From owner-freebsd-net@freebsd.org  Thu Jun 25 16:18:44 2015
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Date: Thu, 25 Jun 2015 18:18:35 +0200 (CEST)
From: Emeric POUPON <emeric.poupon@stormshield.eu>
To: "Andrey V. Elsukov" <bu7cher@yandex.ru>
Cc: freebsd-net@freebsd.org
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Subject: Re: Multicast routing questions
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Thread-Topic: Multicast routing questions
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Ok thanks, I understand this case.
But the problem is that we perform a lot of unnecessary mforward calls from=
 ip_input.

The mrt route cache lookup is performed thanks to the src/dst addresse coup=
le.
The interface of the cached route does not match the current interface and =
that is what prevents "infinite" loops.

Is that really how it is meant to be done?

Emeric

----- Mail original -----
De: "Andrey V. Elsukov" <bu7cher@yandex.ru>
=C3=80: "Emeric POUPON" <emeric.poupon@stormshield.eu>, freebsd-net@freebsd=
.org
Envoy=C3=A9: Jeudi 25 Juin 2015 07:48:44
Objet: Re: Multicast routing questions

On 24.06.2015 18:13, Emeric POUPON wrote:
> Hi,
>=20
> Actually, I don't really understand why imo.imo_multicast_loop is set
> to 1 in send_packet, ip_mroute.c
>=20
> It seems we don't need to loop the packet once it is mrouted?=20

I think this can be used for the case, when on the router some app has
been joined to multicast group on the specific interface used as
outgoing in send_packet.

--=20
WBR, Andrey V. Elsukov