4.3: Disable minimal-usbvm service in sys-usb to use external storage

Community Guides
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Major note:

It turns out that this issue might not be intentional and real regression. The linked Github issue is to track the problem and solve it.

Original post

Hi.

  1. Click on Qubes Domains icon on the taskbar (the gray cube icon). Then from the running qube list select sys-usb and then Settings. Another alternative to open settings is going to App Menu → Cube icon → SERVICE tab → sys-usb → Settings at the bottom of the menu.
  2. In Settings: sys-usb dialog. Go to Services tab.
  3. If minimal-usbvm is there and is checked, un-check it.If it is not there, click Select a serice → (custom...) → Add → type minimal-usbvm and then unckeck it.
  4. Go back to Advanced tab and increase initial memory to 500.

Alternative solution if you like command line:

  1. Open a terminal in dom0
  2. type qvm-service sys-usb minimal-usbvm off
  3. type qvm-prefs sys-usb memory 500

That is it.

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Are you fine if I split this into a dedicated topic in Community Guides ?

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And restart sys-usb after your guide🙂 It worked! Thank you!

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for the record:

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Hi,
the instructions are good, but isn’t this more of a workaround for advanced users rather than a solution to the problem? Why was the “minimal-usbvm” service added when there are already instructions on the Qubes forum on how to disable this feature?
It’s February 9, 2026, and the default sys-usb installation in Qubes 4.3 blocks access to USB drives from the file manager, which also means that you can’t mount an external drive as a backup destination in “Backup Qubes.” This is nonsense, because the default sys-usb configuration becomes useless for many people without technical knowledge, and moreover, we can announce in the documentation that Qubes does NOT support external drives and Qubes virtual machine backups by default :slight_smile: Additionally, we can say that the solution is to remove sys-usb… Then the USB devices will be redirected to Dom0, but at least the backup will work. Let’s be serious.

PS. sys-usb does not support mounting USB drives from the user level in the file manager, but at the same time sys-usb supports Bluetooth…

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I bet it made sense for one of the developers :laughing: - fulfilling their particular use case.

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I was annoyed by this after I installed 4.3 but I’ve developed a habit of opening each USB drive in it’s own disposable qube ( “Attach to new disposable qube” ). I created an offline-dvm for this. Technically, it’s more secure having each usb drive in it’s own qube. I’ll probably continue doing this even if sys-usb is again capable by default to mount drives.

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