Checkmk is described as 'Monitoring tool of servers, applications, networks, cloud, containers, storage, databases, IoT and more. Checkmk is available as Raw Edition, which is 100% pure open source, and as Enterprise Edition with a lot of additional features' and is a Network Monitor in the network & admin category. There are more than 25 alternatives to Checkmk for a variety of platforms, including Linux, Web-based, Windows, SaaS and Self-Hosted apps. The best Checkmk alternative is Zabbix, which is both free and Open Source. Other great apps like Checkmk are Nagios, Datadog, Spiceworks and HyperDX.