How to connect to an SSH server using an alternate port

While the standard port for SSH servers is 22, there are instances when it may be necessary to use an alternate port. This can be for security purposes or to accommodate other preferences or limitations.

There is no need to specify the port number if connecting to the default port. However, to connect to an SSH server on a custom port, you need to use the -p option or specify the port in the SSH client's configuration file.

1. Determine the port the SSH server uses.

   Related: How to modify the SSH server port
   Related: How to operate an SSH server on multiple ports

2. Check if the client host can reach the server's listening port (optional).

   $ nc -zv remotehost 2022
   Connection to remotehost 2022 port [tcp/*] succeeded!

   -v      Produce more verbose output.
   -z      Only scan for listening daemons, without sending any data to
           them.  Cannot be used together with -l.

3. Use the -p option to specify the port when connecting.

   $ ssh remoteuser@remotehost -p 2022

4. Add the port directive to the SSH client configuration file for persistent connection option.

   $ cat .ssh/config
   Host remotehost
       hostname 192.168.1.10
       user remoteuser
       port 2022

5. Connect again using the SSH client and the host name, without providing the port number as a parameter.

   $ ssh remotehost