> As per the installation instructions I ran the commands in the concerned > folders of ./configure , make , make install for both the core and the Nagios > plugins. > > I am not able to figure out the issue behind that it is not working It did got > installed using yum which was a previous 4.3.2 that that had it's own errors > and wanted me to update with no update of it available in the epel > repository. What's not working? Did it compile correctly? Nagios needs some extra packages to for all of its features to work. These can be installed via YUM even if you compile Nagios itself from source. Also, if you install Nagios from source, SELinux will prevent it from doing a lot of stuff by default. However, it's entirely possible to run Nagios with SELinux in Enforcing mode with the right policy.