How to configure VNC server in AlmaLinux 8.3

Solution

Install the required VNC server packages in AlmaLinux 8.3 as follows:

yum -y install tigervnc-server tigervnc

The default configuration files for the tigervnc-server are located in /etc/tigervnc. In this directory, the following files are present.

vncserver.users
vncserver-config-mandatory
vncserver-config-defaults

Map the users to a particular port by adding the following option (:x=user) in /etc/tigervnc/vncserver.users file.

:1=vnc-user1
:2=vnc-users2

You should configure one vnc session per user as AlmaLinux 8.3 only supports one unique user per GUI session per machine.

Now you will have to edit vncserver-config-defaults file to configure Xvnc parameters. The values in this file will be applied to every user unless the user has its own configuration file in $HOME/.vnc/config. The same options with different values are set in vncserver-config-mandatory file, which replaces the default configuration file and has a higher priority. The format of the configuration file is option=value.

session=gnome
#securitytypes=vncauth,tlsvnc
#desktop=myserver
#geometry=1900x1100
#localhost
#alwaysshared

Make sure the parameter session=gnome in the above code matches the name of the session desktop file in the/usr/share/xsessions directory (case-sensitive).

Run the following command to start the Tigervnc server. This command should be run as a user who will be starting and using the vnc server. The vnc password must be set while the user is logged in and not by the root.

vncpasswd

As root, start the Tigervnc server as follows:

# systemctl enable vncserver@:$x.service
# systemctl start vncserver@:$x.service

In the above command, you should replace the variable $x by the actual number configured in /etc/tigervnc/vncserver.users

systemctl enable vncserver@:1.service --now

Open vnc default port 5901 in the firewall as follows:

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

Reload firewall.

firewall-cmd --reload