CMK version: 2.0.0p33
OS version: CentOS 8
Error message: We have some HTTPS Active Check that are in OK status into “Services of host” but in the Monitor tab they are in WARN status and in Summary there is (null).
In the nagios.log it’s logged as:
WARNING;HARD;2;(null)
Can you provide screenshots of both of the Views? And if you hide the service name, it’s hard to say if that even are the same services you are comparing 
.
If this happens after a core restart / activation of changes then
it is a known problem with 2.0 and Nagios core and active checks.
See here Checkmk Service (null) Returns On Many Servers
It happens only on active checks like check_http or the CheckMK service.
Hi Andreas, thanks for your answer, but I have installed also the 2.1.0 raw edition version and I have the same behavior.
In the Setup view I have OK in the Status and in the Monitor view I have always a WARN State with (null) in the summary.
In the ~/var/nagios/nagios.log I have this (sorry for the many canceled lines):
The Active Check is a POST with an HTTP POST data (xml) that contains 812 characters, is it possible that it is too big and for this we obtain (null) in summary of monitor tab?
I resolved my problem modifing the Content-Type header of the request from “text/xml;charset=utf-8” to “text/xml”, so is it possible to know why the entry charset=utf-8 produces this issue?
Thanks
