Every organization needs monitoring to make sure that servers, networks, applications, cloud assets, and other elements work as they should. Monitoring also provides timely alerts, and it helps IT teams track down the causes of (potential) problems. Having a suitable monitoring tool will help you resolve problems faster, ideally before they have an impact on operational systems. Checkmk [1] is an open source monitoring tool that is ideally suited for modern hybrid environments, combining enterprise-grade scalability and security with the extendibility of open source software.

In most cases, Checkmk runs on a dedicated server or virtual machine (VM). As I am just running a small monitoring setup for my home office environment, my host will be my computer with Ubuntu 18.04. The computer has four CPU cores and 4GB of RAM, which is more than enough to get started. Checkmk also runs on other Linux distributions, such as Debian, Red Hat Enterprise Linux, CentOS, or SUSE Linux Enterprise Server, and you can also run Checkmk on a Docker container or virtual appliance. If you install Checkmk on a dedicated host, the only additional steps you need are transferring the files to the server.

Checkmk can monitor anything with an IP address, including servers, cloud assets, and network devices, as well as systems that belong to the Internet of Things (IoT). For this article, I chose to monitor my TP-Link router. Checkmk also comes ready-equipped with reasonable thresholds for alerts. These pre-configured thresholds will come in handy, because your monitoring will be up and running within a few minutes without you having to worry about setting up alerts.

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