About configuring multiple copies
To create multiple copies, the following criteria must be met:
The backup destinations must share the same media server with sufficient resources available for each copy.
The storage units that are used for multiple copies must be configured to allow a sufficient number of concurrent jobs to support the concurrent copies. The pertinent storage unit settings are and Maximum concurrent write drives.
Multiple copy operations do not support the following:
Storage units that use a QIC (quarter-inch cartridge) drive type
Storage lifecycle policies
Storage lifecycle policies offer their own method to create multiple copies.
See About writing multiple copies using a storage lifecycle policy.