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Full Version: Tcpdump What Is This?
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Robert83
Hi,

I just did a tcpdump on the test mail server, and I don't know why is this happening constantly (every second)

192.168.1.230.1088 > 234.8.7.1: udp 64

what is this?

Sincerely
Robert B
hughesjr
That ip (234.8.7.1) is on the multicast ip range (224.0.0.0 - 239.255.255.255) .... not only that, but it is in the range:

234.0.0.0 - 238.255.255.255 RESERVED

and this is what RFC 3171 says about the reserved range:
QUOTE
Applications MUST NOT use addressing in the IANA reserved blocks.


routers don't route that IP address' traffic ... so it has to be internal traffic.

I'm not sure what it is or does...I'll see if mine is doing it as well.
hughesjr
I didn't see any multicast traffic at all in a 10 minute tcpdump file ... and I sent mail in and out during the period....
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