I have assembled my desktop PC about 2 years ago. It’s fairly beefy (AMD Ryzen 9 3950X 16-Core Processor, 128Go RAM, nVidia RTX 3080 Ti). It’s running debian stable.
Once in a while (not that often, but like every 2 weeks or so), seemingly at random times, not especially under heavy loads, the system crash and freeze, irresponsive to even the linux sysrq magic keys. I never manage to find what was the cause. One interesting fact is that when it happens, for some reason it seems to “freeze my network” too, ie, other (ethernet) devices on my local network have no connectivity anymore. They’re all connected to the same router, but not through this crashing PC. Connectivity comes back as soon as I force shutdown the crashing PC.
What can cause this and how could I fix these freezes?
I can only offer some additional troubleshooting steps.
https://wiki.debian.org/NetworkManager#Wired_Networks_are_Unmanaged
NOTE: Unless you know networking, this is probably going to take you down a networking rabbit hole, so glhf.
Some Debian references regarding networking and different configurations:
https://www.debian.org/doc/manuals/debian-reference/ch05.en.html
https://www.debian.org/doc/manuals/debian-handbook/sect.network-config
If you want to stick with NM, it seems you can change the logging level to see if you get more details. I would check the man page or documentation for NM for instructions for debugging. I would expect that you can disable interfaces in NM to reduce the likelihood of some fringe case that is plaguing your setup. Since I don’t run NM, I can’t provide any detailed suggestions.
More of a question but is the switch or router also the same device for the last 2 years? Is it possible that the network device is misbehaving and causing the desktop to lock up? This would feed into @0v0 request to wireshark/tcpdump from a laptop or other device connected to the router/switch to see what’s going on traffic wise.