We are migrating to Exchange 2010 from Exchange 2003.
We have 2 Exchange 2003 server in an active-passive cluster and 2 OWA servers. The people that built the OWA server didn't use NLB so they are independent and they can only provide webmail service one at the time.
The Exchange 2010 configuration is:
-We have combined the CAS and HT server in 2 servers so we have created 2 CAS/HT servers named CASHT01 and CASHT02. We have also created a CASRRAY potining to CASHT01 and CASHT02 (we use a LoadBalancer Solution)
-We also have 2 Mailbox servers with a single DAG.
We use Google Postini as Spam Filer so everything so our MX records are pointing to them and once our emails gets sanitized is being forwarded to our servers.
We don't have ISA/TMG on the current env. and we will not use it for the Exchange 2010 either.
Currently for Exchange 2003 the public DNS and firewall are configured as follows:
mail.domain.com (Inbound SMTP/25) -> 22.214.171.124 Nated to -> 172.20.200.10 (Exchange 2003 cluster VIP)
webmail.domain.com -> 126.96.36.199 Nated to -> 172.20.200.11(OWA1)
With Exchange 2010 we are planning to change the public DNS and the firewall as follows:
mail.domain.com (inbound SMTP/25) -> 188.8.131.52 Nated to -> 172.20.200.38 CASARRAY (CASHT01/02 the Hub Transport servers with the receiving/sending connectors)
webmail.domain.com -> 184.108.40.206 Nated to -> 172.20.200.38 CASARRAY (CAS server hosting the WebApp, etc..)
Finally new additions to the public DNS and the firewall are
autodiscover.domain.com - > My understanding is that this record has to point to the CAS servers in our case it will be the CASARRAY – 172.20.200.38
legacy.domain.com -> My understanding is that this record has to point to an Exchange 2003 front end. In our scenario we are going to have to have to use a new public IP and use a NAT to the DMZ where the OWA server is sitting at.
sync.domain.com -> Point the record to CASARRAY 172.20.200.38
Could someone please review the changes that we are planning to do and let us know if they are correct?
Here is my background information: