In a Linux server it was not showing the tape drives available that were previously available.
On /var/log/messages was showing a message about a reservation conflict
Nov 29 00:49:15 linux kernel: st 3:0:19:0: reservation conflict
This message is about the SCSI reservation that the backup software is applying to the tape drives.
Once the software finishes using the tapes it will make them available to other servers
setaOffice 