server, you need
only change the user's entry in the auto_home map to reflect the new location. Other users can
continue to use the /home/user path.
Note - Do not permit users to run setuid executables from their home directories. Without this
restriction, any user could have superuser privileges on any system.
How to Set Up /home With Multiple Home Directory
File Systems
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Install home directory partitions under /export/home.
If the system has several partitions, install the partitions under separate directories, for example,
/export/home1 and /export/home2.
3.
Update the auto_home map.
Whenever you create a new user account, type the location of the user's home directory in the
auto_home map. Map entries can be simple, for example:
Chapter 4 • Administering Autofs
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How to Consolidate Project-Related Files Under a Common Directory
user1
user2
user3
user4
system1:/export/home1/&
system1:/export/home1/&
system2:/export/home2/&
system1:/export/home3/&
Notice the use of the & (ampersand) as a substitute for the map key. The ampersand is an
abbreviation for the second occurrence of user1 in the following example:
user1
system1:/export/home1/user1
How to Consolidate Project-Related Files Under a
Common Directory
You can use autofs to consolidate files in a directory that is common across multiple systems.
You can add the directory structure of the project-related files to the autofs map for the
common directory. This directory structure enables the users to use the project files irrespective
of physical and hardware changes in the systems.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Add an entry for the common directory to the auto_master map.
/common-dir
auto_common-dir
-nosuid
The auto_common-dir map determines the contents of the common directory.
3.
Add the -nosuid option as a precaution to prevent users from running the setuid
programs that might exist in any workspace.
4.
Add entries to the auto_common-dir map.
The auto_common-dir map is organized so that each entry describes a subproject. Your first
attempt yields a map that resembles the following:
project1
project2
app1
system1:/export/common-dir/&
system1:/export/common-dir/&
system2:/export/common-dir/&
The ampersand (&) at the end of each entry is an abbreviation for the entry key.
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How to Consolidate Project-Related Files Under a Common Directory
Example 7
Consolidating Project-Related Files Under /ws
Assume that you are the administrator of a large software development project. You plan to
make all project-related files available under a directory that is called /ws. This directory is to
be common across all workstations at the site.
Add an entry for the /ws directory to the site auto_master map.
/ws
auto_ws
-nosuid
The auto_ws map determines the contents of the /ws directory. The -nosuid prevents users from
running setuid programs that might exist in any workspaces. Add entries to the auto_ws map
such that each entry describes a subproject. Your first attempt yields a map that resembles the
following:
compiler
windows
files
drivers
man
tools
alpha:/export/ws/&
alpha:/export/ws/&
bravo:/export/ws/&
alpha:/export/ws/&
bravo:/export/ws/&
delta:/export/ws/&
The ampersand (&) at the end of each entry is an abbreviation for the entry key. For instance, the
first entry is equivalent to the following:
compiler alpha:/export/ws/compiler
This first attempt provides a map that appears simple, but additional refinements are necessary.
The project organizer decides that the documentation in the man entry should be provided as a
subdirectory under each subproject. Also, each subproject requires subdirectories to describe
several versions of the software. You must assign each of these subdirectories to an entire disk
partition on the server.
Modify the entries in the map as follows:
compiler \
/vers1.0
/vers2.0
/man
windows \
/vers1.0
/man
files \
/vers1.0
/vers2.0
/vers3.0
/man
drivers \
/vers1.0
alpha:/export/ws/&/vers1.0 \
bravo:/export/ws/&/vers2.0 \
bravo:/export/ws/&/man
alpha:/export/ws/&/vers1.0 \
bravo:/export/ws/&/man
alpha:/export/ws/&/vers1.0 \
bravo:/export/ws/&/vers2.0 \
bravo:/export/ws/&/vers3.0 \
bravo:/export/ws/&/man
alpha:/export/ws/&/vers1.0 \
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How to Set Up Different Architectures to Access a Shared Namespace
/man
tools \
/
bravo:/export/ws/&/man
delta:/export/ws/&
Although the map now appears to be much larger, the map still contains only the five entries.
Each entry is larger because each entry contains multiple mounts. For instance, a reference to
/ws/compiler requires three mounts for the vers1.0, vers2.0, and man directories.
The backslash at the end of each line indicates that the entry is continued onto the next line.
Effectively, the entry is one long line, though line breaks and some indenting have been used to
make the entry more readable.
The tools directory contains software development tools for all subprojects, so this directory
is not subject to the same subdirectory structure. The tools directory continues to be a single
mount.
This arrangement provides the administrator with much flexibility. Software projects typically
consume substantial amounts of disk space. Through the life of the project, you might be
required to relocate and expand various disk partitions. If these changes are reflected in the
auto_ws map, you do not need to notify the users because the directory hierarchy under /ws is
not changed.
Because the servers alpha and bravo view the same autofs map, any users who log in to these
systems can find the /ws namespace as expected. These users are provided with direct access to
local files through loopback mounts instead of NFS mounts.
How to Set Up Different Architectures to Access a
Shared Namespace
You need to assemble a shared namespace for local executables, and applications, such as
spreadsheet applications and word-processing packages. The clients of this namespace use
several different workstation architectures that require different executable formats. Also, some
workstations are running different releases of the operating system.
104
1.
Create the auto_local map.
For more information about naming services, see Working With Oracle Solaris 11.3 Directory
and Naming Services: DNS and NIS.
2.
Choose a single, site-specific name for the shared namespace.
This name makes the files and directories that belong to this space easily identifiable. For
example, if you choose /usr/local as the name, the path /usr/local/bin is clearly a part of
this namespace.
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Support Incompatible Client Operating System Versions
3.
Create an autofs indirect map and choose a pathname to anchor it.
Mount this map at /usr/local. Set up the following entry in the NIS auto_master map:
/usr/local
auto_local
-ro
Notice that the -ro mount option means that clients cannot write to any files or directories.
4.
Export the appropriate directory on the server.
5.
Include a bin entry in the auto_local map.
Your directory structure resembles the following:
bin
aa:/export/local/bin
where, aa is the name of the server.
6.
(Optional) To serve clients of different architectures, change the entry by adding
the autofs CPU variable.
bin
aa:/export/local/bin/$CPU
where, aa is the name of the server.
■
For SPARC clients – Place executables in /export/local/bin/sparc.
■
For x86 clients – Place executables in /export/local/bin/i386.
How to Support Incompatible Client Operating
System Versions
1.
Combine the architecture type with a variable that determines the operating
system type of the client.
You can combine the autofs OSREL variable with the CPU variable to form a name that
determines both CPU type and OS release.
2.
Create the following map entry.
bin
aa:/export/local/bin/$CPU$OSREL
For clients that are running Version 5.6 of the operating system, export the following file
systems:
■
For SPARC clients – Export /export/local/bin/sparc5.6.
Chapter 4 • Administering Autofs
105
How to Replicate Shared Files Across Several Servers
■
For x86 clients – Place executables in /export/local/bin/i3865.6.
How to Replicate Shared Files Across Several
Servers
The best way to share replicated file systems that are read-only is to use failover. For more
information about failover, see “Client-Side Failover” on page 41.
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
In the autofs maps, create a comma-separated list of all replica servers.
For example:
bin
aa,bb,cc,dd:/export/local/bin/$CPU
Autofs chooses the nearest server. If a server has several network interfaces, list each interface.
Autofs chooses the nearest interface to the client, avoiding unnecessary routing of NFS traffic.
Autofs Security Restrictions
The nosuid option prevents users from creating files with the setuid or setgid bit set.
This entry overrides the entry for /home in a generic local /etc/auto_master file. For
information about the generic local /etc/auto_masterfile, see “Setting Up a Common View
of /home” on page 100. The override happens because the +auto_master reference to
the external name service map occurs before the /home entry in the file. If the entries in the
auto_home map include mount options, the nosuid option is overwritten. Therefore, either no
options should be used in the auto_home map or the nosuid option must be included with each
entry.
Note - Do not mount the home directory disk partitions on or under /home on the server.
How to Apply Autofs Security Restrictions
1.
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Become an administrator.
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
How to Use a Public File Handle With Autofs
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Create a -nosuid entry in the name service auto_master file.
/home
auto_home
-nosuid
How to Use a Public File Handle With Autofs
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Create the following entry in the autofs map.
/usr/local
-ro,public
bee:/export/share/local
The public option forces the public handle to be used. If the NFS server does not support a
public file handle, the mount fails.
How to Use NFS URLs With Autofs
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Create the following entry in the autofs map.
/usr/local
-ro
nfs://server-name/export/share/local
The service tries to use the public file handle on the NFS server. However, if the server does not
support a public file handle, the MOUNT protocol is used.
Disabling Autofs Browsability
The default version of /etc/auto_master that is installed has the -nobrowse option added to
the entries for /home and /net. In addition, the upgrade procedure adds the -nobrowse option
to the /home and /net entries in /etc/auto_master if these entries have not been modified.
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107
How to Completely Disable Autofs Browsability on a Single NFS Client
However, you might have to make these changes manually or to turn off browsability for sitespecific autofs mount points after the installation.
This section describes how to turn off the browsability feature for a single client, all clients, and
a selected file system.
How to Completely Disable Autofs Browsability on a Single
NFS Client
1.
Become an administrator on the NFS client.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Change the autofs SMF configuration parameter.
$ sharectl set -p nobrowse=TRUE autofs
3.
Restart the autofs service.
$ svcadm restart system/filesystem/autofs
How to Disable Autofs Browsability for All Clients
To disable browsability for all clients, you must employ a name service such as NIS.
Otherwise, you need to manually edit the automounter maps on each client. In this example, the
browsability of the /home directory is disabled. You must follow this procedure for each indirect
autofs node that needs to be disabled.
1.
Add the -nobrowse option to the /home entry in the name service auto_master file.
/home
2.
auto_home
-nobrowse
Run the automount command on all clients to make the new behaviour effective.
The new behavior also becomes effective after a reboot.
$ /usr/sbin/automount
How to Disable Autofs Browsability on a Selected File System
In this example, browsability of the /net directory is disabled. You can use the same procedure
for /home or any other autofs mount points.
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How to Disable Autofs Browsability on a Selected File System
1.
Verify the search order for the automount naming services.
The config/automount property in the name-service/switch service shows the search order
for the automount information.
$ svcprop -p config svc:/system/name-service/switch
config/value_authorization astring solaris.smf.value.name-service.switch
config/printer astring user\ files
config/default astring files\ nis
config/automount astring files\ nis
The last entry shows that local automount files are searched first and then the NIS service is
checked. The config/default entry specifies the search order for all naming information
not specifically listed. If you are using the LDAP naming service, the config/automount
property in the name-service/switch service shows ldap in the search order for the automount
information.
$ svcprop -p config svc:/system/name-service/switch
config/value_authorization astring solaris.smf.value.name-service.switch
config/printer astring user\ files\ ldap
config/default astring files\ ldap
config/automount astring files\ ldap
2.
Check the position of the +auto_master entry in /etc/auto_master.
For additions to the local files to have precedence over the entries in the namespace, the
+auto_master entry must be moved to follow /net.
# Master map for automounter
#
/net
-hosts
-nosuid
/home auto_home
/nfs4
-fedfs
-ro,nosuid,nobrowse
+auto_master
A standard configuration places the +auto_master entry at the top of the file, which prevents
any local changes from being used.
3.
Add the nobrowse option to the /net entry in the /etc/auto_master file.
/net
4.
-hosts
-nosuid,nobrowse
On all clients, run the automount command.
The new behavior becomes effective after running the automount command on the client
systems or after a reboot.
$ /usr/sbin/automount
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Managing Network File Systems in Oracle Solaris 11.3 • October 2017
♦ ♦ ♦
5
C H A P T E R
5
Commands for Managing Network File Systems
This chapter describes the command-line utilities that are used to manage network file systems.
For a quick reference to commonly used commands for NFS file sharing and troubleshooting,
see Appendix A, “NFS File Sharing Command Reference”.
This chapter contains the following topics:
■
■
“NFS Commands” on page 111
“FedFS Commands” on page 132
Note - If your system has zones enabled and you want to use this feature in a non-global zone,
see Introduction to Oracle Solaris Zones.
NFS Commands
These commands must be run as root to be fully effective, but requests for information can be
made by all users:
■
“automount Command” on page 112
■
“clear_locks Command” on page 113
■
“fsstat Command” on page 113
■
“mount Command” on page 114
■
“mountall Command” on page 121
■
“nfsref Command” on page 132
■
“sharectl Command” on page 122
■
“share Command” on page 124
■
“shareall Command” on page 130
■
“showmount Command” on page 130
■
“umount Command” on page 120
Chapter 5 • Commands for Managing Network File Systems
111
NFS Commands
■
■
■
“umountall Command” on page 121
“unshare Command” on page 129
“unshareall Command” on page 130
In addition, commands associated with the FedFS service are covered in “FedFS
Commands” on page 132.
automount Command
This command installs autofs mount points and associates the information in the automaster
files with each mount point. The syntax of the command is as follows:
automount [-t duration] [-v]
-t duration
Sets the time, in seconds, that a file system is to remain mounted.
-v
Selects the verbose mode. Running this command in verbose mode
enables easier troubleshooting.
If not specifically set, the value for duration is set to 5 minutes. In most circumstances, this
value is good. However, on systems that have many automounted file systems, you might need
to increase the duration value. In particular, if a server has many users active, checking the
automounted file systems every 5 minutes can be inefficient. Checking the autofs file systems
every 1800 seconds, which is 30 minutes, could be more optimal. By not unmounting the file
systems every 5 minutes, /etc/mnttab can become large. To reduce the output when df checks
each entry in /etc/mnttab, you can filter the output from df by using the -F option (see the
df(1M) man page) or by using egrep.
You should consider that adjusting the duration also changes how quickly changes to the
automounter maps are reflected. Changes cannot be seen until the file system is unmounted.
Refer to “Modifying the Maps” on page 98 for instructions on how to modify automounter
maps.
You can make the same specifications with the sharectl command that you would make on the
command line. However, unlike the command-line options, the SMF repository preserves your
specifications, through service restarts and system reboots, as well as system upgrades. You can
set the following parameters for the automount command.
timeout
Sets the duration for a file system to remain idle before the file system is unmounted. This
keyword is the equivalent of the -t argument for the automount command. The default
value is 600.
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automount_verbose
Provides notification of autofs mounts, unmounts, and other nonessential events. This
keyword is the equivalent of the -v argument for automount. The default value is FALSE.
clear_locks Command
This command enables you to remove all file, record, and share locks for an NFS client.
You must be root to run this command. From an NFS server, you can clear the locks for a
specific client. From an NFS client, you can clear locks for that client on a specific server. The
following example would clear the locks for an NFS client named tulip on the current system.
$ clear_locks tulip
Use the -s option to specify which NFS host to clear the locks from. You must run this option
from the NFS client that created the locks. In this situation, the locks from the client would be
removed from an NFS server named bee.
$ clear_locks -s bee
Caution - This command should be run only when a client crashes and cannot clear its locks. To
avoid data corruption problems, do not clear locks for an active client.
fsstat Command
The fsstat utility enables you to monitor file system operations by file system type and by
mount point. Various options enable you to customize the output:
-i
Displays statistics about the I/O operations for mount points
-n
Displays statistics about the naming operations for mount points
The following example shows output for NFS Version 3, NFS Version 4, and the root mount
point.
$ fsstat nfs3 nfs4 /
new
name name
file
remov chng
3.81K
90 3.65K
nfs3
attr
get
5.89M
attr
set
11.9K
lookup
ops
35.5M
rddir
ops
26.6K
read read
ops bytes
109K 118M
write
ops
35.0K
write
bytes
8.16G
Chapter 5 • Commands for Managing Network File Systems
113
NFS Commands
759
nfs4
25.2K
503
457
93.6K
1.44K
454K
8.82K 65.4K
827M
292
18.1K 1.12K
54.7M
1017
259M
1.76M 22.4M 20.1G
1.43M
223K
3.77G /
The following example uses the -i option to provide statistics about the I/O operations for NFS
Version 3, NFS Version 4, and the root mount point.
