Agent Receiver Stopped! TLS issue?

CMK version: 2.3..0p28
OS version:Ubuntu 24.04 LTS

**Error message:partially running, stopped services: agent-receiver

Hi Folks,

I recently installed Checkmk on Ubuntu and added the Ubuntu as one of the hosts. Under the Monitor (services) section of this host, I see the error message I shared above. Also, when I installed/started the services, it said that my connection is not secure so need to register the host to the server, which I tried however unable to get it working. This is what I see, when trying to register:


sudo cmk-agent-ctl register --server x.x.x.x:8000 --site test --user testuser --hostname Ubuntu-test
Attempting to register at x.x.x.x, port 8000. Server certificate details:

ERROR [cmk_agent_ctl] the handshake failed: error:0A0000C6:SSL routines:tls_get_more_records:packet length too long:ssl/record/methods/tls_common.c:654:, error:0A000139:SSL routines::record layer failure:ssl/record/rec_layer_s3.c:645:

Caused by:
0: error:0A0000C6:SSL routines:tls_get_more_records:packet length too long:ssl/record/methods/tls_common.c:654:, error:0A000139:SSL routines::record layer failure:ssl/record/rec_layer_s3.c:645:
1: error:0A0000C6:SSL routines:tls_get_more_records:packet length too long:ssl/record/methods/tls_common.c:654:, error:0A000139:SSL routines::record layer failure:ssl/record/rec_layer_s3.c:645:


Status of my site:

agent-receiver: stopped
mkeventd: running
rrdcached: running
npcd: running
nagios: running
apache: running
redis: running
crontab: running

Overall state: partially running

The configuration .json file for registered host has no value and is kind of empty.

I would appreciate if someone could let me know what I could be missing here and what else I can try.

Please let me know if you need any more outputs.

Thank you for your help.

Regards,
Nick

1 Like

Please check if the port 8000 is listening, I had a similar issue and the cause was that another application was already using it. I changed it to 9000 and the problem was solved.

2 Likes

That seems to be the case, indeed. Just changed it to another port and it registered just fine! Thanks a lot for the quick help :slight_smile:

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Now, for windows host it seems to be saying that I have the wrong password for ā€˜agent-registration’ user. It’s the same one I used for Ubuntu machine and it worked! Anything different I need to do for Windows?

This was resolved by using the ā€˜automation’ user with right permissions. Not sure why the other one didn’t work which is meant for the Agent Registration purpose.

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I don’t reccommend using automation account for that as it contains a lot of not needed permissions.

Try to follow this article:
https://checkmk.atlassian.net/wiki/spaces/KB/pages/9471681/Agent+registration+role

In our environment I have two different users, one for registration and other for automatic updates.

2 Likes