January 7, 2025

Best Practices to Upgrade OS with Nagios Fusion

Andy Fried

Technical Support Manager

Reasons for Migrating to a Different OS

There may be various reasons why you need to migrate from one Linux version or platform to another. These may include the current platform/version reaching EOL, the need to overcome certain security/functionality issues, upgrading components to major versions (PHP 7.x -> 8.x), internal standards, and so on. This document contains information and links to allow you to plan and perform migrations from one OS version to another.

Importance of Backups and Testing

Since Nagios Fusion is a flexible product and all systems/environments are different we strongly recommend making a backup and testing all migration steps on your Test server before making any changes in production. If you don’t have a test server setup already please see our notes below on how to set one up.

Upgrade OS: Setting Up a Test Server

First, our software does not support an in-place OS upgrade. This will cause problems with dependencies and will result in a number of issues including Fusion components failing to function correctly. The reason is that when you initially install Fusion, the installation scripts identify the OS and other components (PHP version, etc) and adjust the scripts/code accordingly. If you upgrade in place, Fusion will still try to use what it learned during its initial installation and may break due to upgraded OS components.

Recommendations for OS Migrations

The recommendations below are based on CentOS7 upgrades to CentOS Stream/RHEL 8/9. However, they do apply to any Linux distribution where Nagios Commercial software is supported, including inter-distribution upgrades/migrations such as CentOS7 to Ubuntu 22.04 TLS or Ubuntu 18.04 TLS to Debian 11.

Since each Fusion license comes with the ability to install on three instances (see License Information document, below), we recommend setting up a new Linux system/image with CentOS Stream/RHEL 8/9 (if you decide to stay with CentOS/RHEL) as a test server. Then install the same version of Fusion that you are running on the current production system. Once installed, you should be able to replicate your configuration through the backup and restore process (document below) by backing up your current Fusion configuration and restoring it to the new system.

Migrating Between Distributions

Depending upon the version of Fusion you currently have installed you may need to “step” into the migration and upgrade your version of Fusion as you go. For example, if you are running Fusion version 4.1.9 on CentOS 7, you will need to set up a RHEL 8 server with XI version 4.1.9. Then backup your XI from the CentOS7 machine and return to the RHEL8 machine. You can choose to stay with the RHEL8 machine, or you can continue migrating to CentOS Stream/RHEL 9. You can use the compatibility matrix in the documents below for assistance. Make sure you perform the upgrades on a test instance so that you do not disrupt your production environment. Contact your Customer Success Manager (csm@nagios.com) for a temporary trial key and a temporary increase in allowed activations.

Finalizing the Migration

Once everything is working as expected on your new/test system, you can re-IP this machine IP and replace your existing production system. Also, to ensure your license is updated properly, reach back out to your Customer Success Manager (csm@nagios.com) to activate your new IP and retire your old production IP.

Supporting Documentation

Check out some of the relevant documents that will assist you through the process below:

Please note: Nagios will be able to assist you with problems and functionality directly related to the Nagios software itself. Since there are many variables within our customers’ environments, Nagios will not be able to offer implementation (including upgrades) or design solutions, other than the documents and steps we have supplied above.

Support and Additional Assistance

If you do need assistance upgrading your OS, design, or implementation, Nagios has a network of global partners who offer their services to assist with your effort. Please contact your Customer Success Manager (csm@nagios.com) and they will be able to assist you with finding a partner aligned with your needs.

Additional information about Nagios Fusion can be found here.