[OT] Re: What's the best possible email failover solution

[Chuck Swiger]

Bill Moran wrote:
> Christian Laursen <xi at borderworlds.dk> wrote:
>> If you are running FreeBSD 5, you should be able to make a filesystem snapshot
>> and rsync from there.
> 
> I suppose I should have commented on that ;)
> 
> We're not running FreeBSD 5 on these production machines yet ... but it's
> likely we will be soon, so I'm considering using snapshots.
> 
> To my understanding, we still have to stop Cyrus while the snapshot is
> being created (to ensure consistency) but since a snapshot takes a lot
> less time than an rsync, this should be a big improvement.  Once the
> snapshot is created, rsync can take as long as necessary.

No, snapshots can be taken without significantly interrupting running 
processes, although I'm not sure how long filesystem access gets blocked while 
creating the snapshot.  You could also detach a RAID-1 mirror of the data 
(using vinum, ccd, whatever) and backup that, and then re-attach and resync 
the mirror drive to the live volume.

Both of these methods make taking a very current backup easy; they do not 
provide live replication of the data, however.

-- 
-Chuck