Description of Problem: OpenSSH's XForwarding seams to break if one is using IPv6. Xforwarding works fine if you are *only* using IPv4, *but*, when using IPv6 OpenSSH seams sometimes "forget" to open the IPv4 port on localhost, but IPv6 on localhost is always opened. Note that this behavior seams to be somewhat random, so it might take several retries to occur. Version-Release number of selected component (if applicable): OpenSSH 3.1p1 on RH7.2, and Skipjack beta1. How Reproducible: Enable IPv6 in the OS, (re)start OpenSSH, log in, try using Xforwarding... Can you reproduce this?
I can reproduce this using the current OpenSSH package for 7.1. OpenSSH's X forwarding only seems to bind to ::1 and never to 127.0.0.1. I'm working around this by adding: X11UseLocalhost no to /etc/ssh/sshd_config. I don't have the most recent version of XFree installed, so maybe it knows how to speak X over IPv6, which would resolve the probem. 2% uname -a Linux graves 2.4.18 #3 SMP Fri Apr 12 18:52:51 IST 2002 i686 unknown 3% rpm -q openssh openssh-3.1p1-1
With openssh-3.4p1-2 this problem seams to be gone, so I'm closing it.