Checkmk monitoring for servers, VMs and networks
Checkmk tells you what is failing in your infrastructure before your users do. inett builds the monitoring and tunes it so that an alert means something.
The problem
Without monitoring, the first sign of trouble is a user on the phone: a full disk, an expired certificate, a backup job that has failed for a week. Where monitoring exists, it often fails in the other direction. It sends so many emails that people filter them into a folder nobody opens.
A second common pattern is the hand-maintained Nagios server. Its configuration lives in text files that one person understands, and new servers only appear in it when someone remembers to add them.
What inett does
We install Checkmk and bring your systems into it. On each host, Checkmk discovers the services it can check, such as file systems, network interfaces, processes and databases. Together with your team we decide which of these matter and at which thresholds an alert is worth sending.
Next comes the question of who gets told what, and when. A firewall outage should reach different people than a full disk on a test VM. Checkmk applies rules to groups of hosts through folders and labels, so you do not configure each server by hand.
For Proxmox VE and Ceph we use the checks that ship with Checkmk. Switches, storage systems and an OPNsense firewall are polled via SNMP or their APIs. We finish with training, so your administrators can add hosts and adjust rules themselves. If you would rather hand over day-to-day operation, we cover that through our managed services.
Technical details
- Current version
- Checkmk 2.5 (as of October 2026)
- Editions
- Checkmk Community (open source, formerly “Raw”), Checkmk Pro (formerly “Enterprise”), Checkmk Ultimate (formerly “Cloud”), Checkmk Ultimate with Multi-Tenancy (formerly “Managed Services”); renamed from version 2.4.0p24 in late 2025
- Edition differences
- Community uses Nagios as its core; Pro and Ultimate use the Checkmk Micro Core and add the agent bakery, reporting and vendor support; Ultimate adds cloud checks, push agents and OpenTelemetry
- Data sources
- Checkmk agent for Linux, Windows and other systems; SNMP for network devices; special agents for APIs such as Proxmox VE or VMware vSphere
- Server platform
- Linux distributions such as Debian, Ubuntu, Red Hat Enterprise Linux or SLES, or the Checkmk appliance
- Larger estates
- distributed monitoring across several sites with a central view
- Notifications
- email, plus integrations with chat, ticketing and on-call tools
- Management
- web interface and REST API
- Documentation
- docs.checkmk.com
What is included
- Choice of edition and design of the monitoring sites
- Installation of the Checkmk server
- Agent roll-out on Linux and Windows hosts
- Integration of Proxmox VE, Ceph, storage and network devices
- Threshold tuning so that alerts are relevant
- Notification rules by team, service and time of day
- Migration from an existing Nagios or Checkmk installation
- Training for your team and documentation of the rule set
- Updates and maintenance of the monitoring once live
If you need licences for Checkmk Pro or Ultimate, our sister company inett GmbH can handle the purchase.
Who it is for
Checkmk fits organisations that want one view of servers, virtual machines and network, with the monitoring maintained by their own team or by us. Smaller environments often get by with Checkmk Community. Several locations, reports or vendor support usually point to Pro.
It is less suited to development teams who mainly need application metrics and dashboards per release. Prometheus with Grafana is usually closer to that workflow. Checkmk can ingest such data, but its focus is infrastructure.
Frequently asked questions
Is Checkmk free?
Checkmk Community is open source and free of charge. Pro, Ultimate and Ultimate with Multi-Tenancy require a subscription. The vendor offers a 30-day trial.
What happened to the Raw Edition?
Since late 2025 it is called Checkmk Community. The rename did not change its features or licence.
Can we keep our Nagios configuration?
Not as it stands. Checkmk rediscovers the services on each host. During the migration we translate your thresholds and contact groups into Checkmk rules.