The QUSRSYS library contains three important files that are used during a save operation:
When planning to save the QUSRSYS library, you need to understand the end of volume implications when saving in a nonrestricted state. For example, if the system is unable to save all of QUSRSYS on the current tape, BRMS requests that you mount another volume. When locked, i5/OS cannot get the required QUSRSYS files ready and update them. The save fails with a message identifier of CPF37A0.
To minimize the chance of spanning QUSRSYS across multiple volumes and to create a separate control group to save QUSRSYS, save this control group before saving the *ALLUSR control groups. If you do not omit this library through the backup policy, BRMS saves it twice. These recommendations assume that you are performing the save in a restricted state and that the QUSRSYS library can fit on the mounted volume.
When performing saves using *ALLUSR, or *ALLPROD, ensure that you understand which Q libraries are saved and which are not saved. Refer to either the Backing up your system topic or the online help text for the SAVLIB command. to determine what libraries are considered user libraries. User libraries QGPL, QUSRSYS and QUSRBRM can never be saved to TSM servers.