You may want to delete database or recovery log volumes for a number of reasons. For example:
When you delete a database or recovery log volume, TSM tries to move data from the volume being deleted to other physical volumes in the database or recovery log.
To delete space, perform the following steps:
To determine if volumes can be deleted from the database or recovery log, check the volume sizes and the amount of unused space. To check the sizes of the volumes in the database, enter:
query dbvolume format=detailed
The server displays the following type of information:
+--------------------------------------------------------------------------------+ | | | | | | |Volume Name (Copy 1): d:\dbvol\vol4 | | Copy Status: Sync'd | |Volume Name (Copy 2): | | Copy Status: Undefined | |Volume Name (Copy 3): | | Copy Status: Undefined | |Available Space (MB): 24 | |Allocated Space (MB): 24 | | Free Space (MB): 0 | +--------------------------------------------------------------------------------+
In this example, VOL1, VOL2, VOL3, and VOL4 each have 24MB of available space, and VOL5 has 100MB. To determine if there is enough unused space to delete one or more volumes, enter:
query db
The server displays the following type of report.
+--------------------------------------------------------------------------------+ |Available Assigned Maximum Maximum Page Total Used %Util Max. | | Space Capacity Extension Reduction Size Pages Pages %Util | | (MB) (MB) (MB) (MB) (bytes) | |--------- -------- --------- --------- ------- --------- --------- ----- ----- | | 196 196 0 176 4,096 50,176 4,755 9.5 9.5 | +--------------------------------------------------------------------------------+
The Maximum Reduction field shows the assigned capacity not in use. In this example, you could reduce the database by up to 176MB. This is enough space to allow the deletion of VOL1, VOL2, VOL3, and VOL4.
If there is not enough space on the remaining volumes, allocate more space and define an additional volume, as described in Increasing the Size of the Database or Recovery Log and continue with Step 2: Reducing the Capacity of the Database or Recovery Log.
The database or recovery log capacity is reduced in 4MB increments. For example, assume that based on the utilization of the database, VOL5 alone could contain all the data. To reduce the database by the amount of available space in VOL1 through VOL4, 96MB, enter:
reduce db 96
Reducing capacity is run as a background process and can take a long time. Issue a QUERY PROCESS command to check on the status of the process.
After reducing the database by 96MB, the assigned capacity is 100MB and the maximum extension is 96MB, as shown in the following example:
+--------------------------------------------------------------------------------+ |Available Assigned Maximum Maximum Page Total Used %Util Max. | | Space Capacity Extension Reduction Size Pages Pages %Util | | (MB) (MB) (MB) (MB) (bytes) | |--------- -------- --------- --------- ------- --------- --------- ----- ----- | | 196 100 96 92 4,096 24,576 86 0.3 0.3 | +--------------------------------------------------------------------------------+
After you reduce the database or recovery log, use the smaller size for a few days. If the maximum utilization does not go over 70%, you can delete extra volumes.
Note: | You cannot delete volumes if there is not enough free space for the server to move existing data from the volume being deleted to other physical volumes in the database or recovery log. |
delete dbvolume vol1 delete dbvolume vol2 delete dbvolume vol3 delete dbvolume vol4
TSM moves data from the volumes being deleted to available space on other volumes, as shown in Figure 69.
Figure 69. Deleting Database Volumes
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After the data has been moved, these volumes are deleted from the server.