Hi Samuel -
Unity only partners with one Exchange server, which hosts the mailbox used for handling calls from external callers. But one Unity server can support subscribers on multiple Exchange servers. We are doing that today in our environment. Here are some things to consider, in which case you'd want to consult the Unity Design Guide for your version:
- Are your Exchange servers in the same subnet as Unity? If not, is there <40 ms. response time between Unity and both Exchange servers? This is just one performance indicator that should be investigated.
- Are the Exchange servers in the same AD forest/ Exchange organization and Exchange administrative group? If in different administrative groups, the design recommendation is for each administrative group to have its own Unity server.
- Unity platform - depends on how many subscribers can be hosted on the server
- There used to be guidelines for the number of information stores that could be supported by one Unity server. I'm not 100% sure, but I don't believe that is still a consideration if the performance between Unity and Exchange is good. As always, when I'm not sure, I check with TAC :-)
Sincerely,
Ginger
