I have one old PowerVault 110T drive with bunch of tapes for my personal backups and its working fine. On a local ebay-like site I saw a PowerValut 122t VS80 for a very nice price. I thought it will be good to upgrade my actual drive. And as a bonus I will have something to read the tapes if the 110 would die...
When the 122t arrived I tested it and it works nicely with the tapes that came with it. However it does not load tapes written by 110T. Both drives use DLT-IV tapes and the tapes are actually very similiar (same vendor, and you would not distinguish them apart but for serial number and label). I found a document called "Dell™ PowerVault™ DLT, VS, and SDLT Media Handbook Version 2.0" stating:
Reusing Type IV Media Formatted by DLT7000 or DLT8000 in VS80/DLT1
Drives Type IV media previously recorded by a DLT7000 or DLT8000 are not read compatible with DLT 4000, DLT1, or VS80 drives.
I do not have to mention that 110T uses DLT7000 tape format :-) But yeah, I can not read tapes from the other drive but at least I would like to use the tapes in the new drive. The mentioned document says:
Type IV media originally formatted in DLT7000 and DLT8000 drives can be used in a VS80/DLT1 drive only if the media is first set to hardware compression level 20 GB and erased in the DLT7000/8000 drive. Otherwise the media will be automatically ejected from the DLT1 and VS80 drive.
I tried that and the 122T now loads the tape but reports it as Write Protected and I am not able to do anything with the tape. I found out topic on dell forum with exactly the same problem http://en.community.dell.com/support-forums/storage/f/1216/p/13703404/13826390.aspx#13826390 and basically they say, that there is no way how to reuse the tapes. But the post is rather old so I was hoping if anyone here would know something more... At least some way how to force the 122T drive to format/erase the tape...
For the sake of completness, some more details: I am using Linux (Fedora 17), Adaptec SCSI controller (not sure about the model) and I am using the basic "mt","mtx" and "dd" commands. The tape that came with the drive work exactly as expected, the old ones differs only that "mt status" reports "WR_PROT" and every attempt to do write operation ends up with "read-only filesystem". If I get this to work I will connect it to my bacula instalation but now I am testing on a plain system with the low-level commands....
