How to Install and Setup VNC on Linux

VNC, which stands for Virtual Networking Computing, is a remote connection system and sharing system that, with its emergence in the 1990s, provided remote access to the desktop graphical environment on a server for Linux systems similar to MSTSC on Windows.

The VNC software also supports the Windows operating system, and communication with the Linux server through this software has become much more efficient and simple for Windows users.

This control system can manage files and software on computers connected to the Internet, and Users can even remotely intervene in their server settings via VNC using the Linux command line. VNC even offers the ability to use keyboard and mouse clicks to communicate with the server and apply settings. This software has been able to facilitate the tasks of Linux administrators without the need for physical presence and they can access the Linux server desktop remotely through VNC.

To benefit from the features of this software, you need to install and run the VNC server on the Linux system, and you also need a VNC viewer and a secure TCP/IP connection to interact with the VNC server. In this situation, you can connect to the computer on which the VNC server component is configured and manage the remote computer through a Duplicate screen that is presented to users by the server from the remote computer.

Therefore, in this article, we have decided to teach how to install and set up VNC in Linux distributions based on Debian and RHEL distributions through the most advanced version of VNC software (TightVNC) so that you can connect to the VNC server through the SSH tunnel and Interact with the VNC server using the graphical desktop environment and VNC client program on your local system.

If you are eager to set up a VNC server on Linux distributions, don’t waste time and follow the VNC installation and configuration steps up to the end of the article.

Steps to install and configure VNC in different Linux distributions

  prerequisites

• First, you need to buy a Linux VPS running Linux distributions based on RHEL or Debian, like Ubuntu so that you can configure the VNC server on it.
• you should have non-root user privileges.
• Configure a powerful and popular firewall, we recommend the UFW firewall.
• Local system running a VNC client compatible with SSH tunnel connections.

Note: There are many VNC client programs in Linux that you can choose from vinagre, krdc, RealVNC, or TightVNC according to your needs and compatibility with your system.

Step 1: Installing the desktop environment

If you have installed a minimal version of the operating system, which by default only provides a command line interface and no GUI, The first step to installing VNC should be to install the GNOME or XFCE GUI or other graphical options so that you can easily interact with the remote VNC server.

First, connect to your server through an SSH tunnel and update your Linux system packages:

sudo apt update

Then run the following command to install the GNOME desktop environment, which is more compatible with RHEL-based distributions:

$ sudo dnf groupinstall "Server with GUI"   [On RHEL/CentOS/Fedora and Rocky Linux/AlmaLinux]

The XFCE GUI, which provides a fast and stable connection together with the TightVNC software, is more compatible with Debian-based distributions. Therefore, to install XFCE on Debian-based distributions, enter the following command so that by installing the xfce4-goodies packages, your desktop environment will have more advanced features:

$ sudo apt install xfce4 xfce4-goodies      [On Debian, Ubuntu and Mint]

Note that when installing Xfce you will be prompted to set the default display manager. Display Manager is a tool that provides a graphical user interface for selecting and entering the desktop environment.

The choice of display manager in this tutorial does not affect the connection to the VNC server because you will be using XFCE or GNOME to connect to the VNC client, XFCE or any GUI has already logged you in as a non-root user, therefore, select the display manager that suits your needs and press Enter, and choosing it will not make any changes in this tutorial.

Step 2: Installing the TightVNC server

After you have installed the desktop environment, it is time to install the TightVNC software. This software allows remote desktop management and control. Install TightVNC via the yum command.

Run the following command to install TightVNC on RHEL-based distributions:

$ sudo yum -y install tigervnc-server xorg-x11-fonts-Type1  [On RHEL/CentOS/Fedora and Rocky Linux/AlmaLinux]

To install TightVNC on Debian-based distributions, enter the following command:

$ sudo apt install tightvncserver      [On Debian, Ubuntu and Mint]

Step 3: Creating a normal VNC user

To communicate with the remote desktop, you must define a normal user with a username and password.

In this tutorial, we considered Opera as a user, so you should replace Opera with your username in the command:

$ sudo useradd Opera

OR

$ sudo adduser Opera

$ sudo passwd Opera

Step 4: Setting the VNC password for the user

To set the password for the user, first log in to the user account by executing the su-Username command and then enter the vncpasswd command:

[root@[Opera ~]# su - Opera

[Opera@Opera ~]$ vncpasswd

Password:

Verify:

Note: The password set in the previous step is for accessing the SSH session, while the password we define in this step is for connecting to the remote VNC server desktop. Also, please note that the password must be between 6 and 8 characters, and more than 8 characters cannot be set.

Note: After the password is confirmed, you will be able to define a view-only password. Setting this password is for situations where you want to share the VNC server desktop with other users, but do not allow them to interfere in the management of the VNC server through the mouse and keyboard.

Also, this command creates the directory “.vnc” which contains the passwd file in the user’s home directory.

