Re: No DISPLAY set in -X Tunneling

From: Richard E. Silverman (
Date: 04/22/05

Date: 21 Apr 2005 21:16:55 -0400

Some of what you've written is a little vague -- for example, you talk
about "the host computer," and it's not clear whether you mean the SSH
client or server (they are both "hosts"). However, two things suggest you
have a basic misunderstanding;

> 2. On the remote machine which is running X I issue a 'ssh -vvvX
>' and am able to sign on the host machine. (These are in a
> router network.)
> ...
> The only thing I saw was that the xauth generate command contacted the X
> server. If it isn't working for that user on the host, I really am not sure
> how this can work.

In SSH forwarding, the SSH *client* is running an X server (i.e. has an X
display). The X forwarding allows X clients running on the SSH server to
use the SSH client's display. The "xauth generate" command establishes a
new X security key for use with this session, and so naturally talks to
the X server to accomplish that.

  Richard Silverman

Relevant Pages

  • Re: Explanation of SSH
    ... I am still unclear on how SSH works exactly. ... Client issues SSH command and names server ... "Shopper" says "server sends back its public host and server keys ... Surely there is only one public key it sends ...
  • Re: ssh security question
    ... In my case - the client is a windows client and the ssh is embedded into the windows nx client. ... Is there any reason I can't run ssh-keygen on the server and copy the private key to the client - and the public key to the "authorised" directory? ... sniffer can catch your passwords, and it would make it trivial to log in ...
  • Re: Publishing a SSH Server
    ... Your unix box cannot reply to SSH request, ... Create a client address set for your unix box (ip address from to are the ... Jim Harrison [ISA SE] ... In that case the server is a SecureNET client but still it doesn't work.... ...
  • Re: FC6 VPN
    ... Then you can run any application you would like off the server by simply running it, or if you want to run a whole session, use gnomesession. ... ssh client that supports X forwarding, which is want you want to be looking at. ... SSH allows you to forward any local port to any remote port. ... If you need to connect to, say a windows share, you would forward your local port to the linux server through the ssh tunnel. ...
  • Re: Trouble with X11 over SSH on Mandriva 2010.0
    ... If next clean install/update causes ssh to break, ... installed the sshd daemon/service package (OpenSSH Server) on the server. ... correct values for client and server. ...