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Date: Thu, 16 Jan 1997 14:06:37 -0600 (CST)
From: Mark Tinguely <tinguely@plains.nodak.edu>
Message-Id: <199701162006.OAA28563@plains.nodak.edu>
To: Beatrice.Chambet@dassault-elec.fr, multimedia@FREEBSD.ORG
Subject: Re: Multicast
Sender: owner-multimedia@FREEBSD.ORG
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>  I'm trying a audioconference software on IP. When I give a
>  multicast IP address like 239.255.1.1/1234, i have the following message :
>  No route to host.
>  
>  How can i know if my kernel support multicast address IP ?

You are running FreeBSD verion >= 2.0 then multicast will be in by default.

Check your /etc/sysconfig and see if the lines that look something like
below are uncommented:

static_routes="multicast loopback"
route_multicast="224.0.0.0 -netmask 0xf0000000 -interface ${hostname}"
route_loopback="${hostname} localhost"

--mark.