Need advice on building a Cyrus IMAP cluster

[Michael Sims]

Hi Dave,

Thanks for taking the time to respond.

Dave McMurtrie wrote:
> When I worked at the University of Pittsburgh, we set up a 4-node,
> active/active Cyrus IMAP cluster.  It ran on Sun v440 servers running
> Solaris 8 using Veritas Cluster Filesystem.  If you need additional
> details about that setup, pop me an e-mail.

Yes, I've seen you talk about this in the archives.  However, we will be
using linux for various reasons so I'm limited to what is available for it.

> I think BDB may use shared memory, which
> definitely won't work across cluster nodes using only a distributed
> filesystem.  If this is the case, BDB just can't be used.

Yeah, I've read enough in previous threads to know to not compile BDB
support into Cyrus if I'm going to try to use it over a shared file system.

> As of Cyrus 2.3, the code supports the notion of application-level
> replication.  It's near real-time replication of all the application
> data, but one copy of the data isn't live.  This is more of an
> active/passive solution, since you have to do something to make cyrus
> aware of the 2nd copy of the data if you suffer some type of failure
> of
> the first copy.

Ah, I see, thanks for the clarification, that is helpful.

Overall, my general feeling is that active/active is still a bit too
bleeding edge for me to recommend it to my boss.  I know that it has been
done, but it seems to be relatively uncommon.  I might try to toy around
with it in a lab environment for kicks, but I think I'm going to lean
towards an active/passive to be on the safe side.

Thanks for your help, I really appreciate it.

Michael Sims