We are receiving the following error on our z/VM platform:
VMLBAK01 FAILED. ERROR 100 FROM VMLMOUNT EXEC. TMC BACKUP IS REQUIRED.
We have been unable to locate the cause of the error, and have not been able to find from documentation what "Error 100" would indicate. The best we can find is that this is either an issue with VM:Spool, VM:Tape, or VM:Backup.
Release : 1.8
Component : CA VM:Spool
TMC Backup required.
This is likely an issue with your VM:Spool backup(s).
VMLBAK01 is a VM:Spool worker that gets defined during a spool backup operation.
VMLMOUNT is VM:Spool.
The RC=100 is the return code passed back to the VM:Spool worker from VM:Tape. VM:Tape sends RC=100 when it can't mount a tape for whatever reason.
Found that VM:Tape couldn't mount the tape because a TMC backup is required.
which means a TMC is backup *is* required.