SSH Server Hardening in one of the security part to secure your server.Refer following steps to secure SSH.

root@serevr[~]#pico /etc/ssh/sshd_config

Uncomment  #Protocol 2, 1

Change to Protocol 2

Append these lines to the bottom:

LoginGraceTime 120
IgnoreRhosts yes
X11Forwarding no
Save file and restart the SSH service.

root@serevr[~]#/etc/rc.d/init.d/sshd restart

Note : SSH Protocol one  based servers are facing many automated root kits attacks.As a result to step up the security Protcol 2 should be enabled on server.The reason to use SSH Protocol 2 on any webserver is that it is more secure as compare to protocol 1.