Custom Linux OS Template

DaDesktop already carries a broad selection of popular Linux distributions, but occasionally you might require one that isn't on our standard list. We're happy to accommodate most mainstream distributions. Just let us know the ISO download location and which server you'd like to use for publishing that custom OS template.

Important:

About Disk Partitioning
1. Custom templates need only one partition, or two at most: an EFI/Boot partition and a single partition for the system and data.
2. LVM partitioning isn't supported, so please steer clear of it.
3. A wrong partition layout will prevent disk auto-resizing and other key functions from working.

Linux Template

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

You can then create the template from 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 either the DaDesktop wallpaper or your own branded one
Many distributions now default to Wayland as their display driver. Although Wayland works within DaDesktop, we currently recommend falling back to X11.

To turn off Wayland:

edit /etc/gdm/custom.conf, e.g.
```
# Uncomment the line below to force the login screen to use Xorg
        WaylandEnable=false
        
```
then log out and log back in
Install spice-vdagent – your system's package manager is usually the best path. Note: it might already be present depending on your distro
- Once installed correctly, reboot, and you should spot two running processes: spice-vdagent and spice-vdagentd
Install qemu-guest-agent, again preferably through your package manager
Install X11VNC. Bear in mind: on some distros you may need to add extra repositories, such as 'epel' for Red Hat-based distros like Oracle Linux or Rocky Linux
Configure X11VNC
- Confirm X11VNC is installed
- Run sudo -i to open a root shell
- Execute the command below to make X11VNC start automatically on reboot
```
cat > /etc/xdg/autostart/x11vnc.desktop <
```
Create the desktop notification script by running the commands below
```
cat > /usr/local/bin/announce-vnc-users.sh <
```
Restart the machine
Check the firewall settings – ensure TCP port 5900 is open. For example:

ss -pntl
Disable the sudo password prompt (recommended)
Verify success

When you connect, the URL should change to include a token query parameter – that signals X11VNC is active. The text box at the lower-left corner of the screen, used for copy/paste between your local desktop and the virtual one, should now operate as well.

Please Note

To add extra optional features such as

DDWebdav to synchronise the trainer's content folders to each participant's machine,
or DDUpload – for easy file uploads inside a DaDesktop machine;

please contact DaDesktop Tech Support.