Once a job has successfully requested devices and volumes, intervention by the operator becomes necessary: the volumes have to be mounted on the appropriate devices.
This activity is controlled by NDM (Nucleus Device Management), which issues messages asking the operator to mount the volumes on specific devices (MOUNT messages). Each of these messages contains the VSN of the volume and the mnemonic name of the device which has already been reserved for the requesting job.
The operator can mount the volume on the specified device or on another device of the same type, or he/she may reject the MOUNT request. The user receives an appropriate message on the terminal if the command MODIFY-JOB-OPTIONS LOGGING=
*PAR(LIST=*YES) was issued for the job.