I have an exchange server 2003 that currently shares a public IP with a web server xxx.xxx.xxx.200. Our firewall uses port forwarding for OWA. All http and https are forwarded to the web server, and all 8650 is forwarded to our exchange server for OWA.
What I want to do: I want to move the exchange server to a different public IP xxx.xxx.xxx.201, without causing any interuption to email delivery (or website). I was thinking that I would create a second MX record (20) to point to the .201 public address, which would mean I would add an additional NIC on my Exchange and do a 1to1 NAT to the .201 address. I would wait for a week for the second MX record to replicate on the internet and then delete the first MX record that points to the .200 IP.
Is this the proper way to do this.