Installing Nagios

Introduction Prerequisites Installation Steps Configuration FAQ

1. Introduction

Nagios is an open-source monitoring system that enables organizations to identify and resolve IT infrastructure problems before they affect critical business processes.

2. Prerequisites

Before You Begin

Linux-based server (Ubuntu, CentOS, etc.)
Root or sudo access
Basic knowledge of command line operations

3. Installation Steps

Step-by-Step Installation

Update the package index:
```
sudo apt update
```

Install required packages:

sudo apt install -y apache2 libapache2-mod-php7.4 php php-gd php-cli php-mbstring php-xml php-bcmath php-ldap php-mysql

Create a nagios user and group:
```
sudo useradd nagios
```

Download and extract Nagios Core:

wget https://github.com/NagiosEnterprises/nagioscore/archive/refs/tags/4.4.6.tar.gz
tar -xzf 4.4.6.tar.gz
cd nagioscore-4.4.6

Compile and install Nagios:

./configure --with-command-group=nagios
make all
sudo make install

Install the command mode:
```
sudo make install-commandmode
```
Install Nagios init script:
```
sudo make install-init
```
Start Nagios service:
```
sudo systemctl start nagios
```

4. Configuration

After installation, configure Nagios by editing the main configuration file located at /usr/local/nagios/etc/nagios.cfg.

Note: Ensure that you set correct paths and permissions to avoid errors.

5. FAQ

What is Nagios used for?

Nagios is primarily used for monitoring system performance, network traffic, and availability of services.

Is Nagios free?

Yes, Nagios Core is open-source and free to use, but there are paid versions with additional features.

Can Nagios monitor remote servers?

Yes, Nagios can monitor remote servers using plugins and agent-based monitoring techniques.