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Best practices for IBM Spectrum Protect storage pool conversion

Technote (FAQ)


What best practices and guidelines are recommended for storage pool conversion?


You must plan and prepare for storage pool conversion, especially if the conversion of a primary storage pool that uses a FILE device class that reuses the existing disk.


Each section below covers the best practices, lessons learned and general guidance for each type of storage pool that can be converted.

General Recommendations:

For more information about the REPAIR OCCUPANCY command, see
  • You can complete conversion processing while the target container storage pool processes data. Ensure that you have enough system memory to manage the conversion process.
  • If the storage pool conversion completes, but the status of the pool states "Conversion Stopped", issue the QUERY CONTENT command and specify FOLLOWLINKS=YES to display all files, including files that are stored on the volume and any files that have links to the volume.

If no files are displayed when you issue the QUERY CONTENT command, issue the
DELETE VOLUME command and specify DISCARDDATA=YES parameter to delete all
files that are stored in the volume. If content is displayed, check to see if damage was
reported by issuing the QUERY CLEANUP command.

If damage is reported, follow these instructions:

Storage pool with a FILE device class

  • If the conversion reuses the existing disk, commonly called in-place, the target storage pool should be approximately 50% larger than the source storage pool. If there is less than 50% of free disk space in the target storage pool, you must monitor the conversion closely to track any issues related to space consumption. In particular, specify a shorter process duration and more frequent reclamation processing for the conversion process.
  • For in-place conversions,specify a shorter conversion duration to determine the behavior and draw-down speeds of the source storage pool. The frequency and the number of reclamation processes will dictate the draw-down rate rate of the source storage pool storage consumption.
  • During the conversion process, issue the QUERY CLEANUP command to identify any damaged files. You might need to repair or delete the damaged data before the conversion process ends because the source volumes that contain the damaged data are not converted until the damage is resolved.

Storage pool with a TAPE device class
  • Do not use all of the available tape drives for storage pool conversion. Reserve a few drives for database backup, reclamation, and client restore operations.
  • The number of tape devices that are required for a conversion process on total number of drives in the library. Use at least 6 tape drives to optimize the conversion process. If you use less than 6 tape drives, converting tape to a container storage pool could take several weeks dependent on total amount of data to be converted.

Storage pool with a VTL device class
No special notes at this time. Follow the guidance that is outlined in General Recommendations.

Product Alias/Synonym


Document information

More support for: IBM Spectrum Protect

Software version: 7.1.3, 7.1.4, 7.1.5, 7.1.7

Operating system(s): Platform Independent

Software edition: Enterprise

Reference #: 1993088

Modified date: 02 January 2018