Guys
We have a single Ex2003 32-bit server (no more than 500 mailboxes) in an isolated site with no OWA/Autodiscover requirement.
I am replacing this server with a 5 server Ex2010 platform consisting of 2 x HubCAS servers, 3 Mailbox Servers, and 2 Network Load Balancers.
The EX2003 server is on an old network (10.) and I am building the new 5 server platform on a new network (172.), these networks do not current talk to each other.
I have built the 5 EX2010 servers to OS level (Server 2012)and have the following questions.
Why can I not install EX2010 server roles onto Windows Server 2012 R2 servers as I have been told they will have to be Server 2012 Standard boxes? Not sure if there was a 32-bit - 64-bit OS conflict between Server 2003 and Server 2012?
Also, is it OK for me to install the Exchange 2010 roles onto the 5 servers whilst the 2 networks are separate, and then when bridging the two networks together for coexistence and mailbox migration will the 2 environments automatically start talking, or will I have do initiate the process?
In advance thank you for the support.
Windows 2008 was the last version of Windows Server that came in 32 bit version. Windows 2008 R2 and later is 64 bit only.
It sounds like you have two separate forests. If so, then you are doing a cross forest migration.
Cross forest is much easier between two Exchange 2010 servers. Therefore I would be looking to install an Exchange 2010 server in the existing domain where the Exchange 2003 server is, migrate everything to that server, then cross forest.
I would also cast some doubt on your design.
Splitting the roles up is no longer considered best practise. Why are you deploying separate CAS role servers if you are also deploying load balancers? I would drop the CAS completely and consider a three server design - three servers hold all three roles, in a three node DAG, active, active, passive.
The two load balancers can use all three servers for client access functionality.
Simon.