Can I use SSH on a port other than the default port 22?

You can use another port aside from the default. There are two methods to do so, either on the client side or the service side.

On your server add or edit the following line to your /etc/ssh/sshd_config with the port number:

    Port 22

Whenever SSH to registered hosts they pass the -p flag to specify the non-default port.

Alternatively, update your local step SSH configuration at ~/.step/ssh/config to always use this port for Smallstep-managed hosts.

Match exec "step ssh check-host %h"
  User yourname
  UserKnownHostsFile "/Users/yourname/.step/ssh/known_hosts"
  ProxyCommand step ssh proxycommand --provisioner "sso-ssh" %r %h %p
  Port [non_default_port_number_here]