TAR between two different HP systems

[JORGE SANCHEZ_1]

I have some tar tapes made on an HP-UX 10.20 system, I am trying to read them in a system with HP-UX 11.00 but I am getting the "directory checksum error" on some of them, do you know if there is a compatibility problem?

Do you have a link for download a tar GNU version for HP-UX?

Thank you

[Ivan Ferreira]

And if you list the tape on the 10.20 system you don't have the "directory checksum error"?

You can also try:

11-00-system> rsh 10-20-sytem tar cvf - / | tar tvf -

[Steven Schweda]

> I have some tar tapes made on an HP-UX
> 10.20 system,

Using HP's "tar", or GNU "tar", or what?

> I am trying to read them in a system with
> HP-UX 11.00

With HP's "tar", or what?

So why ask in a Linux forum, instead of an
HP-UX forum?

> do you know if there is a compatibility
> problem?

Between what and what?

> Do you have a link for download a tar GNU
> version for HP-UX?

Is Google not available where you are?

http://hpux.cs.utah.edu/hppd/hpux/Gnu/tar-1.19/

[Nicholas Noor_1]

Either you have not created a directory to where the files go or you have no permission to the filesystems or directory or the operation. Other than the version, it should only be a minor difference.

If permissions are no the issue, then check the space on the system it may check for available space.

If this works let me know.

[Dennis Handly]

>Nicholas: you have not created a directory to where the files go or you have no permission to the filesystems or directory or the operation.

This is unrelated to "directory checksum error".

>Other than the version, it should only be a minor difference.

Right, they should be compatible.

>then check the space on the system it may check for available space.

Again, unrelated to Jorge's error.

[OldSchool]

A) "directory checksum" errors should not occur between hp-ux "tar" when moving between 10.20 and 11.0. The versions are compatible

2) Generally it indicates that the version of "tar" being used can't read the file. the tape could be corrupt, not contain tar data, contain data written by GNU tar w/ incompatible options settings or many other things, including drive compatibility issues

[TwoProc]

I'm just guessing, but since you said the tape s were made on a 10.20 system... are these tapes old? They are only good for about 5 years, and after that they start getting a bit iffy. 10.20 tapes could easily be 10 years old...

If you're not fooling with old tapes, then ignore comments below...

In the case of old tapes:
At times, you can try cleaning the tape heads and retrying the re-reading the tape. As a last ditch effort to save the contents from an old tape... you can stick it in an oven for about 30 minutes with the oven set as low as it can go. Now, I've not tried this on dds tapes, but many thousands of moons ago, it worked well enough for 9 track tapes, giving you ONE LAST read of a tape, some of the time. The idea was to take the moisture out of the tape that it has accumulated over the years. If your ovens' lowest temp makes tape cases "warp", then after bringing up the oven to lowest heat, turn it off, wait 10 minutes, and try with another tape. Of course, this works best when trying to save a batch of tapes (like I was), and you *know* you're not going to get them all, but you're looking to save all you can. Make sure that in your "last read of all time", you're actually storing the contents of the whole tape somewhere so that it can be recreated on new media, if desired. Also, be prepared to clean and reclean that tape head often, before, during and especially after each process. A "cleaning tape" alone probably won't cut it, you'll probably have to clean with tape head cleaning solution and cleaning swabs, if you don't have this handy, I've sucessfully used "pure" ethyl alcohol (u can get this from pharmacist at nearby drug store).

[Bill Hassell]

If the checksum error is not accompanied by an I/O error message (errno 5), this usually means that it was not a tar backup or the block size on the tape is not as expected. HP's tar (the industry standard version) is particularly braindead in that it can create a different block size (-b) but has difficulty in determining the block size when reading a tape. Probably the best tool to read a problem tape is pax. It knows tar and cpio and will automatically determine the block size for either format. Use pax -v -f /dev/rmt/whatever to list the contents.

If pax reports: This doesn't look like a tar archive, then look at the first record on the tape:

# mt -f /dev/rmt/whatever rewind
# dd if=/dev/rmt/whatever count=1 | xd -xc

If you see hex codes: 8000 4953 4c31 3020 (which has the text: ISL10, then the tape is an Ignite backup tape. If instead you see: ANSI standard label ... then the tape is in fbackup format.