Zabbix. Where can I see what happened to the Zabbix server?

Question

Zabbix

Zabbix 4.4 is running on Ubuntu server 18.04. A lot of character letters came to the mail at night:
Host: Qtech 4610-52T
Item: PingVal
Key: icmppingsec[,3]
State: Not supported

Here are some graphs showing that there was a problem.



The Ubuntu syslog is empty at this time.

Where else can you see what happened?

Answer 1

Solution to the problem: lack of disk space under the OS, expanded the disk (it is on a virtual machine) and the problem did not arise anymore.