Backup Fails

[Kranti Mahmud]

Hi,

I hav a DL 380 G4 with a DAT72 tape drive at 5300 Tape Array. The OS is RHEL-4. When I'm trying to take tar backup, I found the following erros:

[root@gpklvs2 /]# uname -a
Linux gpklvs2.grameenphone.net 2.6.9-42.0.2.ELsmp #1 SMP Thu Aug 17 18:00:32 EDT 2006 i686 i686 i386 GNU/Linux

[root@gpklvs2 /]# dmesg | grep tape
Attached scsi tape st0 at scsi1, channel 0, id 5, lun 0

[root@gpklvs2 /]# cd /home
[root@gpklvs2 home]# ll
total 40
drwxr-xr-x 2 root root 4096 Apr 4 2007 cluster
drwxr-xr-x 2 root root 4096 Jul 26 2006 diwakar
drwxr-xr-x 3 root root 4096 Jul 24 2006 kvsms-patch
drwx------ 2 root root 16384 Mar 9 2006 lost+found
drwxr-xr-x 2 root root 4096 Apr 16 2006 netbackup
drwxrwxrwx 4 root root 4096 Oct 20 2008 tanvir
drwxr-xr-x 2 root root 4096 May 20 11:36 testbackup

[root@gpklvs2 home]# tar -czf /dev/st0 /home/testbackup
tar: Removing leading `/' from member names
tar: /dev/st0: Cannot open: Input/output error
tar: Error is not recoverable: exiting now
tar: Child returned status 2
tar: Error exit delayed from previous errors

[root@gpklvs2 home]# tar -tzf /dev/st0
tar: /dev/st0: Cannot open: Input/output error
tar: Error is not recoverable: exiting now
gzip: stdin: unexpected end of file
tar: Child returned status 2
tar: Error exit delayed from previous errors

[root@gpklvs2 home]# mt -f /dev/st0 status
SCSI 2 tape drive:
File number=-1, block number=-1, partition=0.
Tape block size 0 bytes. Density code 0x0 (default).
Soft error count since last status=0
General status bits on (50000):
DR_OPEN IM_REP_EN

Any suggestion from anyone?

Rgds-Kranti

[Steven E. Protter]

Shalom,

Open the hardware browser and see if the tape drive is detected.

Do a test read from a tape, you know has a valid archive on it.

Probably the tape drive is not detected or configured properly.

You may need drivers, but based on what I see the drive is much older than the OS. It could be a conflicting SCSI configuration or connecting the drive to a SCSI card that does not support the tape drive.

SEP

[Kranti Mahmud]

Hi SEP,

Great to got a repsonse from a BOSS like U.

BTW,

Open the hardware browser and see if the tape drive is detected.
=> The tape is detected perfectly from the OS.

Do a test read from a tape, you know has a valid archive on it.
=> Please clarify this point.

Probably the tape drive is not detected or configured properly.
=> The tape drive is configured @ 2007, and the customers taking backup perfectly.
This problem occurs abt 2 weeks ago.


Is it a HW issue or Driver issue?
Is there any other way to check the root cause of the backup failure?

Rgds-Kranti

[Nido]

Hi Kranti,

If you look at the error while listing the tape acrhive it says "gzip: stdin: unexpected end of file" which means something was written on the tape.

Quick way to check the tape read/write capability is to use another tape.

If you still get the errors, I would have question:
Is my tape drive require some kinda cleaning :-) ?? or need to place a Hardware call.

Its been while I've used tar and mt commands, please check the options for mt man page like: going to the end of tape data...

Let me know your findings.

Good Luck!!

[Kranti Mahmud]

Hi Nido,

Quick way to check the tape read/write capability is to use another tape.
=> I do check by using a fresh tape, but the error remains same.

If you still get the errors, I would have question:
Is my tape drive require some kinda cleaning :-) ?? or need to place a Hardware call.
==> I do clean the tape drive by a fresh cleaning cartridge, but nothing to be happy.

Its been while I've used tar and mt commands,
=>
# mt -f /dev/st0 status
SCSI 2 tape drive:
File number=-1, block number=-1, partition=0.
Tape block size 0 bytes. Density code 0x0 (default).
Soft error count since last status=0
General status bits on (50000):
DR_OPEN IM_REP_EN

# tar -tzf /dev/st0
tar: /dev/st0: Cannot open: Input/output error
tar: Error is not recoverable: exiting now

gzip: stdin: unexpected end of file
tar: Child returned status 2
tar: Error exit delayed from previous errors

Rgds-Kranti

[Nido]

Hello Kranti,

Is your tape drive writing at all?
Please use the following command on couple of smaller size files ( enable verbose mode):


tar -cvf /dev/st0

Good Luck!!!

[Kranti Mahmud]

Hi Nido,

# cd /home/testbackup/
[root@gpklvs2 testbackup]# ll
total 8
-rw-r--r-- 1 root root 1307 Apr 27 2006 hosts
-rw-r--r-- 1 root root 19 May 20 11:36 test
[root@gpklvs2 testbackup]# more test
test of tape drive

# tar -cvf /dev/st0 /home/testbackup/
tar: Removing leading `/' from member names
tar: /dev/st0: Cannot open: Input/output error
tar: Error is not recoverable: exiting now
tar: Child returned status 2
tar: Error exit delayed from previous errors

Rgds-Kranti

[Nuwan Alwis]

Hi Kranti,
You can use dd to verify if this is a problem with your tape drive.

mt -f /dev/st0 erase
mt -f /dev/st0 rewind
dd if=/dev/st0 of=/dev/null bs=1024k

if this also does not works. It might be a problem with your tape drive.

Good Luck...!

[Jeeshan]

Have you tried using a cleaning tape? Changing scsi cables does it solved? did you check the character device of tape drive's device permissions?

If nothin goes fine with you, then certainly its a tape drive or the scsi controller issue.

[Rob Leadbeater]

Hi,

Going back to your original post, you say that the tape drive is connected to a 5300 Tape Array. I assume you mean a SmartArray controller of some form.

Whilst this can work, it is not recommended to connect a tape drive to a SmartArray controller. A standard SCSI controller would be much better.

That said, you may get some hints as to what is wrong from the output of "file /dev/st0".

And I know you've said that you've tried "fresh" cleaning tapes and data tapes, but did you take them out of the packaging yourself ? In my experience, cleaning tapes are rarely marked when they've been used, and they do have a limited life (20 cycles if memory serves...)

Cheers,

Rob