Unable to register a fresh Windows agent

Troubleshooting
1

CMK version:
Checkmk Raw Edition 2.4.0p10

OS version:
Windows 10 Pro 22H2 19045.6216

Greetings,

I’m newcomer with CheckMK. My server part is installed on a docker container, with the following ports being mapped from the docker host (ubuntu VM) to the container itself:
- 5000:5000
- 8001:8000

I am unable to register my freshly installed Checkmk Windows agent. Here is the command I use:

.\cmk-agent-ctl.exe register --hostname workstationhostname --server 192.168.1.2:8001 --site http://192.168.1.2:5000 --user agent_registration --password "mypassword"

I access the webpage of the Checkmk console via http://192.168.1.2:5000 so my understanding is that I should put that URL as an argument. I have mapped port 8001 to the internal 8000 because I have another application sitting at this port already. I am not aware if that may be the problem.

Error message:

-----END CERTIFICATE-----

Issued by:
        Site 'cmk' local CA
Issued to:
        cmk
Validity:
        From XXX
        To   XXX

Do you want to establish this connection? [Y/n]
> y
[2025-08-26 10:49:45.467106 +03:00] ERROR [cmk_agent_ctl] cmk-agent-ctl\src\main.rs:35: Error registering existing host at https://192.168.1.2:8001/http://192.168.1.2:5000

Caused by:
    Request failed with code 404 Not Found: Not Found
PS C:\Program Files (x86)\checkmk\service>

I have not performed any FW changes on the Windows endpoint because from what I’ve seen, the agent should do that during installation anyway.

Any help would be appreciated.

2

The server and site you are using is wrong. Please read the docs:

best regards

Mike

4

When you created your site with omd you gave it a name: 'omd create mysite'.
The omd script then also tell you how to connect to the site:

The site can be started with omd start mysite.
 The default web UI is available at http://myhost/mysite/

for registration you use:

--server myhost --site mysite

Basically everything is well written in the docs.

best regards

Mike

6

Thank you again, Mike. Because I ran this via docker-compose, some of the (I think pretty much all?) initial configs are skipped, so I didn’t create any site in the first place. All I did was to run the container and logon to the console.

I placed the URL which my browser redirected me when I visit my instance: http://192.168[.]1.2:5000 > http://192.168[.]1.2:5000/cmk/check_mk. /cmk/check_mk didn’t worked out but just cmk did.

The agent was registered successfully. The checkmk AI chatbot (which was free to use!) also helped me.

I’m just a couple of hours into this product but so far I couldn’t be happier.