Fix Proxmox (PVE) “can’t lock file ‘/var/lock/qemu-server/lock-xxx.conf’ – got timeout” (Proxmox can’t shutdown/stop virtual machine) (Proxmox kill/force stop virtual machine)

The Issue

When trying to “Stop” or “Shutdown” virtual machine from Proxmox (PVE) web gui, the “Cluster log” shows

end task UPID:pve:xxxxxxxx:xxxxxxxx:xxxxxxx:qmstop:xxx:root@pam: can’t lock file ‘/var/lock/qemu-server/lock-xxx.conf’ -got timeout
end task UPID:pve:xxxxxxxx:xxxxxxxx:xxxxxxx:qmreboot:xxx:root@pam: VM quit/powerdown failed

The Fix

We can manually delete the lock from following path

/run/lock/qemu-server

# The file will be
/run/lock/qemu-server/lock-100.conf
/run/lock/qemu-server/lock-102.conf
...

Make sure only delete the correct one!

You can also do it using script from this site-

https://dannyda.com/2020/05/11/how-to-fix-proxmox-pve-cant-lock-file-var-lock-qemu-server-lock-xxx-conf-got-timeout-proxmox-cant-shutdown-virtual-machine/