Re: No response to XDMCP queries using modular X.org xdm

[Brian Morley <b.morley%rocketmail.com@localhost>]

--- On Sun, 6/11/11, Matthias Scheler <tron%zhadum.org.uk@localhost> wrote:

> On 5 Nov 2011, at 22:52, Brian Morley wrote:
> 
> > I've bee playing with this for a few days now and I
> > seem to be getting precisely nowhere with it.  xdm
> > flatly refuses to respond to any queries it is sent. 
> > Tracing with Wireshark shows the queries are entering the
> > system but it does not appear to be doing anything with
> > them.  Playing with xdm's no-deamon and debug options
> > does not reveal anything at all either - it is as if the
> > packets are somehow not reaching xdm at all.

> What's the output of "netstat -a -f inet" or if you have
> "lsof" installed the output of "lsof -p $(pgrep xdm)"?

Thanks for the reply.  netstat output:
Active Internet connections (including servers)
Proto Recv-Q Send-Q  Local Address          Foreign Address        State
tcp        0      0  n1c.home.64982         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.64983         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.64992         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.64993         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.64994         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.64998         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.64999         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.65119         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.65315         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.65316         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.65317         t2.home.x11            ESTABLISHED
tcp        0      0  n1c.home.ssh           t2.home.65525          ESTABLISHED
tcp        0      0  *.ssh                  *.*                    LISTEN
tcp        0      0  *.printer              *.*                    LISTEN
udp        0      0  *.1019                 *.*                   

lsof output:
COMMAND PID USER   FD   TYPE             DEVICE SIZE/OFF     NODE NAME
xdm     269 root  cwd   VDIR                0,0      512        2 /
xdm     269 root  txt   VREG                0,0    99256 29003702 
/usr/pkg/bin/xdm
xdm     269 root  txt   VREG                0,0  1306638  4169987 
/lib/libc.so.12.164
xdm     269 root  txt   VREG                0,0    39733 23739611 
/usr/lib/libpam.so.1.0
xdm     269 root  txt   VREG                0,0    31150  4169990 
/lib/libcrypt.so.0.2
xdm     269 root  txt   VREG                0,0    27731 23722492 
/usr/pkg/lib/libXdmcp.so.6.0.0
xdm     269 root  txt   VREG                0,0    14831 23722485 
/usr/pkg/lib/libXau.so.6.0.0
xdm     269 root  txt   VREG                0,0  1397428 23722516 
/usr/pkg/lib/libX11.so.6.3.0
xdm     269 root  txt   VREG                0,0    76337 23722596 
/usr/pkg/lib/libXpm.so.4.11.0
xdm     269 root  txt   VREG                0,0    85110 23722528 
/usr/pkg/lib/libXext.so.6.4.0
xdm     269 root  txt   VREG                0,0    12342 23722809 
/usr/pkg/lib/libXinerama.so.1.0.0
xdm     269 root  txt   VREG                0,0    96607  4170023 
/lib/libutil.so.7.15
xdm     269 root  txt   VREG                0,0   106305 23722499 
/usr/pkg/lib/libICE.so.6.3.0
xdm     269 root  txt   VREG                0,0    36398 23722522 
/usr/pkg/lib/libSM.so.6.0.1
xdm     269 root  txt   VREG                0,0   437244 23722545 
/usr/pkg/lib/libXt.so.6.0.0
xdm     269 root  txt   VREG                0,0   120306 23722584 
/usr/pkg/lib/libXmu.so.6.2.0
xdm     269 root  txt   VREG                0,0    80886 10995721 
/libexec/ld.elf_so
xdm     269 root    0u  VCHR                2,2      0t0 23389196 /dev/null
xdm     269 root    1u  VCHR                2,2      0t0 23389196 /dev/null
xdm     269 root    2w  VREG                0,0       29 22322594 
/var/log/xdm.log
xdm     269 root    3u  VREG                0,0        6 22318683 / (/dev/wd0a)
xdm     269 root    4u  IPv6 0xffff800007938630      0t0      TCP *:65534 
(LISTEN)
xdm     269 root    5u  IPv6 0xffff800007928cb0      0t0      UDP *:xdmcp

I'm not overly familiar with those commands but that lsof seems to suggest that 
it is only listening on IPv6 addresses - IPv6 isn't set up on this network.  
Does anyone know why that might be and how to get it listening on IPv4?