I upgraded my 2010 Exchange environment to 2019. My 2010 environment had 1 CAS & 2 Mailbox servers setup with a DAG. No Edge server.
My new Exchange 2019 environment has 2 Mailbox servers with a DAG. There is no Edge server, but I am starting to see that this configuration cannot work without one. Otherwise, if one Mailbox servers goes down, how does traffic get routed to the other Mailbox server. Even with the DAG working correctly, if a reboot my main Mailbox server all internal Outlook clients go offline until the server is back up. I was hoping to not use an Edge server to keep things very simple.
I think I made an error in this design, and wonder if someone could point me in the right direction.