$ fsstat -i nfs3
read
read
ops bytes
109K
118M
65.4K
827M
22.4M 20.1G
nfs4 /
write
ops
35.0K
292
1.43M
write
bytes
8.16G
223K
3.77G
rddir
ops
26.6K
8.82K
1.76M
rddir
bytes
4.45M
2.62M
3.29G
rwlock
ops
170K
74.1K
25.5M
rwulock
ops
170K nfs3
74.1K nfs4
25.5M /
The following example uses the -n option to provide statistics about the naming operations for
NFS Version 3, NFS Version 4, and the root mount point.
$ fsstat
lookup
35.5M
454K
259M
-n nfs3 nfs4 /
creat remov link
3.79K
90
2
403
503
0
25.2K 18.1K 114
renam mkdir rmdir
3.64K
5
0
101
0
0
1017
10
2
rddir symlnk rdlnk
26.6K
11 136K nfs3
8.82K
356 1.20K nfs4
1.76M
12 8.23M /
For more information, see the fsstat(1M) man page.
mount Command
With this command, you can attach a named file system, either local or remote, to a specified
mount point. For more information, see the mount(1M) man page. Used without arguments,
mount displays a list of file systems that are currently mounted on your computer.
Each file system type included in the standard Oracle Solaris installation has specific options
for the mount command. For NFS file systems options, see the mount_nfs(1M) man page. For
UFS file system options, see the mount_ufs(1M) man page.
You can select a path name to mount from an NFS server by using an NFS URL instead of the
standard server:/pathname syntax. See “How to Mount an NFS File System by Using an NFS
URL” on page 79 for further information.
Caution - The mount command does not warn about invalid options. The command silently
ignores any options that cannot be interpreted. Ensure that you verify all of the options that
were used so that you can prevent unexpected behavior.
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mount Options for NFS File Systems
This section describes some of the options that can follow the -o flag when you are mounting an
NFS file system. For a complete list of options, refer to the mount_nfs(1M) man page.
bg|fg
These options can be used to select the retry behavior if a mount fails. The bg option causes
the mount attempts to be run in the background. The fg option causes the mount attempt to
be run in the foreground. The default is fg, which is the best selection for file systems that
must be available because it prevents further processing until the mount is complete. bg is a
good selection for noncritical file systems because the client can do other processing while
waiting for the mount request to be completed.
forcedirectio
This option improves performance of large sequential data transfers. Data is copied directly
to a user buffer. No caching is performed in the kernel on the client. This option is off by
default (noforcedirectio).
To permit an application to issue concurrent writes, as well as concurrent reads and writes,
to a single file on the client, use the forcedirectio mount option. This option, enables
this functionality for all files within the mounted file system. You could also enable this
functionality on a single file on the client by using the directio() interface. Unless this
functionality has been enabled, writes to files are serialized. Also, if concurrent writes
or concurrent reads and writes are occurring, then POSIX semantics are no longer being
supported for that file.
For an example of how to use this option, refer to “Using the mount
Command” on page 117.
largefiles
With this option, you can access files that are larger than 2 Gbytes. Whether a large file
can be accessed can only be controlled on the server, so this option is silently ignored on
NFS Version 3 mounts. By default, all UFS file systems are mounted with largefiles. For
mounts that use the NFS Version 2 protocol, the largefiles option causes the mount to
fail with an error.
nolargefiles
This option for UFS mounts guarantees that no large files can exist on the file system.
Because the existence of large files can be controlled only on the NFS server, no option for
nolargefiles exists when using NFS mounts. Attempts to NFS-mount a file system by
using this option are rejected with an error.
Chapter 5 • Commands for Managing Network File Systems
115
NFS Commands
nosuid|suid
The nosuid option is the equivalent of specifying the nodevices option with the nosetuid
option. When the nodevices option is specified, the opening of device-special files on the
mounted file system is disallowed. When the nosetuid option is specified, the setuid bit
and setgid bit in binary files that are located in the file system are ignored. The processes
run with the privileges of the user who executes the binary file.
The suid option is the equivalent of specifying the devices option with the setuid option.
When the devices option is specified, the opening of device-special files on the mounted
file system is allowed. When the setuid option is specified, the setuid bit and the setgid
bit in binary files that are located in the file system are honored by the kernel.
If neither option is specified, the default option is suid, which provides the default
behavior of specifying the devices option with the setuid option.
The following table describes the effect of combining nosuid or suid with devices or
nodevices, and setuid or nosetuid. Note that in each combination of options, the most
restrictive option determines the behavior.
Behavior From the Combined Options
Option
Option
Option
The equivalent of nosetuid with
nodevices
nosuid
nosetuid
nodevices
The equivalent of nosetuid with
nodevices
nosuid
nosetuid
devices
The equivalent of nosetuid with
nodevices
nosuid
setuid
nodevices
The equivalent of nosetuid with
nodevices
nosuid
setuid
devices
The equivalent of nosetuid with
nodevices
suid
nosetuid
nodevices
The equivalent of nosetuid with devices
suid
nosetuid
devices
The equivalent of setuid with nodevices
suid
setuid
nodevices
The equivalent of setuid with devices
suid
setuid
devices
The nosuid option provides additional security for NFS clients that access potentially
untrusted servers. Mounting remote file systems with this option reduces the chance of
privilege escalation through importing untrusted devices or importing untrusted setuid
binary files. All these options are available in all Oracle Solaris file systems.
public
This option forces the use of the public file handle when contacting the NFS server. If the
public file handle is supported by the server, the mounting operation is faster because the
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NFS Commands
MOUNT protocol is not used. Also, because the MOUNT protocol is not used, the public
option allows mounting to occur through a firewall.
rw|ro
The -rw and -ro options indicate whether a file system is to be mounted read-write or readonly. The default is read-write, which is the appropriate option for remote home directories,
mail-spooling directories, or other file systems that need to be changed by users. The readonly option is appropriate for directories that should not be changed by users. For example,
shared copies of the man pages should not be writable by users.
sec=mode
You can use this option to specify the authentication mechanism to be used during the
mount transaction. The available values for mode are:
■
krb5 for Kerberos Version 5 authentication service
■
krb5i for Kerberos Version 5 with integrity
■
krb5p for Kerberos Version 5 with privacy
■
none for no authentication
■
dh for Diffie-Hellman (DH) authentication
■
sys for standard UNIX authentication
The modes are also defined in /etc/nfssec.conf.
soft|hard
An NFS file system that is mounted with the soft option returns an error if the server
does not respond. The hard option causes the mount to continue to retry until the server
responds. The default is hard, which should be used for most file systems. Applications
frequently do not check return values from soft-mounted file systems, which can make
the application fail or can lead to corrupted files. If the application does check the return
values, routing problems and other conditions can still confuse the application or lead to
file corruption. In most situations, the soft option should not be used. If a file system is
mounted by using the hard option and becomes unavailable, an application that uses this
file system hangs until the file system becomes available.
Using the mount Command
The following examples show different scenario:
■
In NFS Version 2 or NFS Version 3, both of the following commands mount an NFS file
system from the server bee read-only.
$ mount -F nfs -r bee:/export/share/man /usr/man
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$ mount -F nfs -o ro bee:/export/share/man /usr/man
In NFS Version 4, the following command line would accomplish the same mount.
$ mount -F nfs -o vers=4 -r bee:/export/share/man /usr/man
■
In NFS Version 2 or NFS Version 3, the -O option in the following command forces the man
pages from the server bee to be mounted on the local system even if /usr/man has already
been mounted.
$ mount -F nfs -O bee:/export/share/man /usr/man
In NFS Version 4, the following command would accomplish the same mount:
$ mount -F nfs -o vers=4 -O bee:/export/share/man /usr/man
■
In NFS Version 2 or NFS Version 3, the following command uses client failover.
$ mount -F nfs -r bee,wasp:/export/share/man /usr/man
In NFS Version 4, the following command uses client failover.
$ mount -F nfs -o vers=4 -r bee,wasp:/export/share/man /usr/man
Note - When used from the command line, the listed servers must support the same version
of the NFS protocol. Do not use both NFS Version 2 and NFS Version 3 servers when
running mount from the command line. You can use both servers with autofs because
autofs automatically selects the best subset of NFS Version 2 or NFS Version 3 servers.
■
The following example shows how to use an NFS URL with the mount command in NFS
Version 2 or NFS Version 3.
$ mount -F nfs nfs://bee//export/share/man /usr/man
The following example shows how to use an NFS URL with the mount command in NFS
Version 4.
$ mount -F nfs -o vers=4 nfs://bee//export/share/man /usr/man
■
The following example shows how to use the quota mount option to enable the user to
check the file system disk quota and usage.
$ mount -F nfs -o quota bee:/export/share/man /usr/man
■
The following example shows how to use the forcedirectio mount option to enable the
client to permit concurrent writes, as well as concurrent reads and writes, to a file.
$ mount -F nfs -o forcedirectio bee:/home/somebody /mnt
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In this example, the command mounts an NFS file system from the server bee and enables
concurrent reads and writes for each file in the directory /mnt. When support for concurrent
reads and writes is enabled, the following occurs.
■
■
The client permits applications to write to a file in parallel.
Caching is disabled on the client. Consequently, data from reads and writes is kept on
the server. More explicitly, because the client does not cache the data that is read or
written, any data that the application does not already have cached for itself is read from
the server. The client's operating system does not have a copy of this data. Normally, the
NFS client caches data in the kernel for applications to use.
Because caching is disabled on the client, the read-ahead and write-behind processes
are disabled. A read-ahead process occurs when the kernel anticipates the data that an
application might request next. The kernel then starts the process of gathering that data
in advance. The kernel's goal is to have the data ready before the application makes a
request for the data.
The client uses the write-behind process to increase write throughput. Instead of
immediately starting an I/O operation every time an application writes data to a file, the
data is cached in memory. Later, the data is written to the disk.
■
Potentially, the write-behind process permits the data to be written in larger chunks
or to be written asynchronously from the application. Typically, the result of using
larger chunks is increased throughput. Asynchronous writes permit overlap between
application processing and I/O processing. Also, asynchronous writes permit the storage
subsystem to optimize the I/O by providing a better sequencing of the I/O. Synchronous
writes force a sequence of I/O on the storage subsystem that might not be optimal.
Significant performance degradation can occur if the application is not prepared to
handle the semantics of data that is not being cached. Multithreaded applications avoid
this problem.
Note - If support for concurrent writes is not enabled, all write requests are serialized. When
a write request is in progress, a second write request has to wait for the first write request to
be completed before proceeding.
■
The following example shows how to use the mount command with no arguments to display
file systems that are mounted on a client.
$ mount
/ on /dev/dsk/c0t3d0s0 read/write/setuid on Wed Apr 7 13:20:47 2004
/usr on /dev/dsk/c0t3d0s6 read/write/setuid on Wed Apr 7 13:20:47 20041995
/proc on /proc read/write/setuid on Wed Apr 7 13:20:47 2004
/dev/fd on fd read/write/setuid on Wed Apr 7 13:20:47 2004
/tmp on swap read/write on Wed Apr 7 13:20:51 2004
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/opt on /dev/dsk/c0t3d0s5 setuid/read/write on Wed Apr 7 13:20:51 20041995
/home/kathys on bee:/export/home/bee7/kathys
intr/noquota/nosuid/remote on Wed Apr 24 13:22:13 2004
umount Command
The umount command enables you to remove a remote file system that is currently mounted.
You can use the following options with the umount command:
-V
Enables testing
-a
Unmounts several file systems at one time. If mount-points are included
with the -a option, those file systems are unmounted. If no mount points
are included, an attempt is made to unmount all file systems that are
listed in /etc/mnttab except for the “required” file systems, such as /,
/usr, /var, /proc, /dev/fd, and /tmp. Because the file system is already
mounted and should have an entry in /etc/mnttab, you do not need to
include a flag for the file system type.
-f
Forces a busy file system to be unmounted. You can use this option to
unhang a client that is hung while trying to mount an unmountable file
system.
Caution - By forcing an unmount of a file system, you can cause data loss if files are being
written to that system.
EXAMPLE 8
Unmounting a File System
The following example unmounts a file system that is mounted on /usr/man:
$ umount /usr/man
EXAMPLE 9
Using Options with umount
The following example displays the results of running umount -a -V:
$ umount -a -V
umount /home/kathys
umount /opt
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umount /home
umount /net
Note that this command does not actually unmount the file systems.
mountall Command
Use the mountall command to mount all file systems or a specific group of file systems that are
listed in a file system table. The command provides the following options:
-F FSType
Selects the file system type to be accessed
-r
Selects all the remote file systems that are listed in a file system table
-l
Selects all the local file systems
Because all file systems that are labeled as NFS file system type are remote file systems, some
of these options are redundant. For more information, see the mountall(1M) man page.
The following two examples of user input are equivalent:
$ mountall -F nfs
$ mountall -F nfs -r
umountall Command
Use the umountall command to unmount a group of file systems. You can use the following
options with the umountall command:
-k
Runs the fuser -k mount-point command to kill any processes that are
associated with the mount-point
-s
Indicates that unmount is not to be performed in parallel
-l
Specifies that only local file systems are to be used
-r
Specifies that only remote file systems are to be used
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-h host
Specifies that all file systems from the named host should be unmounted.
You cannot combine the -h option with -l or -r.
The following example unmounts all file systems that are mounted from remote hosts:
$ umountall -r
The following example unmounts all file systems that are currently mounted from the server
bee:
$ umountall -h bee
sharectl Command
This release includes the sharectl utility, which is an administrative tool that enables you to
configure and manage file-sharing protocols such as NFS. You can use this command to do the
following:
■
■
■
Set client and server operational properties
Display property values for a specific protocol
Obtain the status of a protocol
The sharectl utility uses the following syntax:
$ sharectl subcommand [option] [protocol]
The sharectl utility supports the following subcommands:
set
Defines the properties for a file-sharing protocol. For a list of properties
and property values, see the parameters described in the nfs(4) man
page.
get
Displays the properties and property values for the specified protocol.
status
Displays whether the specified protocol is enabled or disabled. If no
protocol is specified, the status of all file-sharing protocols is displayed.
For more information about the sharectl utility, see the following:
122
■
sharectl(1M) man page
■
“set Subcommand” on page 123
■
“get Subcommand” on page 123
■
“status Subcommand” on page 124
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set Subcommand
The set subcommand, which defines the properties for a file-sharing protocol, supports the
following options:
-h
Provides an online-help description
-p
Defines a property for the protocol
The set subcommand uses the following syntax:
$ sharectl set [-h] [-p property=value] protocol
You must have root privileges to use the set subcommand.
You do not need to repeat this command for each additional property value. You can use the -p
option multiple times to define multiple properties in the same command.
The following example sets the minimum version of the NFS protocol for the client to 3:
$ sharectl set -p client_versmin=3 nfs
The following example shows how to require clients to use reserved ports for NFS calls for all
file systems shared with AUTH_SYS:
$ sharectl set -p resvport=on nfs
get Subcommand
The get subcommand, which displays the properties and property values for the specified
protocol, supports the following options:
-h
Provides an online-help description.
-p
Identifies the property value for the specified property. If the -p option is
not used, all property values are displayed.
The get subcommand uses the following syntax:
$ sharectl get [-h] [-p property] protocol
You must have root privileges to use the get subcommand.
