File system and fileset backups with IBM Storage Protect

mmbackup supports backup from independent filesets in addition to backup of the whole file system. Independent filesets have similar capabilities as a file system in terms of quota management, dependent filesets, snapshots, and having their own inode space.

Fileset mmbackup provides a finer granularity for backup purposes and permits the administrator to:

  • Have different backup schedules for different filesets. For example, providing the flexibility that filesets containing more important data to be backed up more often than other filesets.

  • Have a fileset dedicated for temporary or transient files or files that do not need to be backed up.

  • Use file system backups in conjunction with fileset backup to implement a dual data protection scheme such that file system backup goes to one IBM Storage Protect server while fileset backup goes to a different IBM Storage Protect server.

Backups of file systems and independent filesets are controlled by using the mmbackup option --scope.

In the examples used in this topic, the following environment is assumed:

tsm server name             => tsm1,tsm2,...
file system device name     => gpfs0 or /dev/gpfs0
file system mountpoint      => /gpfs0

fileset names/junction path
--------------------------- 
depfset1,depfset2,...     /gpfs0/depfset1,/gpfs0/depfset2         for dependent filesets
indepfset1,indepfset2,... /gpfs0/indepfset1,/ibm/gpfs0/indepfset2 for indepdendent filesets

File system backup

File system backup protects the whole file system. The default value for option --scope is filesystem and thus it can be omitted.

To back up the gpfs0 file system in its entirety to the IBM Storage Protect server named tsm1, use the following command:

mmbackup gpfs0 --tsm-servers tsm1
mmbackup gpfs0 --tsm-servers tsm1 --scope filesystem
mmbackup /dev/gpfs0 --tsm-servers tsm1
mmbackup /dev/gpfs0 --tsm-servers tsm1 --scope filesystem
mmbackup /gpfs0 --tsm-servers tsm1
mmbackup /gpfs0 --tsm-servers tsm1 --scope filesystem

This example shows the file system backup of gpfs0 using the short or long device name (first 4 lines) or the mount point as a directory input (last 2 lines).

Independent fileset backup

Independent fileset backup protects all files that belong to the inode space of a single independent fileset. The backup of an independent fileset might include other dependent filesets and folders, but not nested independent filesets because each independent fileset has its own inode space.

The following information describes the mmbackup capability to support independent fileset. The examples with IBM Storage Protect show the potential/likely use of this capability.

To back up the independent fileset indepfset1 of the file system gpfs0 to IBM Storage Protect server named tsm1, use the following command:

mmbackup /gpfs0/indepfset1 --tsm-servers tsm1 --scope inodespace

Fileset backup is an additional option to existing IBM Storage Scale backup or data protection options. Therefore, starting with a file system in which the whole file system has already been backed up on a regular basis, administrators can also start protecting data with fileset backup on some or all filesets. Administrators may choose to utilize fileset backup at any time, with no limit. It is not required to back up the whole file system in either one mode or another unless the chosen data protection approach requires it. Also, administrators can choose different IBM Storage Protect servers for some or all fileset backups if it is desired to have these on separate servers. For example, a valid configuration may have one IBM Storage Protect server that only gets whole file system backups, and a different one for fileset backups.

Note: When mixing file system and fileset backup on the same IBM Storage Protect server, consider that a target file that is handled by both backup approaches gets backed up twice. Each backup activity consumes one storage version of the file. Thus, the same file version is stored twice on the IBM Storage Protect server.

If migrating to use only fileset backup to protect the whole file systems, ensure that all independent filesets are backed up and keep the backup of all filesets current. Remember to include a backup of the root fileset as well by using a command such as:

mmbackup /gpfs/gpfs0 --scope inodespace --tsm-servers tsm1

To verify the completeness of the data protection using fileset backup only, use the following steps:

  1. Identify all independent filesets available in the file system by using the following command:

    mmlsfileset device -L

    Identify the independent filesets by the InodeSpace column. The value identifies the corresponding inode space or independent fileset while the first occurrence refers to the corresponding fileset name and fileset path.

    Note: Ensure that a backup is maintained of the fileset called root that is created when the file system is created and that can be seen as the first fileset of the file system.
  2. For every identified independent fileset, verify that a shadow database exists as follows:
    1. Check for the file .mmbackupShadow.<digit>.<TSMserverName>.fileset in the fileset junction directory.
    2. If the file exists, determine the time of last backup by looking at the header line of this file. The backup date is stored as last value of this line.

      For example: 

      head -n1 /gpfs0/indepfset1/.mmbackupShadow.*.fileset
%%mshadow0%%:00_BACKUP_FILES_41:1400:/gpfs0:mmbackup:1:Mon Apr 20 13:48:45 2015

      Where Mon Apr 20 13:48:45 2015 in this example is the time of last backup taken for this fileset.

  3. If any independent filesets are missing their corresponding .mmbackupShadow.* files, or if they exist but are older than the data protection limit for their backup time, then start or schedule a backup of these filesets.
    Note: This action needs to be done for every file system for which the fileset backup approach is chosen.
Note: Backup of a nested independent fileset is not supported. To work around this limitation, unlink the nested fileset and link it at another location in the root fileset prior to beginning to use fileset backup pervasively.