So What's changed in Exchange 2013?
Now that Exchange 2013 has been GA for sometime now, I am sure some of you must have already tried playing with it. Although Exchange 2013 cannot be in implemented to co-exist with Exchange 2007 or Exchange 2010 yet (the co-existence SP for Exchange 2010 and RU for Exchange 2007 are expected to be released this quarter as per an Exchange Team announcement), you can implement it as a greenfield environment or in your test lab and start plying with it. Although greenfield Exchange 2013 might not be an option favored by many, testing and familiarizing yourself with Exchange 2013 is certainly a great opportunity while we await the co-existence components release.
I quickly wanted to list some of the changes in Exchange 2013 in comparison so Exchange 2010 and 2007.
1. Outlook now connects to the CAS servers only using RPC/HTTPS (Outlook Anywhere).
2. "RPCClientAccessServer" attribute is now deprecated. However, the RPC Client Access Array introduced in EX2010 still exists in EX2013 and needs a load balancer to load balance the client connections. That said, the recommended load balancing method in Exchange 2013 is IP-based only . The CAS servers take care of the session affinity for you. Hurray! no more struggles to get the load balancer configuration right!
3. There are only 2 roles available in EX2013 - 1. Client Access Server role 2. Mailbox Server Role
4. Exchange Administration Console (EAC) is the new administration console in EX2013. It is now a web based console.
5. The Hub Transport server role functionality that existed in Ex2010 and EX2007 has been now moved into the Mailbox Server role.
6. The CAS server is Ex2013 is a stateless proxy that essentially proxies all the protocols back to the MBX server. Your client connections are all now held on the mailbox server unlike on the CAS server in EX2010. Also the Outlook connection point is now the Mailbox GUID of the particular user and not the Exchange server name. This ensures that the end users no longer get the "Your Administrator has made a change to your mailbox. Please restart your outlook" when you make back end maintenance work like moving their mailbox. This is because the mailbox GUID remains the same throughout the life of the mailbox.
7. The protocol head has been moved to the MBX server. Prior to EX2013, the protocol head existed on the CAS and MBX servers for client connections along with the HT server role for transport.
8. The transport service has been split into two services now 1. Transport Submission service 2. Transport Delivery service. Both are mutually exclusive services hence even if the Submission service is mal-functioning, Delivery service will not be impacted.
9. The store process has be re-written in managed code making it more efficient. Also each database gets its own store worker process now which are managed by a host Store process.
10. Exchange 2013 now leverages FAST search technology.
-Ary