Tech Chorus

If you have freshly install CentOS - 5.3 and if you trying to install Nagios on the same then refer this link mentioned below this works like a gem.

http://www.linux4beginners.info/node/nagiosfedora

Before you start up with the installation of nagios on CentOS 5.3 my recommendation is that you stop your firewall and disable SELinux.

Command to check the status of the firewall on CentOS 5.3 - service iptables status

Command to check the status of the firewall on CentOS 5.3 - service ip6tables status

To stop your firewall services on CentOS 5.3 just type "stop" instead of "status" in the above mentioned command.

Command to disable SELinux - setenforce 0.