Hi,

Tar stores by default both user/group name and numeric information when 
creating an archive.
When creating archives, if --numeric-owner is used, the user/group name 
information isn't stored.
When restoring, if --numeric-owner is set, tar will only use the numeric 
information from the archive and disregard the names.
So you probably want to use --numeric-owner option only to restore.

I have done several bare metal restores with Knoppix and tar without problems.

See https://www.redhat.com/archives/fedora-list/2004-May/msg01985.html

--
Inaki Sanchez


Frank Smith wrote:

Jon LaBadie wrote:

On Mon, Jan 30, 2006 at 10:00:45PM +0100, Kosa Attila wrote:

Hi all,

Environment:
- server
        - Debian Sarge, amanda-server 2.4.4p3-3;
- client
        - Debian Sarge, amanda-client 2.4.4p3-3;
        - Debian Woody, amanda-client 2.4.4p3-3 (I made it myself
          backport).

The clients' full backup is succesful with the following config
(typically reiserfs partitions are required to backup):

...

I tried to restore the full backup by 3.7 Knoppix CD, and I
succeeded, but there is only one mistake. Uid/gid pairs in the
Knoppix system are different than in my Woody (or Sarge) system,
therefore certain parts of the restored system are not able to
work. I think it would be a solution if the tar used also a
--numeric-owner option to backup. I wonder if the only
possibility to do it is rewriting the source or there is any
simpler method I didn't notice.

I love it when man pages don't describe all the options and you
have to go to "info" to see what the poster is talking about :(

If the users do not have the same numeric id's on both systems,
how would telling tar to use numeric id's help your situation?

I recall having this issue restoring on the Amanda server where
the client machine user had a different UID on the server, and
somehow after tarring up the temp restore directory on the server,
and rsyncing it back to the client, the files ended up with a
different uid than how they originally were on the client.
   I suspect Amanda's invocation of tar doesn't use --numeric-owner,
 so if bob is UID 1000 on machine A and UID 2000 on machine B, and
you backup bob's files on A and restore on B, then move them back
to A, they end up owned by 2000 on A, which is not bob on A.
   Or possibly I screwed up somewhere and wasn't aware of it. I just
'chmod -R' the directory and didn't investigate it further at the
time.

Frank