Hello.  I'm on 6.8.3 and have been having clean shutdowns randomly.  They have occurred as soon as 7-8 days uptime to upwards of 30 days.  Can't seem to figure out the cause other than there typically is a root login by me sometime earlier in the day (though that is not unusual by any means). 

 

Attaching the log in the peri-shutdown period and diagnostics files.

 

Any thoughts would be greatly appreciated.

syslog-192.168.0.10.log serverprime-diagnostics-20200724-1744.zip

Have you done memtest?

Also, do you have any pets or children who might be 'swatting' at the power switch?  (A quick push of the power switch will start a clean shutdown.)  Cats seem to be the prime suspect for this kind of activity.

I have not done memtest, but my understanding was that ECC ram would not necessarily show an issue?  Can give it a shot if it would prove valuable.

 

Do have both kids and cats, but the button is recessed.  Good point though.  May tape a piece of cardboard over it and see if it changes.