Working with File System Labels

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(Updated: Sep 2009)

The file system name is limited to 8 characters so that file system and target information can be encoded in the disk label. This allows system administrators to "mount by label", reducing the risk of SCSI disk reordering or getting the /dev/device wrong for a shared target.

Linux disk labels are limited to 16 characters. To identify the target within the file system, 8 characters are reserved, leaving 8 characters for the file system name:

<fsname>-MDT0000 or <fsname>-OST0a19

To mount by label, use this command:

$ mount -t lustre -L <file system label> <mount point>

Here is an example of mounting by label:

$ mount -t lustre -L testfs-MDT0000 /mnt/mdt

Caution: Mounting by label should NOT be used in a multi-path environment.

Although the file system name is internally limited to 8 characters, you can mount the clients at any mount point, so file system users are not limited to using short names. Here is an example:

mount -t lustre uml1@tcp0:/shortfs /mnt/<long-file_system-name>