TSM - Library Tape Management

Moving Tapes offsite

There are two parts to volume movement, updating TSM so its knows what is happening with the volumes; and physically managing the automated library inventory by using checkin/checkout commands.

If you are planning to take tapes offsite to a vault, then the important step is to update the access mode of those volumes to 'OFFSITE'. This tells TSM that it can still so some data processing like Reclamation and Move Data commands, but it will NEVER request a mount of the actual volume (it uses the primary copy instead). Note that only copy pool volumes can be set to 'OFFSITE' - this is because TSM always expects to have its primary pool volumes available (i.e.:mountable). The checkout operation for the offsite copypool volumes is a necessary extra step to get the tapes out of the library inventory.

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Freeing up library slots

If your library becomes full, you may need to free up some slots. The trick is to eject older tapes from the library that you are not likely to use for a while, and keep the active tapes in the library. The 'MOVE MEDIA' command gives us the ability to have a combination automatic/manual library. We can 'move' tapes outside of the library to a nearby 'location', but the tapes are still considered as mountable. The distinction is whether they have the media state of 'MOUNABLEINLIB' or 'MOUNTABLENOTINLIB', and this tells TSM whether to ask the robot for to mount the volume or to issue a manual mount request. When processing an manual mount request, you must use the 'Checkin Libvol' command to update the library inventory and tell TSM that the tape is back in the robot (since that is ultimately how the tape gets mounted).

TSM will automatically toggle the volume's access mode from ReadOnly to ReadWrite and back again as it is moved in and out of the library. This is to allow any read operations to proceed (e.g.: restore) and cause a manual mount request, but write operations will not attempt to access the volume.

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Reclaiming offsite tapes

You don't have to bring your offsite tapes in to do reclamation.

Set your copypool reclamation to a reasonable level, say 60%. TSM knows what files are still valid on offsite volumes that are to be reclaimed. It finds the copies of those files in the primary storage pool (which is still in the library); it moves a scratch tape to the copy pool and copies the files from the primary tape pool to the new copypool tape. The new copy tape is then marked to go offsite, and the old one marked for return.

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Reporting on Tape usage

The following query will produce a report of the space usage of all storage pool volumes, summarised by storage pool and status.

 SELECT STGPOOL_NAME AS STGPOOL, 
  COUNT(VOLUME_name) AS COUNT, STATUS, 
  CAST(MEAN(EST_CAPACITY_MB/1024) 
   AS DECIMAL(5,2)) AS GB_PER_VOL 
 FROM VOLUMES 
 GROUP BY STGPOOL_NAME,STATUS

Example output is shown below

 STGPOOL              COUNT     STATUS        GB_PER_VOL
 -------------  -----------     ---------     ----------
 ARCHCOPYPOOL           417     FULL                1.10
 ARCHIVEPOOL              2     ONLINE              2.78
 ARCHTAPEPOOL             2     FILLING            27.58
 ARCHTAPEPOOL             2     FULL               49.60
 BACKUPPOOL               7     ONLINE             38.26
 CARTPOOL                 1     EMPTY               0.00
 CARTPOOL               221     FILLING            22.01
 CARTPOOL              1021     FULL               33.99

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