DAT 40 acting strangely

[Nick D'Angelo]

We recently installed a C5693A 40GB Dat drive on our R390 server, HPUX11i.

It worked fine until last week.

I can eject the tape via mt -t /dev/rmt/0m offline

However, I can not write to it using either device 0m or 0mnb.

Any ideas appreciated.

Nickd

[TwoProc]

What's the error?

[Nick D'Angelo]

fbackup(1004): session begins on Thu Jul 13 15:15:36 2006
fbackup(3047): could not open output file /dev/rmt/0mnb
fbackup(3019): would you like to enter a new output file?

This is the same error for 0m also.

[A. Clay Stephenson]

The exit status (errno) would be helpful otherwise I'll have to use "The Force" but let's go with the standard Response Center questions:

1) Is the medium write protected?
2) Is the "Need Cleaning" indicator illuminated?
3) Have you tried a different medium?
4) Have you installed the latest stape patch, PHKL_34552?

[TwoProc]

I with A. Clay for:
a) need to replace the tape
or b) need to run the tape cleaner in the head.

If neither one works, then it's time to try the patch, and then if that doesn't work, then it's time to try another tape drive in its place.

BUT, do go ahead and list /dev/rmt/0m and /dev/rmt/0mn and make sure that it is "writable" for the user that is trying to use the tape drive.

[Nick D'Angelo]

Thanks, I suspect that I will need to get the latest patch.

Nickd

[A. Clay Stephenson · Accepted solution]

One other thing that can cause a SCSI device to behave erratically is missing/poor/extra termination. Any of these conditions can cause a device to work almost perfectly -- the worst possible kind of problem. Check that the bus is terminated in exactly two places -- at the physical ends of the bus. Make certain that at least one device also supplies power for termination.

[TwoProc]

I think the patch is probably a good idea - however, it worked before without the patch...

so while I think you should go ahead and put it in, I'd be surprised to find out that it's your problem. Unless you've patched other things lately (like fbackup) and didn't catch all requirements.

[Bill Hassell]

And just a note for fbackup: you just use the 0m devicefile name. The NoRewind-Berkeley devicefile 0mnb is just extra typing. If you expect to use fbackup to append to the tape, it won't. Unlike tar and cpio, the very first action to the tape drive is an explicit rewind. Because fbackup places a complete directory at the beginning of every tape (like most commercial backup tools), the tape is always rewound to prevent appending anything as it would be undocumented (no record of the appended files)

[Nick D'Angelo]

The patch did the trick. thank you.

[A. Clay Stephenson]

-- or maybe it was simply a reboot.

[Nick D'Angelo]

the patch did the trick