How to deploy a full-fledged VDI on Ubuntu Linux and ThinLinc: an alternative to Windows Terminal Server

wget https://www.cendio.com/downloads/server/tl-4.20.0-server.zip

Replace the link with the one you got in step #3.

Step 5: Unzip the archive and go to the folder with the unzipped files

sudo apt install unzip -y
unzip tl-4.20.0-server.zip
cd tl-4.20.0-server

Where tl-4.20.0-server– is the name of the archive you downloaded

Step 6: Installing ThinLinc Server

Launching the installer:ThinLinc comes with a convenient installation script that will automatically pull in the necessary dependencies.

sudo ./install-server

The installer will ask for input at certain points, for example, to 'Press Enter to continue' or to confirm specific options.

ThinLinc Server Configuration Utility

After ThinLinc installation, the server setup utility will immediately follow. It is recommended to continue with the setup.

During setup, you will be prompted to install missing packages and confirm your settings:

• Run ThinLinc setup now [Yes/no]? Yes
• Server type [Master/agent]? Master
• Automatically install the necessary packages [Yes/no]? Yes
• Do you want to continue with installation [Yes/no]? Yes

Install LDAP components so that you can log in to the system using an account within AD.

Automatically install the necessary packages [Yes/no]? Yes

Specify what should be used for external access:

Externally reachable address to use [ip/hostname/manual]? ip

Please enter the system administrator's email address:

Administrator email []? Please provide your contact email.

ThinLink offers a web interface for administering the terminal server. You can disable it later. However, for now, please enter a strong password:

Web Administration password? YOURS_RELIABLE_PASSWORD

Installing AppArmor configuration is recommended:

Install AppArmor configuration [Yes/no]? Yes

Once the installation and configuration is complete, you will receive a message confirming successful installation.

Step 7: Adding the path to sudo

To ensure that the system always finds ThinLinc commands, you need to edit the file visudo

sudo visudo

and replace the value in the line “Defaults secure_path=” with 

“/sbin:/bin:/usr/sbin:/usr/bin:/opt/thinlinc/bin:/opt/thinlinc/sbin”

Step 8: Checking and Configuring Access Ports

ThinLinc operates over SSH (port 22) for primary traffic and uses ports 1010 (web administration interface) and 300 (web client).

If you have ufw enabled, allow access:

sudo ufw default deny incoming && \
sudo ufw default allow outgoing && 
sudo ufw allow 22/tcp && \
sudo ufw allow 300/tcp && \
sudo ufw reload

Step 9: Optimize GUI performance for remote access

A command that will create a global configuration file and force compositing and animations to be disabled for all users to improve remote desktop responsiveness.

sudo cp /etc/xdg/kwinrc /etc/xdg/kwinrc.backup 2>/dev/null ||true
sudo bash -c 'cat > /etc/xdg/kwinrc << EOF
[Compositing]
Enabled=false
OpenGLIsUnsafe=true

[Plugins]
blurEnabled=false
contrastEnabled=false
kwin4_effect_translucencyEnabled=false
slideEnabled=false
zoomEnabled=false

[Windows]
ElectricBorderDelay=0
ElectricBorderCooldown=0

[Effect-PresentWindows]
BorderActivate=9

[KWin]
AnimationDurationFactor=0
EOF'

Step 10: Connection

You can connect to a remote desktop in two ways: through the native ThinLinc client or directly in the browser https://YOUR_SERVER_IP:300

The client can be downloaded from the Cendio -> Download -> For users page.

As you can see, the client is very similar to the MS RDP client. The settings allow you to configure device forwarding and shared clipboard. Remote desktop display quality settings are also quite advanced.

Step 11 (Optional) Disabling access to the server via a web browser

Since browser access creates additional attack vectors, it is best to disable access to the web admin panel on port 1010 and access to the remote desktop web client.

This can be done by disabling the relevant services + closing ports in the firewall.

Disabling services:

# Stop the web client and admin panel
sudo systemctl stop tlwebclient tlwebadm

# We prohibit their autostart
sudo systemctl disable tlwebclient tlwebadm

Deny access to port 300:

sudo ufw deny 300/tcp
sudo ufw reload

Potential problems and recommendations for hardware

Even with proper installation, there may be some nuances specific to remote desktops.

Problem #1: No sound or video lags in the browser

Reason: Ubuntu 24.04 installs browsers (Firefox, Chromium) in Snap format by default. These packages run in an isolated sandbox, which:

• Doesn't see ThinLinc virtual sound channels.
• Slower UI rendering due to containerization layers.

Example of installing Google Chrome from a .deb package:

wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
sudo apt install ./google-chrome-stable_current_amd64.deb

Problem #2: Image "crumbling" or lag

Reason: Weak internet connection or insufficient processor resources to compress the video stream.

• Solution: Make sure that optimization (Adaptive Compression) is enabled in the ThinLinc Client settings.
• Solution: Make sure you are using a KDE Plasma (X11) session and not Wayland.

Recommended system requirements

To ensure a truly comfortable experience when working with KDE via ThinLinc (without stuttering sound or freezing when opening browser tabs), we recommend the following VPS specifications:

Even with a minimal configuration, a dedicated server will deliver significantly higher VDI performance. If you plan to use a terminal server as part of a business infrastructure, it's best to consider dedicated resources to ensure stable performance for a multi-user system.

ThinLinc can also use the GPU for 3D graphics processing using VirtualGL. This requires installing proprietary GPU drivers and running the vglrun command to launch applications that require GPU processing.