Custom Linux OS Template

While DaDesktop offers a range of popular Linux distributions, you might occasionally need a specific distro that isn’t on our standard list. We’re happy to accommodate most mainstream Linux distros for this purpose. Simply provide the download location for the ISO file and the server where you’d like to make the Custom OS template available in Italy.

Important:

About Disk Partitioning
1. Custom templates need just one disk partition, or two: an EFI/Boot partition and a separate system and data partition.
2. LVM partitioning is not supported; please avoid using LVM.
3. Using an incorrect partition scheme will prevent disk auto-resize and other functions from working properly.

Linux Template

Once we’ve downloaded the ISO file to the server, you’ll find it listed under Admin Menu->OS IMAGES->ISO FILES in your account.

From there, you can create the template by navigating to Admin Menu->OS IMAGES->CUSTOM OS TEMPLATES

Please follow this guide carefully, and complete all the steps as otherwise full DaDesktop operation is likely not to work.

Install the operating system.
Set the default username to “student” and the password to “student”.
Configure the “student” account for automatic login.
Apply the DaDesktop wallpaper or your own custom design
Many newer distros default to Wayland as their display driver. While Wayland does function within DaDesktop, we currently recommend switching back to X11.

To disable Wayland:

edit /etc/gdm/custom.conf, e.g.
```
# Uncomment the line below to force the login screen to use Xorg
        WaylandEnable=false
        
```
log out and log back in
Install spice-vdagent; the easiest way is through your package manager. Note: It may already be installed depending on your distro.
- After successful installation, restart the machine. You should then see two running processes: spice-vdagent and spice-vdagentd
Next, install qemu-guest-agent—again, your package manager is the recommended tool.
Install X11VNC. Note: For certain distributions, you may need to add extra repositories. For Red Hat–based systems like Oracle Linux or Rocky Linux, this often includes the ‘epel’ repo.

Configure X11VNC

Ensure X11VNC is installed.
Open a root shell by running sudo -i

Run the following command to enable X11VNC to start automatically at boot.

cat > /etc/xdg/autostart/x11vnc.desktop <<EOF
                [Desktop Entry]
                Type=Application
                Exec=/usr/bin/x11vnc -N -no6 -rfbportv6 -1 -allow 10.0.3.1 -nopw -shared -alwaysshared -forever -repeat -nowireframe -noscr -nocursorshape -skip_lockkeys -cursor_drag -grab_buster -deferupdate 10 -speeds 6000,5000,20 -afteraccept announce-vnc-users.sh -gone announce-vnc-users.sh
                Hidden=false
                X-MATE-Autostart-enabled=true
                X-MATE-AutoRestart=true
                Name[en_US]=X11VNC
                Name=X11VNC
                Comment[en_US]=Share desktop over VNC
                Comment=Share desktop over VNC
                EOF

Create a desktop notification script by executing the commands below.

cat > /usr/local/bin/announce-vnc-users.sh <<EOF
        notify-send -a x11vnc "VNC users connected: $RFB_CLIENT_COUNT"
        EOF
        chmod +x /usr/local/bin/announce-vnc-users.sh

Restart the machine.
Review the firewall settings: ensure TCP port 5900 is open, e.g.,

ss -pntl
Disable the sudo password (recommended).
Confirm everything is working.

Upon connection, if the URL changes to include a token query parameter, the setup is complete—X11VNC is functioning. The text box at the bottom left of the screen, used for bi-directional copy/paste between your local and virtual desktops, should now be operational.

Please Note

To add extra optional features such as

DDWebdav to sync the Trainer’s content folders across all participant machines,
or DDUpload – for easy file uploads within a DaDesktop environment;

Please contact DaDesktop Tech Support.