Getting “Xlib: PuTTY X11 proxy: wrong authentication protocol attempted”? I have the answer :)
Here’s the scenario:
You ssh to a remote server with your login and either sudo or su to another user to run some application that uses a X Windows front end. There is a firewall between your desktop and the remote server that allows only ssh connections (port 22). When you run into the error “Xlib: PuTTY X11 proxy: wrong authentication protocol attempted”. What to do?
jason $ echo $DISPLAY
localhost:10.0
jason $ su – oracle
oracle’s Password:
oracle $ xterm
Xlib: connection to "localhost:10.0" refused by server
Xlib: PuTTY X11 proxy: wrong authentication protocol attempted
xterm Xt error: Can’t open display: localhost:10.0
On recent OpenSSH Server releases, you can simply enable “ForwardX11Trusted yes” in the /etc/ssh/sshd_config file and restart the OpenSSH server. If you’re not using a recent OpenSSH Server release or if you can’t for security or political reasons, what could you do? Give up? It’s simpler than you think.
You need to temporarily transfer the authorization to the other account. First, get the key from your account:
aspc2o1/unix:10 MIT-MAGIC-COOKIE-1 bc334c66cfec3c5c3d5b0efc4ee9d3ad
Next, sudo/su to the other account and add the authorization key.
oracle $ xauth add aspc2o1/unix:10 MIT-MAGIC-COOKIE-1 bc334c66cfec3c5c3d5b0efc4ee9d3ad
Now, you should be able to start any X Windows application, assuming that your DISPLAY variable is set to go through the ssh tunnel:


Very useful and rare to get this kind of exact and precise work around. Million thanks.
wonderful solution….thanks a ton….
Awesome. Glad I was able to find this. Works perfectly and exactly what I was looking for!
Glad I could help
Thank you for the tip Jason! I’ve been struggling with this issue for months and been doing silent Oracle installations as a result at one of my clients. I just tried your suggestion and it worked like a charm.
Many, many thanks!
hey i m not able to open the display when i want to open text editor or gvim it gives the error
Xlib: connection to “yamsrv1.ece.gatech.edu:11.0″ refused by server
Xlib: PuTTY X11 proxy: wrong authentication protocol attempted
(gedit:16728): Gtk-WARNING **: cannot open display:
any help is appreciated
Rahul,
If you’re using Windows, you may have to tell your X Windows software to allow the incoming connection from the putty session. Which X Windows software are you using?
I’m guessing you’re using Windows because putty isn’t too terribly common on Unix/Linux/MacOSX desktops.
Jason
hey i am using xming + putty
on windows desktop
xming version 6.9.0.31
i am trying to access linux based server remotely
regards
rahul
Hi Rahul,
I haven’t used xming very often but the last time I followed http://www.straightrunning.com/XmingNotes/trouble.php Does this help?
jason
I went thru that before only but the thing is my xserver is somehow not able to connect…
I still dont know
i m sure abt this cos none of my friends had this problem and we are accessing the same remoyte server so no change is required at the remote server side and neways we dont have root rights at remote server
can thre be any fire wall problem i m gonna try tht now …but i m not sure
but i am activatin xming before starting putty…which is how we are suppose to do
but still i donno wats the problem
which X11 authentication protocol do you have set in PuTTY?
hey I got it running
I used X11 forwarding only
The problem I gess was with my user account the xterm parameters were not set properly
and I dont have the root accesss
I donno whther you can do nething abt it without the root access…ne suggestions is welcome
I have sent the request to the college support staff
I am currently working on my friends account
congrats Rahul! I’m glad you got the x11 forwarding to work using putty
Thank you for posting this precise answer. It was just what I was looking for.
Debra, no problem
i came in to start my oracle install on a new box ( via sudo not a direct login as in the past ) at 8am monday morning and get this error – not a good start. so i cut and paste the whole message into google. your page comes up first on the list. the solution works as advertised
too easy.
thanx heaps.
I ran into the same problem, thanks for pointing me in the direction of xauth. Further googling got me the solution for my Ubuntu server:
Install pam_xauth to transfer xauth cookies between users on su. Now the problem is solved!
Thanks a bunch Jason.
I normally never post messages..but GOD bless for passing on the knowledge and information.
Thanks again!