topic Re: Backup question in Operating System - HP-UX

Backup question

Jie Li — Fri, 01 Nov 2002 15:47:18 GMT

We got the followin backup error message last night:
"cannot open /dev/rmt/0m"

I am not the guy who put/change the backup tape. He told me that he put a new tape in last night. Will this has something to do with the backup error?

Thanks

Re: Backup question

James R. Ferguson — Fri, 01 Nov 2002 15:54:44 GMT

Hi:

The "cannot open..." will be returned if there is no tape or if the tape isn't write-enabled.

Regards!

...JRF...

Re: Backup question

MANOJ SRIVASTAVA — Fri, 01 Nov 2002 16:03:51 GMT

Hi Jie

Couple of reasons :

1. Tpae not there when the command was run.
2. Tape read only but then it will give u some write prtoected error ?
3. Tape drive itslef is bad , like the sesonsr have dust etc.

Put a new tape and try to do a tar cvf /dev/rmt/0m < test file name > to check wheter the files can be written or not .

Manoj Srivastava

Re: Backup question

Richard Steven — Fri, 01 Nov 2002 21:00:36 GMT

You could try using the mt command to check if the tape drive is working:

mt -t /dev/rmt/0 rew

This should rewind the tape.

Regards

Richard :-)

Re: Backup question

Fred Martin_1 — Sat, 02 Nov 2002 12:02:02 GMT

Like the folks above, I would also assume that you had no tape in, or a write-protected tape, or a bad tape. That seems most likely.

Especially if it works today, or most days.

If that's not it though, you'll need to check the system to make sure the device is still properly set up, still has device files, etc.

If you're the sys admin, you'll probably know anyway, if something was being done to the system that -might- have accidentally messed up the tape device files.

But if you've reviewed the device, and the tapes, it may be a bad drive. I had one recently replaced (HP Support) that was giving similar errors for no reason that we could find.

Re: Backup question

Fred Martin_1 — Sat, 02 Nov 2002 12:07:39 GMT

Since we're on the subject I thought I'd add this - something we do when you have a pesky run of tape failures for no apparent reason.

We have a series of daily tapes which we rotate (we use 15).

When we have a tape failure that has no apparent cause, we just note the date on the tape box.

If we get two failures on the same tape in a month, we replace it.

It also allows us to look for patterns, i.e. always fails on Friday, etc. that might help determine the cause.