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Re: '"GLX" missing on display' Problems


On Fri, 30 Apr 2004 luke.kendall@cisra.canon.com.au wrote:

> On 28 Apr, Harold L Hunt II wrote:
> >  http://x.cygwin.com/docs/faq/cygwin-x-faq.html#q-ssh-no-x11forwarding 
> 
> Interesting info, though it confuses me a little.
> 
> Where it says:
> 
> "It is easiest to just override trusted X11 forwarding by passing -Y to ssh
> in place of -X. The -Y does the same thing as -X, but it enables trusted
> X11 forwarding for the current connection."
> 
> does it mean to say "It is easiest to just override X11 forwarding..."?
> Otherwise it seems to be saying you can override trusted X forwarding
> with trusted X forwarding.
> 
> When it says "OpenSSH 3.8 enables trusted X11 forwarding by default when
> connecting to an ssh server that supports trusted X11 forwarding.",
> does it mean that overrides the setting in the /etc/ssh_config file?
> In other words, which default is the most default?

Correct is:

OpenSSH 3.8 now connects as _un_trusted client by default. The prior versions
always connected as trusted (normal) clients. 

Actually it should read:

OpenSSH 3.8 uses untrusted X11 forwarding by default when connecting to an 
ssh server that supports untrusted X11 forwarding. Most ssh servers for GNU/Linux 
are versions of OpenSSH that do support untrusted X11 forwarding, so using 
OpenSSH 3.8 from Cygwin will result in a connection that uses untrusted X11 
forwarding by default. You will quickly notice that this is the case if most 
of your X applications are now killed when you try to copy and paste or if 
xdpyinfo returns only a fraction of the supported extensions that it does if 
run locally.

It is easiest to just override untrusted X11 forwarding by passing -Y to ssh 
in place of -X. The -Y does the same thing as -X, but it enables trusted X11 
forwarding for the current connection.

> What happens if your config file has both "ForwardX11 yes" and
> "ForwardX11Trusted yes"?  Which is the default then?  Is it bad to have
> both?  Is it bad to have one set to yes and the other to no?

I don't know. Try it. 

> Apologies if these are stupid questions.
> 
> I notice that I do have openssh 3.8 installed, and also note that the
> man page mentions ForwardX11Trusted in only one place, with no
> explanation, and the section on X11 and TCP forwarding mentions only
> ForwardX11 and the -X and -x options, not the -Y.  So I couldn't get
> answers to my questions there.  (This is true in the latest Cygwin, as
> of a day or so ago.)

bye
	ago
-- 
 Alexander.Gottwald@s1999.tu-chemnitz.de 
 http://www.gotti.org           ICQ: 126018723


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