To make sure the password file is created, you can use the following command:

# ls -l /home/Opera /.vnc

-rw------- 1 Opera Opera 10 Jul 22 15:23 passwd

It should be noted that to change the password and add a view-only password, you must use the following command again:

vncpasswd

Up to this point, you have successfully installed and started the VNC server. In the next step, we need to configure VNC to launch the graphical user interface and provide access to the server through the graphical interface.

Step 5: Configuring the VNC server

The VNC server must be configured to connect to the GUI at startup.

In this tutorial, we will use the ~/.vnc/config file in the user configuration settings to configure TigerVNC and connect to the GNOME GUI.

$ vim ~/.vnc/config

Then add the following settings to it:

session=gnome

geometry=1920x1200

localhost

alwaysshared

The session option has been added to specify the session you want to connect to, and the geometry option provides VNC desktop resolution.

After applying the changes, log out of the user login using the following command and log in again as the Root user.

$ exit

Fortunately, users in TigerVNC can map a user to a specific port in the /etc/tigervnc/vncserver.users file thanks to its default configuration settings:

# vim /etc/tigervnc/vncserver.users

The <display_port>=<username> parameters play a role in the configuration file.

In the following command, as an example, we considered Opera user for display port: 1.

# This file assigns users to specific VNC display numbers.

# The syntax is =. E.g.:

#

# :2=andrew

# :3= Liosa

:1=Opera

If you want to add another user, set port: 2 along with the desired user name and continue in the same way.

Step 6: Starting the Tigervnc server

Up to this point, you have set the necessary changes, now it’s time to start the VNC server. In this step, we want to run the VNC server with one user.

When VNC is first started, by default it will run on port 5901 (belonging to the root user). This port is a display port introduced in VNC with ID:0 and VNC can be run on other ports such as :2, :3, and… Note: What is important to remember is that when working with VNC servers, :X is a display port that points to and refers to port 5900 + X.

In the example below, we created users with the usernames Opera, Loisa, Justin, and Ravi with their specific IDs and ports.

User's                   Port's                     ID's

5900                       root                       :0

5901                       Opera                      :1

5902                       ravi                       :2

5903                       Loisa                      :3

5904                       Justin                     :4

As you can see, in our example, Opera has port 5901 and ID: 1, and according to the algorithm above, to add a new user, Id: 5 and port 5905 will be set for it.

Now to start and run the VNC service for the specified user with the display port: 1 Run the following command:

# systemctl start vncserver@:1 --now

# systemctl enable vncserver@:1 –now

Use the following command to check whether the VNC service is running:

# systemctl status vncserver@:1

As we provided access to the VNC server for the user with display port:1, if you want the VNC service to be applicable for other users, just replace the display port of the desired user:1 in the above command.

Step 7: Configuring the VNC port on the firewall

For Opera users, it is necessary to open port 5901 in your system’s firewall (ufw) and iptables.

# iptables -A INPUT -m state --state NEW -m tcp -p tcp --dport 5901 -j ACCEPT

OR

# firewall-cmd --zone=public --add-port=5901/tcp

OR

$ sudo ufw allow 5901/tcp

In our example, where we specified the port and ID for other users, if we want to open their ports in the firewall, use the following command as a guide:

# iptables -I INPUT 5 -m state --state NEW -m tcp -p tcp -m multiport --dports 5902:5904 -j ACCEPT

OR

# firewall-cmd --zone=public --add-port=5902-5904/tcp

OR

$ sudo ufw allow 5901:5910/tcp

Then restart the Iptables service by running the following commands:

# service iptables save

# service iptables restart

Or

# firewall-cmd --reload

# systemctl restart firewalld

Step 8: Downloading VNC Client

In this step, download and install VNC viewer on your local Linux system.

Step 9: Connecting to the VNC desktop

• Connecting to Remote DesktopVNC through the VNC viewer

After you have successfully installed VNC Viewer, when you run it, you will be asked to enter the IP of the VNC server along with the VNC ID for the desired user (in our example it was an Opera user with Id:1).

Then you need to enter the password that you specified through the “vncpasswd” command.

Finally, you can access the Remote desktop successfully.

• Connecting to the VNC desktop through the SSH tunnel

Since VNC connections do not use an encrypted protocol. The recommended method is to create an SSH tunnel and securely forward traffic from your local machine on port 5901 to the server on the same port.

To set up SSH Tunneling on Linux, you can easily create an SSH tunnel with the following command:

ssh -L 59000:localhost:5901 -C -N -l username your_server_ip

You will then be prompted to enter the user’s password.

Make sure to replace username and server_ip_address with your server’s username and IP address.

FAQ

Conclusion

Now you have a VNC server running on your Linux server through which you can manage and control your software, settings, and files using the graphical interface and apply any desired changes by accessing the desktop graphical environment on a server in its settings.

In this article, we have taught how to install and set up VNC in different Linux distributions. We hope that you will enjoy the features of the VNC server and perform efficiently in administrative tasks.

If you have any questions or problems in any section, share them with us in the comments section so that we can solve your problem as soon as possible.

Thank you for your good choice.