The following example uses servers, which is the property that enables you to specify the
maximum number of concurrent NFS requests:
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$ sharectl get -p servers nfs
servers=1024
In the following example, because the -p option is not used, all property values are displayed:
$ sharectl get nfs
servers=1024
listen_backlog=32
protocol=ALL
servers=32
lockd_listen_backlog=32
lockd_servers=20
lockd_retransmit_timeout=5
grace_period=90
nfsmapid_domain=example.com
server_versmin=2
server_versmax=4
client_versmin=2
client_versmax=4
server_delegation=on
max_connections=-1
device=
status Subcommand
The status subcommand displays whether the specified protocol is enabled or disabled. It
supports the -h option, which provides an online-help description.
The status subcommand uses the following syntax:
$ sharectl status [-h] [protocol]
The following example shows the status of the NFS protocol:
$ sharectl status nfs
nfs
enabled
share Command
Use the share command to make a local file system on an NFS server available for mounting.
You can also use the share command to display a list of the file systems on your system that are
currently shared. The NFS server must be running for the share command to work.
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The objects that can be shared include any directory tree. However, each file system hierarchy
is limited by the disk slice or partition that the file system is located on.
A file system cannot be shared if that file system is part of a larger file system that is already
being shared. For example, if /usr and /usr/local are on one disk slice, /usr can be shared or
/usr/local can be shared. However, if both directories need to be shared with different share
options, /usr/local must be moved to a separate disk slice.
You can gain access to a file system that is read-only shared through the file handle of a file
system that is read-write shared. However, the two file systems have to be on the same disk
slice. To create a more secure situation, place those file systems that need to be read-write on
a separate partition or separate disk slice from the file systems that you need to share as readonly.
Note - For information about how NFS Version 4 functions when a file system is unshared and
then reshared, refer to “Unsharing and Resharing a File System in NFS Version 4” on page 29.
share Options
Some of the options that you can include with the -o flag are as follows:
rw|ro
The pathname file system is shared read-write or read-only for all clients.
rw=access-list
The file system is shared read-write for the clients that are listed only. All other requests
are denied. See “Setting Access Lists With the share Command” on page 128 for more
information. You can use this option to override an -ro option.
NFS-Specific share Options
The options that you can use with NFS file systems include the following:
aclok
This option enables an NFS server that supports the NFS Version 2 protocol to be
configured to do access control for NFS Version 2 clients. Without this option, all clients
are given minimal access. With this option, the clients have maximal access. For instance,
on file systems that are shared with the aclok option, if anyone has read permissions,
everyone does. However, without this option, you can deny access to a client who should
have access permissions. A decision to permit too much access or too little access depends
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on the security systems already in place. See “Using Access Control Lists to Protect
UFS Files” in Securing Files and Verifying File Integrity in Oracle Solaris 11.3 for more
information about access control lists (ACLs).
Note - To use ACLs, ensure that clients and servers run software that supports the NFS Version
3 and NFS_ACL protocols. If the software only supports the NFS Version 3 protocol, clients
obtain correct access but cannot manipulate the ACLs. If the software supports the NFS_ACL
protocol, the clients obtain correct access and can manipulate the ACLs.
anon=uid
You use anon to select the user ID of unauthenticated users. If you set anon to -1, the server
denies access to unauthenticated users. Because granting root access by setting anon=0
allows unauthenticated users to have root access, use the root option instead.
index=filename
When a user accesses an NFS URL, the index=filename option forces the HTML file to
load instead of displaying a list of the directory. This option mimics the action of current
browsers if an index.html file is found in the directory that the HTTP URL is accessing.
This option is the equivalent of setting the DirectoryIndex option for httpd. For instance,
suppose that share command reports the following:
export_web /export/web
nfs sec=sys,public,index=index.html,ro
These URLs then display the same information:
nfs://server/dir
nfs://server/dir/index.html
nfs://server//export/web/dir
nfs://server//export/web/dir/index.html
http://server/dir
http://server/dir/index.html
log=tag
This option specifies the tag in /etc/nfs/nfslog.conf that contains the NFS server
logging configuration information for a file system. This option must be selected to enable
NFS server logging.
nosuid
This option signals that all attempts to enable the setuid or setgid mode should be
ignored. NFS clients cannot create files with the setuid or setgid bits on.
public
The public option has been added to the share command to enable WebNFS browsing.
Only one file system on a server can be shared with this option.
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root=access-list
The server gives root access to the hosts in the list. By default, the server does not give root
access to any remote hosts. If the selected security mode is anything other than sec=sys,
you can only include client host names in the list. See “Setting Access Lists With the share
Command” on page 128 for more information.
Caution - Granting root access to other hosts has wide security implications. Use the -root=
option with extreme caution.
root=client-name
The client-name value is used with AUTH_SYS authentication to check the client's IP address
against a list of addresses provided by exportfs(1B). If a match is found, root access is
given to the file systems being shared.
root=hostname
For secure NFS modes such as AUTH_SYS or RPCSEC_GSS, the server checks the clients'
principal names against a list of host-based principal names that are derived from an access
list. The generic syntax for the client's principal name is root@hostname. For Kerberos V,
the syntax is root/hostname.fully.qualified@REALM. When you use the hostname value, the
clients on the access list must have the credentials for a principal name. For Kerberos V, the
client must have a valid keytab entry for its root/hostname.fully.qualified@REALM principal
name. For more information, see “Configuring Kerberos Clients” in Managing Kerberos
and Other Authentication Services in Oracle Solaris 11.3.
sec=mode[:mode]
This option sets the security modes that are needed to obtain access to the file system.
By default, the security mode is UNIX authentication. You can specify multiple modes,
but use each security mode only once per command line. Each sec= option applies to any
subsequent rw, ro, rw=, ro=, root=, and window= options until another sec= is encountered.
The use of -sec=none maps all users to user nobody.
window=value
value selects the maximum lifetime in seconds of a credential on the NFS server. The
default value is 30000 seconds or 8.3 hours.
resvport
This option enforces the use of reserved port for individual file systems.
The following example shows how to require the client to use reserved port for an NFS share
that is shared with AUTH_SYS:
$ share -F NFS -o resvport=on /usr/src
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Setting Access Lists With the share Command
The access list that you provide with the share command can include a domain name, a subnet
number, or an entry to deny access, as well as the standard -ro=, -rw=, or -root= options. These
extensions should simplify file access control on a single server without having to change the
namespace or maintain long lists of clients.
The following example provides read-only access for most systems but allows read-write access
for rose and lilac:
$ share -F nfs -o ro,rw=rose:lilac /usr/src
The following example assigns read-only access to any host in the eng netgroup. The client
rose is specifically given read-write access.
$ share -F nfs -o ro=eng,rw=rose /usr/src
Note - You cannot specify both rw and ro without arguments. If no read-write option is
specified, the default is read-write for all clients.
To share one file system with multiple clients, you must type all options on the same line. If you
issue multiple invocations of the share command on the same object, only the last command
that is run is applied. The following example enables read-write access to three client systems,
but only rose and tulip are given access to the file system as root.
$ share -F nfs -o rw=rose:lilac:tulip,root=rose:tulip /usr/src
When sharing a file system that uses multiple authentication mechanisms, ensure that you
include the -ro, -ro=, -rw, -rw=, -root, and -window options after the correct security modes. In
this example, UNIX authentication is selected for all hosts in the netgroup that is named eng.
These hosts can mount the file system only in read-only mode. The hosts tulip and lilac can
mount the file system read-write if these hosts use Diffie-Hellman authentication. With these
options, tulip and lilac can mount the file system read-only even if these hosts are not using
DH authentication. However, the host names must be listed in the eng netgroup.
$ share -F nfs -o sec=dh,rw=tulip:lilac,sec=sys,ro=eng /usr/src
Even though UNIX authentication is the default security mode, UNIX authentication is not
included if the -sec option is used. Therefore, you must include a -sec=sys option if UNIX
authentication is to be used with any other authentication mechanism.
You can use a DNS domain name in the access list by preceding the actual domain name with
a dot. The string that follows the dot is a domain name, not a fully qualified host name. The
following example allows mount access to all hosts in the eng.example.com domain:
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$ share -F nfs -o ro=.:.eng.example.com /export/share/man
In this example, the single dot matches all hosts that are matched through the NIS namespace.
The results that are returned from these name services do not include the domain name. The
.eng.example.com entry matches all hosts that use DNS for namespace resolution. Because
DNS always returns a fully qualified host name, the longer entry is required if you use a
combination of DNS and the other namespaces.
You can use a subnet number in an access list by preceding the actual network number or
the network name with an at (@) sign. This character differentiates the network name from a
netgroup or a fully qualified host name. You must identify the subnet in either /etc/networks
or in an NIS namespace. The following entries have the same effect if the 192.0.2 subnet has
been identified as the eng network:
$ share -F nfs -o ro=@eng /export/share/man
$ share -F nfs -o ro=@192.0.2 /export/share/man
$ share -F nfs -o ro=@192.0.2.0 /export/share/man
The last two entries show that you do not need to include the full network address.
If the network prefix is not byte aligned, as with Classless Inter-Domain Routing (CIDR),
the mask length can be explicitly specified on the command line. The mask length is defined
by following either the network name or the network number with a slash and the number of
significant bits in the prefix of the address. For example:
$ share -f nfs -o ro=@eng/23 /export/share/man
$ share -F nfs -o ro=@192.0.2/23 /export/share/man
In these examples, the “/17” indicates that the first 17 bits in the address are to be used as the
mask. For additional information about CIDR, see RFC 1519.
You can also select negative access by placing a “-” before the entry. Note that the entries are
read from left to right. Therefore, you must place the negative access entries before the entry
that the negative access entries apply to:
$ share -F nfs -o ro=-rose:.eng.example.com /export/share/man
This example would allow access to any hosts in the eng.example.com domain except the host
that is named rose.
unshare Command
The unshare command enables you to make a previously available file system unavailable for
mounting by clients. When you unshare an NFS file system, access from clients with existing
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mounts is inhibited. The file system might still be mounted on the client but the files are not
accessible. The unshare command deletes the share permanently unless the -t option is used to
temporarily unshare the file system.
Note - For information about how NFS Version 4 functions when a file system is unshared and
then reshared, refer to “Unsharing and Resharing a File System in NFS Version 4” on page 29.
The following example unshares the file system /usr/src:
$ unshare /usr/src
shareall Command
The shareall command enables the sharing of multiple file systems. When used with no
options, the command shares all entries in the SMF repository. You can include a file name to
specify the name of a file that lists share command lines.
The following example shares all file systems that are listed in a local file:
$ shareall /etc/dfs/special_dfstab
unshareall Command
The unshareall command makes all currently shared resources unavailable. The -F FSType
option selects a list of file system types that are defined in /etc/dfs/fstypes. This flag enables
you to choose only certain types of file systems to be unshared. The default file system type is
defined in /etc/dfs/fstypes. To choose specific file systems, use the unshare command.
The following example unshares all NFS-type file systems:
$ unshareall -F nfs
showmount Command
Use the showmount command to display the following information:
■
■
130
All clients that have remotely mounted file systems that are shared from an NFS server
Only the file systems that are mounted by clients
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■
Shared file systems with client access information
Note - The showmount command shows only NFS Version 2 and Version 3 exports. This
command does not show NFS Version 4 exports.
The command syntax is as follows:
showmount [-ade] [hostname]
-a
Prints a list of all the remote mounts. Each entry includes the client name
and the directory.
-d
Prints a list of the directories that are remotely mounted by clients.
-e
Prints a list of the files that are shared or are exported.
hostname
Selects the NFS server to gather the information from.
If hostname is not specified, the local host is queried.
The following example lists all clients and the local directories that the clients have mounted:
$ showmount -a bee
lilac:/export/share/man
lilac:/usr/src
rose:/usr/src
tulip:/export/share/man
The following example lists the directories that have been mounted:
$ showmount -d bee
/export/share/man
/usr/src
The following example lists file systems that have been shared:
$ showmount -e bee
/usr/src
(everyone)
/export/share/man
eng
The nfs_props/showmount_info property of the /network/nfs/server:default service
controls how much information is displayed to a client by the showmount command. The default
value is full. If this value is set to none then the client will see only those remote file systems
on the server that the client can mount. No information about other clients is displayed. See
Example 5, “Restricting File System Information Displayed to Clients,” on page 80 for an
example of how to change this property.
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nfsref Command
Use the nfsref command to add, delete, or list NFSv4 referrals. The command syntax is as
follows:
nfsref add path location [location...]
nfsref remove path
nfsref lookup path
path
Determines the name for the reparse point.
location
Identifies one or more NFS or SMB shared file systems to be associated
with the reparse point.
FedFS Commands
The following commands are associated with the FedFS service:
nsdb-list
Lists all FedFS data stored in the LDAP server.
nsdb-nces
Lists the naming contexts on the LDAP server and the relative
distinguished name.
nsdb-resolve-fsn
Shows the fileset location for the selected fileset name.
nsdb-update-nci
Manages distinguished names for FedFS data.
nsdbparams
Manages FedFS connections.
For examples of how these commands are used, see “Administering FedFS” on page 91.
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6
C H A P T E R
6
Troubleshooting Network File Systems
This chapter provides information about NFS troubleshooting strategies, procedures, and
commands. This chapter also includes information about troubleshooting autofs and a list of
the NFS error messages with their meanings.
This chapter contains the following topics:
■
■
■
■
■
“Strategies for NFS Troubleshooting” on page 133
“Commands for Troubleshooting NFS Problems” on page 134
“NFS Troubleshooting Procedures” on page 140
“Troubleshooting Autofs” on page 146
“NFS Error Messages” on page 150
Strategies for NFS Troubleshooting
When tracking an NFS problem, remember the main points of possible failure: the NFS server,
the NFS client, and the network. Try to isolate each component to find the one that is not
working. The mountd and nfsd daemons must always be running on the server for remote
mounts to succeed.
The -intr option is set by default for all mounts. If a program hangs with a server not
responding message, you can terminate the program with the keyboard interrupt Control-C.
When the network or server has problems, programs that access hard-mounted remote files
fail differently than programs that access soft-mounted remote files. Hard-mounted remote
file systems cause the client's kernel to retry the requests until the server responds again. Softmounted remote file systems cause the client's system calls to return an error after several
attempts. Avoid soft mounting because the errors can result in unexpected application errors and
data corruption.
When a file system is hard mounted, a program that tries to access the file system hangs if the
server fails to respond. In this situation, the NFS system displays the following message on the
console:
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NFS server hostname not responding still trying
When the server finally responds, the following message appears on the console:
NFS server hostname ok
A program that accesses a soft-mounted file system whose server is not responding generates
the following message:
NFS operation failed for server hostname: error # (error-message)
Caution - Because of possible errors, do not soft-mount file systems with read-write data or
file systems from which executables are run. Writable data could be corrupted if the application
ignores the errors. Mounted executables might not load properly and can fail.
Commands for Troubleshooting NFS Problems
This section describes the commands you can use for troubleshooting NFS problems.
nfsstat Command
This command displays statistical information about NFS and RPC connections. Use the
following syntax to display NFS server and client statistics:
nfsstat [-cmnrsz]
-c
Displays client-side information.
-m
Displays statistics for each NFS-mounted file system.
-n
Displays the NFS information on both the client side and the server side.
-r
Displays RPC statistics.
-s
Displays the server-side information.
-z
Specifies that the statistics should be set to zero.
If no options are supplied, the -cnrs options are used.
Gathering server-side statistics can be important for debugging problems when new software or
new hardware is added to the computing environment. Running this command a minimum of
once a week, and storing the numbers, provides a good history of previous performance.
