Originally posted by: SystemAdmin

Some background:

1. oslevel -s

5300-05-06

OpenSSH_4.3p2, OpenSSL 0.9.7l 28 Sep 2006

I've edited /etc/ssh/sshd_config, enabled X11Forwarding, and restarted sshd. However, when I connect in this fashion from an X terminal window on a nearby RHEL4 client:

ssh -l root -X -C <hostname>

...and then try and run something like "xclock", I get this:

Error: Can't open display

If I check my $DISPLAY variable, it is blank. I've used this functionality numerous times in the past with an RHEL4 client and AIX host, and it dawned on me that the AIX servers on which it is working all have an older version of sshd that we compiled in house some time ago: sshd version OpenSSH_3.7.1p1. Sure enough, I installed that old version on this same server, started its sshd, and this works fine.

Has anyone else experienced this problem when using IBM's compiled version of sshd ? I've already done a good bit of research on the web but haven't been able to find anything.

Thanks,
Hounster

Originally posted by: SystemAdmin

Well, looks like I should have started my "web research" right in this forum. I have never used this forum before, but figured I should have really searched the forum BEFORE making my post, so gave it a shot, and came up with this:

==========================================================
Re: Remote: No xauth program; cannot forward with spoofing.
Originally posted: 2007 Feb 08 02:29 AM
Joachim Gann
Post new reply

some recent Versions of the openssh package for aix come with unreasonable defaults:

$ strings $(which sshd)|grep xauth
...
/usr/contrib/bin/xauth
Adding this line to /etc/ssh/sshd_config should solve it:
XAuthLocation /usr/bin/X11/xauth
==========================================================

...which I'm 99% confident will apply in my case also:

1. strings /usr/sbin/sshd|grep xauth (This is the IBM sshd)

/usr/contrib/bin/xauth

1. strings /usr/local/sbin/sshd|grep xauth (This is our old version)

/usr/X11R6/bin/xauth
Thanks,
Hounster

Originally posted by: mahespth

Also to note is that in various versions of openssh there is a bug if ipv6 is not configured, this also causes the problem that you speak of.

Adding the '-4' flag to sshd causes it to use the ipv4 functions only, this resolves the problem.

(chssys -a "-4" -s sshd; stopsrc -f -s sshd && startsrc -s sshd)

Regards
Steve Maher

Originally posted by: SystemAdmin

I have a same problem.
AIX5.3+4.3.0.5300 doesn't work with X11Forwarding yes.
No .Xauthority file is created, no DISPLAY is set.
-4 option doesn't solve it.
AIX5.3+3.6.1.5201 does work.
any idea?

Originally posted by: SystemAdmin

Humodada, be sure and look at my second post on May 17th. The fix in my case was to set this parameter in sshd_config, then restart the daemon:

XAuthLocation /usr/X11R6/bin/xauth

Hounster

Originally posted by: SystemAdmin

Indeed.
I just overlooked your 2nd post.
It works perfect.
Thanks.