# X windows over telnet

**URL:** https://forums.suse.com/t/x-windows-over-telnet/27998
**Category:** SLES Configure-Administer
**Created:** [March 15, 2016, 9:13pm UTC](https://forums.suse.com/t/x-windows-over-telnet/27998 "2016-03-15T21:13:26Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![georgeston](https://avatars.discourse-cdn.com/v4/letter/g/5e9695/32.png) [@georgeston](https://forums.suse.com/u/georgeston)
#### Post date: [March 15, 2016, 9:13pm UTC](https://forums.suse.com/t/x-windows-over-telnet/27998/1 "2016-03-15T21:13:26Z")

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How do I enable X Windows over telnet?

I realize that is is not secure and one should use ssh; but, we are on a closed intranet and my clients only have access to telnet.

Users can connect using telnet, but when trying to run an X application, get “Error: Can’t open display”, even though the DISPLAY environment variable is correctly set.

I set DISPLAYMANAGER\_XSERVER\_TCP\_PORT\_6000\_OPEN=“yes” in /etc/sysconfig/displaymanager  
Removed “-nolisten tcp” in file /etc/X11/xdm/Xservers  
Add the line “xhost +” to the file /etc/X11/xinit/xinitrc

X works with ssh but not telnet

Thanks

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### Author: ![ab1](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@ab1](https://forums.suse.com/u/ab1)
#### Post date: [March 15, 2016, 9:45pm UTC](https://forums.suse.com/t/x-windows-over-telnet/27998/2 "2016-03-15T21:45:09Z")

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If your client machines have X windows (and nothing blocking connections  
from the server to those systems using the X protocol) you could  
potentially set DISPLAY to the client IP and port, then magically forward  
that all directly there (is not really using telnet, but it could be setup  
via telnet).

I agree; this (using telnet) is a terrible, horrible, no-good idea. You  
may have a lot better luck setting up VNC access to the server, or giving  
the end users VMs, or something. Knowing the business case behind this  
access/setup may help come up with other ideas.

–  
Good luck.

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### Author: ![Jens-U](https://avatars.discourse-cdn.com/v4/letter/j/d78d45/32.png) [@Jens-U](https://forums.suse.com/u/Jens-U)
#### Post date: [March 16, 2016, 7:47pm UTC](https://forums.suse.com/t/x-windows-over-telnet/27998/3 "2016-03-16T19:47:27Z")

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Hi georgeston,

> X works with ssh but not telnet

it is not clear to me if the clients can reach the server directly, network-wise, and if there are any limits. It might be that using “ssh” creates a tunnel through the ssh connection, allowing to forward the X traffic to the client.

Also, you did not specify on which host you modified the X server configuration - this has to be done on each client’s machine.

Please start by trying to connect to port 6000 on an affected client’s machine from the server (where the clients try to start the X application), i.e. via “telnet 6000”. If telnet establishes a connection, that client’s X server is reachable.

Once we know if the networking is right and the user’s X server is reachable from your server machine, we can continue to debug why your users cannot connect via their X applications.

Regards,  
Jens