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EXAMPLE 10
Displaying NFS Server Statistics
$ nfsstat -s
Server rpc:
Connection oriented:
calls
badcalls
719949194 0
Connectionless:
calls
badcalls
73753609 0
nullrecv
0
badlen
0
xdrcall
0
dupchecks dupreqs
58478624 33
nullrecv
0
badlen
0
xdrcall
0
dupchecks dupreqs
987278
7254
Server NFSv2:
calls
badcalls
25733
0
referrals referlinks
0
0
Server NFSv3:
calls
badcalls
132880073 0
referrals referlinks
0
0
Server NFSv4:
calls
badcalls referrals referlinks
488884996 4
0
0
Version 2: (746607 calls)
null
getattr
setattr
root
lookup
883 0%
60 0%
45 0%
0 0%
177446 23%
wrcache
write
create
remove
rename
0 0%
1105 0%
47 0%
59 0%
28 0%
mkdir
rmdir
readdir
statfs
26 0%
0 0%
27926 3% 108 0%
Version 3: (728863853 calls)
null
getattr
setattr
lookup
1365467 0%
496667075 68% 8864191 1%
66510206 9%
readlink
read
write
create
414705 0%
80123469 10% 18740690 2% 4135195 0%
symlink
mknod
remove
rmdir
101415 0%
9605 0%
6533288 0%
111810 0%
link
readdir
readdirplus fsstat
2572965 0%
519346 0%
2726631 0%
13320640 1%
pathconf
commit
13181 0%
6248828 0%
Version 4: (54871870 calls)
null
compound
266963 0%
54604907 99%
Version 4: (167573814 operations)
reserved
access
close
0 0%
2663957 1%
2692328 1%
create
delegpurge
delegreturn
readlink
1489 0%
link
10 0%
read
537366 71%
symlink
9 0%
access
19131659 2%
mkdir
327059 0%
rename
366267 0%
fsinfo
60161 0%
commit
1166001 0%
getattr
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167423 0%
getfh
11534581 6%
locku
230430 0%
open
2835459 1%
putfh
52606920 31%
readdir
606651 0%
renew
2330092 1%
setattr
453126 0%
write
3247770 1%
0 0%
link
113212 0%
lookup
11059722 6%
openattr
4138 0%
putpubfh
0 0%
readlink
38043 0%
restorefh
8711358 5%
setclientid
16349 0%
release_lockowner
0 0%
Server nfs_acl:
Version 2: (694979 calls)
null
getacl
setacl
0 0%
42358 6%
0 0%
Version 3: (2465011 calls)
null
getacl
setacl
0 0%
1293312 52% 1131 0%
1802019 1%
lock
207723 0%
lookupp
423514 0%
open_confirm
18959 0%
putrootfh
35776 0%
remove
560797 0%
savefh
11639329 6%
setclientid_confirm
16356 0%
illegal
0 0%
getattr
access
584553 84% 68068 9%
26405254 15%
lockt
265 0%
nverify
21386866 12%
open_downgrade
3106 0%
read
4325432 2%
rename
248990 0%
secinfo
19384 0%
verify
2484 0%
getxattrdir
0 0%
getxattrdir
1170568 47%
The example shows how to display the statistics for RPC and NFS activities. In both sets of
statistics, knowing the average number of badcalls or calls and the number of calls per week
can help identify a problem. The badcalls value reports the number of bad messages from a
client. This value can indicate network hardware problems.
Some of the connections generate write activity on the disks. A sudden increase in these
statistics could indicate trouble and should be investigated. For NFS Version 2 statistics, the
connections to note are setattr, write, create, remove, rename, link, symlink, mkdir, and
rmdir. For NFS Version 3 and NFS Version 4 statistics, the value to watch is commit. If the
commit level is high in one NFS server compared to another almost identical server, check that
the NFS clients have enough memory. The number of commit operations on the server grows
when clients do not have available resources.
pstack Command
The pstack command displays a stack trace for each process. The pstack command must be
run by the owner of the process or by root. You can use the pstack command to determine
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where a process is hung. The only option that is allowed with this command is the process ID of
the process that you want to check. For more information about the pstack command, see the
proc(1) man page.
EXAMPLE 11
Displaying Stack Trace for NFS Process
$ /usr/bin/pgrep nfsd
243
$ /usr/bin/pstack 243
243:
/usr/lib/nfs/nfsd -a 16
ef675c04 poll
(24d50, 2, ffffffff)
000115dc ???????? (24000, 132c4, 276d8, 1329c, 276d8, 0)
00011390 main
(3, efffff14, 0, 0, ffffffff, 400) + 3c8
00010fb0 _start (0, 0, 0, 0, 0, 0) + 5c
The example shows that the process is waiting for a new connection request, which is a
normal response. If the stack shows that the process is still in poll after a request is made, the
process might be hung. For more information about fixing a hung process, see “How to Restart
NFS Service” on page 145. For more information about troubleshooting NFS, see “NFS
Troubleshooting Procedures” on page 140.
rpcinfo Command
The rpcinfo command generates information about the RPC service that is running on a
system. Use the following command syntaxes to display information about the RPC service:
rpcinfo [-m|-s] [hostname]
rpcinfo [-T transport] [hostname] [progname]
rpcinfo [-t|-u] [hostname] [progname]
-m
Displays a table of statistics of the rpcbind operations
-s
Displays a concise list of all registered RPC programs
-T transport
Displays information about services that use specific transports or
protocols
-t
Probes the RPC programs that use TCP
-u
Probes the RPC programs that use UDP
transport
Specifies the transport or protocol for the services
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hostname
Specifies the host name of the server
progname
Specifies the name of the RPC program
For more information about the available options, see the rpcinfo(1M) man page.
If no value is given for hostname, the local host name is used. You can substitute the RPC
program number for progname, but the name is more commonly used. You can use the -p
option in place of the -s option on those systems that do not run the NFS Version 3 software.
The data that is generated by this command can include the following:
■
■
■
■
■
RPC program number
Version number for a specific program
Transport protocol in use
Name of the RPC service
Owner of the RPC service
EXAMPLE 12
Displaying RPC Service Information
$ rpcinfo -s bee |sort -n
program version(s) netid(s)
100000 2,3,4
udp6,tcp6,udp,tcp,ticlts,ticotsord,ticots
100001 4,3,2
udp6,udp,ticlts
100003 4,3,2
tcp,udp,tcp6,udp6
100005 3,2,1
ticots,ticotsord,tcp,tcp6,ticlts,udp,udp6
100007 1,2,3
ticots,ticotsord,ticlts,tcp,udp,tcp6,udp6
100011 1
udp6,udp,ticlts
100021 4,3,2,1 tcp,udp,tcp6,udp6
100024 1
ticots,ticotsord,ticlts,tcp,udp,tcp6,udp6
100068 5,4,3,2 ticlts
100083 1
ticotsord
100133 1
ticots,ticotsord,ticlts,tcp,udp,tcp6,udp6
100134 1
ticotsord
100155 1
ticotsord
100169 1
ticots,ticotsord,ticlts
100227 3,2
tcp,udp,tcp6,udp6
100234 1
ticotsord
390113 1
tcp
390435 1
tcp
390436 1
tcp
1073741824 1
tcp,tcp6
service
portmapper
rstatd
nfs
mountd
ypbind
rquotad
nlockmgr
status
smserverd
nfs_acl
-
owner
superuser
superuser
1
superuser
1
superuser
1
superuser
superuser
superuser
superuser
superuser
superuser
superuser
1
superuser
superuser
superuser
superuser
1
The example shows information about the RPC services that are running on a server. The output
that is generated by the command is filtered by the sort command by program number to make
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the information more readable. Several lines that list RPC services have been deleted from the
example.
You can gather information about a particular RPC service by selecting a particular transport on
a server. The following example checks the mountd service that is running over TCP.
$ rpcinfo -t bee mountd
program 100005 Version 1 ready and waiting
program 100005 Version 2 ready and waiting
program 100005 Version 3 ready and waiting
The following example checks the NFS service that is running over UDP.
$ rpcinfo -u bee nfs
program 100003 Version 2 ready and waiting
program 100003 Version 3 ready and waiting
snoop Command
The snoop command is used to monitor packets on the network. The snoop command must
be run as the root user. The use of this command is a good way to ensure that the network
hardware is functioning on both the NFS client and the NFS server.
Use the following command syntax to monitor packets on the network:
snoop [-d device] [-o filename] [host hostname]
-d device
Specifies the local network interface
-o filename
Stores all the captured packets into the named file
hostname
Displays packets going to and from a specific host only
The -d device option is useful on servers that have multiple network interfaces. You can use
many expressions other than setting the host. A combination of command expressions with
grep can often generate data that is specific enough to be useful. For more information about
the available options, see the snoop(1M) man page.
When troubleshooting, make sure that packets are going to and from the proper host. Also, look
for error messages. Saving the packets to a file can simplify the review of the data.
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NFS Troubleshooting Procedures
truss Command
You can use the truss command to check whether a process is hung. The truss command must
be run by the owner of the process or by root.
Use the following command syntax to check whether a process is hung:
truss [-t syscall] -p pid
-t syscall
Selects system calls to trace
-p pid
Indicates the PID of the process to be traced
syscall is a comma-separated list of system calls to be traced. Starting the list with an !
character excludes the listed system calls from the trace. For more information about the
available options, see the truss(1) man page.
EXAMPLE 13
Displaying Process Status
$ /usr/bin/truss -p 243
poll(0x00024D50, 2, -1)
(sleeping...)
The example shows that the process is waiting for another connection request, which is a
normal response. If the response does not change after a new connection request has been made,
the process could be hung.
For information about restarting the NFS service, see “How to Restart NFS
Service” on page 145. For information about troubleshooting a hung process, see “NFS
Troubleshooting Procedures” on page 140.
NFS Troubleshooting Procedures
To determine where the NFS service has failed, you need to follow several procedures to isolate
the failure. Check for the following:
■
■
■
Can the client reach the server?
Can the client contact the NFS service on the server?
Are the NFS services running on the server?
During this process, you might notice that other portions of the network are not functioning.
For example, the name service or the physical network hardware might not be functioning.
For information about naming services, see Working With Oracle Solaris 11.3 Directory and
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How to Check Connectivity on an NFS Client
Naming Services: DNS and NIS. Also, during the process you might see that the problem is not
at the client end, for example, if you receive a problem from every subnet in your work area. In
this situation, assume that the problem is the server or the network hardware near the server and
start the debugging process at the server, not at the client.
How to Check Connectivity on an NFS Client
1.
On the client, check that the NFS server is reachable.
$ /usr/sbin/ping bee
bee is alive
If the command reports that the server is alive, remotely check the NFS server. For
information about remotely checking the NFS server, see “How to Check the NFS Server
Remotely” on page 142.
2.
If the server is not reachable from the client, ensure that the local name service
is running on the client.
For example:
3.
■
If you are using the NIS name service, verify that the ypbind daemon is running. For more
information, see “ypbind Not Running on NIS Client” in Working With Oracle Solaris 11.3
Directory and Naming Services: DNS and NIS.
■
If you are using the LDAP name service, verify that the ldap_cachemgr daemon is running.
For more information, see “Monitoring LDAP Client Status” in Working With Oracle
Solaris 11.3 Directory and Naming Services: LDAP.
If the name service is running, ensure that the client has received the correct
host information.
$ /usr/bin/getent hosts system
For example:
$ /usr/bin/getent hosts bee
192.0.2.0 bee.eng.example.com
4.
If the host information is correct but the server is not reachable from the client,
run the ping command from another client.
If the command run from a second client fails, check whether the NFS service is
enabled on the server. For more information, see “How to Verify the NFS Service on the
Server” on page 143.
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How to Check the NFS Server Remotely
5.
If the server is reachable from the second client, use ping to check connectivity
of the first client to other systems on the local network.
If the ping command fails, check the networking software configuration on the client, for
example, the/etc/netmasks file and the property information associated with the svc:/
system/name-service/switch service.
6.
(Optional) Check the output of the rpcinfo command.
If the rpcinfo command does not display program 100003 Version 4 ready and waiting,
then NFS Version 4 is not enabled on the server. For information about enabling NFS Version 4,
see Table 4, “Setting Up the NFS Service,” on page 81.
7.
If the software is correct, check the networking hardware.
Try to move the client to a different physical network connection.
How to Check the NFS Server Remotely
Note that support for both the UDP and the MOUNT protocols is not necessary if you are using
an NFS Version 4 server.
1.
Check that the NFS daemons have started on the NFS server.
$ rpcinfo -s server-name|egrep 'nfs|mountd'
For example:
$ rpcinfo -s bee|egrep 'nfs|mountd'
100003 3,2
tcp,udp,tcp6,upd6
nfs
superuser
100005 3,2,1 ticots,ticotsord,tcp,tcp6,ticlts,udp,upd6 mountd superuser
If the daemons have not been started, restart the NFS service. For more information, see “How
to Restart NFS Service” on page 145.
2.
On the client, test the UDP NFS connections from the server.
$ /usr/bin/rpcinfo -u bee nfs
program 100003 Version 2 ready and waiting
program 100003 Version 3 ready and waiting
Note - NFS Version 4 does not support UDP.
If the server is running, the rpcinfo command lists program and version numbers that are
associated with the UDP protocol. You can use the -t option with the rpcinfo command to
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How to Verify the NFS Service on the Server
check the TCP connection. If the rpcinfo command fails, check whether the NFS service
is enabled on the server. For more information, see “How to Verify the NFS Service on the
Server” on page 143.
3.
Check that the server's mountd daemon is responding.
$ /usr/bin/rpcinfo -u bee mountd
program 100005 Version 1 ready and waiting
program 100005 Version 2 ready and waiting
program 100005 Version 3 ready and waiting
If the server is running, the rpcinfo command lists program and version numbers that are
associated with the UDP protocol. Using the -t option tests the TCP connection. Check whether
the nfsd and mountd daemon are running.
4.
Check whether the local autofs service is used by the client by changing to a
/net or /home mount point that works properly.
$ cd /net/eng
If this command fails, then as the root user on the client, restart the autofs service.
$ svcadm restart system/filesystem/autofs
5.
Verify that the file system is shared as expected on the server.
$ /usr/sbin/showmount -e bee
/usr/src
eng
/export/share/man
(everyone)
Check the entry on the server and the local mount entry for errors. Also, check the namespace.
In this example, if the first client is not in the eng netgroup, that client cannot mount the /usr/
src file system.
Check all entries that include mounting information in all the local files. The list includes the
/etc/vfstab file and all the /etc/auto_* files.
How to Verify the NFS Service on the Server
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Check that the server can reach the client.
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143
How to Verify the NFS Service on the Server
$ ping lilac
lilac is alive
3.
If the client is not reachable from the server, ensure that the local name service
is running on the client.
4.
If the name service is running, check the networking software configuration
on the server. For example, check /etc/netmasks and the property information
associated with the svc:/system/name-service/switch service.
5.
Check whether the rpcbind daemon is running on the server.
$ /usr/bin/rpcinfo -u localhost rpcbind
program 100000 Version 1 ready and waiting
program 100000 Version 2 ready and waiting
program 100000 Version 3 ready and waiting
If the server is running, the rpcinfo command lists program and version numbers that are
associated with the UDP protocol.
6.
Check whether the nfsd daemon is running on the server.
$ rpcinfo -u localhost
program 100003 Version
program 100003 Version
$ ps -ef | grep nfsd
root 101328
0 0
root 101327
1 0
root 263149 131084 0
nfs
2 ready and waiting
3 ready and waiting
Jul 12 ?
Jul 12 ?
13:59:19 pts/17
303:25 nfsd_kproc
2:54 /usr/lib/nfs/nfsd
0:00 grep nfsd
Note - NFS Version 4 does not support UDP.
If the server is running, the rpcinfo command lists program and version numbers that are
associated with the UDP protocol. Also, use the -t option with rpcinfo to check the TCP
connection. If these commands fail, restart the NFS service. For more information, see “How to
Restart NFS Service” on page 145.
7.
Check whether the mountd daemon is running on the server.
$ /usr/bin/rpcinfo -t localhost mountd
program 100005 Version 1 ready and waiting
program 100005 Version 2 ready and waiting
program 100005 Version 3 ready and waiting
$ ps -ef | grep mountd
root
145
1 0 Apr 07 ?
