From owner-freebsd-net@FreeBSD.ORG Wed Apr 20 06:45:35 2005 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 8AA9416A4CE; Wed, 20 Apr 2005 06:45:35 +0000 (GMT) Received: from relay.bestcom.ru (relay.bestcom.ru [217.72.144.5]) by mx1.FreeBSD.org (Postfix) with ESMTP id 9017B43D39; Wed, 20 Apr 2005 06:45:34 +0000 (GMT) (envelope-from glebius@FreeBSD.org) Received: from cell.sick.ru (root@cell.sick.ru [217.72.144.68]) by relay.bestcom.ru (8.13.1/8.12.9) with ESMTP id j3K6jRF9088044 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Wed, 20 Apr 2005 10:45:28 +0400 (MSD) (envelope-from glebius@FreeBSD.org) Received: from cell.sick.ru (smmsp@localhost [127.0.0.1]) by cell.sick.ru (8.13.1/8.12.8) with ESMTP id j3K6jPRJ001539 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 20 Apr 2005 10:45:27 +0400 (MSD) (envelope-from glebius@FreeBSD.org) Received: (from glebius@localhost) by cell.sick.ru (8.13.1/8.13.1/Submit) id j3JHE6bv000396; Tue, 19 Apr 2005 21:14:06 +0400 (MSD) (envelope-from glebius@FreeBSD.org) X-Authentication-Warning: cell.sick.ru: glebius set sender to glebius@FreeBSD.org using -f Date: Tue, 19 Apr 2005 21:14:06 +0400 From: Gleb Smirnoff To: Sam Leffler Message-ID: <20050419171406.GA378@cell.sick.ru> References: <20050419064747.GC734@cell.sick.ru> <4264D430.D39B81D0@freebsd.org> <20050419120324.GA5862@cell.sick.ru> <4264F4BC.4F3B57AE@freebsd.org> <20050419121141.GB5862@cell.sick.ru> <4264F7D4.F5A9775F@freebsd.org> <42652357.8020604@errno.com> Mime-Version: 1.0 Content-Type: text/plain; charset=koi8-r Content-Disposition: inline In-Reply-To: <42652357.8020604@errno.com> User-Agent: Mutt/1.5.6i X-Virus-Scanned: ClamAV version devel-20050125, clamav-milter version 0.80ff on relay.bestcom.ru X-Virus-Status: Clean cc: Andre Oppermann cc: net@FreeBSD.org Subject: Re: if_link_state_change() patch for review X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Apr 2005 06:45:35 -0000 On Tue, Apr 19, 2005 at 08:27:19AM -0700, Sam Leffler wrote: S> >change message will report either all state changes or those where at S> >the time of reporting the state changed relative to the last report. S> >The same assumption is true for the OpenIGPd we are working on at the S> >moment. S> S> It is possible with the change to defer the messages to have multiple S> changes coalesced. If an app is written to assume it receives notice of S> every change and it uses this to track internal state then it can get S> confused. The issue was whether or not to communicate any coalescing to S> applications so they can recognize that it's happened. In lieu of doing S> that I asked for a console printf so we could see if it ever happened in S> practice. Yes, all the time we are speaking about a theoretical issue. Let's see whether it can happen or not. I decided to go ahead with this change. S> >From an (routing) application point of view only effective state changes S> >are interesting and only those should be provided. S> > S> S> If an inteface does down, moves network, then comes back up and you only S> get the up event then you will likely do the wrong thing unless you have S> some other way of identifying what happened. I'm not convinced (yet) S> this cannot happen so am being cautious. In this case you will receive additional messages, not only RTM_IFINFO. Move network will also generate RTM_NEWADDR and RTM_DELADDR -- Totus tuus, Glebius. GLEBIUS-RIPN GLEB-RIPE