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I cannot use X applications on one of my servers. (The same client succeeds in connecting to other servers so the problem is not on the client side).

I connect with ssh -vvv -Y -4 jet (tried also with -X instead of -Y, same problem) to force IPv4 (which solves already a previous error). But then when I start an application requiring X I get the following:

debug1: client_input_channel_open: ctype x11 rchan 3 win 65536 max 16384
debug1: client_request_x11: request from 42026
debug2: fd 7 setting O_NONBLOCK
debug3: fd 7 is O_NONBLOCK
debug1: channel 1: new [x11]
debug1: confirm x11
debug2: X11 connection uses different authentication protocol.
X11 connection rejected because of wrong authentication.
debug2: X11 rejected 1 i0/o0
debug2: channel 1: read failed
debug2: channel 1: close_read
debug2: channel 1: input open -> drain
debug2: channel 1: ibuf empty
debug2: channel 1: send eof
debug2: channel 1: input drain -> closed
debug2: channel 1: write failed
debug2: channel 1: close_write
debug2: channel 1: output open -> closed
debug2: X11 closed 1 i3/o3
debug2: channel 1: send close
debug2: channel 1: rcvd close
debug2: channel 1: is dead
debug2: channel 1: garbage collecting
debug1: channel 1: free: x11, nchannels 2
debug3: channel 1: status: The following connections are open:
  #0 client-session (t4 r0 i0/0 o0/0 fd 4/5 cc -1)
  #1 x11 (t7 r3 i3/0 o3/0 fd 7/7 cc -1)

xterm Xt error: Can't open display: JET:10.0

xauth list gives me

JET:11  MIT-MAGIC-COOKIE-1  8d5c49524a122751ec382da3613c9408
JET:10  MIT-MAGIC-COOKIE-1  6582c5c546ca979132e2d32c64ef481d

echo $DISPLAY gives me


So I have cookies for this display.

My SSH version on the server is:

OpenSSH_5.3p1, OpenSSL 1.0.0-fips 29 Mar 2010

From various solutions found on the web there was something like

xauth generate $DISPLAY MIT-MAGIC-COOKIE-1

but when I run this command I get the same error than when I run a X program (even if I rm ~/.Xauthority just before).

I haven't sudoed after ssh, I auth via a private key. My server is on CentOs and I have the following ssh server configuration sudo cat /etc/ssh/sshd_config|egrep -v "^#"

Protocol 2
SyslogFacility AUTHPRIV
LogLevel DEBUG3
PasswordAuthentication yes
ChallengeResponseAuthentication no
GSSAPIAuthentication yes
GSSAPICleanupCredentials yes
UsePAM yes
X11Forwarding yes
X11DisplayOffset 10
X11UseLocalhost no
Subsystem   sftp    /usr/libexec/openssh/sftp-server

Any hint on what could cause this?

share|improve this question
See I had the same problem, removing ~/.ssh/rc fixed it. – user259583 Oct 3 '13 at 15:15

I'm just taking a shot in the dark here, but since you're having xauth issues, maybe it has to do with the trusted X11 forwarding. Have you tried taking the same steps from an ssh connection made via ssh -vvv -X -4 jet?

share|improve this answer
yes I tried both -X and -Y, same error in both cases – jolivier Oct 25 '12 at 7:41

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