21:57 /usr/lib/autofs/automountd
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How to Restart NFS Service
root
root
234
1 0 Apr 07 ?
0:04 /usr/lib/nfs/mountd
3084 2462 1 09:30:20 pts/3 0:00 grep mountd
If the server is running, the rpcinfo command lists program and version numbers that are
associated with the UDP protocol. Also, use the -t option with rpcinfo to check the TCP
connection. If these commands fail, restart the NFS service. For more information, see “How to
Restart NFS Service” on page 145.
How to Restart NFS Service
1.
Become an administrator.
For more information, see “Using Your Assigned Administrative Rights” in Securing Users and
Processes in Oracle Solaris 11.3.
2.
Restart the NFS service on the server.
$ svcadm restart network/nfs/server
Identifying the Host Providing the NFS Service
Use the nfsstat command with the -m option to display the current NFS information. The name
of the current server is printed after “currserver=”.
For example:
$ nfsstat -m
/usr/local from bee,wasp:/export/share/local
Flags: vers=3,proto=tcp,sec=sys,hard,intr,llock,link,synlink,
acl,rsize=32768,wsize=32678,retrans=5
Failover: noresponse=0, failover=0, remap=0, currserver=bee
How to Verify Options Used With the mount
Command
No warning is issued for invalid options that are supplied with the mount command. This
procedure helps determine whether the options that were supplied either on the command line
or through the /etc/vfstab file were valid.
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Troubleshooting Autofs
For the example in this procedure, assume that the following command has been run:
$ mount -F nfs -o ro,vers=2 bee:/export/share/local /mnt
1.
Verify the options.
$ nfsstat -m
/mnt from bee:/export/share/local
Flags: vers=2,proto=tcp,sec=sys,hard,intr,dynamic,acl,rsize=8192,wsize=8192,
retrans=5
The file system from the bee server has been mounted with the protocol version set to 2. The
nfsstat command does not display information about all of the options. However, using the
nfsstat command is the most accurate way to verify the options.
2.
Check the entry in the /etc/mnttab file.
The mount command does not allow invalid options to be added to the mount table. Therefore,
verify that the options that are listed in the file match the options that are listed on the command
line. In this way, you can check the options that are not reported by the nfsstat command.
$ grep bee /etc/mnttab
bee:/export/share/local /mnt nfs ro,vers=2,dev=2b0005e 859934818
Troubleshooting Autofs
Occasionally, you might encounter problems with autofs. This section presents a list of the
error messages that autofs generates. The list is divided into two parts:
■
■
Error messages that are generated by the verbose (-v) option of automount
Error messages that might appear at any time
Each error message is followed by a description and probable cause of the message.
When troubleshooting, start the autofs programs with the verbose (-v) option.
Error Messages Generated by automount -v
bad key key in direct map mapname
Description: While
prefixed /.
146
scanning a direct map, autofs has found an entry key without a
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Troubleshooting Autofs
Solution: Keys
in direct maps must be full path names.
bad key key in indirect map mapname
Description: While
scanning an indirect map, autofs has found an entry key that contains a
/.
Solution: Indirect
map keys must be simple names, not path names.
can't mount server:pathname: reason
Description: The
mount daemon on the server refuses to provide a file handle for
server:pathname.
Solution: Check
the export table on the server.
couldn't create mount point mountpoint: reason
Description: Autofs
was unable to create a mount point that was required for a mount. This
problem most frequently occurs when you attempt to hierarchically mount all of a server's
exported file systems.
Solution: A
required mount point can exist only in a file system that cannot be mounted,
which means the file system cannot be exported. The mount point cannot be created because
the exported parent file system is exported read-only.
leading space in map entry entry text in mapname
Description: Autofs
has discovered an entry in an automount map that contains leading
spaces. This problem is usually an indication of an improperly continued map entry. For
example:
fake
/blat
frobz:/usr/frotz
Solution: In
this example, the warning is generated when autofs encounters the second line
because the first line should be terminated with a backslash (\).
mapname: Not found
Description: The
option is used.
required map cannot be located. This message is produced only when the -v
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Troubleshooting Autofs
Solution: Check
the spelling and path name of the map name.
remount server:pathname on mountpoint: server not responding
Description: Autofs
has failed to remount a file system that it previously unmounted.
Solution: Contact
My Oracle Support for assistance. This error message is extremely rare and
has no straightforward solution.
WARNING: mountpoint already mounted on
Description: Autofs
is attempting to mount over an existing mount point. This message
means that an internal error occurred in autofs (an anomaly).
Solution: Contact
My Oracle Support for assistance. This error message is extremely rare and
has no straightforward solution.
Miscellaneous Error Messages
dir mountpoint must start with '/'
Solution: The
automounter mount point must be given as a full path name. Check the spelling
and path name of the mount point.
hierarchical mountpoint: pathname1 and pathname2
Solution: Autofs
does not allow its mount points to have a hierarchical relationship. An
autofs mount point must not be contained within another automounted file system.
host server not responding
Description: Autofs
Solution: Check
attempted to contact server, but received no response.
the NFS server status.
hostname: exports: rpc-err
Description: An
error occurred while getting the export list from hostname. This message
indicates a server or network problem.
Solution: Check
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map mapname, key key: bad
Description: The
map entry is malformed and autofs cannot interpret the entry.
Solution: Recheck
the entry. Perhaps the entry has characters that need to be escaped.
mapname: nis-err
Description: An
error occurred when looking up an entry in a NIS map. This message can
indicate NIS problems.
Solution: Check
the NIS server status.
mount of server:pathname on mountpoint:reason
Description: Autofs
failed to do a mount. This occurrence can indicate a server or network
problem. The reason string defines the problem.
Solution: Contact
My Oracle Support for assistance. This error message is extremely rare and
has no straightforward solution.
mountpoint: Not a directory
Description: Autofs
Solution: Check
cannot mount itself on mountpoint because it is not a directory.
the spelling and path name of the mount point.
nfscast: cannot send packet: reason
Description: Autofs
cannot send a query packet to a server in a list of replicated file system
locations. The reason string defines the problem.
Solution: Contact
My Oracle Support for assistance. This error message is extremely rare and
has no straightforward solution.
nfscast: cannot receive reply: reason
Description: Autofs
cannot receive replies from any of the servers in a list of replicated file
system locations. The reason string defines the problem.
Solution: Contact
My Oracle Support for assistance. This error message is extremely rare and
has no straightforward solution.
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nfscast: select: reason
Description: This
error message indicates problem in attempting to check servers for a
replicated file system. This message can indicate a network problem. The reason string
defines the problem.
Solution: Contact
My Oracle Support for assistance. This error message is extremely rare and
has no straightforward solution.
pathconf: no info for server:pathname
Description: Autofs
Solution: For
failed to get pathconf information for the path name.
information about configurable path names, see the fpathconf(2) man page.
pathconf: server: server not responding
Description: Autofs
is unable to contact the mount daemon on server that provides the
information to pathconf().
Solution: Avoid
using the POSIX mount option with this server.
Other Errors With Autofs
If the /etc/auto* files have the execute bit set, the automounter tries to execute the maps,
which creates messages such as the following:
/etc/auto_home: +auto_home: not found
In this situation, the auto_home file has incorrect permissions. Each entry in the file generates
an error message that is similar to this message. Type the following command to reset the
permissions to the file:
$ chmod 644 /etc/auto_home
NFS Error Messages
This section lists NFS error messages followed by a description of the conditions that can create
the error and possible solutions.
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Bad argument specified with index option - must be a file
Solution: You
names.
must include a file name with the index option. You cannot use directory
Cannot establish NFS service over /dev/tcp: transport setup problem
Description: This
message is often generated when the services information in the namespace
has not been updated. The message can also be reported for UDP.
Solution: To
fix this problem, you must update the services data in the namespace.
For NIS and /etc/services, the entries must be as follows:
nfsd
nfsd
2049/tcp
2049/udp
nfs
nfs
# NFS server daemon
# NFS server daemon
Could not start daemon: error
Description: This
message is displayed if the daemon terminates abnormally or if a system
call error occurs. The error string defines the problem.
Solution: Contact
My Oracle Support for assistance. This error message is rare and has no
straightforward solution.
Could not use public filehandle in request to server
Description: This
message is displayed if the public option is specified but the NFS server
does not support the public file handle. In this situation, the mount fails.
Solution: Either
try the mount request without using the public file handle or reconfigure the
NFS server to support the public file handle.
daemon running already with pid pid
Description: The
Solution: If
version.
daemon is already running.
you want to run a new process, terminate the current version and start a new
error locking lock-file
Description: This
message is displayed when the lock-file that is associated with a daemon
cannot be locked properly.
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NFS Error Messages
Solution: Contact
My Oracle Support for assistance. This error message is rare and has no
straightforward solution.
error checking lock-file: error
Description: This
message is displayed when the lock-file that is associated with a daemon
cannot be opened properly.
Solution: Contact
My Oracle Support for assistance. This error message is rare and has no
straightforward solution.
NOTICE: NFS3: failing over from host1 to host2
Description: This
advisory only.
Solution: No
message is displayed on the console when a failover occurs. The message is
action is required.
filename: File too large
Description: An
NFS Version 2 client is trying to access a file that is over 2 Gbytes.
Solution: Avoid
using NFS Version 2. Mount the file system with NFS Version 3 or NFS
Version 4. Also, see the description of the nolargefiles option in the mount(1M) man page.
mount: ... server not responding:RPC_PMAP_FAILURE - RPC_TIMED_OUT
Description: The
server that is sharing the file system you are trying to mount is down,
unreachable, or at the wrong run level, or the rpcbind process is dead or hung.
Solution: Wait
for the server to reboot. If the server is hung, reboot the server.
mount: ... server not responding: RPC_PROG_NOT_REGISTERED
Description: The
mount request is registered with the rpcbind process but the NFS mount
daemon mountd is not registered.
Solution: Wait
for the server to reboot. If the server is hung, reboot the server.
mount: ... No such file or directory
Description: Either
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Solution: Check
the spelling of the directory names. Run ls on both directories.
mount: ...: Permission denied
Description: Your
system name might not be in the list of clients or the netgroup that is
allowed access to the file system you tried to mount.
Solution: Use
the showmount -e command to verify the access list.
NFS file temporarily unavailable on the server, retrying ...
Description: An
NFS Version 4 server can delegate the management of a file to a client. This
message indicates that the server is recalling a delegation for another client that conflicts
with a request from your client.
Solution: The
recall must occur before the server can process your client's request. For more
information about delegation, see “Delegation in NFS Version 4” on page 35.
NFS fsstat failed for server hostname: RPC: Authentication error
Description: This
error can be caused by many situations. One of the most difficult situations
to debug is when this problem occurs because a user is in too many groups. Currently, a user
can be in no more than 16 groups if the user is accessing files through NFS mounts.
Solution: An
alternative does exist for users who need to be in more than 16 groups. You can
use access control lists (ACLs) to provide the needed access privileges.
nfs mount: NFS can't support “nolargefiles”
Description: An
NFS client has attempted to mount a file system from an NFS server by
using the -nolargefiles option.
Solution: This
option is not supported for NFS file system types.
nfs mount: NFS V2 can't support “largefiles”
Description: The
Solution: You
NFS Version 2 protocol cannot handle large files.
must use NFS Version 3 or NFS Version 4 if access to large files is required.
NFS server hostname not responding still trying
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Description: If
programs hang while doing file-related work, your NFS server might have
failed. This message indicates that NFS server hostname is down or that a problem has
occurred with the server or the network.
Solution: If
NFS failover is being used, hostname is a list of servers. Start troubleshooting
with “How to Check Connectivity on an NFS Client” on page 141.
NFS server recovering
Description: During
part of the NFS Version 4 server reboot, some operations were not
permitted. This message indicates that the client is waiting for the server to permit this
operation to proceed.
Solution: No
action is required. Wait for the server to permit the operation.
Permission denied
Description: This
message is displayed by the ls -l, getfacl, and setfacl commands for the
following reasons:
■
■
■
If the user or group that exists in an access control list (ACL) entry on an NFS Version 4
server cannot be mapped to a valid user or group on an NFS Version 4 client, the user is
not allowed to read the ACL on the client.
If the user or group that exists in an ACL entry that is being set on an NFS Version 4
client cannot be mapped to a valid user or group on an NFS Version 4 server, the user is
not allowed to write or modify an ACL on the client.
If an NFS Version 4 client and server have mismatched nfsmapid_domain values, ID
mapping fails.
For more information about ACL entries for NFS, see “ACLs and nfsmapid in NFS Version
4” on page 37.
Solution: Do
the following:
■
Make sure that all user IDs and group IDs in the ACL entries exist on both the client and
server.
■
Make sure that the value for the nfsmapid_domain property is set correctly in the SMF
repository.
For information about the script used to determine whether any user or group cannot
be mapped on the server or client, see “Checking for Unmapped User IDs or Group
IDs” on page 38.
port number in nfs URL not the same as port number in port option
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Description: The
port number that is included in the NFS URL must match the port number
that is included with the -port option to mount. If the port numbers do not match, the mount
fails.
Solution: Either
change the command to make the port numbers identical or do not specify
the port number that is incorrect. Usually, you do not need to specify the port number with
both the NFS URL and the -port option.
replicas must have the same version
Description: For
NFS failover to function properly, the NFS servers that are replicas must
support the same version of the NFS protocol.
Solution: Do
not run multiple versions.
replicated mounts must be read-only
Description: NFS
failover does not work on file systems that are mounted read-write.
Mounting the file system read-write increases the likelihood that a file could change.
Solution: NFS
failover depends on the file systems being identical.
replicated mounts must not be soft
Description: Replicated
occurs.
mounts require that you wait for a timeout before NFS failover
Solution: The
soft option requires that the mount fail immediately when a timeout starts, so
you cannot include the -soft option with a replicated mount.
share_nfs: Cannot share more than one filesystem with 'public' option
Solution: Use
the share command to make sure that only one file system is selected to be
shared with the -public option. Only one public file handle can be established per server, so
only one file system per server can be shared with this option.
WARNING: No network locking on hostname:path: contact admin to install server change
Description: An
NFS client has unsuccessfully attempted to establish a connection with
the Network Lock Manager on an NFS server. Rather than fail the mount, this warning is
generated to warn you that locking does not work.
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Solution: Upgrade
manager support.
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♦ ♦ ♦
7
C H A P T E R
7
Accessing Network File Systems
This chapter includes a list of files and daemons that support the NFS service.
This chapter contains the following topics:
■
■
“NFS Files” on page 157
“NFS Daemons” on page 160
Note - If your system has zones enabled and you want to use this feature in a non-global zone,
see Introduction to Oracle Solaris Zones.
NFS Files
You need several files to support NFS activities on any system. Many of these files are in
ASCII format, but some of the files are data files. The following table lists NFS files and their
functions.
TABLE 7
NFS Files
File Name
Function
Man Page
/etc/default/fs
Specifies the default file system type for local file
systems. You can determine the file system types that are
supported on a client or server by checking the files in
/kernel/fs.
fs(4) man page.
/etc/default/nfslogd
Specifies configuration information for the NFS server
logging daemon, nfslogd.
nfslogd(1M) man page.
/etc/dfs/dfstab
Obsolete: Specifies the local resources to be shared.
dfstab(4) man page.
/etc/dfs/fstypes
Specifies the default file system types for remote file
systems. The first entry defines the NFS file system type
as the default.
fstypes(4) man page.
/etc/dfs/sharetab
Specifies the local and remote resources that are shared.
Do not edit this file.
sharetab(4) man page.
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File Name
Function
Man Page
/etc/mnttab
Specifies file systems that are currently mounted,
including automounted directories. Do not edit this file.
mnttab(4) man page.
