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Wireshark-users: [Wireshark-users] Multicast problem

From: Lars Lars <laasunde@xxxxxxxxxxx>
Date: Thu, 30 Oct 2008 17:21:38 +0100
 
Hello
 
I'm new to this mailinglist and I'm hoping to get some help on a specific problem I'm trying to debug.

An server application is setup to send udp multicast message every second. There are a number clients, including the server itself, that listen for this messages. This has worked fine for several years. Then this week I found an installation where all clients received udp multicast message except the server. So the multicast is not echo'ed back to the itself. (There is no firewall on any of the computers)
 
By starting Wireshark 1.0.4 I'm able to monitor the multicast messages\packages
Source: 172.21.1.1
Destionation : 230.21.1.200
Protocol: UDP
Source port:14800
Destionation port: 14800
 
What I'm not able to understand is how can I debug this problem using wireshark? How can I figure out if a particular udp multicast packet
is actually both sent and received by the same computer? Does this application enable me to do so? Can someone please explain how
I could go about doing so, or recommend any other utility that might aid me.
 
Thanks for your time. Appreciate any input.


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