From owner-freebsd-stable Thu Nov 1 4:31:14 2001 Delivered-To: freebsd-stable@freebsd.org Received: from mikea.ath.cx (okc-65-30-192-11.mmcable.com [65.30.192.11]) by hub.freebsd.org (Postfix) with ESMTP id E792137B405 for ; Thu, 1 Nov 2001 04:31:08 -0800 (PST) Received: (from mikea@localhost) by mikea.ath.cx (8.11.6/8.11.1) id fA1CV4d09426; Thu, 1 Nov 2001 06:31:04 -0600 (CST) (envelope-from mikea) Date: Thu, 1 Nov 2001 06:31:04 -0600 From: mikea To: Graham Menhennitt Cc: freebsd-stable@FreeBSD.ORG Subject: Re: network interface dies randomly - ifconfig down then up fixes Message-ID: <20011101063104.C9373@mikea.ath.cx> References: <5.1.0.14.0.20011101223313.00a23670@mail.mckinn1.vic.optushome.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <5.1.0.14.0.20011101223313.00a23670@mail.mckinn1.vic.optushome.com.au>; from gmenhennitt@optushome.com.au on Thu, Nov 01, 2001 at 10:39:33PM +1100 Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Thu, Nov 01, 2001 at 10:39:33PM +1100, Graham Menhennitt wrote: > I have a Arris Cornerstone CM200 cable modem connected to my FreeBSD stable > (cvsupped last week) box via UTP into a NE2000 compatible ISA Ethernet > adaptor. The connection randomly dies. I can send pings out of it and see > the Activity LED flash on the modem but the FreeBSD box never sees any > replies. Doing "ifconfig ed1 down" followed by "ifconfig ed1 up" fixes it. > It's been happening for about the last two weeks (so it happened before the > most recent cvsup also). It could be your cable provider doing things on their network. I have found that they are fond of making changes during prime time daylight, rather than in the wee hours, and most of their changes require me to reset my cablemodem (power cycle). If your /var/log/messages shows things like your upstream gateway MAC address changing (I run arpwatch, so I see that), then that has a high probability of being the problem. If not, then you may need to run tcpdump continuously on that interface to catch the ACK and SYN packets. I do that, too, so that I can trace attacks, but I do computer security for a living and hence am a professional paranoid. -- Mike Andrews mikea@mikea.ath.cx Tired old sysadmin since 1964 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message