/etc/netconfig
Specifies the transport protocols. Do not edit this file.
netconfig(4) man page.
/etc/nfs/nfslog.conf
Specifies general configuration information for NFS
server logging.
nfslog.conf(4) man page.
/etc/nfs/nfslogtab
Specifies information for log post processing by the
nfslogd daemon. Do not edit this file.
/etc/nfssec.conf
Specifies NFS security services.
nfssec.conf(4) man page.
/etc/rmtab
Specifies file systems that are remotely mounted by NFS
clients. Do not edit this file.
rmtab(4) man page.
/etc/vfstab
Defines file systems to be mounted locally.
vfstab(4) man page.
/etc/default/nfslogd File
This file defines some of the parameters that are used when using NFS server logging.
Note - NFS Version 4 does not support NFS server logging.
The following parameters can be defined:
CYCLE_FREQUENCY
Determines the number of hours that must pass before the log files are cycled. The default
value is 24 hours. Use this option to prevent the log files from growing too large.
IDLE_TIME
Sets the number of seconds nfslogd should sleep before checking for more information in
the buffer file. This parameter also determines how often the configuration file is checked.
This parameter, along with MIN_PROCESSING_SIZE, determines how often the buffer
file is processed. The default value is 300 seconds. Increasing this number can improve
performance by reducing the number of checks.
MAPPING_UPDATE_INTERVAL
Specifies the number of seconds between updates of the records in the file-handle-to-path
mapping tables. The default value is 86400 seconds or one day. This parameter helps keep
the file-handle-to-path mapping tables up to date without having to continually update the
tables.
MAX_LOGS_PRESERVE
Determines the number of log files to be saved. The default value is 10.
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MIN_PROCESSING_SIZE
Sets the minimum number of bytes that the buffer file must reach before processing and
writing to the log file. This parameter, along with IDLE_TIME, determines how often the
buffer file is processed. The default value is 524288 bytes. Increasing this number can
improve performance by reducing the number of times the buffer file is processed.
PRUNE_TIMEOUT
Selects the number of hours that must pass before a file-handle-to-path mapping record
times out and can be reduced. The default value is 168 hours or 7 days.
UMASK
Specifies the file mode creation mask for the log files that are created by nfslogd. The
default value is 0137.
/etc/nfs/nfslog.conf File
This file defines the path, file names, and type of logging to be used by nfslogd. Each
definition is associated with a tag. Starting NFS server logging requires that you identify the tag
for each file system. The global tag defines the default values.
Note - NFS Version 4 does not support NFS server logging.
You can use the following parameters with each tag as needed.
defaultdir=path
Specifies the default directory path for the logging files. Unless you specify differently, the
default directory is /var/nfs.
log=path/filename
Sets the path and file name for the log files. The default is /var/nfs/nfslog.
fhtable=path/filename
Selects the path and file name for the file-handle-to-path database files. The default is
/var/nfs/fhtable.
buffer=path/filename
Determines the path and file name for the buffer files. The default is /var/nfs/
nfslog_workbuffer.
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logformat=basic|extended
Selects the format to be used when creating user-readable log files. The basic format
produces a log file that is similar to some ftpd daemons. The extended format gives a more
detailed view.
If the path is not specified, the path that is defined by defaultdir is used. Also, you can
override defaultdir by using an absolute path.
To identify the files more easily, place the files in separate directories. The following example
shows the changes that are needed.
EXAMPLE 14
Sample NFS Server Logging Configuration File
$ cat /etc/nfs/nfslog.conf
#ident "@(#)nfslog.conf
1.5
#
.
.
# NFS server log configuration file.
#
99/02/21 SMI"
global defaultdir=/var/nfs \
log=nfslog fhtable=fhtable buffer=nfslog_workbuffer
publicftp log=logs/nfslog fhtable=fh/fhtables buffer=buffers/workbuffer
The example shows a file system that is shared with log=publicftp. A file system that is
shared with log=publicftp uses the following values:
■
The default directory is /var/nfs.
■
Log files are stored in /var/nfs/logs/nfslog*.
■
File-handle-to-path database tables are stored in /var/nfs/fh/fhtables.
■
Buffer files are stored in /var/nfs/buffers/workbuffer.
For information about enabling NFS server logging, refer to “How to Enable NFS Server
Logging” on page 73.
NFS Daemons
To support NFS activities, several daemons are started when a system goes into run level
or multiuser mode. The mountd and nfsd daemons are run on systems that are servers. The
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automatic startup of the server daemons depends on the existence of at least one NFS share. To
display the current list of NFS shares, run the share -F nfs command. To support NFS file
locking, the lockd and statd daemons are run on NFS clients and servers. However, unlike
previous versions of NFS, in NFS Version 4, the daemons lockd, statd, and nfslogd are not
used.
This section describes the following daemons.
■
■
■
■
■
■
■
■
■
“automountd Daemon” on page 161
“lockd Daemon” on page 162
“mountd Daemon” on page 163
“nfs4cbd Daemon” on page 164
“nfsd Daemon” on page 164
“nfslogd Daemon” on page 165
“nfsmapid Daemon” on page 165
“reparsed Daemon” on page 172
“statd Daemon” on page 172
automountd Daemon
The automountd daemon handles the mounting and unmounting requests from the autofs
service. The syntax of the command is as follows:
automountd [-Tnv] [-D name=value]
-T
Enables tracing.
-n
Disables browsing on all autofs nodes.
-v
Logs all status messages to the console.
-D name=value
Substitutes value for the automount map variable that is indicated by
name.
The default value for the automount map is /etc/auto_master. Use the -T option for
troubleshooting.
You can make the same specifications with the sharectl command that you would make on the
command line. However, unlike the command-line options, the SMF repository preserves your
specifications, through service restarts and system reboots, as well as system upgrades. You can
set the following parameters for the automountd daemon.
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automountd_verbose
Logs status messages to the console and is the equivalent of the -v argument for the
automountd daemon. The default value is FALSE.
nobrowse
Turns browsing on or off for all autofs mount points and is the equivalent of the -n
argument for automountd. The default value is FALSE.
trace
Expands each remote procedure call (RPC) and displays the expanded RPC on standard
output. This keyword is the equivalent of the -T argument for automountd. The default
value is 0. Values can range from 0 to 5.
environment
Permits you to assign different values to different environments. This keyword is the
equivalent of the -D argument for automountd. The environment parameter can be used
multiple times. However, you must use separate entries for each environment assignment.
lockd Daemon
The lockd daemon supports record-locking operations on NFS files. The lockd daemon
manages RPC connections between the client and the server for the Network Lock Manager
(NLM) protocol. The daemon is normally started without any options. You can use three
options with this command. You can set these options either from the command line or by
setting parameters using the sharectl command. For more information, see the lockd(1M)
man page.
Note - The LOCKD_GRACE_PERIOD keyword and the -g option have been deprecated. The
deprecated keyword is replaced with the new grace_period parameter. If both keywords are
set, the value for grace_period overrides the value for LOCKD_GRACE_PERIOD.
Like LOCKD_GRACE_PERIOD, the grace_period=graceperiod parameter sets the number of
seconds after a server reboot that the clients have to reclaim both NFS Version 3 locks, provided
by NLM, and NFS Version 4 locks.
The lockd_retransmit_timeout=timeout parameter selects the number of seconds to wait
before retransmitting a lock request to the remote server. This option affects the NFS client-side
service. The default value for timeout is 5 seconds. Decreasing the timeout value can improve
response time for NFS clients on a “noisy” network. However, this change can cause additional
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server load by increasing the frequency of lock requests. The same parameter can be used from
the command line by starting the daemon with the -t timeout option.
The lockd_servers=number parameter specifies the maximum number of concurrent lockd
requests. The default value is 1024.
The nthreads parameter specifies the maximum number of concurrent threads that the server
can handle. All NFS clients that use UDP share a single connection with the NFS server. Under
these conditions, you might have to increase the number of threads that are available for the
UDP connection. A minimum calculation would be to allow two threads for each UDP client.
However, this number is specific to the workload on the client, so two threads per client might
not be sufficient. The disadvantage to using more threads is that when the threads are used,
more memory is used on the NFS server. If the threads are never used, however, increasing
nthreads has no effect. The same parameter can be used from the command line by starting the
daemon with the nthreads option.
mountd Daemon
The mountd daemon handles file system mount requests from remote systems and provides
access control. The mountd daemon checks /etc/dfs/sharetab to determine which file
systems are available for remote mounting and which systems are allowed to do the remote
mounting. For more information, see the mountd(1M) man page.
-v
Runs the command in verbose mode. Every time an NFS server
determines the access that a client should be granted, a message is printed
on the console. The information that is generated can be useful when
trying to determine why a client cannot access a file system.
-r
Rejects all future mount requests from clients. This option does not affect
clients that already have a file system mounted.
In addition to the command-line options, several SMF parameters can be used to configure the
mountd daemon:
client_versmin
Sets the minimum version of the NFS protocol to be used by the NFS client. The default is
2. Other valid values include 3 or 4. Refer to “Setting Up the NFS Service” on page 81.
client_versmax
Sets the maximum version of the NFS protocol to be used by the NFS client. The default is
4. Other valid values include 2 or 3. Refer to “Setting Up the NFS Service” on page 81.
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nfs4cbd Daemon
The nfs4cbd daemon, which is for the exclusive use of the NFS Version 4 client, manages the
communication endpoints for the NFS Version 4 callback program. The daemon has no useraccessible interface. For more information, see the nfs4cbd(1M) man page.
nfsd Daemon
The nfsd daemon handles client file system requests. You can use several options with this
command. See the nfsd(1M) man page for a complete listing. These options can either be
used from the command line or by setting the appropriate SMF parameter with the sharectl
command.
listen_backlog=length Sets the length of the connection queue over connection-oriented
transports for NFS and TCP. The default value is 32 entries. The same
selection can be made from the command line by starting nfsd with the
-l option.
max_connections=#conn
Selects the maximum number of connections per connection-oriented
transport. The default value for #-conn is unlimited. The same parameter
can be used from the command line by starting the daemon with the -c #conn option.
servers=nservers
Selects the maximum number of concurrent requests that a server can
handle. The default value for nservers is 1024. The same selection can be
made from the command line by starting nfsd with the nservers option.
Unlike older versions of this daemon, nfsd does not spawn multiple copies to handle concurrent
requests. Checking the process table with ps only shows one copy of the daemon running.
In addition, the following SMF parameters can be used to configure the mountd daemon. These
parameters do not have command-line equivalents:
server_versmin
Sets the minimum version of the NFS protocol to be registered and offered by the
server. The default is 2. Other valid values include 3 or 4. Refer to “Setting Up the NFS
Service” on page 81.
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server_versmax
Sets the maximum version of the NFS protocol to be registered and offered by the
server. The default is 4. Other valid values include 2 or 3. Refer to “Setting Up the NFS
Service” on page 81.
server_delegation
Controls whether the NFS Version 4 delegation feature is enabled for the server. If this
feature is enabled, the server attempts to provide delegations to the NFS Version 4 client.
By default, server delegation is enabled. To disable server delegation, see “How to
Select Different Versions of NFS on a Server” on page 82. For more information, refer to
“Delegation in NFS Version 4” on page 35.
nfslogd Daemon
Note - NFS Version 4 does not use this daemon.
The nfslogd daemon provides operational logging. NFS operations that are logged against
a server are based on the configuration options that are defined in /etc/default/nfslogd.
When NFS server logging is enabled, records of all RPC operations on a selected file system
are written to a buffer file by the kernel. Then nfslogd postprocesses these requests. The name
service switch is used to help map UIDs to logins and IP addresses to host names. The number
is recorded if no match can be found through the identified name services.
Mapping of file handles to path names is also handled by nfslogd. The daemon tracks these
mappings in a file-handle-to-path mapping table. One mapping table exists for each tag that is
identified in /etc/nfs/nfslogd. After post-processing, the records are written to ASCII log
files.
nfsmapid Daemon
Version 4 of the NFS protocol (RFC3530) changed the way user or group identifiers (UID or
GID) are exchanged between the client and server. The protocol requires that a file's owner and
group attributes be exchanged between an NFS Version 4 client and an NFS Version 4 server as
strings in the form at user@nfsv4-domain or group@nfsv4-domain, respectively.
For example, user known_user has a UID 123456 on an NFS Version 4 client whose fully
qualified hostname is system.example.com. For the client to make requests to the NFS Version
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4 server, the client must map the UID 123456 to known_user@example.com and then send
this attribute to the NFS Version 4 server. After the server receives known_user@example.com
from the client, the server maps the string to the local UID 123456, which is understood by the
underlying file system. This functionality assumes that every UID and GID in the network is
unique and that the NFS Version 4 domains on the client match the NFS Version 4 domains on
the server.
The NFS Version 4 client and server are both capable of performing integer-to-string and stringto-integer conversions. For example, in response to a GETATTR operation, the NFS Version 4
server maps UIDs and GIDs obtained from the underlying file system into their respective
string representation and sends this information to the client. Alternately, the client must
also map UIDs and GIDs into string representations. For example, in response to the chown
command, the client maps the new UID or GID to a string representation before sending a
SETATTR operation to the server.
Note, however, that the client and server respond differently to unrecognized strings:
■
■
■
■
If the user does not exist on the server, even within the same NFS Version 4 domain
configuration, the server rejects the remote procedure call (RPC) and returns an error
message to the client. This situation limits the operations that can be performed by the
remote user.
If the user exists on both the client and server but they have mismatched domains, the server
rejects the attribute modifying operations (such as SETATTR) that require the server to map
the inbound user string to an integer value that the underlying file system can understand.
For NFS Version 4 clients and servers to function properly, their NFS Version 4 domains,
the portion of the string after the @ sign, should match.
If the NFS Version 4 client does not recognize a user or group name from the server,
the client is unable to map the string to its unique ID, an integer value. Under such
circumstances, the client maps the inbound user or group string to the nobody user. This
mapping to nobody creates varied problems for different applications. With NFS Version 4,
operations that modify file attributes will fail.
If the server does not recognize the given user or group name, even if the NFS Version 4
domains match, the server is unable to map the user or group name to its unique ID, an
integer value. Under such circumstances, the server maps the inbound user or group name to
the nobody user. To prevent such occurrences, administrators should avoid making special
accounts that exist only on the NFS Version 4 client.
You can change the domain name for the clients and servers using the sharectl command with
the nfsmapid_domain option. This option sets a common domain for clients and servers. It
overrides the default behavior of using the local DNS domain name. For task information, refer
to “Setting Up the NFS Service” on page 81.
166
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
NFS Daemons
Configuration Files and the nfsmapid Daemon
The nfsmapid daemon uses the SMF configuration information found in svc:system/nameservice/switch and in svc:/network/dns/client as follows:
■
■
nfsmapid uses standard C library functions to request password and group information from
back-end name services. These name services are controlled by the settings in the svc:
system/name-service/switch SMF service. Any changes to the service properties affect
nfsmapid operations. For more information about the svc:system/name-service/switch
SMF service, see the nsswitch.conf(4) man page.
To ensure that NFS Version 4 clients are capable of mounting file systems from different
domains, nfsmapid relies on the configuration of the DNS TXT resource record (RR),
_nfsv4idmapdomain. For more information about configuring the _nfsv4idmapdomain
resource record, see “nfsmapid and DNS TXT Records” on page 168. Also, note the
following:
■
The DNS TXT RR should be explicitly configured on the DNS server with the desired
domain information.
■
The svc:system/name-service/switch SMF service should be configured to enable
the resolver to find the DNS server and search the TXT records for client and server
NFS Version 4 domains.
For more information, see the following:
■
“Precedence Rules” on page 167
“Configuring the NFS Version 4 Default Domain” on page 170
■
The resolv.conf(4) man page
■
Precedence Rules
For nfsmapid to work properly, NFS Version 4 clients and servers must have the same domain.
