At this point we need to change the SMTP feed from the old Exchange Server 2010 box to the new Exchange 2013 Server, below are the simple steps:
- Change the SMTP (TCP Port 25) port redirect on your router/firewall.
- Swap IP addresses from the old to the new server.
- Change the translation from public to private IP address to point to the new IP.
- If you have any mail scanning servers, anti-spam hardware devices etc, then you will also need changing to point the new server.
- Now you have to do some changes on your Exchange 2013 ECP, such as add the new server to your Exchange “Send Connector” and remove the Exchange 2010 server (here assumption that only one send connector, if you have more than one such as secure TLS mail, you need to do these as well).
- Open Exchange 2013 Admin Center --> Mail Flow--> Send Connectors--> Send Connector--> Edit-->Scoping-->Add the 2013 server-->Remove the 2010 server--> save