Thank you, Comcast.

Chris Adams cma at
Fri Feb 26 17:42:15 UTC 2016

Once upon a time, Brielle Bruns <bruns at> said:
> UDP is a fun protocol - stateless, so blocking a DST of 53/UDP to
> the customer also will block responses to recursive queries that
> originate from SRC 53/UDP.  Connection tracking sorta makes it
> stateful to a point, but it can get ugly with enough traffic.

Sending queries from port 53 has been considered bad behavior and
deprecated for what, 15 years now?

Chris Adams <cma at>

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