How can I specify a display?

Question

When I run some programs over SSH, such as firefox &, I get an error

Error: no display specified 

I would like to open ma

Answer 1

I through vnc to understand the X11 more. To specify the display to get a many-displayed program, export DISPLAY=IP:DisplayNum.ScreenNum

For example,

vncserver :2
vncserver -list
echo '$DISPLAY'=$DISPLAY 
export DISPLAY=:2  # export DISPLAY=IP:DisplayNum or export DISPLAY=:DisplayNum for localhost; So that can vnc connect and see the vnc desktop :2 if $DISPLAY is not :2.
echo '$DISPLAY'=$DISPLAY

Answer 2

Even i faced the same in CentOS 6.8.

yum reinstall xorg*

End your current session and open another session in tool like mobiXterm. Make sure session has X11 forwarding enabled in the tool.

Answer 3

Please do NOT try to set $DISPLAY manually when connecting over SSH.
If you connect via SSH -X and $DISPLAY stays empty, this usually means that no encrypted channel could be established.

Most likely you are missing the package xauth or xorg-x11-xauth. Try to install it on the remote machine using:

sudo apt-get install xauth

or

sudo apt-get install xorg-x11-xauth

After that end and restart your SSH connection. Don't forget to use SSH -X so that X Window output is forwarded to your local machine.

Now try echo $DISPLAYagain to see if $DISPLAY has been set automatically by the SSH demon. It should show you a line with an IP address and a port.

Answer 4

Try installing the xorg-x11-xauth package.

Answer 5

Try

export DISPLAY=localhost:0.0

Answer 6

$ export DISPLAY=yourmachine.yourdomain.com:0.0
$ firefox &