I have a Unity 4.2 UM client contained to a single AD forest/Exchange 2003 organisation (UUU.NET)- the same domain is used for corporate user accounts. We are now going to build a separate AD forest/Exchange 2007 organisation using Microsoft's documented Exchange Resource topology (XXX.NET). Users will continue to use UUU.NET as their account forrest but their mailbox will be assoiated with the Exhagnge 2007 cluster in a different forest, ie XXX.NET. A user provisioning process will allow new accounts created in the UUU.NET forest to appear in the XXX.NET forest with an associated mailbox. I believe the user accounts in the XXX.NET domain will be disabled.
I plan to build a new Unity 7 server integrated with the new 2007 message store. I will also create a new switch integration with the existing CallManager 4.2 server (new VM config, profiles, etc). The existing Unity 4.2 server will remain in situ during the migration. Assuming I have successfully completed the Unity 7 install and the user provisioning process has replicated my users between the UUU.NET and XXX.NET forest/domains can I use the COBRAS tool to import my subscribers/greetings etc in to the Unity 7 database - for now I'm assuming the same Exchange alias will exist in both Forests. Do you foresee any issues with using this approach? Is there anything I need to prep before running COBRAS? At the moment it looks too good to be true