VNC viewer shows black screen for one user and normal for the other

Posted on

VNC viewer shows black screen for one user and normal for the other – A server stack is the collection of software that forms the operational infrastructure on a given machine. In a computing context, a stack is an ordered pile. A server stack is one type of solution stack — an ordered selection of software that makes it possible to complete a particular task. Like in this post about VNC viewer shows black screen for one user and normal for the other was one problem in server stack that need for a solution. Below are some tips in manage your linux server when you find problem about linux, centos, centos7, vnc, .

I installed TigerVNC on a CentOS 7 and configured its service for two users (user1 and user2). It worked perfectly until recently. When I try to connect with VNC Viewer with user1 it shows just a black screen, meanwhile with user2 everything is fine. Both ports for each of them are opened.

P.S. I have mainly used user1, I was working one some apache configurations and when I restarted the server it happened.

Thank you in advance.

cat /etc/sysconfig/vncservers showed this output:

THIS FILE HAS BEEN REPLACED BY /lib/systemd/system/vncserver@.service

Meanwhile cat /lib/systemd/system/vncserver@.service showed this:

Description=Remote desktop service (VNC)


ExecStartPre=/bin/sh -c '/usr/bin/vncserver -kill %i > /dev/null 2>&1 || :'
ExecStart=/usr/sbin/runuser -l <USER> -c "/usr/bin/vncserver %i"
ExecStop=/bin/sh -c '/usr/bin/vncserver -kill %i > /dev/null 2>&1 || :'


I’m posting my own answer here in hope that it will help someone in the future.

So, I just closed the port from before, removed the previous vncserver@:<port number>.service , created a new vncserver service in another port but still coulnd’t reload or restart the service.

After checking with sudo tail /var/log/messages I ended up deleting this folder /tmp/.X11-unix/X4 , then restarted the service.

It finally works.

I suspect that your vncservers service isn’t configured properly.

Edit /etc/sysconfig/vncservers and make sure that your file looks like so:

VNCSERVERS="6:root 7:itai"
VNCSERVERARGS[6]="-geometry 1024x768"
VNCSERVERARGS[7]="-geometry 1152x864"

The first line configures which port each user will connect to… 6 translates to port 5906 and 7 translates to 5907.
The other lines configure the screen resolution for each user.

If you make any changes in the configure, don’t forget to restart the service:

service vncservers restart

I hope that helps.

Leave a Reply

Your email address will not be published. Required fields are marked *