----- Original Message -----
From: "Manuel BERTRAND" <manuel.bertrand@xxxxxxxxxxxxxxx>
To: "CentOS mailing list" <centos@xxxxxxxxxx>
Sent: Friday, September 16, 2005 7:10 AM
Subject: Server Replication: CenOS, coda? lustre?
> Hi list,
> our lab is divided in two sites and we would like to have a clone of the
> mail server on the second site for redundancy only (used in case of a lost
> of connectivity with the primary mail server, with the MX entries in the
> DNS the clone will receive the mails instead). The problem(s) comes with
> the mail partition who must be replicated and synchronized over the time
> (and over the net) to the cloned mail server, so the users can still
> access their mails while we deal with the primary server. My search leads
> me to the coda FS (and maybe the lustre solution, but we only use
> opensource soft so it may only be the one year old version - which is
> open...). Is there on the list people who are doing such things and if
> you are, can you give me some clues? What I think is something like a 'one
> read - multiple writes' FS who can handle the flow of mails and securely
> replicates it to the clone server. Do we have no choice but to tolerate
> the lost of some emails when the primary server stops responding? btw is
> it realistic?
> Thanks,
> Manuel
>
I've been looking into a similar configuration for our mail/DNS servers. One
option I've considered is http://www.linuxha.net/index.pl . They've got a
framework for using DRBD to maintain a replicated disk where only one node
can be writing or reading from it at a time. It doesn't have as many
features as Coda or Lustre, but it seems far simpler to configure and
administer.
Solving the inbound message problem isn't too bad as a standard backup MX
configuration will accept mails and forward them to the primary once it
re-appears, but the user's mail stores will be unavailable as long as the
primary is down.
I welcome other's thoughts on the matter.
