automount

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, and -v selects the verbose mode. Running this command in the verbose mode allows for easier troubleshooting.

If not specifically set, the value for duration is set to 5 minutes. In most circumstances, this is a good value. 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 (or 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.

Another factor to consider is 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" for instructions on how to modify automounter maps.

clear_locks

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 the NFS client named tulip on the current system.

# clear_locks tulip

Using the -s option enables you to specify which NFS host to clear the locks from. You must run this option from the NFS client, which created the locks. In this situation, the locks from the client would be removed from the NFS server named bee.

# clear_locks -s bee

Caution - This command should only be run when a client crashes and cannot clear its locks. To avoid data corruption problems, do not clear locks for an active client.

mount

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.

Many types of file systems are included in the standard Solaris installation. Each file-system type has a specific man page that lists the options to mount that are appropriate for that file-system type. The man page for NFS file systems is mount_nfs(1M). For UFS file systems, see mount_ufs(1M).

The Solaris 7 release includes the ability to 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 Using an NFS URL" for further information.

Caution - The version of the mount command included in any Solaris release from 2.6 to the current release, does not warn about options that are not valid. The command silently ignores any options that cannot be interpreted. Ensure that you verify all of the options that were used to prevent unexpected behavior.

mount Options for NFS File Systems

The subsequent text lists some of the options that can follow the -o flag when you are mounting an NFS file system.

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. This option prevents further processing until the mount is complete. -bg is a good selection for file systems that are not critical, because the client can do other processing while waiting for the mount request to complete.

forcedirectio

This option improves performance of sequential reads on large files. Data is copied directly to a user buffer and no caching is done in the kernel on the client. This option is off by default.

largefiles

This option makes it possible to access files larger than 2 Gbytes on a server that is running the Solaris 2.6 release. 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. Starting with release 2.6, 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 exist or will exist on the file system (see the mount_ufs(1M) man page). Because the existence of large files can only be controlled 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.

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 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 read-only. 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 read-only 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 value for mode can be one of the values that is shown in Table 16-2. The modes are also defined in /etc/nfssec.conf.

Table 16-2 NFS Security Modes

Mode	Selected Authentication Service
krb5	Kerberos Version 5
krb5i	Kerberos Version 5 with integrity
krb5i	Kerberos Version 5 with privacy
none	No authentication
dh	Diffie-Hellman (DH) authentication
sys	Standard UNIX authentication

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 if the soft option is used. 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

Both of these commands mount an NFS file system from the server bee read-only:

# mount -F nfs -r bee:/export/share/man /usr/man

# mount -F nfs -o ro bee:/export/share/man /usr/man

This command uses the -O option to force the man pages from the server bee to be mounted on the local system even if /usr/man has already been mounted as follows:

# mount -F nfs -O bee:/export/share/man /usr/man

This command uses client failover:

# mount -F nfs -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 mix version 2 and version 3 servers when running mount from the command line. You can use mixed servers with autofs. Autofs automatically selects the best subset of version 2 or version 3 servers.

Here is an example of using an NFS URL with the mount command:

# mount -F nfs nfs://bee//export/share/man /usr/man

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 Tues Jan 24 13:20:47 1995
/usr on /dev/dsk/c0t3d0s6 read/write/setuid on Tues Jan 24 13:20:47 1995
/proc on /proc read/write/setuid on Tues Jan 24 13:20:47 1995
/dev/fd on fd read/write/setuid on Tues Jan 24 13:20:47 1995
/tmp on swap read/write on Tues Jan 24 13:20:51 1995
/opt on /dev/dsk/c0t3d0s5 setuid/read/write on Tues Jan 24 13:20:51 1995
/home/kathys on bee:/export/home/bee7/kathys              
  intr/noquota/nosuid/remote on Tues Jan 24 13:22:13 1995

umount

This command enables you to remove a remote file system that is currently mounted. The umount command supports the -V option to allow for testing. You might also use the -a option to umount 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.

The -f option 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.

Using the umount Command

This example unmounts a file system that is mounted on /usr/man:

# umount /usr/man

This example displays the results of running umount -a -V:

# umount -a -V
umount /home/kathys
umount /opt
umount /home
umount /net

Notice that this command does not actually unmount the file systems.

mountall

Use this command to mount all file systems or a specific group of file systems that are listed in a file-system table. The command provides a way to do the following:

• Select the file-system type to be accessed with the -F FSType option

• Select all the remote file systems that are listed in a file-system table with the -r option

• Select all the local file systems with the -l option

Using the mountall Command

These two examples are equivalent:

# mountall -F nfs

# mountall -F nfs -r

umountall

Use this command to unmount a group of file systems. The -k option runs the fuser -k mount_point command to kill any processes that are associated with the mount_point. The -s option indicates that unmount is not to be performed in parallel. -l specifies that only local file systems are to be used, and -r specifies that only remote file systems are to be used. The -h host option indicates that all file systems from the named host should be unmounted. You cannot combine the -h option with -l or -r.