I'm building a Zimbra multi-server installation with 2 stores (using a SAN), 2 ldaps, 2 mta and 2 proxies. Each store has its owns sets of accounts (namespace splitted between servers). The HA of ldap, mta and proxies is easy and it's solved but store HA is a little complex.
Is there a way to merge all the accounts in one server on a node failure and restore them to the original place on failback? I know that I could have a third server as standby/backup of any mailstore but I don't want to have an idle server.