CBR4172I Mount for volume volser in library library-name cancelled.
Explanation
The mount request for volume volser in library library-name was canceled at the library. Prior to the mount request being canceled, an operator at the library manager console indicated that the library was to be taken offline. In order for the library to be taken offline, pending operations must either be completed or canceled. If a state exists at the library that prevents an operation from completing, that operation is canceled in order for the library to be taken offline.
System action
The LACS request fails with a permanent error return code. Messages issued by the caller of LACS are written concurrently with this message.
System programmer response
Resubmit the failing job after the library is brought back online.
Source
Object Access Method (OAM)