Some tips and techniques for managing GPFS file systems

Mount a file system on some nodes

Set special mount options for a specific node

Specify mount order (GPFS Version 3.4 or later only)

MOUNT A FILE SYSTEM ON SOME NODES

If you do not want any file systems that are configured for automount to be mounted on a specific node. On that node create the file  /var/mmfs/etc/ignoreStartupMount

#echo "some text" > /var/mmfs/etc/ignoreStartupMount

If you want to mount some of the file system that are configured for automount create a /var/mmfs/etc/ignoreStartupMount file for each file system by adding a “.devicename” to the end of the file.

#echo "some text" > /var/mmfs/etc/ignoreStartupMount.<devicename>

For example if you have file systems fs1 and fs1 configured for automount and you do not want to mount fs2 on this node you would create a file called “/var/mmfs/etc/ignoreStartupMount.fs2″

#echo "some text" /var/mmfs/etc/ignoreStartupMount.fs2

(With a period between the keyword and the device name)

If you do not want the file system to mount at all instead of using ignoreStartupMount you can create an ignoreAnyMount file using the same syntax. This keeps the file system from being mounted on this node when mmmount is used in addition to not mounting on startup.

SET SPECIAL MOUNT OPTIONS FOR A SPECIFIC NODE

You may want to set special file system mount options for a specific node. To set special mount options create a file called /var/mmfs/etc/localMountOptions.$fsname where $fsname is the name of the file system. You can create a file for each file system that requires special mount options.

The file /var/mmfs/etc/localMountOptions.$fsname contains a single line with the mount options you wish to use. The mount options available are the same as your operating system mount options for the mount commands -o flag.

For example, to mount the file system fs1 as read only, start by creating a file.

/var/mmfs/etc/localMountOptions.fs1 ,That contains the value ro in the first line of the file.If you want all the file system on a particular node to mount with the same options create a file without the file system name at the end that contains a single line of text with the desired mount options.

/var/mmfs/etc/localMountOptions

SPECIFY MOUNT ORDER

You may want to set the order of file system mounts when the daemon starts and successfully joins the cluster (if mmlsconfig autoload shows yes) or when a mmount all command is executed. This is especially useful when you have nested GPFS file systems.

To do so, use the –mount-priority NumericPriority option on the mmcrfs, mmchfs or mmremotefscommands.