To ensure matching NFS Version 4 domains, nfsmapid follows these strict precedence rules:
1. The daemon first checks the SMF repository for a value that has been assigned to the
nfsmapid_domain parameter. If a value is found, the assigned value takes precedence over
any other settings. The assigned value is appended to the outbound attribute strings and is
compared against inbound attribute strings. For procedural information, see “Setting Up the
NFS Service” on page 81.
Chapter 7 • Accessing Network File Systems
167
NFS Daemons
Note - The use of the NFSMAPID_DOMAIN setting is not scalable and is not recommended for
large deployments.
2. If no value has been assigned to nfsmapid_domain, then the daemon checks for a domain
name from a DNS TXT RR. nfsmapid relies on directives in the /etc/resolv.conf file
that are used by the set of routines in the resolver. The resolver searches through the
configured DNS servers for the _nfsv4idmapdomain TXT RR. Note that the use of DNS
TXT records is more scalable. For this reason, continued use of TXT records is much
preferred over setting the parameter in the SMF repository.
3. If no DNS TXT record is configured to provide a domain name, then the nfsmapid daemon
uses the value specified by the domain or search directive in the /etc/resolv.conf file,
with the directive specified last taking precedence.
In the following example, both the domain and search directives are used. The nfsmapid
daemon uses the first domain listed after the search directive, which is example.com.
domain company.example.com
search example.com corp.example.com
4. If the /etc/resolv.conf file does not exist, nfsmapid obtains the NFS Version 4 domain
name by following the behavior of the domainname command. Specifically, if the /etc/
defaultdomain file exists, nfsmapid uses the contents of that file for the NFS Version 4
domain. If the /etc/defaultdomain file does not exist, nfsmapid uses the domain name
that is provided by the network's configured naming service. For more information, see the
domainname(1M) man page.
nfsmapid and DNS TXT Records
The ubiquitous nature of DNS provides an efficient storage and distribution mechanism for
the NFS Version 4 domain name. Additionally, because of the inherent scalability of DNS, the
use of DNS TXT resource records is the preferred method for configuring the NFS Version 4
domain name for large deployments. You should configure the _nfsv4idmapdomain TXT record
on enterprise-level DNS servers. Such configurations ensure that any NFS Version 4 client or
server can find its NFS Version 4 domain by traversing the DNS tree.
The following example shows a preferred entry for enabling the DNS server to provide the NFS
Version 4 domain name:
_nfsv4idmapdomain IN TXT
168
"corp.example"
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
NFS Daemons
In this example, the domain name to configure is the value that is enclosed in double quotes.
Note that no ttl field is specified and that no domain is appended to _nfsv4idmapdomain,
which is the value in the owner field. This configuration enables the TXT record to use the
zone's ${ORIGIN} entry from the Start-Of-Authority (SOA) record. For example, at different
levels of the domain namespace, the record could read as follows:
_nfsv4idmapdomain.subnet.example.com.
_nfsv4idmapdomain.example.com.
IN
IN
TXT
TXT
"corp.example"
"corp.example"
This configuration provides DNS clients with the added flexibility of using the resolv.conf
file to search up the DNS tree hierarchy. See the resolv.conf(4) man page. This capability
provides a higher probability of finding the TXT record. For even more flexibility, lower level
DNS subdomains can define their own DNS TXT resource records (RRs). This capability
enables lower level DNS subdomains to override the TXT record that is defined by the top level
DNS domain.
Note - The domain that is specified by the TXT record can be an arbitrary string that does not
necessarily match the DNS domain for clients and servers that use NFS Version 4. You have the
option of not sharing NFS Version 4 data with other DNS domains.
Checking for the NFS Version 4 Domain
Before assigning a value for your network's NFS Version 4 domain, check whether an NFS
Version 4 domain has already been configured for your network. The following examples
provide ways of identifying your network's NFS Version 4 domain.
■
To identify the NFS Version 4 domain from a DNS TXT RR, use either the nslookup or the
dig command:
The following example shows sample output for the nslookup command:
$ nslookup -q=txt _nfsv4idmapdomain
Server:
10.255.255.255
Address:
10.255.255.255#53
_nfsv4idmapdomain.company.example.com text = "example.com"
The following example shows sample output for the dig command:
$ dig +domain=company.example.com -t TXT _nfsv4idmapdomain
...
;; QUESTION SECTION:
Chapter 7 • Accessing Network File Systems
169
NFS Daemons
;_nfsv4idmapdomain.company.example.com. IN
TXT
;; ANSWER SECTION:
_nfsv4idmapdomain.company.example.com. 21600 IN TXT
"example.com"
;; AUTHORITY SECTION:
...
■
For information about setting up a DNS TXT RR, see “nfsmapid and DNS TXT
Records” on page 168.
If your network is not set up with a NFS Version 4 DNS TXT RR, use the following
command to identify your NFS Version 4 domain from the DNS domain name:
$ egrep domain /etc/resolv.conf
domain company.example.com
■
If the /etc/resolv.conf file is not configured to provide a DNS domain name for the
client, use the following command to identify the domain from the network's NFS Version 4
domain configuration:
$ cat /system/volatile/nfs4_domain
example.com
■
If you are using a different naming service, such as NIS, use the following command to
identify the domain for the naming service configured for your network:
$ domainname
it.company.example.com
For more information, see the following man pages:
■
nslookup(1M)
■
dig(1M)
■
resolv.conf(4)
■
domainname(1M)
Configuring the NFS Version 4 Default Domain
This section describes how the network obtains the desired default domain:
■
■
170
For most current releases, see “Configuring an NFS Version 4 Default Domain in the Oracle
Solaris 11 Release” on page 171.
For the initial Solaris 10 release, see “Configuring an NFS Version 4 Default Domain in the
Solaris 10 Release” on page 171.
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
NFS Daemons
Configuring an NFS Version 4 Default Domain in the Oracle Solaris 11
Release
In the Oracle Solaris 11 release, set the default NFS domain version by typing the following
command:
$ sharectl set -p nfsmapid_domain=example.com nfs
Note - Because of the inherent ubiquitous and scalable nature of DNS, the use of DNS TXT
records for configuring the domain of large NFS Version 4 deployments continues to be
preferred and strongly encouraged. See “nfsmapid and DNS TXT Records” on page 168.
Configuring an NFS Version 4 Default Domain in the Solaris 10 Release
In the initial Solaris 10 release of NFS Version 4, if your network included multiple DNS
domains but only had a single UID and GID namespace, all clients had to use one value for
nfsmapid_domain. For sites that use DNS, nfsmapid resolves this issue by obtaining the domain
name from the value that you assigned to _nfsv4idmapdomain. For more information, see
“nfsmapid and DNS TXT Records” on page 168. If your network is not configured to use
DNS, during the first system boot, the operating system uses the sysidconfig utility to provide
the following prompts for an NFS Version 4 domain name:
This system is configured with NFS Version 4, which uses a
domain name that is automatically derived from the system's
name services. The derived domain name is sufficient for most
configurations. In a few cases, mounts that cross different
domains might cause files to be owned by nobody due to the
lack of a common domain name.
Do you need to override the system's default NFS version 4 domain
name (yes/no)? [no]
The default response is [no]. If you choose [no], you see the following message:
For more information about how the NFS Version 4 default domain name is
derived and its impact, refer to the man pages for nfsmapid(1M) and
nfs(4), and the System Administration Guide: Network Services.
If you choose [yes], you see this prompt:
Enter the domain to be used as the NFS Version 4 domain name.
NFS Version 4 domain name []:
Note - If a value for nfsmapid_domain exists in the SMF repository, the domain name that you
provide overrides that value.
Chapter 7 • Accessing Network File Systems
171
NFS Daemons
Additional Information About nfsmapid
For more information about nfsmapid, see the following:
■
nfsmapid(1M) man page
■
■
nfs(4) man page
RFC 1464, Using the Domain Name System To Store Arbitrary String Attributes
■
“ACLs and nfsmapid in NFS Version 4” on page 37
reparsed Daemon
The reparsed daemon interprets the data associated with a reparse point. These points are used
by DFS and NFS referrals on SMB and NFS file servers. This service is managed by SMF and
should not be manually started.
statd Daemon
Note - NFS Version 4 does not use this daemon.
The statd daemon works with lockd to provide crash and recovery functions for the lock
manager. The statd daemon tracks the clients that hold locks on an NFS server. If a server
crashes, on rebooting, statd on the server contacts statd on the client. The client statd can
then attempt to reclaim any locks on the server. The client statd also informs the server statd
when a client has crashed so that the client's locks on the server can be cleared. This daemon
has no options. For more information, see the statd(1M) man page.
172
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
♦ ♦ ♦
A
A P P E N D I X
A
NFS File Sharing Command Reference
Administering Network File Systems
This table provides the basic command syntax for performing some common network file
sharing tasks in the Oracle Solaris 11.3 release. For more information, see the nfsref(1M),
nfsstat(1M), share(1M), and mount(1M) man pages.
Action
Command
Share a ZFS file
system
$
zfs set share.nfs=on | off filesystem
Define file systems
to use NFS server
logging
$
share -F nfs -o,log=global filesystem
List the shared NFS
file systems
$
share -F nfs
Mount a file system
$
mount -F nfs -o specific-options resource mount-point
Mount an NFS File
System by Using an
NFS URL
$
mount -F nfs nfs://host[:port]/pathname mount-point
Display information
about file systems
available for
mounting
$
/usr/sbin/showmount -e hostname
Select different
versions of NFS on a
server
$
$
sharectl set -p server_versmax=version_num nfs
sharectl set -p server_versmin=version_num nfs
Disable server
delegation
$
sharectl set -p server_delegation=off nfs
Set a common
domain for NFS
clients and servers
$
sharectl set -p nfsmapid_domain=domain_name nfs
Create an NFS
referral
$
nfsref add ref_filesystem server_name1:filesystem server_name2:filesystem
Appendix A • NFS File Sharing Command Reference
173
Troubleshooting Network File Systems
Action
Command
Remove an NFS
referral
$
nfsref remove ref_filesystem
Disable autofs
browsability on a
single NFS client
$
sharectl set -p nobrowse=TRUE autofs
Troubleshooting Network File Systems
This table provides the basic command syntax for some common NFS troubleshooting tasks in
the Oracle Solaris 11.3 release. For more information, see the nfsref(1M) and nfsstat(1M)
man pages.
174
Action
Command
Remove all file, record, and share locks for
an NFS client
$
clear_locks -s hostname
Display file system operations statistics by
file system type and by mount point
$
fsstat nfsversnum nfsversnum filesystem
Display NFS server statistics
$
nfsstat -s
Display the current NFS information
$
nfsstat -m
Display stack trace for NFS process
$
/usr/bin/pstack nfs_process_id
Display RPC service information for a host
$
rpcinfo -s hostname
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Index
Numbers and Symbols
# (pound sign)
comments in direct maps, 56
comments in indirect maps, 58
comments in master map (auto_master), 54
& (ampersand)
in autofs maps, 69
* (asterisk)
in autofs maps, 70
+ (plus sign)
in autofs map names, 66, 67
- (dash)
in autofs map names, 66
/ (slash)
/- as master map mount point, 54, 57
master map names preceded by, 54
root directory
mounting by diskless clients, 14
\ (backslash) in autofs maps, 54, 56, 58
A
-a option
showmount command, 131
umount command, 120
access control list (ACL) and NFS
description, 18
error message, Permission denied, 154
access control lists (ACLs) and NFS
description, 37
accessing
NFS referrals, 90
already mounted message, 148
ampersand (&)
in autofs maps, 69
anon option
share command, 126
applications
hung, 154
ARCH map variable, 65
asterisk (*)
in autofs maps, 70
authentication
DH, 47
Diffie-Hellman (DH), 47
RPC, 47
UNIX, 45, 47
auto_home map
/home directory, 100
/home directory server setup, 101
/home mount point, 53, 55
auto_master file
nobrowse option, 108
autofs
/home directory, 100
administering maps, 97
browsability, 22, 107
consolidating project-related files, 102
features, 22
home directory server setup, 101
maps
browsability and, 22
direct, 56, 57
indirect, 57, 59
master, 53, 54
network navigation, 53
175
Index
read-only file selection, 61, 64
referring to other maps, 66, 67
starting the navigation process, 55, 59
types of, 97
variables, 65, 65
metacharacters, 69, 70
mount process, 60, 61
mounting file systems, 77
namespace data, 22
NFS URL and, 107
nobrowse option, 108
non-NFS file system access, 100
overview, 14
public file handle and, 107
reference information for, 69, 70
replicating shared files across several servers, 106
shared namespace access, 104
special characters, 70
supporting incompatible client OS versions
using, 105
troubleshooting, 146
unmounting process, 61
automount command, 112
autofs and, 14
error messages, 146
modifying autofs master map (auto_master), 98
overview, 51
-v option, 146
when to run, 98
automountd daemon, 161
autofs and, 14
description, 22
mounting and, 22
overview, 51, 52
avoiding problems with ACLs in NFS, 38
B
background file-mounting option, 115
backslash (\) in maps, 54, 56, 58
bad argument specified with index option, 151
bad key message, 147
bg option
176
mount command, 115
booting
diskless client security, 48
mounting file systems, 75
browsability
disabling, 107
overview, 22
browsing
with an NFS URL, 89
C
cache and NFS Version 3, 16
can't mount message, 147
cannot receive reply message, 149
cannot send packet message, 149
checking for unmapped user or group IDs, 38
clear_locks command, 113
client recovery
NFS Version 4, 33
client-side failover
enabling, 77
in NFS Version 4, 42
NFS locking and, 42
NFS support, 20
overview, 41
replicated file systems, 42
client_versmax parameter, 163
client_versmin parameter, 163
commands
FedFS, 132
hung programs, 154
NFS, 111
comments
in direct maps, 56
in indirect maps, 58
in master map (auto_master), 54
consolidating project-related files, 102
conversation key, 47
could not use public filehandle message, 151
couldn't create mount point message, 147
CPU map variable, 65
creating
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Index
namespace database (FedFS), 92
NFS referrals, 50, 90, 94
secure connection (FedFS), 93
credentials
description, 46
UNIX authentication, 47
D
-d option
showmount command, 131
daemon running alreadymessage, 151
daemons
automountd, 161
autofs and, 14
overview, 51, 52
lockd, 162
mountd, 163
checking response on server, 143
not registered with rpcbind daemon, 152
verifying if running, 144, 152
nfs4cbd, 164
nfsd
checking response on server, 142
description, 164
verifying if running, 144
nfslogd, 165
nfsmapid, 165
reparsed, 172
required for remote mounting, 133
rpcbind
mount error messages, 152, 152
statd, 172
dash (-)
in autofs map names, 66
delegation
NFS Version 4, 35
DH authentication
overview, 47, 47
password protection, 46
secure NFS and, 85
user authentication, 45
dir must start with '/'message, 148
direct I/O mounting option, 115
direct maps (autofs)
comments in, 56
description, 98
example, 56
overview, 57
syntax, 56
when to run automount command, 98
disabling
autofs browsability
overview, 107
mount access for one client, 78
diskless clients
manual mounting requirements, 14
security during boot process, 48
displaying
mountable file systems, 80
restricted file system information, 80
DNS record
FedFS, 91
domain names
Secure NFS system and, 85
domains
definition, 85
