Nagios in Oracle Linux

Nagios is an open-source monitoring system that helps organizations to monitor the availability and performance of their IT infrastructure, including servers, applications, services, and network devices. Nagios provides a centralized view of the entire IT infrastructure, allowing administrators to quickly identify and resolve problems before they impact the end-users.

Nagios uses plugins to monitor the status of hosts and services, and can be configured to send notifications via email, SMS, or other means when problems are detected. It also provides trend analysis and capacity planning features that help administrators to anticipate and prevent potential problems.

Nagios has a modular architecture and is highly customizable, allowing users to develop their own plugins, extensions, and customizations. It has a large community of users and developers who contribute to its development and share their knowledge and experience through forums, blogs, and other channels. Nagios is widely used in both small and large organizations to ensure the availability and reliability of their IT infrastructure.

Installing

Here are the steps to install Nagios on Oracle Linux:

1. Install the required dependencies:

    sudo yum install httpd php gcc glibc glibc-common gd gd-devel make net-snmp openssl-devel wget unzip
   

2. Create a user and group for Nagios:

    sudo useradd nagios
    sudo groupadd nagcmd
    sudo usermod -a -G nagcmd nagios
    sudo usermod -a -G nagcmd apache
   

3. Download and extract Nagios:

    wget https://github.com/NagiosEnterprises/nagioscore/archive/nagios-4.4.6.tar.gz
    tar -zxvf nagios-4.4.6.tar.gz
    cd nagioscore-nagios-4.4.6/
   

4. Configure and install Nagios:

    ./configure --with-command-group=nagcmd
    make all
    sudo make install
    sudo make install-init
    sudo make install-commandmode
    sudo make install-config
    sudo make install-webconf
   

5. Create a Nagios administrator account:

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

6. Download and install the Nagios plugins:

    cd ~
    wget https://nagios-plugins.org/download/nagios-plugins-2.3.3.tar.gz
    tar -zxvf nagios-plugins-2.3.3.tar.gz
    cd nagios-plugins-2.3.3/
    ./configure --with-nagios-user=nagios --with-nagios-group=nagios
    make
    sudo make install
   

7. Start the Apache web server and Nagios service:

sudo systemctl start httpd
sudo systemctl start nagios

You can now access Nagios by navigating to http://[your-server-IP-address]/nagios/ in a web browser, using the username nagiosadmin and the password you created in step 5.

STIG Compliance

The Security Technical Implementation Guide (STIG) is a set of guidelines created by the Defense Information Systems Agency (DISA) for securing computer systems. Here are the steps to make Nagios STIG compliant:

1. Update Nagios to the latest version to ensure that any security vulnerabilities are patched.
2. Harden the operating system by following the appropriate DISA STIG for your operating system.
3. Configure Nagios to use SSL encryption for web traffic to prevent interception of sensitive data. To do this, generate a self-signed SSL certificate or obtain a certificate from a trusted certificate authority, and configure Apache to use SSL.
4. Restrict access to Nagios to only authorized users by configuring Apache to use password authentication, and create separate accounts for each user with the appropriate access levels.
5. Configure Nagios to use secure passwords by enforcing a password policy that requires passwords to be at least 8 characters long, include uppercase and lowercase letters, numbers, and special characters.
6. Enable logging in Nagios and configure log rotation to ensure that log files are not retained indefinitely.
7. Disable any unnecessary services or plugins in Nagios to reduce the attack surface.
8. Regularly scan Nagios for vulnerabilities using a vulnerability scanner or manually reviewing logs for suspicious activity.
9. Monitor and review Nagios logs regularly for any signs of unauthorized access or other security breaches.

By following these steps, you can make Nagios STIG compliant and improve the overall security of your IT infrastructure.