Warning: untrusted X11 forwarding setup failed: xauth key data not generate

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Level 1

12 points

Warning: untrusted X11 forwarding setup failed: xauth key data not generate

Upon connecting to a RedHat Enterprise Linux server via ssh -X I get the following:

Warning: untrusted X11 forwarding setup failed: xauth key data not generated
Warning: No xauth data; using fake authentication data for X11 forwarding.

I have previously (as in last week, ending 11/1/2008) been able to use x11 forwarding from the machine I'm trying to connect to. This problem also occurs with other servers, meaning it must be a problem with my local machine. Any suggestions are welcome.

MacBook Pro, Mac OS X (10.5.5)

Posted on Nov 6, 2008 7:32 AM

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Answer 1

BobHarris

Level 9

53,081 points

Nov 6, 2008 10:21 AM in response to zburnham

I get that if I use


ssh -Y ...

but NOT with -X.

Do you have a $HOME/.ssh/config or /etc/ssh_config file that is specifying ForwardX11Trusted?

Mostly I ignore the message when I get it as, my X11 forwarding works OK, AND I'm in an environment where my fellow employees could do much naster things to me (and get fired for it), than spoofing my X11 sessions.

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Answer 2

zburnham Author

Level 1

12 points

Nov 6, 2008 1:24 PM in response to BobHarris

I get this message both with -Y and -X.

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Answer 3

zburnham Author

Level 1

12 points

Nov 11, 2008 7:27 AM in response to zburnham

Turns out my issue was with a bad temp file. I would get a warning that the system couldn't read something in /tmp which I unfortunately did not write down, but it looked like /tmp//:0 . My solution was to restart the system, and that worked, I'm back in business. I'm assuming the system sets up that file at startup.

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Answer 4

Courcoul

Level 6

18,558 points

Nov 11, 2008 7:53 AM in response to zburnham

Just worthy of mentioning when doing X11 tunnelling is that the authentication credentials are keyed to the IP address. Meaning that if you are mobile and change access point/provider/etc, resulting in a change of the Mac's IP address, any open sessions will fail and you will need to reauthenticate.

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