From owner-freebsd-questions@freebsd.org Tue Oct 8 05:25:31 2019 Return-Path: Delivered-To: freebsd-questions@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id DF070138D96 for ; Tue, 8 Oct 2019 05:25:31 +0000 (UTC) (envelope-from SRS0=Cq2X=YB=mail.sermon-archive.info=doug@sermon-archive.info) Received: from mail.sermon-archive.info (sermon-archive.info [71.177.216.148]) by mx1.freebsd.org (Postfix) with ESMTP id 46nQmB5WSmz4NVt for ; Tue, 8 Oct 2019 05:25:30 +0000 (UTC) (envelope-from SRS0=Cq2X=YB=mail.sermon-archive.info=doug@sermon-archive.info) Received: from [10.0.1.251] (mini [10.0.1.251]) by mail.sermon-archive.info (Postfix) with ESMTPSA id 46nQm81Sp0z2fjQT; Mon, 7 Oct 2019 22:25:28 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\)) Subject: Re: Intermittent connectivity loss with em(4) From: Doug Hardie In-Reply-To: Date: Mon, 7 Oct 2019 22:25:27 -0700 Cc: freebsd-questions@freebsd.org Content-Transfer-Encoding: quoted-printable Message-Id: References: <94B563F6-55C4-46BC-BD79-5CC2AD86E6C1@mail.sermon-archive.info> <43f0decc-d459-4ded-dc46-c249bc8e24c9@pp.dyndns.biz> <094A1786-98A8-4CEF-A036-5809D9705EC8@mail.sermon-archive.info> To: =?utf-8?Q?Morgan_Wesstr=C3=B6m?= X-Mailer: Apple Mail (2.3445.104.11) X-Virus-Scanned: clamav-milter 0.101.2 at mail X-Virus-Status: Clean X-Rspamd-Queue-Id: 46nQmB5WSmz4NVt X-Spamd-Bar: - Authentication-Results: mx1.freebsd.org; dkim=none; spf=pass (mx1.freebsd.org: domain of SRS0=Cq2X=YB=mail.sermon-archive.info=doug@sermon-archive.info designates 71.177.216.148 as permitted sender) smtp.mailfrom=SRS0=Cq2X=YB=mail.sermon-archive.info=doug@sermon-archive.info X-Spamd-Result: default: False [-1.32 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; NEURAL_HAM_MEDIUM(-0.84)[-0.843,0]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:71.177.216.148]; MV_CASE(0.50)[]; MIME_GOOD(-0.10)[text/plain]; IP_SCORE(-0.16)[asn: 5650(-0.75), country: US(-0.05)]; NEURAL_HAM_LONG(-0.92)[-0.917,0]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RCPT_COUNT_TWO(0.00)[2]; RCVD_IN_DNSWL_NONE(0.00)[148.216.177.71.list.dnswl.org : 127.0.10.0]; FORGED_SENDER(0.30)[bc979@lafn.org,SRS0=Cq2X=YB=mail.sermon-archive.info=doug@sermon-archive.info]; RCVD_NO_TLS_LAST(0.10)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:5650, ipnet:71.177.216.0/23, country:US]; FROM_NEQ_ENVFROM(0.00)[bc979@lafn.org,SRS0=Cq2X=YB=mail.sermon-archive.info=doug@sermon-archive.info]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 Oct 2019 05:25:31 -0000 It sounds like your cable modem is not using NAT for the various = machines, but is using one local address for both. Hence, it depends on = the response to the arp requests which one will receive the packets. In = my experience you have to configure cable modems for the local IP = addresses of the machines on your network. However, I have only dealt = with a couple of cable modem connections. You might want to contact the = internet provider and explain the situation to them. They can probably = identify the cause. -- Doug > On 7 October 2019, at 08:56, Morgan Wesstr=C3=B6m = wrote: >=20 > On 2019-10-07 05:55, Doug Hardie wrote: >> Forgot to include, I use a lot of bge devices and some rl. However, = I just discovered one of the remote client's computers has 2 em nics. I = am running the ping test now on it. I did find the following in = messages: >> zgrep em /var/log/messages* >> /var/log/messages.6.gz:Sep 29 15:22:33 brain kernel: em0: link state = changed to DOWN >> /var/log/messages.6.gz:Sep 29 17:08:14 brain kernel: em0: link state = changed to UP >> /var/log/messages.6.gz:Sep 29 17:09:46 brain kernel: em0: link state = changed to DOWN >> /var/log/messages.6.gz:Sep 29 17:09:49 brain kernel: em0: link state = changed to UP >> The first outage was a complete outage to that site. I don't know = what caused it or how it got resolved. I never noticed the second one. >> The client has not been really thrilled with this machine. He had a = much better one, but it was too noisy and replaced it. >> Yet another idea: get mtr "my trace route". package mtr-nox11 and = use it to go to google. It is traceroute and ping combined. You can = use -i 60 with it also. >> -- Doug >=20 > Thank you for your suggestions, Doug. My suspicions right now points = to my cable provider. >=20 > I have two identical machines. One of them is always hooked up as my = router/firewall and while that one is in service I'm free to experiment = on the other. > Earlier this year I switched from an ADSL provider to a DOCSIS 3.0 = Cable provider. The ADSL provider used to give me 5 external IPs and I = never had any trouble running both machines simultaneously through the = ADSL modem. My cable provider gives me 4 IPs but this is the first time = I attempt to run both machines simultaneously through the cable modem. >=20 > Tcpdump shows a peculiar behaviour which is why my suspicions now = points to the cable provider. >=20 > While connectivity is established on my test router, tcpdump properly = shows all packets leaving and entering that machine. But as soon as = connectivity is lost, tcpdump suddenly starts showing packets that are = leaving the _other_ machine instead. It only shows the leaving packets = though, not the incoming ones but regardless I believe this behaviour = isn't normal. As soon as connectivity returns on my test machine, = tcpdump once again returns to only show the packets from that machine. > Connectivity is never affected on the main machine when this happens = and at some point I'll have to unplug it and only have the test machine = connected but I have quite a few services running on that machine so = it's painful to disconnect it, even for a short time. > My DOCSIS knowledge is very limited and I have no idea how I can test = for proper functionality of my cable modem. There are very few settings = in it, none that I find relevant to this problem and the logs don't show = any errors so I'm lost for now. >=20 > /Morgan > _______________________________________________ > freebsd-questions@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to = "freebsd-questions-unsubscribe@freebsd.org"