Ports RD Gateway uses

Encapsulates RDP in HTTPS packets listens on port 443 (for TCP) and port 3391 (for UDP)

 

Ports can be changed via RD Gateway Manager utility

1. Right-click the RD Gateway server name in the navigation pane and select Properties.
2. Select the Transport Settings tab.
3. Modify the HTTP and/or UDP port number.
4. Add firewall exceptions for TCP and UDP for the custom port

 

When you connect from a client, you need to add the custom port to the end of the gateway server name, preceded by a colon (:)