Using outboard policy management support, the library can make a second copy of a logical volume and assign it to a secondary physical volume pool. This function is supported in both the stand-alone and in the Peer-to-Peer VTS library. In a Peer-to-Peer VTS, a second copy is made in each distributed library. Because placing a second copy of a logical volume on the same physical media as the primary copy risks the integrity of the data, this support allows you to place the second copy of the logical volume on a physical volume associated with this secondary volume pool. This helps eliminate physical media as a single point of failure.

Use the library manager management class policy construct to make a second copy of a logical volume and assign it to a secondary physical volume pool. The VTS system writes the second copy of the volume to the secondary volume pool that you designate.

If you do not predefine the management class policy construct at the library and the VTS system automatically assigns default actions to the policy, the system does not perform the selective dual copy function. The default action is to make only a primary copy of the logical volume. It is not to create a second copy of the volume in the VTS. If you update the management class policy construct to make a second copy of the volume, the VTS does not make the second copy retroactively. The action of creating the second copy occurs the next time you rewind and unload the logical volume from the tape drive.