we are looking into several options for our mail system. Domino vs Zimbra NE. Zimbra NE lists high availability as one of its features. I would like to know if setting up a Red Hat cluster is the only way to get several Zimbra mailstore servers to be the replicas of each other? Or would it be enough just to go with the multi server installation?

Domino is very good in maintaining replicas of the mailboxes on various servers with minimal config. At a price though. Can it be achieved with Zimbra relatively easily, because judging by the RH cluster installation document, expensive hardware like SAN is required for a successfull deployment.

Thank you.