Its possible to enable SSL over http for Nagiso Core (Red Hat/CentOS). The Nagios WEB UI can be made secure by enabling https instead of plain http in Nagios. After you are done installing Nagios Core in Linux, you need to enable OpenSSL in Apache. First we need to install mod_ssl and openssl and then edit nagios.conf in Apache.
Run this command
# yum -y install mod_ssl openssl
And then hash out "#" SSLRequire fields in nagios.conf
# vi /etc/httpd/conf.d/nagios.conf
That's it. EASY isn't it !!. Now go ahead and access Nagios WEB UI over "https".
If you encounter any errors during the process, let us know via Contact Us and will get it resolved promptly.