Nagios installation step by step in centos/redhat or fedora part 1

What is Nagios?

Nagios is a powerful monitoring system that enables organizations to identify and resolve IT infrastructure problems before they affect critical business processes.

 It has the capability of monitoring application, services, entire IT infrastructure. It has been designed with scalability and flexibility in mind, Nagios gives you the peace of mind that comes from knowing your organization’s business processes won’t be affected by unknown outages.

Nagios is a one of the best open source tools available in the market that provides you with instant awareness of your organization’s mission-critical IT infrastructure. Nagios allows you to detect and repair problems and mitigate future issues before they affect end-users and customers.

Installation Steps:

Step 1: Install Dependencies and Required Packages

We are assuming that you have fresh installed CentOS, Red hat or Fedora systems, So our first requirement is to install LAMP . You have not installed LAMP server, Please click here for LAMP installation steps or Click on the below link.

Install Packages:

# yum install httpd php php-cli gcc glibc glibc-common gd gd-devel net-snmp

Start Services:

# service httpd start

Step 2: Create User Accounts

Now create a new nagios user account and setup a password to this account

# useradd nagios

# passwd nagios

Now create a groud for nagios setup “nagcmd” and add nagios user to this group. Also add nagios user in apache group.

# groupadd nagcmd

# usermod -a -G nagcmd nagios

# usermod -a -G nagcmd apache

Step 3: Install Core Service

After installing required dependencies and adding user accounts. Lets start with Nagios core installation. Download latest nagios core service from official site.

# cd /opt/

# wget

# tar xzf nagios-4.0.8.tar.gz

# cd nagios-4.0.8

# ./configure –with-command-group=nagcmd

# make all

# make install

# make install-init

# make install-config

# make install-commandmode

Now use below command to setup apache configuration for Nagios installation.

# make install-webconf

Step 4: Configure Apache Authentication

We need to setup apache authentication for user nagiosadmin. Do not change this username. else you would required more changes in configuration.

# htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin

Now restart Apache service to make the new settings take effect.

# service httpd restart

Step 5: Install Nagios Plugins

After installing and configuring Nagios core service, Download latest nagios-plugins source and install using following commands.

# cd /opt

# wget

# tar xzf nagios-plugins-2.0.3.tar.gz

# cd nagios-plugins-2.0.3

Now compile and install nagios plugins

# ./configure –with-nagios-user=nagios –with-nagios-group=nagios

# make

# make install

Step 6: Verify and Start Nagios

Use the following commands to verify nagios install and start nagios core service.

# /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg

# service nagios start

Also configure nagios service to start on system start

# chkconfig –add nagios

# chkconfig nagios on

Step 7: Access Nagios in Web Browser

Nagios creates its own apache configuration file /etc/httpd/conf.d/nagios.conf. There are no need to make any changes to it. Simply open below url in browser.
[change your domain or ip]

Login with new created login credential.


Now you have successfully installed and configured Nagios core service in your system.



Satya Prakash

VOIP Expert: More than 8 years of experience in Asterisk Development and Call Center operation Management. Unique Combination of Skill Set as IT, Analytics and operation management.

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