[OpenAFS] moving volumes

Craig_Everhart@transarc.com Craig_Everhart@transarc.com
Thu, 30 Aug 2001 09:43:28 -0400 (EDT)


Excerpts from mail: 30-Aug-01 [OpenAFS] moving volumes John
Berninger@ncsu.edu (701*)

> Is there an easy, harmless way of moving volumes between cells w/o
> losing data?  I'm told that a Thing That Can't Be Done in AFS...

> I'd really rather not create a new volume then schlep the data through a
> tar pipe, if at all possible...

Think about it: you're crossing authentication domains, so
owner/group/ACL information would in principle all mean something new,
and should be translated.  Also, you're not likely to get one cell's
VLDB to point to a volume in another cell, so at most you're copying and
pasting the volume into a new cell, not moving in the "vos move" sense
where all old clients would just find the data there.  (There is the
"linked cell" stuff that supports this to some extent and the AFS/DFS
migration tool that did the translation, but it's code to be written.)

You're likely going to have to vos dump/vos restore, so that the data
flows through a client as well as through the two volservers, unless you
can add the source volserver's authentication context (controlled by its
AFS server key) to be added to the SUsers list of the target volserver
machine.

That's a sketch of the difficulty, as far as I can tell.  If owners and
groups mean the same thing in the two cells, then "vos dump"|"vos
restore" will work.  Otherwise, it will put the old numeric principal
("user") and group IDs into the target cell authentication context,
where they might mean radically different things.

		Craig