I have a multiserver zimbra install setup. Our domain uses external ldap authentication.

Recently we've started using round robin DNS to spread the ldap requests across two replicated ldap servers.

The issue is that the zimbra servers (2 store servers) seem to latch on to one of the two ldap servers, and send all of their auth requests to that server. Ignoring the second host in the round robin.

Does zimbra maintain some sort of DNS cache? Or does it maintain a persistent connection to the ldap server?

How can I convince zimbra to spread out the auth requests?