Report - Error reading from remote server

CMK version: Checkmk Managed Services Edition v2.4.0p16
OS version: Checkmk Appliance v1.7.13

Error message:
Proxy Error

The proxy server received an invalid response from an upstream server.
The proxy server could not handle the request

Reason: Error reading from remote server

Output of “cmk --debug -vvn hostname”: (If it is a problem with checks or plugins)

Hello Community,

after updating from v2.3 to 2.4.0p16, I am having a problem with a report that times out. Error message as mentioned above. The access log on the central server shows the following:

[Mon Dec 01 15:11:00.221651 2025] [proxy:error] [pid 2171460:tid 2171460] [client x.x.x.x:60590] AH00898: Error reading from remote server returned by /sitename/check_mk/report.py, referer: https:// url-to-report

[Mon Dec 01 15:11:00.221599 2025] [proxy_http:error] [pid 2171460:tid 2171460] (70007)The timeout specified has expired: [client x.x.x.x:60590] AH01102: error reading status line from remote server 127.0.0.1:5000, referer:  https:// url-to-report

This report is a report from a satellite with many graphs for a period of one week.
Other reports from the satellite work, and if I reduce the time period and hosts for the affected report, it works also.

Where and how can I increase the timeout for the reports on the remote instances?

Thanks in advance.
Best regards,
Marc

Does anyone else have a suggestion?

I have already changed the timeout in the apache.conf of the target site and restarted Apache, but that had no effect.

The report scheduler is also no longer sending the reports.

Surely it must be possible to increase the timeout for the reports somehow?