About SPC-2 SCSI reserve on AIX
By default, NetBackup uses SPC-2 SCSI reserve and release for tape drive reservations in shared drive environments. The NetBackup Shared Storage Option provides shared drive functionality in NetBackup.
Alternatively, you can use SCSI persistent reserve for shared tape drive reservations in NetBackup, as follows:
For the tape drives that support SPC-3 Compatible Reservation Handling (CRH), you can use SCSI persistent reserve by enabling it in NetBackup. No special configuration in AIX is required.
For the tape drives that do not support CRH, you must disable SPC-2 SCSI reserve in AIX for those drives. After you disable SPC-2 SCSI reserve, you can use persistent reserve by enabling it in NetBackup. If the drive does not support CRH and you do not disable SPC-2 SCSI reserve, access attempts to the drive fail.
See Disabling SPC-2 SCSI reserve in AIX.
Warning:
If the tape driver does not let you disable SPC-2 SCSI reserve, do not use SCSI persistent reserve with the drives that do not support CRH. The sctape driver is an example of a tape driver that lets you disable SPC-2 SCSI reserve.
For more information about NetBackup and SCSI reservations, see the following:
The description of the Media host property in the NetBackup Administrator's Guide, Volume I.
The "How NetBackup reserves drives" topic in the NetBackup Administrator's Guide, Volume II.