HI Joe.
Theres no clean way to setup 2.4.0 in a fail over configuration since greetings cannot be easily replicated between the two boxes. When the primary box goes down and the secondary box picks up calls, they will be routed to the failsafe in some situations which is clearly not acceptable.
2.4.5 changed the greeting storage scheme such that the directory on the hard drive that stores the greetings can simply be setup to replicate between the primary and secondary Unity boxes allowing a simple fail over scheme to be possible. This will require, of course, that users be homed on an Exchange box external to both Unity boxes. If you have messages stored on the Exchange server on the primary Unity box and that goes off line, youre obviously not going to be able to get at them.
Theres no load balancing capability in Unity at this time. A sea of Unitys project is under way that will put the framework in place to support a clustering type functionality that will allow balancing and much more robust failover capabilities but theres still much work to be done before thats ready for prime time. I dont have a target release date for that at this point.
Jeff Lindborg
Unity Product Architect
Active Voice
jlindborg@activevoice.com
http://members.home.net/jlindborg