Remotely Connecting to Ubuntu via VNC

Overview

A VNC (Virtual Network Computing) is a graphical desktop sharing system that can remotely control another computer.

On your local computer, please install a supported VNC Client:

• On Windows, you can use TightVNC, RealVNC, or UltraVNC.

• On macOS, you can use the built-in Screen Sharing program, or can use a cross-platform app like RealVNC.

• On Linux, you can choose from many options, including vinagre, krdc, RealVNC, or TightVNC.

Using Windows

If you don’t already have PuTTY installed, please follow the link https://sdsc-ucsd.atlassian.net/wiki/spaces/SC/pages/110034995.
Also, download a supported VNC Client, if you haven’t already. In this example, we will use TightVNC.

1. Connect to your server through PuTTY and open the terminal window.

2. On your server, update your list of packages.

   sudo apt update

3. Now, install the Xfce desktop environment and TightVNC server

   sudo apt install xfce4 xfce4-goodies sudo apt install tightvncserver

4. To complete the VNC server configuration, create the initial configuration file and set up a secure password.

   vncserver
   Open

   

   Passwords must be between 6-8 characters. If your password has more than 8 characters, it will be automatically truncated.
   After setting your password, the following should appear with your_hostname = your_instancename:

   Open

   

   Note: if you want to change your password or add a view-only password, you can do so with the following command:

   vncpasswd

5. Now we configure the VNC server, by first stopping the default VNC server instance.

   vncserver -kill :1

6. Backup and modify the startup file.

   mv ~/.vnc/xstartup ~/.vnc/xstartup.bak nano ~/.vnc/xstartup

   This will create a new xstartup file and open it in the text editor nano. Add the following lines:

   #!/bin/bash xrdb $HOME/.Xresources startxfce4 &

   To save and exit, press CTRL+X, Y, then ENTER

7. We make the startup file executable and restart VNC server.

   sudo chmod +x ~/.vnc/xstartup vncserver

8. Now we connect to the VNC Desktop.
   Right-click on the top bar of the terminal window, then select Change Settings.

   Open

   

9. On the directory on the left-hand side of PuTTY, expand SSH and click on Tunnels.
   In Source Port enter: 59000
   In Destination enter: localhost:5901
   Click Add, then Apply.

   Open

   

10. Open your VNC viewer client and connect to localhost:59000. You should see something like the following:

    Open

    

Using Mac or Linux

If you haven’t already, please download a supported VNC Client. In this example, we will use TightVNC.

1. Connect to your server and open the terminal window.
   Instructions on how to connect to your server through SSH can be found here:
   https://sdsc-ucsd.atlassian.net/wiki/spaces/SC/pages/110034993

2. On your server, update your list of packages.

   sudo apt update

3. Now, install the Xfce desktop environment and TightVNC server

   sudo apt install xfce4 xfce4-goodies sudo apt install tightvncserver

4. To complete the VNC server configuration, create the initial configuration file and set up a secure password.

   vncserver
   Open

   

   Passwords must be between 6-8 characters. If your password has more than 8 characters, it will be automatically truncated.
   After setting your password, the following should appear with your_hostname = your_instancename:

   Open

   

   Note: if you want to change your password or add a view-only password, you can do so with the following command:

   vncpasswd

5. Now we configure the VNC server, by first stopping the default VNC server instance.

   vncserver -kill :1

6. Backup and modify the startup file.

   mv ~/.vnc/xstartup ~/.vnc/xstartup.bak nano ~/.vnc/xstartup

   This will create a new xstartup file and open it in the text editor nano. Add the following lines:

   #!/bin/bash xrdb $HOME/.Xresources startxfce4 &

   To save and exit, press CTRL+X, Y, then ENTER

7. We make the startup file executable and restart VNC server.

   sudo chmod +x ~/.vnc/xstartup vncserver

8. Now we connect to the VNC Desktop, by creating an SSH connection.
   In the terminal, input the following:

   ssh -L 59000:127.0.0.1:5901 -C -N -l ubuntu your_server_ip

   Replace ubuntu and your_server_ip with the sudo non-root username and server IP address.
   Note: it may be needed to replace 127.0.0.1 with localhost, depending on the Ubuntu version.

9. Open your VNC client and connect to localhost:59000.

   Open

   

Setup VNC as System Service

The following steps will configure the VNC server to start every time the server boots up.

1. Create new unit file

   sudo nano /etc/systemd/system/vncserver@.service

   Add the following lines and replace the ubuntu value in User, Group, Working Directory and PIDFILE username as appropriate:

   [Unit] Description=Start TightVNC server at startup After=syslog.target network.target [Service] Type=forking User=ubuntu Group=ubuntu WorkingDirectory=/home/ubuntu PIDFile=/home/ubuntu/.vnc/%H:%i.pid ExecStartPre=-/usr/bin/vncserver -kill :%i > /dev/null 2>&1 ExecStart=/usr/bin/vncserver -depth 24 -geometry 1280x800 -localhost :%i ExecStop=/usr/bin/vncserver -kill :%i [Install] WantedBy=multi-user.target

   Save and close the file.

2. Enable the new unit file.

   sudo systemctl daemon-reload sudo systemctl enable vncserver@1.service

3. Turn off current VNC server instance.

   vncserver -kill :1

4. Start systemd service.

   sudo systemctl start vncserver@1

   You can use the following command to verify that it started.

   sudo systemctl status vncserver@1

   The output should say active (running)

5. To reconnect to the server, start your SSH tunnel (Step 8 in either of instructions above).

Setup SSH Tunnel Information in PuTTY

1. Open a new PuTTY sesssion and enter in the Host Name information, but do not click Open yet.

2. Under Saved Sessions, label what you want the server and SSH information to be known as. Then click Save.

   Open

   

3. On the directory on the left-hand side of PuTTY, expand SSH and click on Tunnels.
   In Source Port enter: 59000
   In Destination enter: localhost:5901
   Click Add.

   Open

   

4. Return back to the default main page, by clicking on Session in the directory.
   Click Save once again.

5. The next time you reboot the instance and reopen PuTTY, load the saved session. If you click on SSH → Tunnels, you should find the added SSH port forwarding. Then click Open.

Open

Open