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Dear all,

On our office VLAN we see numerous (about 10 percent of all traffic on all switchports) NBNS "UNDEFINED" queries:

1052 23.531946 NBNS 92 Name query NB UNDEFINED<00>

We also see normal NBNS queries for hostnames, wpad, etc. However we are unable to find any explanation for the "UNDEFINED" queries. Please can someone shed some light on this?

Many thanks :)

This question is marked "community wiki".

asked 26 Oct '17, 01:14

markvdb's gravatar image

accept rate: 0%

edited 26 Oct '17, 02:52

grahamb's gravatar image

grahamb ♦

Can you share a capture?

(26 Oct '17, 08:08) Papa Packet

As a trace contains customer data, I prefer not to, but if you tell me what you're looking for (in the capture) I'll extract it or make a short trace. Thx!

(27 Oct '17, 00:25) markvdb
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question asked: 26 Oct '17, 01:14

question was seen: 1,794 times

last updated: 27 Oct '17, 07:16

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