Before a backup can be performed, the device must be defined explicitly as either a transaction volume or a backup volume. A device may remain unassigned indefinitely but will not be available for use in any backup until its operation type has been defined.
A device may also be defined as both a replication source device and a transaction volume but cannot be both a replication device and a backup volume.
The backup volume must be the same size (that is, the same number of bytes) as the transaction volume.
