Checkmk Raw Edition: Monitoring That Stays Out of the Way Until You Need It
If you’ve ever looked at Nagios and thought, “this could be easier,” you’re not alone. Checkmk Raw Edition takes the core of Nagios — its speed and plugin ecosystem — and wraps it in a saner, more usable interface. No magic. No vendor lock-in. Just solid monitoring that works.
What It Actually Is
Checkmk Raw Edition is an open-source infrastructure and application monitoring system, built around Nagios but without the headaches. You still get the Nagios engine under the hood, but with a much more intuitive web UI, automatic service discovery, and a huge library of plugins and checks.
It runs on Linux, comes with its own web interface (Multisite), and supports everything from SNMP to SSH to agents — plus APIs, graphs, notifications, and custom checks.
Think of it as Nagios, but modern and actually manageable.
Where It Works Best
– Mid-sized networks with Linux, Windows, switches, and cloud mixed together
– Admin teams who want visibility but aren’t ready for full-blown Prometheus+Grafana stacks
– Shops currently using Nagios or Icinga that want an upgrade without rewriting everything
– Test labs, on-prem setups, or air-gapped environments
It scales better than you’d expect — especially for a free edition.
What Makes It Useful
Feature | Why It Matters |
Nagios Core | Uses tried-and-true Nagios engine under the hood |
Web UI (Multisite) | No more editing text files to see graphs |
Auto-Discovery | Detects services and hosts — no manual check configs |
Hundreds of Check Plugins | Disk, memory, load, UPS, Docker, certificates… |
Notifications | Built-in alerting via email, script, webhook, etc. |
Performance Graphs | Integrated RRD/graphing with no extra setup |
Custom Dashboards | Drag-and-drop views of what matters |
Open Source & Free | GPL-licensed, community-supported, no timebombs |
What You’ll Need
– A Linux server (Debian, Ubuntu, RHEL, etc.)
– Python, Apache, and Nagios-core dependencies
– SSH or SNMP access to monitored hosts (or agents installed)
– Disk space — monitoring data can add up fast
– Some time to get used to its logic (but far less than raw Nagios)
Checkmk Raw runs as a single-site instance by default, which is more than enough for most setups.
How to Install (Short Version)
1. Download the RAW edition from the official site:
https://checkmk.com/download
2. Install the package:
sudo dpkg -i check-mk-raw-*.deb # Debian-based
3. Create a site:
omd create mysite
omd start mysite
4. Login to the web UI:
http://your-server/mysite/
Default user: cmkadmin
5. Add hosts, auto-discover services, and tune thresholds. You’re monitoring.
What Admins Say
“It’s like Nagios but 100x easier to maintain. No text file juggling.”
“I had it showing graphs and alerts in 30 minutes. That alone makes it worth using.”
“Still runs on Debian 10 just fine. We use it to monitor a mix of old hardware and new cloud VMs.”
A Note on the “Raw” Part
Checkmk also has commercial editions with more dashboards, APIs, and integrations. Raw Edition skips those — but keeps the core features intact. If you’re okay with CLI and manual tuning, you won’t feel limited.
And hey — it’s open-source. If something bothers you, you can patch it.