A scratch pool is an optional volume pool that you can use to ensure that volumes are allocated to the volume pools that need them. Media Manager moves volumes from a scratch pool to other pools that do not have volumes available, including Vault pools. Expired volumes are returned to the scratch pool automatically.
You can set up a scratch pool in two ways, as follows:
Create a scratch pool and add all your volumes to it. Then create all the other volume pools but do not allocate any volumes to them. Media Manager then moves volumes from the scratch pool to the other volume pools as needed and returns the expired volumes to the scratch pool.
Create your volume pools and allocate volumes to them. Then create a scratch pool and allocate volumes to it. Media Manager moves volumes between the scratch pool and the other volume pools as needed and returns the expired volumes to the scratch pool. This method may be the best option if you decide to add a scratch pool to an existing NetBackup configuration.
The scratch pool feature can affect reports for media coming on site. If you use a scratch pool, the Picking List for Vault, the Offsite Inventory, and the All Media Inventory reports may include volumes from other profiles or vaults that have expired and moved back into the scratch pool even though the reports may be for a specific Vault profile or session.