By "it seems to require a UDP connection", OP really meant that Mosh requires the server to have an open UDP port so the client can send it packets. Practiacll

By "it seems to require a UDP connection", OP really meant that Mosh requires the server to have an open UDP port so the client can send it packets. Practiaclly, this means that if your server is behind a firewall or NAT, you need to poke a hole in your firewall to be able to connect with Mosh.