From owner-freebsd-transport@freebsd.org  Tue Sep 13 15:49:25 2016
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To: transport@freebsd.org
From: Hannes Mehnert <hannes@mehnert.org>
Subject: dupliceated icmp echo request
Message-ID: <ed0692b4-59a8-a918-90d0-2eb204884c98@mehnert.org>
Date: Tue, 13 Sep 2016 16:39:16 +0100
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hello,

(sorry in case this is the wrong mailing list)

while doing some network testing, I discovered that my FreeBSD (r304285,
but likely earlier + released ones as well) sends out two
(bytewise-)identical ICMP echo requests shortly after each other when I
ping the broadcast (IPv4) address on an interface [tested with: tap,em,iwm].

This behaviour does not meet my expectations - is there any specific
reason for this behaviour; it behaves well (sending out a single ICMP
echo request) if I ping a unicast host.

hannes