Proxmox locking up


New Member
Oct 10, 2017
I have a Proxmox setup and am having an issue with it locking up every so often. Sometimes is can be weeks, other times just a few days. The GUI and local terminal (still displaying the login screen) become unresponsive and any containers or VMs stop working. A hard reset is the only way to get it going again.

Some time ago when it locked up, the terminal screen was full of lines "NMI watchdog: BUG: soft lockup - CPUx stuck for 22s!" but these days it just displays the login text.

I do keep Proxmox and the VMs updated on a fairly regular basis. The current Proxmox version is 5.4-5

Keep in mind that I have limited knowledge of VMs and a "bit more than basic" understanding of Linux. What logs should I be checking and what info is required to help me work out what is going wrong?
Some hardware info if it helps:
  • AMD AM4 Ryzen 7 1700 Eight Core 3.0GHz 65W CPU
  • ASUS AM4 ATX Prime X370-PRO Motherboard
  • DDR4 32GB (2x 16GB) Corsair 2666MHz Vengeance LPX Black RAM
  • (2x) 4TB Seagate 3.5" 6900PRM SATA IronWolf NAS HDD ST4000VN008
  • ASUS GT710 1GB PCIe Video Card 710-1-SL-BRK
  • StarTech 4 Port PCIe 2.0 SATA III RAID Controller Card
  • ASUS 24x DRW-24D5MT DVD Writer
  • TP-Link TG-3488 PCIe Gigabit LAN Card
Are you running Proxmox on ZFS?

I had issues with this where when I did large writes (such as running a backup) it would hang and require a hard reboot. When I removed the swap (didn't need it anyway, it was barely used), the hanging went away.

As a new user I can't post links but Google for
HOWTO use a zvol as a swap device
to find the wiki that has a section and link to a bug related to this.
I'm not sure what logs to look at and what to look for in them to try and track down this issue. Any clues please?


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