Unscheduled System Reboot

[csax]

Hello Everybody

I am running TrueNAS-12.0-U4.1 and noticed some unscheduled and unexpected system reboots every now and then. I started to see this issue with 12U1 already. At that point it happened very rarely and I did not bothered about it. However, I see those reboots more frequent these days and thus had a look in the logs but did not find anything except a reboot out of the blue...

Jul 31 00:51:34 SAXNAS03 kernel: lo0: link state changed to UP
Jul 31 00:54:35 SAXNAS03 kernel: in6_purgeaddr: err=65, destination address delete failed
Jul 31 02:53:51 SAXNAS03 syslog-ng[3764]: syslog-ng starting up; version='3.29.1'
Jul 31 02:53:51 SAXNAS03 ---<<BOOT>>---

Does anybody else see such behavior as well?
Is there a way to get more detailed logging? I have the option "System/General/Other Options/Crash Reporting" checked. I have set the syslog settings in "System/Advanced" set to debug and checked "enabled kernel debug". Does this do any good to get more detailed login? Would you recommend some additional measures to get to the bottom of these unscheduled system reboots?

Any help is much appreciated!
Regards
Chris

 

[HarambeLives]

Are you on a UPS?

 

[csax]

The issue occurs with and without ups. I have also monitored voltage and power changes. However, there is not even a small glitch.
It seems to happen only when there is long and extensive disk usage. However, that is just a guess since I am not always right next to the server when it happens.
Any chance one can see more of the activity that is going on in the logs?
I also operate a windows server with similar config and very busy disks but never happened there. Recently I even switched the msi controllers between the servers but no change.
This now happens about every two to three days