Antivirus exclusions for Checkmk agents and servers

Antivirus software sometimes interferes with Checkmk monitoring. This article explains how to add exclusions to prevent that.

LAST TESTED ON CHECKMK 2.2.0P1

Table of Contents

Although this article gives guidance on how to avoid interference of Antivirus software with Checkmk, we cannot guarantee that it will work.
We can only help you on a best-effort basis, as Antivirus software these days sometimes behaves in unpredictable ways and uses methods that are hard to track and understand.
Especially, but not exclusively on a Checkmk server, there will be no support for Antivirus.

Problem

You intend to run an Antivirus solution on your Checkmk server or a host running the Checkmk agent.

Solution

To reduce issues with the antivirus software interfering with Checkmk, the files, and folders below must be excluded from being scanned.
However, depending on the mechanisms of your Antivirus solution, not only files and folders might be targeted.
As said above: We cannot and will not guarantee that with the exclusions below, you will have no trouble at all with your Antivirus.

Checkmk Server

Exclude the below folders on the Checkmk server:

/opt/omd/apache/
/opt/omd/sites/
/opt/omd/versions/
/omd/

Checkmk Linux Agent

Exclude the below files and directories on the monitored Linux nodes:

/usr/bin/check_mk_agent
/usr/bin/check_mk_caching_agent
/usr/lib/check_mk_agent/
/var/lib/check_mk_agent
/var/lib/cmk-agent
/etc/check_mk

You can find a detailed listing of relevant files here: https://docs.checkmk.com/latest/en/agent_linux.html#_paths_on_the_monitored_host

Checkmk Windows Agent

Exclude the below directories on the monitored Windows nodes:

C:\Program Files (x86)\checkmk\
C:\ProgramData\checkmk\

You can find a detailed listing of relevant files here: https://docs.checkmk.com/latest/en/agent_windows.html#_paths_on_the_monitored_host

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