Lost Network connection

Infos:

  • Used Zammad version: 5.0.x
  • Used Zammad installation type: package
  • Operating system: Debian 10
  • Browser + version: Chrome Version 96.0.4664.45

Expected behavior:

  • Zammad should work normally

Actual behavior:

  • after 5-10 minutes the message appears: “network connection lost” " trying to reconnect" and only after a few minutes my Server is reachable again via http

Steps to reproduce the behavior:

  1. Installing my Debian 10 + apache2 mariadb and elasticsearch
  2. Enable apache2, mariadb…
  3. All the above tools are active before and during the failure!!! (systemctl status …)
  4. Connection via http in the web browser
  5. After some time the message “Lost network connection” appears and Zammad (!) is no longer reachable
    → I can ping my Debian without any problems
    → I can access via SSH

on the Internet you can find generally nothing about this problem!

Server Infos:
16 GB RAM
16 GB Hard disk space
8 CPUs

Does anyone know what this could be and how to solve it?