Installing OpenNMS: A Comprehensive Guide

OpenNMS is an open-source network management platform designed to monitor and manage large-scale networks. This guide will walk you through the steps required to install OpenNMS on a Linux-based system. By the end of this tutorial, you’ll have OpenNMS up and running, ready to monitor your network effectively.

Prerequisites

• A server running CentOS or Ubuntu.
• SSH access to the server.
• Basic knowledge of Linux command line.
• At least 4GB of RAM and 20GB of disk space.
• Java 11 or later installed on your server.

Step-by-Step Installation

Step 1: Update Your System

Before we begin, ensure that your system is up to date. On Ubuntu, run:

sudo apt update && sudo apt upgrade -y

On CentOS, use:

sudo yum update -y

Step 2: Install Java

OpenNMS requires Java to run. If Java is not installed, you can install it using the following commands:

On Ubuntu:

sudo apt install openjdk-11-jdk -y

On CentOS:

sudo yum install java-11-openjdk -y

Step 3: Add the OpenNMS Repository

Add the OpenNMS repository to your package manager. This will allow you to install and update OpenNMS using system package managers.

For Ubuntu, create a new file:

echo 'deb https://debian.opennms.org stable main' | sudo tee /etc/apt/sources.list.d/opennms.list

For CentOS:

sudo yum-config-manager --add-repo=https://yum.opennms.org/stable/common/opennms.repo

Step 4: Install OpenNMS

After adding the repository, install OpenNMS with the following commands:

On Ubuntu:

sudo apt update 
 sudo apt install opennms -y

On CentOS:

sudo yum install opennms -y

Step 5: Initialize and Start OpenNMS

Initialize the OpenNMS database and start the service:

sudo /opt/opennms/bin/runjava -s 
 sudo /opt/opennms/bin/install -dis 
 sudo systemctl start opennms

You can now access OpenNMS through your web browser by navigating to http://localhost:8980/opennms.

Troubleshooting Common Issues

If you encounter issues starting OpenNMS, check if all required services are running:

sudo systemctl status opennms

Ensure that your firewall allows traffic on port 8980, used by OpenNMS web interface.

If Java versions conflict, set the Java home explicitly:

sudo update-alternatives --config java

Summary Checklist

• Ensure all system updates are applied and Java is installed.
• Configure OpenNMS repository and install the package.
• Initialize OpenNMS database and start the service.
• Access OpenNMS web interface through your browser.

For alternative network monitoring solutions, check out our dedicated guide on How to Configure Nagios Hosts.