[SOLVED] VM will not start after backup restore

[lanceh]

Hi Folks,

Strange happenings - typically backup restores have worked perfectly but for some reason, this VM failed to boot after restore.

I restored from several timed backups but the same result - no boot.

Any ideas?

start failed: command '/usr/bin/kvm -id 110 -name ML-01 -no-shutdown -chardev 'socket,id=qmp,path=/var/run/qemu-server/110.qmp,server=on,wait=off' -mon 'chardev=qmp,mode=control' -chardev 'socket,id=qmp-event,path=/var/run/qmeventd.sock,reconnect=5' -mon 'chardev=qmp-event,mode=control' -pidfile /var/run/qemu-server/110.pid -daemonize -smbios 'type=1,uuid=1bd11cbd-da0c-4f6c-9e22-d76b348959f3' -smp '10,sockets=1,cores=10,maxcpus=10' -nodefaults -boot 'menu=on,strict=on,reboot-timeout=1000,splash=/usr/share/qemu-server/bootsplash.jpg' -vnc 'unix:/var/run/qemu-server/110.vnc,password=on' -cpu host,+kvm_pv_eoi,+kvm_pv_unhalt -m 14336 -device 'pci-bridge,id=pci.1,chassis_nr=1,bus=pci.0,addr=0x1e' -device 'pci-bridge,id=pci.2,chassis_nr=2,bus=pci.0,addr=0x1f' -device 'vmgenid,guid=898c2970-9a7f-4119-bc72-578b087fee89' -device 'piix3-usb-uhci,id=uhci,bus=pci.0,addr=0x1.0x2' -device 'usb-tablet,id=tablet,bus=uhci.0,port=1' -device 'vfio-pci,host=0000:02:00.0,id=hostpci0,bus=pci.0,addr=0x10' -device 'VGA,id=vga,bus=pci.0,addr=0x2' -device 'virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3' -iscsi 'initiator-name=iqn.1993-08.org.debian:01:559538e2a0f2' -drive 'file=/zfsdata/template/iso/ubuntu-20.04.4-live-server-amd64.iso,if=none,id=drive-ide2,media=cdrom,aio=io_uring' -device 'ide-cd,bus=ide.1,unit=0,drive=drive-ide2,id=ide2,bootindex=101' -drive 'file=/dev/zvol/ZFS01-SPIN/vm-110-disk-0,if=none,id=drive-virtio0,format=raw,cache=none,aio=io_uring,detect-zeroes=on' -device 'virtio-blk-pci,drive=drive-virtio0,id=virtio0,bus=pci.0,addr=0xa,bootindex=100' -netdev 'type=tap,id=net0,ifname=tap110i0,script=/var/lib/qemu-server/pve-bridge,downscript=/var/lib/qemu-server/pve-bridgedown,vhost=on' -device 'virtio-net-pci,mac=8E:AA:C3:84:C7:3B,netdev=net0,bus=pci.0,addr=0x12,id=net0,bootindex=102' -machine 'type=pc+pve0'' failed: got timeout

 

[lanceh]

After trying all sorts of ideas - it was the NVidia GPU passthrough that was crashing the VM.

All looked good as far as the IOMMU Groups and other settings but the VM would not boot.

If you have this issue first remove the PCI GPU in the hardware setting and reboot.

If the VM reboots without the GPU then reboot the whole server proxmox server to fix the issue.

No idea why a reboot works - might be memory mapping issues that appear over time when creating and deleting VM's.

 

[leesteken]

If a device does not reset properly, your will need to reboot the host before the passthrough will work again.
If you are getting timeouts when starting the VM, it is usually not enough free (unfragmented) memory to pin all the VM memory into actual RAM, which is needed because of the passthrough and the fact that PCI devices can do DMA at any time to any part of the memory.

 

[Brandito]

After trying all sorts of ideas - it was the NVidia GPU passthrough that was crashing the VM.

All looked good as far as the IOMMU Groups and other settings but the VM would not boot.

If you have this issue first remove the PCI GPU in the hardware setting and reboot.

If the VM reboots without the GPU then reboot the whole server proxmox server to fix the issue.

No idea why a reboot works - might be memory mapping issues that appear over time when creating and deleting VM's.

Thanks for this, I had the same exact issue. Feels like a bug