Another one of quick tutorials, this time on the topic of VNC server on CentOS/RHEL

Prerequisite for the VNC server is GUI interface – GNOME for CentOS 8/RHEL 8.

But, before we start installation procedure, we will check if Wayland display manager is configured as default display manager.

First, we need to change to root by entering following command:

su

Then, enter following:

vi /etc/gdm/custom.conf

Wayland should be set to false:

WaylandEnable=false 

When you are done with editing, quit vi with

:q!

Let’s proceed with VNC Server installation

Installation command for TigerVNC is 

dnf install tigervnc-server tigervnc-server-module

Next we, will switch to user which will use VNC and set VNC server password:

su – informaticar
vncpasswd

Now let’s switch back to root account by running following command:

exit

Next, we will have to configure VNC server. We will create new configuration file vncserver@.service in /etc/system/system/

su

Then run following command (file will be opened in vi editor)

vi /etc/systemd/system/vncserver@.service

New blank screen will open, and you need to enter following configuration into it (change informaticar with your username)

[Unit] 
Description=Remote desktop service (VNC) 
After=syslog.target network.target 

[Service] 
Type=forking 
WorkingDirectory=/home/informaticar 
User=informaticar 
Group=informaticar 

PIDFile=/home/informaticar/.vnc/%H%i.pid 

ExecStartPre=/bin/sh -c '/usr/bin/vncserver -kill %i > /dev/null 2>&1 || :' 
ExecStart=/usr/bin/vncserver -autokill %i 
ExecStop=/usr/bin/vncserver -kill %i 

[Install] 
WantedBy=multi-user.target

When you are done, type :wq! to save and quit

Before starting VNC we need to disable SELinux

setenforce 0
sed -i 's/enforcing/disabled/g' /etc/selinux/config

Now, with following commands we will reload VNC server, enable it to start at startup and check if it is up and running

systemctl daemon-reload
systemctl start vncserver@:1
systemctl enable vncserver@:1
systemctl status vncserver@:1

Service is up and running.

Next, lets check and verify that VNC server is listening

netstat -tlnp

Next, we will add VNC port exceptions to firewall. We will open port 5901

firewall-cmd --permanent --add-port=5901/tcp
firewall-cmd –reload

We will now try and connect to our VNC server via Windows client. One thing that is important and worth mentioning – VNC is not secure by itself, and it is completely unencrypted. SSL tunneling is preferred method of connecting to VNC, but more on that in other article.

Right now, let’s just test VNC with VNC viewer – it works!

Disclaimer