[CentOS] Moving sshd listen port

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I am having a problem getting sshd to run after changing it's default
port. I edit sshd_config and set the desired port, open it with
firewall-cmd and then issue a systemctl start sshd. No error gets
reported on the console but the following is logged in /var/messages

    sshd.service: main process exited, code=exited, status=255/n/a

Not a very helpful error message. Sounds like I should report a bug?

Thanks,
Mike

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/

iEYEARECAAYFAlO9UyAACgkQW1M1BMdnYxlRPwCgkdzu1RTBR26PSMXscy15Pf+y
U/MAoLrdInn/d/uySC/d6Dwh5ifkVvHg
=zy9z
-----END PGP SIGNATURE-----