[OpenAFS] Restoring ownership information of filesystem structure on /vicep*

Derek Atkins warlord@MIT.EDU
Thu, 03 Aug 2006 10:23:22 -0400

Russ Allbery <rra@stanford.edu> writes:

> Matthias Gerstner <Matthias.Gerstner@student.fh-nuernberg.de> writes:
>> I mean the structure in /vicep looks quite complex and relies on
>> features of the underlying filesystem (i.e. the inodes). That the file
>> permissions and ownership are so vital for the integrity of the AFS data
>> isn't a very beautiful approach in my opinion.

Actually, no, it does NOT use anything special from the "inode" per se.
It DOES use the Owner, Group and Mode bits (which are standard Unix
metadata).  It also uses the size (to know how big the file is).  Why
aren't you complaining about that, too?

Much of the information is encoded in the directory structure/filename
as well..  But... Some information is encoded in the owner/group/mode.

> I don't think you'll get any disagreement.  Disliking it and fixing it are
> unfortunately two different propositions.

*shrugs* I don't think it's THAT bad a solution as-is.  If you look at
the namei fs code the layout is explained in a comment.  It DOES make
a lot of sense why its done the way it is; metadata about an inode is
stored in the inode metadata, but file "name" information (FID/TAG) is
stored in the inode "name"..  Makes sense to me.

>> Besides the criticism: What is the most secure way of moving a complete
>> OpenAFS server installation (in case of only one server running) from
>> one machine to another?
> Set up the new server.  Use vos move to move the files to the new server.
> Shut down the old server.
> Alternatively, transfer the disk from the old server to the new server
> (rather than just copying files).

gnu tar with the following extra options should do what you want:
   -S -p --atime-preserve --numeric-owner

       Derek Atkins, SB '93 MIT EE, SM '95 MIT Media Laboratory
       Member, MIT Student Information Processing Board  (SIPB)
       URL: http://web.mit.edu/warlord/    PP-ASEL-IA     N1NWH
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