Windows agent not listening on 6556

CMK version: 2.1.0p17
OS version: server 2012/2022

Hi we recently started implementing corporate mandated GPOs. It works fine on 99% of the servers but on a few the checkmk stop listening.
I tried full clean reinstall and unless I remove the policy it just won’t listen (nothing on 6556 on netstat).

How can I approach this issue? I tried looking at the logs but honestly I don’t know what to look for.

If anyone can assist I will be greatful,

Ben

Hi

  1. Windows or Linux Server ???
  2. FW in the Network ??? State can checked via NMAP from Monitoring Server
root@deksmoni:~# nmap -p6556 10.xx.xx.xx
Starting Nmap 7.70 ( https://nmap.org ) at 2023-02-28 09:19 CET
Nmap scan report for HOST
Host is up (0.00016s latency).

PORT     STATE SERVICE
6556/tcp open  unknown
MAC Address:  (Unknown)

Nmap done: 1 IP address (1 host up) scanned in 0.69 seconds
  1. local FW ???
  1. I wrote windows in the title and OS 2012\2022…
  2. It’s not even a network issue, its local on the server. the agent listener is simply not running (server FW is off).

Thanks

take a look:

Chapter 5

then check from Monitoring Server

OMD[mysite]:~$ cmk -d ourHost

Somtimes … its good sometimes its … not so good :wink: … where are my classes ???