How to install Checkmk on Ubuntu

Installing Checkmk on Ubuntu prepares a Linux server to host one or more OMD monitoring sites. Use the Ubuntu package path when the monitoring server should run directly on a VM or bare-metal host instead of in the official Checkmk container.

The Checkmk download page provides a separate .deb file for each supported Ubuntu release, Checkmk edition, version, and CPU architecture. Checkmk server packages are built for x86_64 systems, so the package file must match both the Ubuntu release codename and the server architecture.

A package install adds the Checkmk software version under /omd/versions and installs the omd management command. Create a site after installation before opening the web UI, adding hosts, or handing the server to monitoring operators.

1. Open a terminal with sudo privileges.
2. Check the Ubuntu release.

   $ cat /etc/os-release
   PRETTY_NAME="Ubuntu 26.04 LTS"
   NAME="Ubuntu"
   VERSION_ID="26.04"
   VERSION_CODENAME=resolute
   ##### snipped #####

   Use the package suffix that matches the release codename. Package suffix examples include resolute for Ubuntu 26.04, noble for Ubuntu 24.04, and jammy for Ubuntu 22.04.

3. Check the CPU architecture.

   $ uname -m
   x86_64

   The Checkmk server package is for x86_64 Ubuntu systems. Use a supported x86_64 Ubuntu server or a Checkmk appliance if this command returns aarch64 or arm64.

4. Confirm that the Ubuntu package sources include main and universe.

   $ cat /etc/apt/sources.list.d/ubuntu.sources
   Types: deb
   URIs: http://archive.ubuntu.com/ubuntu/
   Suites: resolute resolute-updates
   Components: main universe
   
   Types: deb
   URIs: http://security.ubuntu.com/ubuntu/
   Suites: resolute-security
   Components: main universe
   ##### snipped #####

   On Ubuntu 22.04, this information may be in /etc/apt/sources.list. Add the universe and security repositories before installing Checkmk dependencies if they are missing.

5. Refresh the package index.

   $ sudo apt update
   Hit:1 http://archive.ubuntu.com/ubuntu resolute InRelease
   Get:2 http://archive.ubuntu.com/ubuntu resolute-updates InRelease [137 kB]
   Get:3 http://security.ubuntu.com/ubuntu resolute-security InRelease [137 kB]
   Reading package lists... Done

6. Install the download and signature tools.

   $ sudo apt install --assume-yes ca-certificates curl gnupg
   Reading package lists... Done
   Building dependency tree... Done
   Reading state information... Done
   ca-certificates is already the newest version.
   curl is already the newest version.
   gnupg is already the newest version.

7. Download the matching Checkmk Community package.

   $ curl --location --fail --output /tmp/check-mk-community-2.5.0p7_0.resolute_amd64.deb https://download.checkmk.com/checkmk/2.5.0p7/check-mk-community-2.5.0p7_0.resolute_amd64.deb

   Replace the version, codename, and edition in the file name with the package selected from the official Checkmk download page when a newer patch release or a commercial edition is required.

8. Download the Checkmk release signing key.

   $ curl --location --output /tmp/Check_MK-pubkey.gpg https://download.checkmk.com/checkmk/Check_MK-pubkey.gpg

9. Import the signing key for package verification.

   $ gpg --import /tmp/Check_MK-pubkey.gpg
   gpg: key 434DAC48C4503261: public key "Check_MK Software Release Signing Key (2018) <feedback@check-mk.org>" imported
   gpg: Total number processed: 1
   gpg:               imported: 1

10. Verify the downloaded package signature.

    $ gpg --verify /tmp/check-mk-community-2.5.0p7_0.resolute_amd64.deb
    gpg: Signature made Thu Jun 18 11:13:19 2026 UTC
    gpg:                using RSA key B1E7106575B723F00611C612434DAC48C4503261
    gpg: Good signature from "Check_MK Software Release Signing Key (2018) <feedback@check-mk.org>" [unknown]
    gpg: WARNING: This key is not certified with a trusted signature!
    Primary key fingerprint: B1E7 1065 75B7 23F0 0611  C612 434D AC48 C450 3261

    The Good signature line confirms that the package was signed by the imported Checkmk release key. The trust warning only means the local GPG keyring has not personally certified that public key.

11. Install the Checkmk package with APT.

    $ sudo apt install /tmp/check-mk-community-2.5.0p7_0.resolute_amd64.deb
    Reading package lists... Done
    Building dependency tree... Done
    Reading state information... Done
    The following NEW packages will be installed:
      check-mk-community-2.5.0p7
    ##### snipped #####
    Setting up check-mk-community-2.5.0p7 (0.resolute) ...

    APT installs the required Ubuntu dependencies, including Apache, PHP, cron, xinetd, and other packages used by Checkmk sites.

12. Confirm that omd reports the installed Checkmk version.

    $ omd version
    OMD - Open Monitoring Distribution Version 2.5.0p7.community

13. List the installed Checkmk versions.

    $ omd versions
    2.5.0p7.community (default)

    The default version is used when a new site is created without selecting a different installed version.

14. Create the first Checkmk monitoring site before opening the web UI.

    Related: How to create a Checkmk monitoring site