Hi I am in the process of planning Exchnage 2010 deployment into an Exchange 2003/2007 Org. i am wondering how best to configure the legacy functions for the 2003 systems. I know i need to create a DNS record "legacy.domainname". Should this be the same IP as the existing IP that points to our OWA infrastructure? Also if so should I create a cname or an A record? Many thanks!

Hi, You can see the transition of owa and legacy setup in this article: http://msexchangeteam.com/archive/2009/11/20/453272.aspx And you can use the Deployment assistant from here: http://technet.microsoft.com/en-us/exdeploy2010/default(EXCHG.140).aspx#Home /MartinExchange is a passion not just a collaboration software.

Here's a good link for the coexistence information between 2003 and 2010 http://technet.microsoft.com/en-us/library/aa998186.aspx The Legacy DNS record should point to the 2003 server and the mail/owa/webmail record should point to the new server Jonas Andersson MCTS: Microsoft Exchange Server 2007/2010 | MCITP: EMA 2007/2010 | MCSE/MCSA Blog: http://www.testlabs.se/blog

Many thanks for your help! I am going to test this today

Hi i have tested this and all is working as expected so thanks for this! The only issue I am seeing is when I login to OWA now with a 2003 mailbox user I get a certificate warning. When I check the certificate it is the old certificate that is in use on the 2003/2007 servers. Do I need to replace the 3rd party cert I have on the 2007 CAS servers with the new cert for the Ex2010 servers (this contains "legacy.domainname" in the SAN field) Thanks again!

Hi, Yes you need to change the certificate on the Exchange 2003 so that it contains the legacy.domain.com name as subject alternate name. /MartinExchange is a passion not just a collaboration software.

Fantastic - that is working perfectly! Many thanks all!

Sorry chaps but one further question on this! We do not use split DNS so do I need an additional public IP and A record for "legacy.domainname"?

Hi, Yes you need an IP for the legacy.domain.com /MartinExchange is a passion not just a collaboration software.

Thank you for the help!