Re: X11 forwarding in OpenSSH question

From: Carl Holtje (cwh0803_at_cs.rit.edu)
Date: 11/18/03 

Date: Tue, 18 Nov 2003 07:44:30 -0500

The easiest thing to do is to log in as follows:

ssh -X {username}@{BoxB}

This will forward all X-display stuff through the SSH tunnel, and you
don't have to setup any DISPLAY variables or xhost-stuff...

Carl

NetNews wrote:
> I don't neet to set DISPLAY variable to hostA:0.0. This way X11
> traffic will never go through SSH connection.
> If you have X11 forwarding enabled DISPLAY should be st to
> localhost:11.0 or something like that. It depends which port
> SSH will open for X11 redirection. Check netstat -an | grep for 60
>
> tcp 0 0 127.0.0.1:6010 0.0.0.0:* LISTEN
> tcp 0 0 127.0.0.1:6011 0.0.0.0:* LISTEN
> tcp 0 0 127.0.0.1:6012 0.0.0.0:* LISTEN
>
>
>
> "Mike" <mikeumo@onebox.com> wrote in message
> news:5B_tb.1187$AT2.991@newssvr22.news.prodigy.com...
>
>>Hello,
>>
>>I wonder if someone could help me with this problem.
>>
>>I have two Linux boxes on LAN (both Mandrake 9.1 on i586, static IP), say
>>BoxA and BoxB. BoxA runs X server and BoxB runs sshd
>>(openssh-3.6.1p2-mdk1.2.91). I use ssh client (openssh-3.6.1p2-mdk1.2.91)
>>from BoxA to login as a user to BoxB where I run X Windows programs (say,
>>konqueror) which I want to display on BoxA. As is, situation results in
>>(case 1):
>>
>>libGL error: failed to open DRM: Operation not permitted
>>libGL error: reverting to (slow) indirect rendering
>>kbuildsycoca running...
>>libGL error: failed to open DRM: Operation not permitted
>>libGL error: reverting to (slow) indirect rendering
>>mcop warning: user defined signal handler found for SIG_PIPE, overriding
>>... # and many more as I navigate in the opened browser
>>
>>and konqueror does start, but, as it says, in a slow mode.
>>
>>
>>if I set the DISPLAY variable (in /etc/profile like DISPLAY=BoxA:0.0;
>>export DISPLAY) on BoxB to point to BoxA's display then I get (case 2):
>>
>>Xlib: connection to "192.168.1.3:0.0" refused by server
>>Xlib: No protocol specified
>>konqueror: cannot connect to X server 192.168.1.3:0.0 # i.e. BoxA display
>>
>>now if I use xhost on BoxA to add BoxB to BoxA's access control list
>
> (xhost
>
>>+BoxB) then I get only (case 3):
>>
>>kbuildsycoca running...
>>mcop warning: user defined signal handler found for SIG_PIPE, overriding
>>
>>so, there seem to be fewer problems now. Now the question:
>>
>>why ssh/sshd do not resolve connections in the first case automatically?
>>
>>I have X11 forwarding enabled in both ssh-client and sshd. It looks to me
>>that md5sum cookies do not work in the first ssh case. I also tried to
>>extract/merge .XAuthority from BoxA to BoxB with no changes in output.
>>
>>Can someone help me to understand the process of ssh forwarding and X
>
> server
>
>>authentication. The man and HOW-TO pages on this matter are confusing.
>>
>>Thank you in advance,
>>Mikhail.
>>
>>
>>
>
>
> 

-- 
"There are 10 types of people in the world: Those who understand binary
and those that don't."
$>whoami: Carl Holtje
$>mail holtje: cwh0803@cs.rit.edu
$>cu: http://www.cs.rit.edu/~cwh0803
$>whois holtje:
   System Administrator Group
   Computer Science Department
   Rochester Institute of Technology
$>

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