Qubes can have a steep learning curve. This means that when you are setting up a system for someone else to use, that explaining qubes in full to them can be difficult.

Here we try to create restricted sys-guis, where they only need to see the parts that pertain to them. Basically a administrative gui login (dom0), and a restricted user sys-gui login.

The restricted user gui login serves the following: - Cut down the user interface to just the necessary interface to tasks that they need to do
- example: Scrolling through a list of 63 AppVMs to find the correct one is a bit cumbersome for me, and could be confusing to new users.
While the 'find' option is there, that would require explaining, and for them to know the name of the appvm they want and/or the command they want. (I.E. they cannot use process of eliminiation of the available options to figure out which one they want) - example: They may not need to see that sys-firewall type qubes connect to sys-net. Instead some users may be better off just knowing about a sys-internet (renamed from sys-firewall for them), and sys-vpn-to-work, and may be better off not even knowing about sys-net on day one.

Please note that this procedure has not gone through any qubes-os security review

Step 1: set up the basic sys-gui:

qvm-prefs default-mgmt-dvm template fedora-38

sudo qubesctl top.enable qvm.sys-gui
sudo qubesctl top.enable qvm.sys-gui pillar=True
sudo qubesctl --all state.highstate

sudo qubesctl top.disable qvm.sys-gui

qvm-prefs  work-sys-gui guivm sys-gui

Then you can logout, then change the upper right corner option on the login screen to "sys-gui" then login again.

You should now be logged into sys-gui. (sys-gui now seems to have a blue hamster as the desktop background). Great. Now quick, log out and log back into dom0 before the screen lock triggers!

From basic sys-gui to a restricted user

Give yourself a way to unlock the screen when logged into sys-gui:

Before anything else, lets create a way for you to unlock the screen when you are running sys-gui:

sudo /bin/sh -c "sudo grep '^user:' /etc/shadow | sed 's/^user:\([^:]*\):.*/sys-gui:\1/' &gt;  /etc/qubes-sys-gui-user-passwords"
sudo chmod 600 /etc/qubes-sys-gui-user-passwords

NEW_PASSWORD_HASH=`sudo grep "^$1:" /etc/qubes-sys-gui-user-passwords | sed 's/^[^:]*://'`

ESCAPED_PASSWORD_HASH="${NEW_PASSWORD_HASH//\//\\\/}"

qvm-run --pass-io --no-gui --user=root $1 "sed -i 's/^user:[^:]*:/user:$ESCAPED_PASSWORD_HASH:/' /etc/shadow"

chmod a+x /usr/local/fix-guivm-password.sh

#!/usr/bin/bash -e

USER=`whoami`
if [ $USER = 'user' ]; then
    VM='sys-gui';
else
    VM="sys-gui-$USER";
fi

echo "Throwing away parameter $1 and running $VM as our sys-gui domain instead"

print_usage() {
cat &gt;&amp;2 &lt;&lt;USAGE
Usage: $0 vmname
Starts given VM and runs its associated GUI daemon. Used as X session for the
GUI domain.
USAGE
}

if [ $# -lt 1 ] ; then
    print_usage
    exit 1
fi

# Start VM, gui-daemon and audio
qvm-start --skip-if-running "$VM"
qvm-start-daemon --watch "$VM" &amp;

/usr/local/bin/fix-guivm-password.sh $VM

# Run the inner session (Xephyr) and wait until it exits
exec qvm-run -p --no-gui --service "$VM" qubes.GuiVMSession

Now you should be able to logout of dom0, change the upper right corner option on the login screen to "sys-gui" then login again.

This time when the screen locks, it should be the same password as "user" in dom0 (hopefully)

If you look at the qubes available, it's just the work-sys-gui qube. Now, you can load the settings for the work-sys-gui qube, and you can run things in work-sys-gui with your default network. You can also change the network from sys-firewall (or whatever your default network was) to "none", and network access will no longer be available. perfect.

However, you are not allowed to change network access back from "none" to sys-firewall (or whatever your default network was). This looks like a policy issue! But we have 2 problems now. #1. Every time we want to change the policies, we need to log out and log back in as dom0. And #2 dom0 gets the notifications of what policy was denied when we tried to enable sys-firewall. This takes forever and is not condusive to trial and error.

We will fix those parts now by installing a "useless sys-gui-vnc" that does not have network access (and cant be reached remotely).

Step 1: set up the basic sys-gui:

From basic sys-gui to a restricted user

Give yourself a way to unlock the screen when logged into sys-gui:

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