Ubuntu ssh server

Apparently, ubuntu is using systemd-sockets for quite some time, so the way to change the default ssh port has changed.

Here’s how do it:

• touch /etc/systemd/system/ssh.socket.d/listen.conf
• Put the following in it:

  cat <<EOF > /etc/systemd/system/ssh.socket.d/listen.conf
  [Socket]
  ListenStream=
  ListenStream=14453
  EOF
  

That first ListenStream= is necessary to remove the default port (22). If you don’t do that, the ssh deamon will listen on both port 22 and 14453 (in this example).

Source: https://serverfault.com/a/1159600