Questions about disposable sys-usb VM (USB keyboard & no-strict-reset)

User Support
1

Hello!

I’m trying to follow the DisposableVM Customization documentation to create disposable sys-* VMs. The disposable sys-net and sys-firewall is working fine, but there is some question about the disposable sys-usb:

  1. If i reach the " Starting the DisposableVMs" point in the documentation i’m not sure how to detach the USB controller form the original sys-usb and start the disposable sys-usb if i have a USB keyboard. Because if i think right when i want to stop sys-usb to detach the USB controller than i won’t be able to use neither my keyboard or mouse. Is there some way i could make this change?

  2. If the no-strict-reset=True is set in the original sys-usb i think i have to set it in the disposable sys-usb too. Is it right?

Thanks any help!

2

first: wear caution if you do not have a PS/2 port on your machine, because you can lock yourself out. It has happen to others :wink:

just in case: backup your important stuff and verify the backup (there is an option there to just check without restore)

check in the original sys-usb the controllers you have there. If you have more than one, you can detach one and attach it to your new disp-sys-usb.
at this point you will have 2 different sys-usb. if it works, you can probably take the other controllers and attach them to the disposable sys-usb (again check what controller is your keyboard plugged to)

regarding “no strict reset”, just play with it a little in your original sys-usb to get to know what you need. if possible do not enable it, but that is unlikely

3

Yeah, for the first time i wanted to create sys-usb with manually. Of course the result was a lock out… Fortunately this is a fresh install, so data loss is not a problem now. Now i think, that i should have made a disposable sys-usb instead of creating the default sys-usb.

I’ve forgot to mention that i have only 1 USB-controller. I had to enable my USB keyboard for login with the sudo qubesctl state.sls qvm.usb-keyboard command, i think that is why the no-strict-reset is enabled. The controller now is in the 2 USB VM, but because the original sys-usb is still running and provides USB accessibility to my keyboard and mouse, i don’t know how to switch to the disposable sys-usb.

4

In the meantime i’ve read how to remove a USB Qube. If i understand correctly this would be the same as switch between the normal sys-usb and disposable sys-usb, because i have to stop the USB Qube, so i would be in the same situation where the USB keyboard wouldn’t work, so i couldn’t edit the /etc/default/grub file.