You should make several operational decisions when adding devices.
For each device defined to TSM, the Device Configuration Wizard creates a storage pool, a collection of media for the device. Determine the backup device for a client's data when that client is associated with a storage pool.
Tape drive performance often depends on the way that devices are positioned in the storage hierarchy and whether the server is a stand-alone implementation or a networked implementation. A TSM server in a stand-alone implementation can go directly to tape to reduce contention for disk resources. Networked TSM servers benefit from a storage hierarchy where files are backed up to disk and migrated to tape later. See Chapter 13, "Implementing Policies for Client Data" and "Overview: The Storage Pool Hierarchy".