How to rebuild default-dvm

I have been using the default-dvm, which is the template for DisposableVM, to watch websites (which are in a gray area) where I can watch animations, etc. I may have gotten infected while doing so, and I would like to recreate the default-dvm. I am using the default debian-12-xfce that was selected when I installed Qubesos, how can I recreate it?

If you used the default-dvm template, there is nothing to do unless you used the template itself for your activities. If you remember your disposable qube having a name like “dispXXXX”, then you are fine, since they are only temporary and get removed after use without affecting the original template they are based on.
If you still want to recreate it, create a new AppVM based on a template of your choice and enable “Disposable template” in the qube’s advanced settings.

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And then set the new qube as the default disposable template in the
Global Settings Window. Delete the old qube used as default dvm

I never presume to speak for the Qubes team. When I comment in the Forum I speak for myself.

Thanks. I was trying to create it using the existing default-dvm as a reference, but the item does not appear in the drop-down list of GlobalSettings in QubesOS. Is there some condition?

Thank you, I have been trying to create a Qube in Qube Manager with different Type/Template/Networking settings, but I can’t seem to find it in the globalSettings drop down list. How can I satisfy the conditions to be listed in the GlobalSettings?

Did you check the “Disposable template” option in the qube’s Settings → Advanced tab?

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Thanks, that’s what I needed to check there. I quickly checked it and it now appears in the GlobalSettings drop-down list. Now I can recreate it if I had an internet connection with Default-dvm.

What does this mean?

The only condition for a default disposable template is that the qube
be a disposable template. You set this by selecting that option in
the qube’s settings, or using qvm-prefs QUBE template_for_dispvms True

  1. In this case you will need to delete the existing
    default-disposable-template and to do THAT you will need to stop it from
    being the default. Do this under Global Config.
  2. Then delete debian-12-xfce-dvm
  3. Create a new qube named debian-12-xfce-dvm using default settings, and
    enable “Disposable template” in the Settings window, Advanced Tab.
  4. Make the new qube the default disposable template in Global Config.

Instead of steps 3 and 4, you could use the same mechanism that Qubes
uses, using salt.
The state file is at /srv/formulas/base/virtual-machines-formulas/qvm/default-dispvm.sls
and you run it using sudo qubesctl state.apply qvm.default-dispvm

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Hi, I found myself in a similar situation when I accidentally installed something in default-dvm without realizing I was in default-dvm at the time. I have a few questions:

Will this impact the sys templates since I had to switch them from default-dvm to my new default-dvm?

What is the purpose of default-mgmt-dvm and do I need to reinstall it as well?

Will changing or removing the default-dvm have any consequences?

I also mistakenly used dd (to wipe something) on xvda instead of my USB device while working in a disp vm (dispXXXX). As a result, my disp vm (dispXXXX) stopped functioning, so I powered it down and launched a new disp vm (dispXXXX) while correctly dd’ing the USB device. Will this impact my device outside the dispvm (dispXXXX) in any way?