From owner-freebsd-current@FreeBSD.ORG Thu Aug 23 14:27:48 2012 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 4ED661065673 for ; Thu, 23 Aug 2012 14:27:48 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from bigwig.baldwin.cx (bigknife-pt.tunnel.tserv9.chi1.ipv6.he.net [IPv6:2001:470:1f10:75::2]) by mx1.freebsd.org (Postfix) with ESMTP id 239988FC14 for ; Thu, 23 Aug 2012 14:27:48 +0000 (UTC) Received: from jhbbsd.localnet (unknown [209.249.190.124]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 85C50B964; Thu, 23 Aug 2012 10:27:47 -0400 (EDT) From: John Baldwin To: Peter Jeremy Date: Thu, 23 Aug 2012 08:02:45 -0400 User-Agent: KMail/1.13.5 (FreeBSD/8.2-CBSD-20110714-p17; KDE/4.5.5; amd64; ; ) References: <20120821095527.GA33206@hell.ukr.net> <201208221535.01598.jhb@freebsd.org> <20120823013534.GA31015@server.rulingia.com> In-Reply-To: <20120823013534.GA31015@server.rulingia.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Message-Id: <201208230802.45030.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Thu, 23 Aug 2012 10:27:47 -0400 (EDT) Cc: YongHyeon PYUN , freebsd-current@freebsd.org Subject: Re: dhclient cause up/down cycle after 239356 ? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 23 Aug 2012 14:27:48 -0000 On Wednesday, August 22, 2012 9:35:34 pm Peter Jeremy wrote: > On 2012-Aug-22 15:35:01 -0400, John Baldwin wrote: > >Hmm. Perhaps we could use a debouncer to ignore "short" link flaps? Kind of > >gross (and OpenBSD doesn't do this). For now this change basically ignores > >link up events if they occur with 5 seconds of the link down event. The 5 is > >hardcoded which is kind of yuck. > > I'm also a bit concerned about this for similar reasons to adrian@. > We need to distinguish between short link outages caused by (eg) a > switch admin reconfiguring the switch (which needs the lease to be > re-checked) and those caused by broken NICs which report link status > changes when they are touched. Maybe an alternative is to just ignore > link flaps when they occur within a few seconds of a script_go(). > (And/or make the ignore timeout configurable). > > Apart from fxp(4), does anyone know how many NICs are similarly > broken? > > Does anyone know why this issue doesn't bite OpenBSD? Does it have > a work-around to avoid resetting the link, not report link status > changes or just no-one has noticed the issue? To be clear, I don't like this hack. If there is a way to fix this in the driver (e.g. not report the link state changes during a reset) that would be far preferable. -- John Baldwin