Warning: No xauth data; using fake authentication data for X11 forwarding.

[Aldo Foot]

On Wed, Oct 15, 2008 at 1:48 PM, Jerry Feldman <gaf at blu.org> wrote:
> I am using Fedora 9 on an IA64 workstation. When I ssh -X to another host,
> the ssh authentication succeeds in under a second, but the X11
> authentication takes about 20 seconds and issues the warning:
> Warning: No xauth data; using fake authentication data for X11 forwarding.

Not sure whether this will help, but it's worth a try:
Find out the hard coded path of the xauth binary in the sshd executable.
  > strings `which sshd` | grep xauth
the above command should show a line like "/usr/bin/xauth", take note
of whatever
path you see.
Add a line to your /etc/ssh/sshd_config to read "XAuthLocation /usr/bin/xauth".
Restart sshd and see what happens.

HTH,
~af