topic DDS3 tape issue....... in Operating System - HP-UX

DDS3 tape issue.......

Sean Harrodine_2 — Tue, 19 Aug 2008 08:19:06 GMT

Hi all,

I have a DDS3 tape that was written to on an L class and i'm now trying to check the tape contents on a DDS3 drive on a K460.

I've no idea what method was used to write to the tape so i have tried the following with the following results....

ioscan -fnkC tape

Class I H/W Path Driver S/W State H/W Type Description
======================================================================
tape 0 10/12/5.0.0 stape CLAIMED DEVICE HP C1537A
/dev/rmt/0m /dev/rmt/0mnb /dev/rmt/c9t0d0BESTn /dev/rmt/c9t0d0DDSb
/dev/rmt/0mb /dev/rmt/c9t0d0BEST /dev/rmt/c9t0d0BESTnb /dev/rmt/c9t0d0DDSn
/dev/rmt/0mn /dev/rmt/c9t0d0BESTb /dev/rmt/c9t0d0DDS /dev/rmt/c9t0d0DDSnb

1st attempt....

$tar -tvf /dev/rmt/0mn

Tar: blocksize = 4
directory checksum error

2nd attempt....

$frecover -r -vN -f /dev/rmt/0m

frecover(2105): did not find expected file marker
frecover(5419): checksum on volume header is incorrect.
frecover(5420): not an fbackup volume; magic value is incorrect
frecover(2105): did not find expected file marker

Can anyone give me some pointers as to what my issue may be please, and how i can extract from the tape.

Thanks in advance
Sean

Re: DDS3 tape issue.......

Steven E. Protter — Tue, 19 Aug 2008 08:58:53 GMT

Shalom,

Make sure the stape driver is compiled into the kernel.

I'm not sure there IS anything on that tape.

Its pretty clear that its not fbackup or tar files that is sure.

SEP

Re: DDS3 tape issue.......

melvyn burnard — Tue, 19 Aug 2008 09:22:33 GMT

try using pax, it should eb able to use either tar or cpio, and give you more options.

Re: DDS3 tape issue.......

Sean Harrodine_2 — Tue, 19 Aug 2008 09:56:57 GMT

Thanks for the reply.

$ pax -v -f /dev/rmt/0m|more

pax: /dev/rmt/0m : This doesn't look like a tar archive
pax: /dev/rmt/0m : Skipping to next file...

....so i suspect this tape is an ignite tape so wont contain what i require.

thanks for all assistance.

Re: DDS3 tape issue.......

Pete Randall — Tue, 19 Aug 2008 10:19:12 GMT

Whoa there, Sean. Even if this an Ignite tape, you should be able to treat it as a tar archive, you just have to skip over the boot headers before you can read it:

mt -t /dev/rmt/0mn fsf 1
tar -tvf /dev/rmt/0mn

Pete

Re: DDS3 tape issue.......

Sean Harrodine_2 — Tue, 19 Aug 2008 10:48:08 GMT

Hi Pete,

Great....just done that and it seems to be showing me everything i want, so can you confirm that i can just extract using "tar -xvf ......" as the tvf worked ????

Any thoughts on why i had to skip forward over the header ????

Is it due to the differenc in the tape drive that wrote the tape/is reading the tape ???

thanks again
Sean

Re: DDS3 tape issue.......

Pete Randall — Tue, 19 Aug 2008 10:56:09 GMT

The reason you have to skip over the header is simply that tar (or pax) does not know how to deal with it. I think, though I'm not sure I recall correctly, that it's put on the tape with dd and the format is incompatible with tar.

Pete

Re: DDS3 tape issue.......

melvyn burnard — Tue, 19 Aug 2008 11:14:16 GMT

One thought here, if you have had to skip the first area on the tape, this is probably an Ignite tape image, the first section would be the boot section, therefore frecover/pax/tar would not understand that section

Re: DDS3 tape issue.......

Rasheed Tamton — Tue, 19 Aug 2008 13:05:13 GMT

Hi,

As Melwyn said, because it is an ignite tape, the first part is the boot area of the tape. So you have to skip that part (fsf1).

After moving the file marker using mt, then you can restore any file as you would do with a normal tar archive. Just make sure that you are ok with the path of the files.

mt -t /dev/rmt/0mn fsf 1 ; tar -xvf /dev/rmt/0m path/filename

Make sure to use the no-rewind device to position the tape with mt.

filename cannot have a leading path - as far as I remmeber:

tar -xvf /dev/rmt/0m etc/lp/interface.bak

Regards.

Re: DDS3 tape issue.......

Sean Harrodine_2 — Tue, 19 Aug 2008 13:21:14 GMT

thanks to all concerned.

have found and restored the file required