From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f175.google.com (mail-wi0-f175.google.com [209.85.212.175]) (using TLSv1 with cipher RC4-MD5 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 89F89200174 for ; Mon, 19 Mar 2012 12:41:24 -0700 (PDT) Received: by wibhn6 with SMTP id hn6so3770108wib.10 for ; Mon, 19 Mar 2012 12:41:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; bh=AtIbG8mpxid1P2eWRi9sJxE95fEVngboyyv5/v4jIFU=; b=VAno/ZCK5P2V7A+xGrjExrJPwgOnvnPJ/R3wDPQytoU2Ar3dDJF06zV/EXi6WcjTwk rNYPeU4ue2LcSk97sowVbjtHvwC8o1Hmd90GR0RWvocnzs9A1madOTCU9HfKUaiwjHpc Rgflis78I9plnwZ3CgDRkXgvefdNZdP0Idq25ZtAsDFDB6p7rB/wDnQPArPEt9Nmbiri Z6NfWad1K7t89S7jEWu2mUOTiySLHrXqEAPmBaVBVUtTr1NFmltxsqIqEo2Y5K++8nl6 ncBGMRDqJwhYFFIZxMWtvgrBN29xg/2NhHyaThq/CfoooxJ/2ZgPCCRcovXnWb3kSA2w jqew== MIME-Version: 1.0 Received: by 10.180.88.67 with SMTP id be3mr22279309wib.20.1332186082205; Mon, 19 Mar 2012 12:41:22 -0700 (PDT) Received: by 10.223.132.208 with HTTP; Mon, 19 Mar 2012 12:41:22 -0700 (PDT) In-Reply-To: References: Date: Mon, 19 Mar 2012 19:41:22 +0000 Message-ID: From: Robert Bradley To: cerowrt-devel@lists.bufferbloat.net Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Cerowrt-devel] mdns reflector issues on ipv6/babel routing through nat. X-BeenThere: cerowrt-devel@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: Development issues regarding the cerowrt test router project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 19 Mar 2012 19:41:25 -0000 On 18 March 2012 21:22, Dave Taht wrote: > > Once you get to a few routers, a few deep, (3 in series in this case, > 9 overall), the avahi mdns proxy starts to malfunction over ipv6, and > I ended up with a rather nasty broadcast storm. > Now this is across like 5 different versions of cerowrt, but it would > not surprise me that this is a =C2=A0generic problem with avahi on ipv6, > and/or a symptom of the brain-damaged-ness of mdns in the first place. > I thought that broadcast storms were a known issue with Avahi's mdns reflector. The man pages for avahi-daemon.conf (http://linux.die.net/man/5/avahi-daemon.conf) have this to say: "Make sure to not run multiple reflectors between the same networks, this might cause them to play Ping Pong with mDNS packets." I think the official answer for mesh networks (and subnetted networks in general) is to switch to wide-area Bonjour - in other words, dynamically publishing records to a real DNS server.=C2=A0 Avahi had problems with publishing records in the past, but as far as I can tell those have been resolved. One problem with using Wide-Area Bonjour is configuration. As far as I can tell, you have to specify a specific (non-.local) domain for wide-area browsing, and there is no good automated solution for home users. For Avahi, this means editing /etc/avahi/avahi-daemon.conf and setting the "domain-name" and "browse-domains" options. Setting this up on OS X and Windows is difficult for most home users, and involves either installing the SDK or editing the Registry or configuration files by hand. A set of DHCP options (similar to those for WINS and NBT on Windows) for disabling mdns and setting up wide-area Bonjour would be useful... Worse than that, though, some sites (e.g. http://www.afp548.com/article.php?story=3D20090225001154457) suggest that Apple's Bonjour daemon will only register global IP addresses with the DNS server, and not private addresses. This makes the whole thing worse than useless for CeroWRT! Solutions to this? - Give up on cross-subnet publishing entirely. - Write a variant of Avahi's mDNS reflector that listens to local mDNS traffic and reissues queries over unicast DNS. Any local record announcements it sees would need to be registered with the unicast DNS server too. - Get the DHCP server to add initial SRV/TXT records to the DNS server, so you're not dependent on OS X doing the right thing. mDNSResponder can then update these records later if it feels like it. The disadvantage is that you're either reporting services that may not exist, or are not reporting some services. - Advertise global IPv6 addresses throughout the mesh? This might work, although Windows tends to object to mDNS over IPv6... -- Robert Bradley