When we install the minimal copy of CentOS Server, it only gives us the “Command Line” interface.
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But some people prefer GUI instead and for this they install Full version of Gnome on CentOS. Actually there is a better way and that is to install VNC. VNC provides a lightweight virtual desktop than full blown version of Gnome.
To run the VNC Server on CentOS, we have to install these required packages:
sudo yum groupinstall Desktop
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sudo yum install tigervnc-server
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sudo yum install xorg-x11-fonts-Type1
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This is optional:
sudo yum install vnc
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To start VNC Server on boot
sudo chkconfig vncserver on
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To setup users’ VNC password:
vncpasswd
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Edit the /etc/sysconfig/vncservers file:
sudo nano /etc/sysconfig/vncservers
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Add the following to the end of the file:
VNCSERVERS="1:arbab"
VNCSERVERARGS[1]="-geometry 1024x600"
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The iptables rules need to be amended to open the VNC ports:
sudo iptables -I INPUT 5 -m state --state NEW -m tcp -p tcp -m multiport --dports 5901:5903,6001:6003 -j ACCEPT
sudo service iptables save
sudo service iptables restart
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Restart the VNC Server:
sudo service vncserver restart
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Now kill the VNC Server:
vncserver -kill :1
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Edit the xstartup file in .vnc directory:
nano .vnc/xstartup
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Comment the last line and run the Gnome:
#twm &
exec gnome-session &
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Restart the service:
sudo service vncserver restart
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Now, download VNCViewer onto our desktop computer from which we want to access the shared desktop. Connect using ServerIP/Name:1 (:1 is for the VNC server window), In my case it is centos:1.
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Enter the password that we created using the vncpasswd command:
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We now have GUI access to our server.
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Ability to connect for multiple users:
Create a local user, using the following command:
sudo adduser ali
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Create a password for newly created user:
sudo passwd ali
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Switch to the newly created user and run vncpasswd command for it:
su ali
vncpasswd
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Edit the /etc/sysconfig/vncservers file:
sudo nano /etc/sysconfig/vncservers
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Add these lines for new user:
VNCSERVERS="1:arbab 2:ali"
VNCSERVERARGS[1]="-geometry 1024x600"
VNCSERVERARGS[2]="-geometry 1024x600"
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Restart the VNC service:
sudo service vncserver restart
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Kill the vncserver session for new user and edit the xstartup file:
su ali
vncserver -kill :2
cd ~
nano .vnc/xstartup
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Modify the file so it looks like this:
#twm &
exec gnome-session &
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Restart the VNC service:
sudo service vncserver restart
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Connect with newly created user using centos:2, Where centos is my server name:
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Enter the password that we created using the vncpasswd command:
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We now have GUI access to our server for newly created user.
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Hope this will help you!