RECLAIM STGPOOL (Reclaim volumes in a sequential-access storage pool)

For storage pools that use a Write Once Read Many (WORM) device class, reclamation is not necessary because WORM volumes are not reusable. However, you can run reclamation to consolidate data onto fewer volumes. Volumes that are emptied by reclamation can be checked out of the library, freeing slots for new volumes.

This command can be used only with sequential access storage pools. The storage pool data format cannot be NETAPPDUMP, CELERRADUMP, or NDMPDUMP. Storage pools that are defined with a CENTERA device class cannot be reclaimed.

Use this command only if you are not going to use automatic reclamation for the storage pool. You can set the RECLAIM parameter of the storage pool definition to 100 to prevent automatic reclamation from running. This command accepts the values of the RECLAIMPROCESS and RECLAIMSTGPOOL attributes of the storage pool definition. This command also accepts the values of the OFFSITERECLAIMLIMIT and RECLAIM parameters of the storage pool definition, if not overridden by the OFFSITERECLAIMLIMIT and THRESHOLD command parameters. Use caution when you set the value of the RECLAIM parameter of an active-data pool to 100. Doing so prevents the removal of inactive versions of backup data.

This command creates one or more reclamation processes that can be canceled with the CANCEL PROCESS command. The number of processes is limited by the RECLAIMPROCESS attribute of the storage pool definition. To display information about background processes, use the QUERY PROCESS command.

Privilege class

To issue this command, you must have system privilege, unrestricted storage privilege, or restricted storage privilege for the storage pool being reclaimed and the reclaim storage pool, if applicable.

Parameters

pool_name (Required)

Specifies the storage pool in which volumes are to be reclaimed.

DUration

Specifies the maximum number of minutes that the reclamation runs before being automatically canceled. You can specify a number from 1 to 9999. This parameter is optional.

After the specified number of minutes elapses, the next time the server checks the reclamation process the server stops the reclamation process. The server checks the reclamation process when the server mounts another eligible volume from the storage pool being reclaimed, and when the server begins to reclaim a new batch of files from the currently mounted volume. As a result, the reclamation can run longer than the value you specified for this parameter.

Until the server checks the reclamation process, there is no indication that the duration period has expired. When the server stops the reclamation process, the server issues message ANR4927W: Reclamation terminated for volume xxx - duration exceeded.

If you do not specify this parameter, the process stops only when no more volumes meet the threshold.

If you specify a duration value for reclamation of a copy storage pool with offsite volumes, you might cause the reclamation to terminate before any volumes are reclaimed. In most situations when initiating reclamation for a copy storage pool with offsite volumes, consider limiting the number of offsite volumes to be reclaimed rather than limiting the duration. For details, see the OFFSITERECLAIMLIMIT parameter.

THreshold

Specifies the percentage of reclaimable space that a volume must have to be eligible for reclamation. Reclaimable space is the amount of space that is occupied by files that are expired or deleted from the Tivoli® Storage Manager database. Reclaimable space also includes unused space.

You can specify a number from 1 to 99. This parameter is optional. If not specified, the RECLAIM attribute of the storage pool definition is used.

When determining which volumes in a storage pool to reclaim, the Tivoli Storage Manager server first determines the reclamation threshold. The server then examines the percentage of reclaimable space for each volume in the storage pool. If the percentage of reclaimable space on a volume is greater that the reclamation threshold of the storage pool, the volume is a candidate for reclamation.

For example, suppose that storage pool FILEPOOL has a reclamation threshold of 70 percent. This value indicates that the server can reclaim any volume in the storage pool that has a percentage of reclaimable space that is greater that 70 percent. The storage pool has three volumes:

• FILEVOL1 with 65 percent reclaimable space
• FILEVOL2 with 80 percent reclaimable space
• FILEVOL3 with 95 percent reclaimable space

When reclamation begins, the server compares the percent of reclaimable space for each volume with the reclamation threshold of 70 percent. In this example, FILEVOL2 and FILEVOL3 are candidates for reclamation because their percentages of reclaimable space are greater than 70. To determine the percentage of reclaimable space for a volume, issue the QUERY VOLUME command and specify FORMAT=DETAILED. The value in the field Pct. Reclaimable Space is the percentage of reclaimable space for the volume.

Specify a value of 50 percent or greater for this parameter so that files stored on two volumes can be combined into a single target volume.

OFFSITERECLAIMLimit

Specifies the maximum number of offsite storage pool volumes that the server tries to reclaim. This parameter is valid only for copy storage pools. Limiting the number of offsite volumes can prevent the server from spending more time analyzing volumes rather than reclaiming them. You can specify a number from 0 to 99999. This parameter is optional. If not specified, the OFFSITERECLAIMLIMIT attribute of the storage pool definition is used.

Wait

Specifies whether to wait for the server to complete processing this command in the foreground. This parameter is optional. The default is No. Possible values are:

No

Specifies that the server processes this command in the background.

You can continue with other tasks while the command is being processed. Messages that are created from the background process are displayed either in the activity log or the server console, depending on where messages are logged.

To cancel a background process, use the CANCEL PROCESS command. If you cancel this process, some files might have already been moved to new volumes before the cancellation.

Yes

Specifies that the server processes this command in the foreground. The operation must complete before you can continue with other tasks. Output messages are displayed to the administrative client when the operation completes. Messages are also displayed either in the activity log or the server console, or both, depending on where the messages are logged.

Note: You cannot specify WAIT=YES from the server console.

Related commands