Hello,
I'm planning the transition of a single Exchange 2003 server to Exchange 2010. I understand there is no direct upgrade path but that I need to introduce 2010 into the environment and then move the mailboxes. My question is what is the effect of co-existence
to legacy Exchange 2003 server and the mailboxes hosted on them? Does external incoming/outgoing mail now need to pass through the 2010 server. If so then I assume I need to modify MX records to reflect the 2010 server? Can the 2003 instead continue to run
SMTP and forward/send email on behalf of 2010 mailboxes until I'm ready to fully transition?
The 2003 server also runs Activesync. I understand there is a legacy DNS setting that will cause users accessing mailboxes hosted on 2003 to automatically redirect to the correct server. In order for this to work properly however do certificates need be setup properly ahead of time? Is there a way to test that before I actually introduce the 2010 server into our Exchange organization? What if I gave the 2010 box a new OWA/Activesynce URL? Would that allow existing 2003 mobile devices to continue connecting to the 2003 sever until their mailboxes are moved? I know that I would need to manually reconfigure activesync clients but that's not a big issue as I only have a handful.
Ideally I would like to install the 2010 box and test the functionality of the new server without affecting the 2003 users at all. Once I have 2010 fully working then I would move the mailboxes and reconfigure Activesync as necessary.
Thanks for your advice.