I am looking to migrate my exchange 2010 environment to 2013.
In the process I will be changing my namespace to be more generic
From Exchange2010.mycompany.com
To Mail.mycompany.com
So when I setup my urls for 2013 I will be setting internal and external to Mail.mycompany.com and setting dns and auto discover as well.
I'm assuming that since I will be proxying through 2013 I will also change my existing exchange2010.mycompany.com dns to point to the 2013 server load balancer.
The question is What should I do with my exchange 2010 internal and external urls on the 2010 cas servers ? I have seen migration guides that don't mention this step and others that say I need to set them to null... If null internal or external?
Thanks