Nagios centos 6.5

INFO: Nagios3 is not included in base centos repositories, you need to install rpmforge repository

You can install nagios4 from sources as described here: https://www.voipmonitor.org/doc/Nagios_4

Installation using rpmforge:

Install RPM forge for centos 6 (http://wiki.centos.org/AdditionalResources/Repositories/RPMForge#)

For x86_64:

wget http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm
rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt
rpm -i rpmforge-release-0.5.3-1.el6.rf.*.rpm

For i686:

wget http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.i686.rpm
rpm --import http://apt.sw.be/RPM-GPG-KEY.dag.txt
rpm -i rpmforge-release-0.5.3-1.el6.rf.*.rpm

Install nagios plugins:

yum install nagios
yum install nagios-plugins

Edit and add line into nagios configuration vim /etc/nagios/nagios.cfg

cfg_file=/etc/nagios/objects/vm.cfg

Change privileges for nagios and voipmonitor

touch /etc/nagios/objects/vm.cfg
chown apache /etc/nagios/objects/vm.cfg

vim /etc/sudoers check option and add line apache ...

Defaults requiretty
apache  ALL=(nagios) NOPASSWD: ALL

chown -R nagios:nagios /var/nagios/spool/checkresults