pax with -x xtar option

dmac05 · 01-08-2009, 09:07 AM

Hi,

I have changed my system Alpha ES40 HP Tru64Unix v5.1 to Sun Solaris V890 v5.10.
In my old system i used to backup and restore a 100 GB single file (an oracle logical backup (export) file ) to DDS4 tape driver (two DDS4 data cartridge) with pax tool as fallows:

Backup: pax –w –p e –v –x xtar –f /dev/tape/tape0c
restore: pax –rv –f /dev/tape/tape0c

These commands are working fine on the HPTru64Unix system to backup and restore from a DDS-4 data cartridge.
Now i need to restore these backups to my new system (Sun OS 10).
We have the same applications running on Sun and these commands are not working.

It fails and gives ‘invalid header and long file name errors”. I think its because there is no –x xtar option in pax command in Solaris

I also installed Linux Ubuntu 8.10 and Mandriva 2009 to my desktop, and tried to restore same backups from tape to disk, I got the same error shown below:

[root@localhost /]# pax -rv -f /dev/st0
/tmp/file100.dat
alldata.exp
pax: Invalid header, starting valid header search

I can backup and restore any file with pax tool(without –x xtar option) in Ubuntu and Mandriva. There is no –x xtar option in pax tool here too.

I used this for backup; pax –wvf /dev/st0 .
and for restore: pax -rvf /dev/st0
It has worked without problems.

Now I am trying to find whether -x xtar option is only Tru64Unix dependent or not. Is there a difference in HPTru64 from unix?
How can I restore backups packaged with xtar option to other unix derivatives especially Sun or Mandriva.

Regards
yakup

Agrouf · 01-08-2009, 09:52 AM

AIX doesn't recognize -x xtar either, and neither does HP-UX's pax.
On my linux machine, with my pax implementation, the following formats are recognized: cpio, bcpio, sv4cpio, sv4crc, tar and ustar.
I did not find any information about xtar, but maybe try the ustar format (extended tar format), maybe that's what they call xtar in HPTRU64 implementation?

Edit:
According to this page, xtar is ustar but with long file names and extended UID/GID values:

Quote:

xtar
Extended tar interchange format. The default blocking value for
this format for character special archive files is 10240. Blocking
values from 512 to 32,256 in increments of 512 are supported. This
option lets the user archive long file names and extended UID/GID
values.

ustar
Extended tar interchange format. This is the default output
archive format. The default blocking value for this format for
character special archive files is 10240. Blocking values from 512
to 32,256 in increments of 512 are supported.

dmac05 · 01-09-2009, 01:01 AM

Agrouf,

Thank you for the reply. But, my problem is not backup with pax tool with xtar option. I can’t restore the file backed up with xtar option to other unix derivatives.

regards yakup.