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I connect to my workstation which is a linux box(Red Hat Linux) from a my laptop(windows 7 machine) through RealVNC . When I am work I use a docking station and the resolution of it is quite high and my laptop has lower resolution . So when I switch between my monitor and my laptop I need to restart vncserver everytime with the proper geometry. Searching on the internet I landed on this answer on stackoverflow.com which describes way to assign a different geometry on the fly . The key here is the randr argument while starting vncserver . So the first thing I did is to ensure that Xrandr is installed on my linux box :

which xrandr 

This gives the following output :


Next I tried running the server with the command :

 vncserver -geometry 1600x1200 -randr 1600x1200,1440x900,1024x768

But the server didn't start . Next I started the server with only the -geometry argument and without the randr argument as given in the second answer .

Next from the terminal I issued the xrandr command and got the following error :

Xlib:  extension "RANDR" missing on display ":1.0".

What does the above error mean and what am I missing here ?

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Are you using RedHat or Linux native vncserver? I've noticed that vncserver doesn't support RANDR. I'm trying to see if there is a way to get it working. –  wisemonkey Jul 18 '14 at 17:59

1 Answer 1

I would guess, off the top of my head, that your version of VNC doesn't support RANDR. Are you sure it's supported?

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