I am looking at the following migration path for our Exchange environment, and would welcome comments regarding the viability of this plan.
Back End - Exchange 2003 Enterprise on Server 2003 SP2
Front End - Exchange 2003 Std on Server 2003 SP2 (SMTP Relay, OWA)
Front End - Exchange 2003 Std on Server 2003 SP2 (SMTP Relay for a different domain name, different IP address - this is for sending broadcast messages so our primary domain/IP doesn't get blacklisted)
Back End - Exchange 2007 Enterprise on Server 2008 (new hardware, Mailbox server role)
Front End - Exchange 2007 Std on Server 2003 SP2 (Edge Transport, Unified Messaging, Client access)
Front End - Exchange 2003 Std on Server 2003 SP2 (Edge Transport/SMTP Relay for a different domain name, different IP address - this is for sending broadcast messages & mass mailings so our primary domain/IP doesn't get blacklisted)
My plan as to get the new Exchange server up and running, migrate all the mailboxes from the old Exchange server to the new server, then upgrade the one front-end server from 2003 to 2007.
My questions are;
1. Are there any negatives or dangers to running this kind of a mixed Exchange environment?
2. Any problems running Exchange 2007 on either server 2003 or 2008?
3. Migration path seem OK? Any concerns with this plan?
4. My understanding is that for the front end servers I only need Exchange Standard, not Enterprise, correct?
5. And I don't need to worry about CAL's for the front-end servers, right? Just the back end server?