Creating a volume pool
Ensure that the volume pools you create have sufficient volumes allocated to them (or to a scratch pool if one exists).
After a volume is assigned to an off-site volume pool, it remains in that pool and is used for rotation within that same pool. (Unless a scratch pool exists, in which case it is returned to the scratch pool).
See the NetBackup Web UI Administrator's Guide > Configuring tape media > Managing volume pools section for more information about volume pools and allocating volumes to them.