DLT7000 Failing to unload

[Scott D. Allen]

I have a backup routine running on a Quantum DLT7000 autochanger. The unload operation at the end of the routine is failing intermittently. Today it failed with the following error message.

ERROR: 0x0 No Sense : 0x0 No additional sense information

The command issued was

mc -p /dev/picker -sD1 -dS1

and the mc -p /dev/picker -r DS shows that SLOT 1 is EMPTY and DRIVE 1 is FULL. I was manually able to issue the command this morning, but it failed during the backup. Is this possibly caused by a process still holding onto the drive. Should I add a delay in front of the mc command? Suggestions?

--Scott

[Joseph T. Wyckoff]

Within Omniback we have implemented delays and retries because some libraries and drives are not as fast as we would hope.

I suspect you would do well to delay or add some more logic to your script as well.

Good Luck.

[Dave Wherry]

Not in an HP environment, but, in another shop I saw this behavior. As a backup grew and we were using more of the tape, it took longer to rewind. Just as you suggested we added a "sleep 90" before any tape movement functions and the problem went away.
The sleep doesn't cost you anything so I'd give it a try.

[Insu Kim]

I think that you should contact HP Hardware service and let them replace that drive.

[Lothar Krueler]

Hi,
if you are not satiesfied with inserting a delay:
what do you think about a delayed loop executing the mc command until success ? So you can log the amount of failures and time behavior related to backuptime or whatever you want and it doesn`t matter if the delay is a vew seconds to short.
Lothar

[Scott D. Allen]

Thanks to all for suggestions. I did put in the sleep command and it appears to work fine. I realize that the best (most efficient) way would be to implement a loop, but this is a pretty simple script that doesn't require that level of sophistication. Thanks again!

--Scott

[Rick Garland]

Had the same type of SENSE error as well.

The issue turned out to be the guide rails that the picker runs on was bent in. This caused the picker to become slow when it was going down to unload a tape from a drive. Did the sleep bit and that helped but we also got the rail bent back into place and we removed the sleep statement. No troubles at all.