Problem with tape drive: illegal seek

Problem with tape drive: illegal seek

[Christian Iversen]

Whenever I use --verify for tar, I get problems. Specifically, I get 
"Illegal seek" when tar gets to the verify phase. 

I'm trying this on a Compaq SDT-10000 on an Adaptec AHA-3940U2x/395U2x, 
according to lspci.


The following simulates my backup script.. to some extend :)

[root@boreas]/tmp #dd if=/dev/urandom of=random-data bs=1024 count=1024                        
1024+0 records in
1024+0 records out
1048576 bytes transferred in 0,324788 seconds (3228493 bytes/sec)
[root@boreas]/tmp #mt rewind
[root@boreas]/tmp #tar --create --verify --file /dev/tape random-data
tar: /dev/tape: Warning: Cannot seek: Illegal seek
[root@boreas]/tmp #dmesg | tail
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
ReiserFS: md0: warning: vs-8115: get_num_ver: not directory item
[root@boreas]/tmp #

Should I look into the buggy'dness of this, or am I doing something wrong?

Please note that I can restore the data just fine, if I use tar. If I try to 
use dd, I get strange errors as well:

[root@boreas]/tmp #dd if=/dev/tape of=dump
dd: reading `/dev/tape': Cannot allocate memory
0+0 records in
0+0 records out
0 bytes transferred in 3,699040 seconds (0 bytes/sec)

I hope you can help me.

-- 
Regards,
Christian Iversen

RE: Problem with tape drive: illegal seek

[Guy]

Your dd issue may be related to block size.
Tar defaults to 10k blocks, dd defaults to 512 bytes blocks.

Try this dd command:
dd if=/dev/tape of=dump bs=10k

No idea about the verify.

Guy

-----Original Message-----
From: linux-scsi-owner@vger.kernel.org
[mailto:linux-scsi-owner@vger.kernel.org] On Behalf Of Christian Iversen
Sent: Friday, February 25, 2005 6:16 PM
To: linux-scsi
Subject: Problem with tape drive: illegal seek


Whenever I use --verify for tar, I get problems. Specifically, I get 
"Illegal seek" when tar gets to the verify phase. 

I'm trying this on a Compaq SDT-10000 on an Adaptec AHA-3940U2x/395U2x, 
according to lspci.


The following simulates my backup script.. to some extend :)

[root@boreas]/tmp #dd if=/dev/urandom of=random-data bs=1024 count=1024

1024+0 records in
1024+0 records out
1048576 bytes transferred in 0,324788 seconds (3228493 bytes/sec)
[root@boreas]/tmp #mt rewind
[root@boreas]/tmp #tar --create --verify --file /dev/tape random-data
tar: /dev/tape: Warning: Cannot seek: Illegal seek
[root@boreas]/tmp #dmesg | tail
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
program smartd is using a deprecated SCSI ioctl, please convert it to SG_IO
ReiserFS: md0: warning: vs-8115: get_num_ver: not directory item
[root@boreas]/tmp #

Should I look into the buggy'dness of this, or am I doing something wrong?

Please note that I can restore the data just fine, if I use tar. If I try to

use dd, I get strange errors as well:

[root@boreas]/tmp #dd if=/dev/tape of=dump
dd: reading `/dev/tape': Cannot allocate memory
0+0 records in
0+0 records out
0 bytes transferred in 3,699040 seconds (0 bytes/sec)

I hope you can help me.

-- 
Regards,
Christian Iversen
-
To unsubscribe from this list: send the line "unsubscribe linux-scsi" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Re: Problem with tape drive: illegal seek

[Kai Makisara]

On Sat, 26 Feb 2005, Christian Iversen wrote:

> 
> Whenever I use --verify for tar, I get problems. Specifically, I get 
> "Illegal seek" when tar gets to the verify phase. 
> 
I looked at tar 1.13.25 sources and this looks like a tar bug: verify from 
tape does not work for the first file (and I am not sure about other 
files). After writing, tar tries to skip backwards over two filemarks. 
When writing the first file, there is no second filemark to skip over: 
this fails and gives you the error. If you do verify with a second call to 
tar (tar --compare) after skipping backwards with mt, this should work.

...
> Please note that I can restore the data just fine, if I use tar. If I try to 
> use dd, I get strange errors as well:
> 
> [root@boreas]/tmp #dd if=/dev/tape of=dump
> dd: reading `/dev/tape': Cannot allocate memory
> 0+0 records in
> 0+0 records out
> 0 bytes transferred in 3,699040 seconds (0 bytes/sec)
> 
Guy already solved this problem. The message (Cannot allocate memory) is 
not very clear but this is what other Unices use.

-- 
Kai

Re: Problem with tape drive: illegal seek

[Christian Iversen]

Thanks to you both!

Indeed, "dd" works when bs=10k, and tar works as long as you don't try to 
auto-compare it. I'll look into using --compare instead, thanks. 

I wonder if this is a bug or feature in tar? Should I report it?

-- 
Regards,
Christian Iversen