How to install Nagios on CentOS?

Starting Nagios Service

It is time to start Nagios

[root@yourmachine  nagios] chkconfig nagios on
[root@yourmachine  nagios] nagios -v nagios.cfg
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Output omitted…..
………
………
Reading configuration data…
Running pre-flight check on configuration data…
Total Warnings: 0
Total Errors:   0
Things look okay – No serious problems were detected during the pre-flight check

[root@yourmachine  nagios] service nagios start
Starting network monitor: nagios
Starting Nagios Failed:

So my friends you may not be very much lucky that you found Nagios services runing at this time, one problem you may face is Config Error.

[root@gw3 ~]# /etc/init.d/nagios status
No lock file found in /var/run/nagios.pid

[root@gw3 ~]# /etc/init.d/nagios start
Starting nagios:CONFIG ERROR!  Start aborted.  Check your Nagios configuration.

Don’t go away I have solution of above problem Configure SELINUX for Nagios Daemon or just disable SELINU