How to install Nagios on CentOS 7

In this article, we will discuss how to install Nagios on CentOS 7. Nagios is a powerful monitoring system that can help you keep track of your network resources, services, and applications.

Before we begin, make sure that you have root access to the server you will be installing Nagios. You should also have a basic understanding of Linux commands.

Important: Disable SELinux On CentOS:

sudo sed -i 's/SELINUX=.*/SELINUX=disabled/g' /etc/selinux/config

Step 1: Update Your CentOS 7 Server

Before you install Nagios on CentOS 7, it’s important to update your CentOS 7 server to ensure that all the latest packages are installed. To do this, run the following command:

sudo yum update -y

This will update all packages on your CentOS 7 server.

Step 2: Install the Required Dependencies

Next, we need to install some dependencies that Nagios on CentOS 7 requires. Run the following command:

sudo yum install gcc glibc glibc-common wget unzip httpd php gd gd-devel perl postfix

This command will install Apache, PHP, and some other dependencies that Nagios on CentOS 7 needs.

Step 3: Download and Compile Nagios

Next, we need to download Nagios and compile it on our CentOS 7 server. Run the following commands:

cd /usr/src/
sudo wget -O nagioscore.tar.gz https://github.com/NagiosEnterprises/nagioscore/archive/nagios-4.4.5.tar.gz
sudo tar xzf nagioscore.tar.gz
cd nagioscore-nagios-*/
./configure
sudo make all

Step 4: Create a Nagios User and Group

We need to create a Nagios user and group on our CentOS 7 server. Run the following commands:

sudo make install-groups-users

sudo usermod -a -G nagios apache

Step 5: Install Binaries, HTML, and CGIs files

sudo make install
sudo make install-daemoninit
systemctl enable httpd.service
sudo make install-commandmode
sudo make install-config
sudo make install-webconf

Step 6: Create Nagios Web User

sudo htpasswd -c /usr/local/nagios/etc/htpasswd.users nagiosadmin
sudo systemctl restart httpd

Note: You can use our password generator: click here

Step 7: Access Nagios Web Interface

Finally, we need to access the Nagios web interface to make sure that everything is working properly. Open a web browser and go to:

http://your_server_ip/nagios

Step 8: Download and Compile Nagios Plugins

Nagios Plugins are a collection of over 50 plugins that Nagios uses to monitor various network resources. We need to download and compile Nagios on CentOS 7 Plugins. Run the following commands:

sudo yum install -y gcc glibc glibc-common make gettext automake autoconf wget openssl-devel net-snmp net-snmp-utils epel-release

sudo yum install -y perl-Net-SNMP

cd /usr/src/
sudo wget --no-check-certificate -O nagios-plugins.tar.gz https://github.com/nagios-plugins/nagios-plugins/archive/release-2.2.1.tar.gz
sudo tar zxf nagios-plugins.tar.gz
cd nagios-plugins-release-2.2.1
sudo ./tools/setup
sudo ./configure
sudo make
sudo make install

Restart the Nagios service

sudo systemctl restart nagios
sudo systemctl status nagios