Since early today, we are noticing that all zabbix server processes are crashing after being started for 5 minutes.

I have attached the logs to this issue so you can have a look at them. They seem to indicate that it is crashing during the calculation of trends. This happens every single time. We first had this issue with Zabbix 2.2.2 and upgraded a few hours ago to 2.2.3 to see if this would help. It has effectively not change anything.

The only change we have made today to our Zabbix server is the insertion of correct credentials (before this they were incorrect) of our second vCenter server. The first vCenter server has been functional for several months now. I don't know if this is relevant as well but this VM was turned off for a little over 12h for maintenance reasons.