Custom OS Template (Linux)

While DaDesktop keeps a range of popular Linux distros on hand, there may be times when you need a specific distro that isn't part of our standard collection. DaDesktop is pleased to accommodate most mainline Linux distros for this. Just let us know where to grab the ISO file and which server you'd like to publish the Custom OS template on.

Important:

About Disk Partitioning
1. Customised templates require only a single disk partition or two partitions: one for EFI/Boot and the other for system and data.
2. An LVM partition is not supported, so please avoid using LVM.
3. An incorrect partition scheme will cause disk auto-resize and other functions to fail.

Linux Template

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

From there, you can prepare the template by going to Admin Menu->OS IMAGES->CUSTOM OS TEMPLATES.

Kindly follow this guide with care and complete every step, as missing anything may prevent DaDesktop from operating properly.

Install the OS
Set the default username to "student"; set the password to "student"
Configure the "student" account for Auto Login
Use the DaDesktop or your own brand wallpaper
Some distros now default to Wayland as their display driver. Wayland does work within DaDesktop; however, for the time being we 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
        
```
logout and login again
Install spice-vdagent; using your package manager is typically the best route. Note: this may already be installed depending on your distro
- After a successful installation, restart the machine, and you should spot the two running processes, spice-vdagent and spice-vdagentd
Install qemu-guest-agent; again, using your package manager is generally the simplest method
Install X11VNC. For certain distros, you may need to add extra repos, such as the 'epel' repo for Redhat-based distros like Oracle Linux or Rocky Linux
Configure X11VNC
- ensure X11VNC is installed
- run the command sudo -i to open a root shell
- run the following command to allow X11VNC to auto-start upon reboot
```
cat > /etc/xdg/autostart/x11vnc.desktop <
```
Create the desktop notify script by running the commands below
```
cat > /usr/local/bin/announce-vnc-users.sh <
```
Reboot
Check the firewall settings, i.e., ensure TCP port 5900 is open, e.g.

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

Upon connecting, if the URL changes to a new one with a token query parameter, you're all set. This confirms X11VNC is working. Additionally, the text box at the bottom left of the screen, used for copy/paste between your local desktop and the virtual desktop, should now be functional.

Please Note

To add extra optional features such as

DDWebdav for syncing the trainer's content folders to each participant's machine,
or DDUpload for easily uploading files within a DaDesktop machine;

Please reach out to DaDesktop Tech Support.