From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ob0-x234.google.com (mail-ob0-x234.google.com [IPv6:2607:f8b0:4003:c01::234]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 113D121F34A for ; Mon, 17 Nov 2014 08:10:39 -0800 (PST) Received: by mail-ob0-f180.google.com with SMTP id wp4so4195256obc.11 for ; Mon, 17 Nov 2014 08:10:38 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=2pSXEyiCzrEBtqpk15a3+Qy/wxwLnykvIzQSgckiy4g=; b=lpunijvEafiYnbVvB+JQlRnFfnyomrSlMXA82TVWH1dnjKV5jzIPczuFUKUEWYj/Pq E/pByzSW8CHszo9d0Fu0iuBlTLJu57C5NUAc1jy/Fc6ilKpM5hg+WsIVklayi4uOmJ0v 685luhf3t5Zlg57G+nJMEuHfPV66vM5Cd/G3BzjBXvMHeBwcALf1wspALldiyp7h+PPv 33HOQYJj+4cln3kxnFe5Jlp94aQcqMvm2cB03hi9yyFRZarQYpGpYnsZeOpwXgik460O EZ9Xt/dYF43BlWzpFNfXY4ASrQWlp/5PzTY1gciYCnfjWUeGydkCAENZPHEPpCb7hY2c IMWw== MIME-Version: 1.0 X-Received: by 10.202.177.65 with SMTP id a62mr1811240oif.92.1416240638371; Mon, 17 Nov 2014 08:10:38 -0800 (PST) Received: by 10.202.227.211 with HTTP; Mon, 17 Nov 2014 08:10:38 -0800 (PST) Date: Mon, 17 Nov 2014 08:10:38 -0800 Message-ID: From: Dave Taht To: "cerowrt-devel@lists.bufferbloat.net" , "babel-users@lists.alioth.debian.org" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: [Cerowrt-devel] dealing with soft default gateway failures 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, 17 Nov 2014 16:11:08 -0000 I have a couple situations where the default gw fails for some reason or another and I would like to sanely fail over to another router. In two case, the dsl modem in place periodically loses connectivity and should fail over to the cable modem in place... and in another case I had plugged in a cable modem that supplied a default route but did not actually have connectivity to the internet itself, but have multiple cable modems on the same network each with a babel interface to them, supplying default routes where appropriate. I filed a request for babel-pinger here, but it doesnt quite do what I want. I would like something more responsive. https://github.com/openwrt-routing/packages/issues/65 Rather than constantly pinging at a slow rate, having an iptables rule that looked for ICMP unreachable messages and fired up a =C2=A8checker=C2= =A8 process to see if basic connectivity had been lost (both for ipv4 and ipv6) seems like a solution that is faster and lighter weight and more robust. Instead of trusting the default dhcp route, do something to check that the path is good, first, instead. --=20 Dave T=C3=A4ht thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_Talks