[SOLVED] Backup of VM with a virtual USB device


Oct 10, 2021
Hello all!
I have a VM that has this device in the config:
args: -device 'nec-usb-xhci,id=usb-bus0,multifunction=on' -drive 'file=/var/lib/vz/images/101/usb.img,media=disk,format=raw,if=none,id=drive-disk-bootloader' -device 'usb-storage,bus=usb-bus0.0,port=1,drive=drive-disk-bootloader,id=usb-disk-bootloader,bootindex=999,removable=on'

If I make a backup of the VM using the web gui the usb.img file is not in backup (the backup file is like 600 bytes in size). How can I change that?
you can't, since PVE doesn't know about this device/drive/image.
Is there a way to:
a) let the pve know about the file with some sort of "additional file" flag
b) move the usb drive definition from the args section to the base config to achieve the same thing and inform the system about the disk image in the process?
Thanks for the info.
That's the suggested by the community way to add a bootable usb to a Xpenology VM.
maybe it's possible to find a way to let it boot from a regular disk? seems like a weird restriction ;) but I have no experience with it whatsoever..
Looks like the only workaround is to make a dummy (always powered off) VM with that image file added as a disk and schedule a backup of that too, I was also thinking about an unused disk but I guess unused disks are ignored when backing up.
After some messing around I've used Automated Redpill Loader in proxmox with a "SATA" disk. The loader identified it as a DOM disk and successfully loaded. Backups of a SATA disk work as normal.
Yes, it's a workaround not a solution.


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