raspberry PI - no X11

[Shlomo Solomon]

On Sun, 4 Feb 2018 12:26:41 +0200
shimi <linux-il at shimi.net> wrote:

> On Sun, Feb 4, 2018 at 11:54 AM, Shlomo Solomon
> <shlomo.solomon at gmail.com> wrote:
> 
> > I really don't know how I screwed this up, but I've been "playing"
> > with this for hours with no success.
> >
> > I have a raspberry PI file server. I rarely use the GUI and when I
> > do it's usually over VNC (I use KRDC) or with ssh -X.
> >
> > As of today:
> > 1 - KRDC won't connect
> >
> > 2 - ssh -X pi at pi   (pi is defined in /etc/hosts) gives only a
> > console login and says:
> > X11 connection rejected because of wrong authentication.
> >
> > 3 - I connected a monitor directly to the PI and it will not accept
> > the pi password when I try to login to X11 - but DOES accept the
> > root password. So X11 is OK, but only for root - not the regular pi
> > user.
> >
> >
> >
> Not a Pi expert so I'll answer this as if it was a generic Linux
> question...
> 
> 1. You didn't mention if you tried to simply reset the pi user
> password from root by invoking 'passwd pi'?
> 
> 2. Assuming SSH authentication via public key (I have to assume
> because I couldn't find the authentication method in the
> question...), one has to make sure that the home directory of the
> user authenticating to is with not-too-open permissions (for starters
> the safest bet is chmod 700), likewise for all all ancestor
> directories of said home directory, because if they're too open,
> another user might be able to simply replace your homedir with
> another homedir, and then log in as you; To discourage such
> possibility, SSH blocks authentication whenever the permissions are
> too wide.
> 
> 3. If all the above fails (or you already tried and everything is in
> order), I would look at /var/log/messages (or Pi equivalent) while
> attempting to login to the user, to see if any hint is available
> there. Also, over ssh, using 'ssh -v' might output something useful.
> 
> HTH,
> 
> -- Shimi

Thanks, but the problem is not the pi password or ssh. I CAN login over
ssh, but do not get X11. And this is exactly what happens when I
connect a monitor and keyboard directly to the PI.

Just in case, I added -v to the ssh command as you suggested and here
are the last few lines of the output:

debug1: Next authentication method: password
pi at pi's password: 
debug1: Authentication succeeded (password).
Authenticated to pi ([10.0.0.51]:22).
debug1: channel 0: new [client-session]
debug1: Requesting no-more-sessions at openssh.com
debug1: Entering interactive session.
debug1: Requesting X11 forwarding with authentication spoofing.

The programs included with the Debian GNU/Linux system are free
software; the exact distribution terms for each program are described
in the individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Sun Feb  4 11:25:07 2018
debug1: client_input_channel_open: ctype x11 rchan 3 win 65536 max 16384
debug1: client_request_x11: request from ::1 36814
debug1: channel 1: new [x11]
debug1: confirm x11
X11 connection rejected because of wrong authentication.
debug1: channel 1: free: x11, nchannels 2





-- 
Shlomo Solomon
http://the-solomons.net
Claws Mail 3.11.1 - KDE 4.14.30 - Dolphin 4.14.3 - LINUX Mageia 5