Here are couple ways to change your sshd default configuration settings and make / Secure ssh daemon more secure / restrictive and thus protect your server from unwanted intruders.
Everytime you make changes in the sshd configuration file you need to restart sshd. By doing so, your current connections will not be closed ! Make sure that you have a separate terminal open with root logged-in in case you do some misconfigurat...
By tapish01, June 26, 2015