Coda File System

Re: volume cloning/backup problems

From: Jan Harkes <>
Date: Tue, 18 Jul 2000 21:22:34 -0400
On Tue, Jul 18, 2000 at 05:40:13PM -0400, Stephan Koledin wrote:
> I'm currently working with coda 5.3.8 on RedHat6.2. I'm having some
> difficulties cloning and then mounting the replicated volume as a read-only
> snapshot or backup. Not sure if I'm just missing something or what. Is this
> not currently a supported feature, or am I just doing it wrong? Here's an
> example of what I see. Basically, most of the process goes ok, but then the
> volume does not seem to mount properly.
> [root_at_machine]# volutil lock 1000002
> [root_at_machine]# volutil backup 1000002
> [root_at_machine]# cfs mkm /coda/home/backup home.user.backup
> [root_at_machine]# ls /coda/home/backup/
> ls: /coda/home/backup/: No such file or directory

The backupvolume has been created succesfully, but the volume location
database which is shared across all server has not.

Run ' [<server>]' on the SCM and the VLDB will get updated,
after that the backup volume will be found. Rerunning volutil backup
will reuse the existing volumeid, so this is a once only operation.

There also is a 'volutil dump <backupvolumeid>' command, which fetches
the dump of the backup snapshot (or an incremental dump) in one big and
more efficient transfer and writes it to stdout. That one doesn't need
an up-to-date VLDB, because it connects to the same server as the
other volutil commands. volutil has a `-h <server>' option to pull the
dumps from a remote server.

After grabbing the dump, run 'volutil markancient <backupvolumeid>' to
indicate a successful dump. Incremental dumps are made against the last
successful backup of a lower level (maybe I am mixing up the terms
incremental dump and differential dump here).

The dumpfile includes everything such as ACLs and version vectors. The
dumpfile can be restored, but recreates the readonly backup volume. So
restoring a readwrite replicated volume will still require copying the
files and ACLs around and losing the version vector information. Maybe
we'll figure out how to fully restore the dump to a rw-replica at some
point, which can then be resolved back into a fully replicated volume.

Received on 2000-07-18 21:25:16