Changing the storage hierarchy to resolve data storage problems

The storage hierarchy includes the defined storage pools and the relationships between the storage pools on the server.

The storage pool definitions are also used by the storage agent. If attributes of a storage pool were changed, the change might affect data store and retrieve operations. Review any changes to the storage hierarchy and storage pool definitions. Issue the QUERY ACTLOG command to see the history of commands or changes that might affect storage pools. Also, use the following QUERY commands to determine if any changes were made:

QUERY STGPOOL F=D
Review the storage pool settings. If a storage pool is UNAVAILABLE, then data in that storage pool cannot be accessed. If a storage pool is READONLY, then data cannot be written to that pool. If either situation is the case, review why these values were set and consider issuing the UPDATE STGPOOL command to set the pool to READWRITE. Another consideration is to review the number of scratch volumes that are available for a sequential media storage pool.
QUERY DEVCLASS F=D
The storage pools can be influenced by changes to device classes. Review the device class settings for the storage pools, including checking the library, drive, and path definitions. Issue the QUERY LIBRARY, QUERY DRIVE, and QUERY PATH commands for sequential media storage pools.