ESXi 6.7U2 Host - freeze and not responsive

Hi Community,

I have an ESXi Host that suddenly froze 2 days ago without apparent reason.

See attachment for error message.

There was no hardware failure.

I had to reboot the server and the host is running normally now.

I need to find the reason of the failure.

Is there something in the error message I can go by?

What log files should I check to find a more descriptive error message?

Thank you.