X11-Cluster

[Severin Olloz <S.Olloz@xxxxxxx>]

Hello together...

I set up a X11-DR-Linux-Virtual-Server and it works good. The clients make a 
XDMCP-Query with a command like this:

X :1 -query 192.168.120.140

and the director of the cluster sends the UDP packets on port 177 (XDMCP) to 
the real server. The realserver becomes the request and opens a X11-session 
for the user. My ipvsadm table looks like this:

IP Virtual Server version 1.0.2 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port        Forward Weight ActiveConn InActConn
UDP  192.168.120.140:xdmcp wlc persistent 360
  -> node1:xdmcp                  Local   100    0          0
  -> node2:xdmcp                  Route  100    0          0

You see, the director is a realserver too.

But sometimes (2 or 3 times in a day), the client makes a request, the 
X11-server starts on the worksation, but there is no login window from the 
kdm-daemon on the server. I listen on the ethernet device (eth0) of the 
director and see many many XDMCP-UDP-requests to the director. I shut down 
the X11-server on the workstation, but the XDMCP-traffic remains existing. I 
must plug off and plug in the network cable and after that, all works fine 
again.

What can that be?

Can it be, that the client send UDP-packets and 1 packet goes to the 
real-server one and the other packet goes to the real server two -> chaos 
theory in action!?

I set the XDMCP-servive to persistent mode, but this ist not the solution, 
because the problem remains existing. Must I set the persistent-timeout 
higher than the 360 seconds!?

Have somebody a idea, what it can be?

Thanks very much for the help.

--
Severin Olloz