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I've found a strange line in the tcpdump output. Normally UDP packets are dumped in the following form:

timestamp IP srcaddress.port > dstaddress.port: UDP, length packetlength

but this is just:

timestamp IP srcaddress > dstaddress: udp

note the missing port numbers, the lowercase udp and the missing packet length.

Does somebody know what's this?

share|improve this question
Just udp, not [|udp]? What does tcpdump -h print? – user137177 Apr 30 '15 at 19:43
@GuyHarris: as you can see this was a long time ago.. not even sure how to reproduce it in a different environment.. – Karoly Horvath May 1 '15 at 10:01

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