Hi,

A few days ago we completely reinstalled a server with a tape drive on
and now the darn tape refuses to make backups anymore.

The driver is compiled into the kernel, and all checks run fine:

# mt -f /dev/nst0 status
SCSI 2 tape drive:
File number=0, block number=0, partition=0.
Tape block size 0 bytes. Density code 0x41 (DLT 40GB).
Soft error count since last status=0
General status bits on (41010000):
BOT ONLINE IM_REP_EN

But if I want to put some dirs on tape with tar, I get this error:
# tar cvf /dev/st0 /some/dir
tar: Removing leading `/' from member names
tar: /dev/st0: Cannot write: Input/output error
tar: Error is not recoverable: exiting now

Does anyone knows what might cause this?

Maybe the fact that udev is used now (but I think we used it before when
we upgraded the kernel)?

I'll also see if we can extract something from a tape...

Thanks,

Wimmy

--
+----------+
| PLEASE |
| DO NOT |
| FEED THE |
| TROLLS |
+----------+
| |
| |
.\|.||/..

do you have the '-' in front of the 'c' option?
-Walt

Wim Cossement <wcosseme@nospam.bcol.be> wrote:
> Hi,
>
> A few days ago we completely reinstalled a server with a tape drive on
> and now the darn tape refuses to make backups anymore.
>
> The driver is compiled into the kernel, and all checks run fine:
>
> # mt -f /dev/nst0 status
> SCSI 2 tape drive:
> File number=0, block number=0, partition=0.
> Tape block size 0 bytes. Density code 0x41 (DLT 40GB).
> Soft error count since last status=0
> General status bits on (41010000):
> BOT ONLINE IM_REP_EN
>
> But if I want to put some dirs on tape with tar, I get this error:
> # tar cvf /dev/st0 /some/dir
> tar: Removing leading `/' from member names
> tar: /dev/st0: Cannot write: Input/output error
> tar: Error is not recoverable: exiting now
>
> Does anyone knows what might cause this?
>
> Maybe the fact that udev is used now (but I think we used it before when
> we upgraded the kernel)?
>
> I'll also see if we can extract something from a tape...
>
> Thanks,
>
> Wimmy
>

--
-
Please email innkeepATncDOTrrDOTcom if interested or in need of assistance!

> do you have the '-' in front of the 'c' option?
> -Walt

That should not make any difference, but I have...

Wimmy

So I can still get files back that are on tape, but I cant write any new
tapes (and no, the write protection is off)...

The file permissions look OK:

crw-rw---- 1 root tape 9, 0 Jun 22 09:02 /dev/st0
crw-rw---- 1 root tape 9, 128 Jun 22 09:02 /dev/nst0
lrwxrwxrwx 1 root root 9 Jun 22 09:02 /dev/tape -> /dev/nst0

So what could be wrong?

Wimmy

by 'any new tapes' do you mean write entire new volume
or diff additions to existing?
Sorry for stating the obvious but I want to rule out
you have tried to create 'a new tape'.
-Walt

Wim Cossement <wcosseme@nospam.bcol.be> wrote:
> So I can still get files back that are on tape, but I cant write any new
> tapes (and no, the write protection is off)...
>
> The file permissions look OK:
>
> crw-rw---- 1 root tape 9, 0 Jun 22 09:02 /dev/st0
> crw-rw---- 1 root tape 9, 128 Jun 22 09:02 /dev/nst0
> lrwxrwxrwx 1 root root 9 Jun 22 09:02 /dev/tape -> /dev/nst0
>
> So what could be wrong?
>
> Wimmy

--
-
Please email innkeepATncDOTrrDOTcom if interested or in need of assistance!

> by 'any new tapes' do you mean write entire new volume
> or diff additions to existing?
> Sorry for stating the obvious but I want to rule out
> you have tried to create 'a new tape'.
> -Walt

I used a brand new tape, so I just used

mt rewind
tar -cvvf /dev/nst0 /some/dir > log.txr 2> error.txt

as a test.

Wim

any clues in the pipe error.txt?
I would think if a write fails something should be there.
Even a bad tape or dirty head would leave something.
-Walt

> mt rewind
> tar -cvvf /dev/nst0 /some/dir > log.txr 2> error.txt
>

if the only error output is
"tar: /dev/st0: Cannot write: Input/output error"
I personally would try some more isolation tactic like
additional tapes or drives. (of a known state)
Forgive me for pointing to obvious stuff but its real
easy to get something on the head or tape.
And I personally would want to rule out all hardware
before thinking some software problem cropped up.
If the drive is external perhaps attach it elsewhere as
a proof?
again don't shoot the messenger
I'm expermenting with using rsync on a disk space as
I'm getting tired of my drives floating in and out of
ability.

-Walt

> mt rewind
> tar -cvvf /dev/nst0 /some/dir > log.txr 2> error.txt
>
> as a test.
>
> Wim

Well, someone told me dmesg gives some info (I was kinda wondering how
some people could possibly get those kernel messages during bootin ;-)

And it gives me this:

st0: Error with sense data: <6>st0: Current: sense key=0xb
ASC=0x47 ASCQ=0x0
Info fld=0x2800

Anywhere I can look what those codes mean?
That same person suggested the kernel sources, so I'll take a looksee there.

And I'm gonna put it on another machine to test as well.

Wimmy

PenguinsAnonymous@notAchance.org wrote:

> if the only error output is
> "tar: /dev/st0: Cannot write: Input/output error"
> I personally would try some more isolation tactic like
> additional tapes or drives. (of a known state)
> Forgive me for pointing to obvious stuff but its real
> easy to get something on the head or tape.
> And I personally would want to rule out all hardware
> before thinking some software problem cropped up.
> If the drive is external perhaps attach it elsewhere as
> a proof?
> again don't shoot the messenger
> I'm expermenting with using rsync on a disk space as
> I'm getting tired of my drives floating in and out of
> ability.
>
> -Walt /..

So anyway, it was like, 15:56 CEST Jun 23 2005, you know? Oh, and, yeah,
Wim Cossement was all like, "Dude,

> st0: Error with sense data: <6>st0: Current: sense key=0xb
> ASC=0x47 ASCQ=0x0
> Info fld=0x2800

Checked your cables and proper termination of the chain lately?
If that's not an expected message (unhandled timeouts from EOT or
whatever), I'd start looking into potential hardware problems.

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