I seem to be having difficulty when our role holder switches to another server located on a different subnet.
2 mail servers on the 10.3.1.x subnet
1 mail server on the 10.3.241.x subnet
When the role holder transfers to the 10.3.241.x subnet mail clients can no longer connect.
I have a "mail" and "autodiscover" DNS entry that points to my DAG address of 10.3.1.61 so I understand when it fails over things should stop working. So I created a round robin setup of mail and autodiscover for the 10.3.241.61 DAG IP. However, that IP is offline unless the role holder is the 10.3.241.x server. Today during my test, clients got the 10.3.241.61 address for mail and autodiscover so their clients could not connect.
I've read that I don't need a Mail or Autodiscover DNS entry to I tried deleting them and configuring and outlook client. I locates the mail server but fails to connect. So, I have a hot mess and I am sure this is clear as mud but I need to start somewhere to get this cleaned up and working.