How to install Nagios on CentOS?

Setting Apache for Nagios

I assume you have installed Apache server. If you install via yum you don’t need to modify any thing, unless you want other options such as SSL configurations or allowing access to the CGI from only certain hosts, then the default nagios.conf file will suit your needs. Here’s what it looks like:

ScriptAlias /nagios/cgi-bin “/usr/lib/nagios/cgi”
#       SSLRequireSSL
Options ExecCGI
AllowOverride None
Order allow,deny
Allow from all
#       Order deny,allow
#       Deny from all
#       Allow from 127.0.0.1
AuthName “Nagios Access”
AuthType Basic
AuthUserFile /etc/nagios/htpasswd.users
Require valid-user
Alias /nagios “/usr/share/nagios”

#       SSLRequireSSL
Options None
AllowOverride None
Order allow,deny
Allow from all
#       Order deny,allow
#       Deny from all
#       Allow from 127.0.0.1
AuthName “Nagios Access”
AuthType Basic
AuthUserFile /etc/nagios/htpasswd.users
Require valid-user

Now apache is ready for Nagios and you need to setup authentication