When you label a volume, you associate the volume with a specific volume pool, which means that the volume is eligible to receive data when ISM needs a volume from that pool.
ism_op -label device -pool pool -volume name
If you use a file-type device, use the ISMDiskData and ISMDiskLogs pools to create file-type storage volumes.
For tape volumes, if you do not set the capacity explicitly, the ISM server uses a default setting based on the media type. ISM writes data to the tape volume, however, until the volume is full, regardless of the estimated capacity that is set.
For file-type and optical disk volumes, if you do not set a value, ISM writes data to the file-type device or optical device until the device is full. If you enter a value, however, ISM writes data to the file-type or optical disk device until that value is reached.