Database Software

For testing and learning purposes, I have installed OSB 10.3 and the virtual tape management system mhvtl (http://mhvtl-linux-virtual-tape-library-community-forums.966029.n3.nabble.com/MHVTL-Linux-Virtual-Tape-Library-Getting-Started-td1663811.html). It seems to work quite well apart from one serious shortcoming. If a virtual tape which is already labeled and used as part of a media family is unmounted from the drive, a subsequent re-mount leads to a relabel of the volume whereupon all pieces and any reference to the volume are lost. If the virtual tape is left in the drive, there is no issue - new backups are appended to the end of the volume as one would expect.

Somewhat perversely, when I mount a used tape, OSB correctly identifies it. As soon as I start writing to it though, the volume is re-labeled.

I can overcome the issue by using obtar -z to advance the tape to the end of the volume.

% obtar -zf VDAT72
Volume label:
Volume UUID: d4c93502-15a0-102e-b7f5-00163e319d06
Volume ID: RMAN-DENVER-000025
Volume sequence: 1
Volume set owner: root
Volume set created: Tue Feb 08 13:02:21 2011
Media family: RMAN-DENVER
Volume set expires: never; content manages reuse
Original UUID: d4c93502-15a0-102e-b7f5-00163e319d06

Archive label:
File number: 4
File section: 1
Owner: root
Client host: node1
Backup level: 0
S/w compression: no
Archive created: Tue Feb 08 13:09:26 2011
Backup piece name: c-3970187662-20110208-03
Backup db name: denver
Backup db id: 3970187662
Backup copy number: not applicable
Backup content: autobackup

$ obtar -zf VDAT72
Error: no backup image at current position -- end of volume set.

At this point, any new backup starts writing to the virtual tape at the current position, and existing files on the volume are preserved - no re-label is carried out.

I'd like to debug OSB but when I try to set up debugging on the volume, I get:

$ obtool labelvol obtaropt J drive VDAT72
Error: Label/reuse operation requires that you specify no names or BDFs.

If anyone has some clues, I would be grateful.

Edited by: Graeme Lawton on Feb 8, 2011 2:12 PM

Edited by: Graeme Lawton on Feb 8, 2011 2:13 PM