E
/etc/default/autofs file
configuring autofs environment, 97
/etc/default/nfslogd file, 158
/etc/mnttab file
comparing with auto_master map, 52
/etc/netconfig file, 158
/etc/nfs/nfslog.conf file, 159
/etc/services file
nfsd entries, 151
/etc/vfstab file
automount command and, 53
diskless clients, 14
enabling client-side failover, 78
mounting file systems at boot time, 75
177
Index
NFS servers and, 75
-e option
showmount command, 131
enabling
client-side failover, 77
NFS server logging, 73
WebNFS service, 88
error checking message, 152
error locking message, 151
error messages
generated by automount -v command, 146
miscellaneous automount messages, 148
No such file or directory, 152
open errors
NFS and, 16
Permission denied, 153
server not responding
hung programs, 154
keyboard interrupt for, 133
remote mounting problems, 152, 154
write errors
NFS and, 16
executable maps, 67
F
-F option
unshareall command, 130
failover
error message, 152
mount command example, 118, 118
NFS support, 20
Federated File System See FedFS
FedFS
administering, 91
DNS record for, 91
LDAP schema, 92
mount point, 55
mounting, 91
FedFS commands, 132
fg option
mount command, 115
178
file attributes and NFS Version 3, 16
file permissions
NFS Version 3 improvement, 16
WebNFS and, 88
File Sharing
NFS Commands, 173
file sharing
automatic, 72
examples, 128
giving root access, 127
listed clients only, 125
multiple file systems, 130
NFS Version 3 improvements, 16, 19
overview, 124
read-only access, 125, 125, 128
read-write access, 125, 128
replicating shared files across several servers, 106
security issues, 45, 125, 127
unauthenticated users and, 126
unsharing, 130
file system namespace
NFS Version 4, 29
file systems and NFS, 15
file too large message, 152
file transfer size
negotiation, 39
file-sharing options, 125
files and file systems
autofs access
non-NFS file systems, 100
autofs selection of files, 61, 64
consolidating project-related files, 102
definition, 15
file systems , 15
local file systems
unmounting groups, 121
NFS files and their functions, 157
NFS treatment of, 15, 15
remote file systems
listing clients with remotely mounted file
systems, 131
mounting from file system table, 121
unmounting groups, 121
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Index
firewalls
mounting file systems through, 79
NFS access through, 21
WebNFS access through, 90
forcedirectio option
mount command, 115
foreground file-mounting option, 115
ftp archive
WebNFS and, 88
fuser command
umountall command and, 121
G
-g option
lockd daemon, 162
grace_period parameter
lockd daemon, 162
GSS-API
and NFS, 20
H
/home directory and NFS server setup, 101
/home mount point, 53, 55
-h option
umountall command, 121
hard option
mount command, 117
hierarchical mount points message, 148
hierarchical mounts (multiple mounts), 60
HOST map variable, 65
host not responding message, 148
hosts
unmounting all file systems from, 121
HTML file
WebNFS and, 88
httpd command
firewall access and WebNFS, 90
hung programs, 154
I
ID mapping fails
reasons why, 37
index option
bad argument error message, 151
share command, 89
WebNFS and, 88
indirect maps (autofs)
comments in, 58
description, 98
example, 58, 59
overview, 57, 59
syntax, 57, 58
when to run automount command, 98
-intr option
mount command, 133
K
/kernel/fs file
checking, 157
-k option
umountall command, 121
KERB authentication
NFS and, 20
kernel
checking response on server, 141
keyboard interruption of mounting, 133
keylogin command
remote login security issues, 48
keylogout command
secure NFS and, 48
keywords
NFS Version negotiation, 28
L
-l option
umountall command, 121
large files
NFS support, 19
largefiles option
179
Index
error message, 153
mount command, 115
LDAP schema
for FedFS, 92
leading space in map entry message, 147
listing
clients with remotely mounted file systems, 131
mounted file systems, 119
shared file systems, 128
local cache and NFS Version 3, 16
local file systems
unmounting groups, 121
local files
updating autofs maps, 98
lockd daemon, 162
LOCKD_GRACE_PERIOD parameter
lockd daemon, 162
lockd_retransmit_timeout parameter
lockd daemon, 162
lockd_servers parameter
lockd daemon, 163
locking
NFS Version 3 improvements, 19
log option
share command, 126
login command
secure NFS and, 48
ls command
ACL entries and, 37
M
map key bad message, 149
maps (autofs)
administrative tasks, 97
automount command
when to run, 98
avoiding mount conflicts, 99
comments in, 54, 56, 58
direct, 56, 57
executable, 67
indirect, 57, 59
180
maintenance methods, 98
master, 53, 54
multiple mounts, 60
network navigation, 53
referring to other maps, 66, 67
selecting read-only files for clients, 61, 64
special characters in, 70
splitting long lines in, 54, 56, 58
starting the navigation process, 55, 59
types and their uses, 97
variables, 65, 65
master map (auto_master)
/- mount point, 53, 57
comments in, 54
comparing with /etc/mnttab file, 52
contents, 53, 55
description, 98
overview, 53, 54
preinstalled, 100
security restrictions, 106
syntax, 54
when to run automount command, 98
mirror mounts
mounting all file systems from one server, 77
overview, 49
mnttab file
comparing with auto_master map, 52
modifying
NFS referrals, 91
mount command, 114
autofs and, 14
diskless clients' need for, 14
failover with, 118, 118
manually mounting file systems, 76
NFS URL, 80
NFS URL with, 118
options
description, 115
no arguments, 119
public, 79
using, 117
mount of server:pathname error, 149
mount points
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Index
/- as master map mount point, 53, 57
/home, 53, 55
/net, 55
/nfs4, 53, 55
avoiding conflicts, 99
mountall command, 121
mountd daemon, 163
checking response on server, 143
not registered with rpcbind, 152
verifying if running, 144, 152
mounting
all file systems in a table, 121
autofs and, 14, 61
background retries, 115
diskless client requirements, 14
examples, 117
FedFS, 91
force direct I/O, 115
foreground retries, 115
keyboard interruption during, 133
mirror mounts and, 49
nfsd daemon and, 39
overlaying already mounted file system, 118
portmapper and, 39
public file handle and, 40
read-only specification, 117, 117
read-write specification, 117
remote mounting
daemons required, 133
troubleshooting, 141, 144
soft compared to hard, 133
mounting file systems
autofs and, 77
boot time method, 75
disabling access for one client, 78
manually (on the fly), 76
mounting all from one server, 77
NFS URL with, 79
overview, 74
task map, 74
through a firewall, 79
N
/net mount point, 55
/nfs4 mount point, 53, 55
namespaces
accessing shared, 104
autofs and, 22
naming services
autofs map maintenance methods, 98
navigating using maps
overview, 53
starting the process, 55, 59
negotiation
file transfer size, 39
WebNFS security, 21
netconfig file
description, 158
Network Lock Manager, 19
NFS
commands, 111
daemons, 160
version negotiation, 28
NFS ACL
description, 18, 37
error message, Permission denied, 154
NFS administration
administrator responsibilities, 71, 95
NFS can't support nolargefiles message, 153
NFS clients
incompatible operating system support, 105
NFS services, 15
NFS environment
Secure NFS system, 45
NFS locking
client-side failover and, 42
NFS referrals
creating, 90, 94
overview, 50
removing, 91
NFS server logging
enabling, 73
overview, 21
NFS servers
autofs selection of files, 64
181
Index
daemons required for remote mounting, 133
identifying current, 145
maintaining, 71, 95
replicating shared files, 106
troubleshooting
clearing problems, 141
remote mounting problems, 140, 153
weighting in maps, 65
NFS services
restarting, 145
selecting different versions on client by
changing the SMF properties, 83
using the mount command, 84
selecting different versions on server, 82
task map, 81
NFS troubleshooting
determining where NFS service has failed, 144
hung programs, 154
remote mounting problems, 153
server problems, 141
strategies, 133
NFS URL
autofs and, 107
mount command example, 118
mounting file systems with, 79
mounting with, 21
syntax, 89
WebNFS and, 88
NFS V2 can't support largefiles message, 153
NFS Version 4
features in, 28
nfs4cbd daemon, 164
nfscast: cannot receive reply message, 149
nfscast: cannot send packet message, 149
nfscast: select message, 150
nfsd daemon, 164
checking response on server, 142
mounting and, 39
verifying if running, 144
nfslog.conf file, 159
nfslogd daemon
description, 165
nfslogd file, 158
182
nfsmapid daemon
ACLs and, 37
additional information about, 172
configuration files and, 167
configuring the NFSv4 default domain, 170
description, 17, 165
DNS TXT records and, 168
identifying NFSv4 domain, 169
precedence rules and, 167
NFSMAPID_DOMAIN keyword, 38
nfsmapid_domain parameter, 166
nfsref command
description, 132
example, 94
nfsstat command, 134, 145
NIS name service
updating autofs maps, 98
no info message, 150
No such file or directory message, 152
nobrowse option
auto_master file, 108
nobrowse parameter
setting, 108
nolargefiles option
error message, 153
mount command, 115
nosuid option
share command, 126
Not a directory message, 149
Not found message, 147
nsdb-list command
description, 132
nsdb-nces command
description, 132
nsdb-resolve-fsn command
description, 132
nsdb-update-nci command
description, 132
example, 92
nsdbparams command
description, 132
example, 93
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Index
nthreads option
lockd daemon, 163
number sign (#)
comments in direct maps, 56
comments in indirect maps, 58
comments in master map (auto_master), 54
O
-O option
mount command, 118
-o option
mount command, 117
share command, 125, 128
open errors
NFS and, 16
OPEN share support
NFS Version 4, 34
operating systems
map variables, 65
supporting incompatible versions, 105
OSNAME map variable, 65
OSREL map variable, 65
OSVERS map variable, 65
overlaying already mounted file system, 118
P
passwords
autofs and superuser passwords, 14
DH password protection, 46
pathconf: no info message, 150
pathconf: server not responding message, 150
Permission denied message, 153
permissions
NFS Version 3 improvement, 16
plus sign (+)
in autofs map names, 66, 67
portmapper
mounting and, 39
pound sign (#)
comments in direct maps, 56
comments in indirect maps, 58
comments in master map (auto_master), 54
printing
list of remotely mounted directories, 131
list of shared or exported files, 131
problems with ACLs in NFS
avoiding, 38
processor type map variable, 65
programs
hung, 154
projects
consolidating files, 102
pstack command, 136
public file handle
autofs and, 107
mounting and, 40
NFS mounting with, 21
WebNFS and, 88
public option
in dfstab file, 89
mount command, 79, 116
share error message, 155
WebNFS and, 88
public-key cryptography
common key, 47
conversation key, 47
database of public keys, 46, 47
DH authentication, 47, 47
secret key
database, 47
deleting from remote server, 48
time synchronization, 47
public-key map
DH authentication, 47
R
-r option
mount command, 117
umountall command, 121
read-only type
file selection by autofs, 61, 64
mounting file systems as, 117, 117
183
Index
sharing file systems as, 125, 125, 128
read-write type
mounting file systems as, 117
sharing file systems as, 125, 128
referrals See NFS referrals
remote file systems
listing clients with remotely mounted file
systems, 131
unmounting groups, 121
remote mounting
daemons required, 133
troubleshooting, 140, 144
Remote Procedure Call (RPC)
Secure
overview, 46
remount message, 148
removing
NFS referrals, 51, 91
removing locks, 113
reparsed daemon, 172
replicas must have the same version
message, 155
replicated file system, 42
replicated mounts
soft option and, 155
replicated mounts must be read-only
message, 155
replicated mounts must not be soft
message, 155
replicating shared files across several servers, 106
restricting
displayed file system information, 80
rlogin command
secure NFS and, 48
ro option
mount command, 117
mount command with -o flag, 117
share command, 125, 128
root directory
mounting by diskless clients, 14
root option
share command, 127
RPC
184
authentication, 47
Secure
DH authorization issues, 48, 48
rpcbind daemon
dead or hung, 152
mountd daemon not registered, 152
rpcinfo command, 137
RPCSEC_GSS, 20
rw option
mount command, 117
share command, 125, 128
rw=client option
umountall command, 125
S
-s option
umountall command, 121
secret key
database, 47
deleting from remote server, 48
server crash and, 48, 48
Secure NFS system
administering, 85
DH authentication and, 85
domain name, 85
overview, 45
Secure RPC
DH authorization issues, 48, 48
overview, 46
security
applying autofs restrictions, 107
DH authentication
overview, 47, 47
password protection, 46
user authentication, 45
file-sharing issues, 125, 127
NFS Version 3 and, 16
Secure NFS system
administering, 85
overview, 45
Secure RPC
DH authorization issues, 48, 48
Managing Network File Systems in Oracle Solaris 11.3 • October 2017
Index
overview, 46
UNIX authentication, 45, 47
security and NFS
description, 18, 37
error message, Permission denied, 154
security flavors, 20
security mode selection and mount command, 117
serial unmounting, 121
server not responding message, 148, 150
hung programs, 154
keyboard interrupt for, 133
remote mounting problems, 152
server_delegation parameter, 165
server_versmax parameter, 165
server_versmin parameter, 164
servers, 106
See also NFS servers
autofs selection of files, 61
crashes and secret keys, 48, 48
home directory server setup, 101
NFS servers and vfstab file, 75
NFS services, 15
servers and clients
NFS service, 15
setfacl command
NFS and, 37
setgid mode
share command, 126
setting
nobrowse parameter, 108
setuid mode
Secure RPC and, 48
share command, 126
share command
description, 124
enabling WebNFS service, 89
options, 125
security issues, 127
shareall command, 130
sharing See file sharing
showmount command, 131
example, 80
showmount_info property, 80
single-user mode and security, 48
slash (/)
/- as master map mount point, 53, 57
master map names preceded by, 54
root directory, mounting by diskless clients, 14
snoop command, 139
soft option
mount command, 117
special characters in maps
enclosing in quotation marks, 70
statd daemon, 172
superusers
autofs and passwords, 14
synchronizing time, 47
T
-t option
lockd daemon, 162
TCP
NFS Version 3 and, 18
telnet command
secure NFS and, 48
time synchronization, 47
transport protocol
NFS negotiation, 38
transport setup problem
error message, 151
Troubleshooting
NFS Commands, 174
troubleshooting
autofs, 146
avoiding mount point conflicts, 99
error messages generated by automount -v
command, 146
miscellaneous error messages, 148
NFS
determining where NFS service has failed, 144
hung programs, 154
remote mounting problems, 140, 153
server problems, 141
strategies, 133
truss command, 140
185
Index
U
/usr directory
mounting by diskless clients, 14
/usr/kvm directory
mounting by diskless clients, 14
/usr/lib/fs/nfs/fedfs-11.schema file, 92
/usr/sbin/mount command See mount command
/usr/sbin/nsdb-list command
description, 132
/usr/sbin/nsdb-nces command
description, 132
/usr/sbin/nsdb-resolve-fsn command
description, 132
/usr/sbin/nsdb-update-nci command
description, 132
/usr/sbin/nsdbparams command
description, 132
/usr/sbin/showmount command, 131
/usr/sbin/unshareall command, 130
UDP
NFS and, 19
umount command
autofs and, 14
description, 120
umountall command, 121
UNIX authentication, 45, 47
unmapped user or group IDs
checking for, 38
unmounting
autofs and, 14, 61
examples, 120
groups of file systems, 121
mirror mounts and, 49
unshare command, 129
unshareall command, 130
unsharing and resharing
NFS Version 4, 29
unsharing file systems
unshare command, 129
unshareall command, 130
URL service types
WebNFS and, 90
186
V
-V option
umount command, 120
-v option
automount command, 146
variables in map entries, 65, 65
verifiers
RPC authentication system, 46
version negotiation
NFS, 28
vfstab file
automount command and, 53
enabling client-side failover, 78
mounting by diskless clients, 14
mounting file systems at boot time, 75
NFS servers and, 75
volatile file handles
NFS Version 4, 32
W
WARNING: mountpoint already mounted on
message, 148
WebNFS service
browsing, 89
description, 43
enabling, 88
firewalls and, 90
overview, 20
planning for, 87
security negotiations and, 21
task map, 87
URL service types and, 90
weighting of servers in maps, 65
write errors
NFS and, 16
Managing Network File Systems in Oracle Solaris 11.3 • October 2017