I have a production 2012R2 virtualized server (previously Xenserver, migrated to xcp-ng, 8.0 currently) that has been running fine for 4 years. Recently, the system tried to update Xen drivers and it failed, making the server sloooow and unusable. I was advised to migrate Xen drivers to XCP-np drivers as my system was not accepting Xen Drivers anymore. This worked and the system was again up and running fast. Nevertheless, I have been experiencing sudden reboots (once per day or couple of days) but cannot find any clue on the system logs to what is causing it. The last event I can find when the shutdown happened is 7036 related to VSS but this seems to be a normal event in the service life.
EDIT: Does not seem to be related to VSS as another reboot is preceded by a different service message (that, by the way, look a normal life event of service started/service stopped).
How can I debug the problem down to its root to find out what is causing it?
