We are in the process of merging 4 companies together. For the focus of this question, our concern is to create a solution to utilize a single domain address, with the least amount of work for phase 1. Long term solutions will be adopted during phase 2.
@corp.com, 15-25 users, POP Mail, Web/Hosted
@corp1.com (will be host starting phase 2), 100 users, Exchange 2010, Server 2008 R2
@corp2.com, 50-75 users, Exchange 2010, Server 2008 R2
@corp3.com, 50-75 users, Exchange 2003, Server 2003
At the launch of Phase 1, all companies will adopt the domain address @corp.com.
Our initial thought is to start with putting the existing @corp.com users into an exchange environment. We could export/import their existing mail into a new mailbox hosted on the @corp1.com mail server.
From there, it seems to be a matter of configuring each companies Exchange server to share an SMTP address space. Is this correct?
At each location would we add a @corp.com SMTP address and set as primary?
Would we point all of our MX records to @corp1.com exchange server?
Thanks for the help!