EDGINERS provides a way to direct to an automated tape library the WTOR messages and MSGDISP requests to the operator and drive to get a volume mounted and demounted. These messages are issued through the library automation communication services component of OAM. If a mount on an automated tape library drive fails, DFSMSrmm uses the return and reason codes set by the library automation communication services component to test if a volume should be skipped.

During demount processing, DFSMSrmm ensures that errors detected on volumes mounted in an automated tape library are reflected in the TCDB. For example, DFSMSrmm ensures the TCDB contains information about write-protected, wrong volume, and wrong label type errors. DFSMSrmm skips the volume rather than having the operator correct the error.