[CentOS] One server not showing SSH port, the other is.

Tue Oct 12 22:56:27 UTC 2010
Phil Schaffner <Philip.R.Schaffner at NASA.gov>

Ryan Manikowski wrote on 10/11/2010 07:49 PM:
> One method to obscure the presence of the ssh daemon would be to use
> port knocking:
> http://dotancohen.com/howto/portknocking.html

Somehow I suspect the OP may have seen that one. :-D