From owner-svn-src-all@FreeBSD.ORG Fri Apr 16 10:21:11 2010 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0492D106566C; Fri, 16 Apr 2010 10:21:11 +0000 (UTC) (envelope-from bms@incunabulum.net) Received: from out2.smtp.messagingengine.com (out2.smtp.messagingengine.com [66.111.4.26]) by mx1.freebsd.org (Postfix) with ESMTP id C430B8FC08; Fri, 16 Apr 2010 10:21:10 +0000 (UTC) Received: from compute1.internal (compute1.internal [10.202.2.41]) by gateway1.messagingengine.com (Postfix) with ESMTP id CB044E66F9; Fri, 16 Apr 2010 06:21:09 -0400 (EDT) Received: from heartbeat2.messagingengine.com ([10.202.2.161]) by compute1.internal (MEProxy); Fri, 16 Apr 2010 06:21:09 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=messagingengine.com; h=message-id:date:from:mime-version:to:cc:subject:references:in-reply-to:content-type:content-transfer-encoding; s=smtpout; bh=hT/m9ijtTfBZHcfVsbwCtNCwXl0=; b=DxBEVCth4yeKeE+o6XDKqqNxAoT/JOHnGtVwdZ1o22u5GG1WkHOSSTZzF6LM+bh9PBK6vgX0O7u5jrkq7pKAIHK7x5Jzd+wFCK7mEdcch0zna6zH2QBbCHkU8Z/asIv2SBkXttr6Qee6s4bN/WDTFVpXQlvO5+MUzb5DgxtHKVo= X-Sasl-enc: fGz0AGuH8Y7teyjeGf7NBWZs2Vnfyi7kFHMp8eQoNJ2n 1271413269 Received: from anglepoise.lon.incunabulum.net (cpc2-dals7-0-0-cust253.hari.cable.virginmedia.com [82.35.112.254]) by mail.messagingengine.com (Postfix) with ESMTPSA id 300B937F86; Fri, 16 Apr 2010 06:21:09 -0400 (EDT) Message-ID: <4BC83A12.2080700@incunabulum.net> Date: Fri, 16 Apr 2010 11:21:06 +0100 From: Bruce Simpson User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.1.9) Gecko/20100406 Thunderbird/3.0.4 MIME-Version: 1.0 To: Alexander Leidinger References: <201004101205.o3AC5VGp074266@svn.freebsd.org> <4BC7486C.9010804@incunabulum.net> <20100416102318.16752py80bkf418g@webmail.leidinger.net> In-Reply-To: <20100416102318.16752py80bkf418g@webmail.leidinger.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r206452 - head/sys/netinet X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Apr 2010 10:21:11 -0000 On 04/16/10 09:23, Alexander Leidinger wrote: > >> IP multicast group membership is always scoped to physical links [1]. >> The 4.4BSD API originally used the "primary IP address" to identify >> each link. Unfortunately this is not a persistent identifier, >> especially so in the use-case which had problems. > > > Is/was this the reason why multicast does not work in jails? The above point is totally unrelated to jail. I think the problem with jail is the fact that to receive multicast, sockets normally need to be bound to INADDR_ANY. Obviously, jail changes socket behaviour in interesting ways. This may require refactoring udp_input() considerably. We use the 4.4BSD legacy LIST_FOREACH() loop to deliver, rather than using a fan-in map (which is the Windows/Solaris approach). Linux also has 4.4BSD semantics, but can work around this by examining the SO_BINDTODEVICE option in the same path.