From owner-freebsd-questions@freebsd.org Thu Jun 20 02:58:08 2019 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id D695215D1BD9 for ; Thu, 20 Jun 2019 02:58:07 +0000 (UTC) (envelope-from roberthuff@rcn.com) Received: from smtp.rcn.com (smtp.rcn.com [69.168.97.78]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id E39368E391 for ; Thu, 20 Jun 2019 02:58:06 +0000 (UTC) (envelope-from roberthuff@rcn.com) DKIM-Signature: v=1; a=rsa-sha1; d=rcn.com; s=20180516; c=relaxed/simple; q=dns/txt; i=@rcn.com; t=1560999485; h=From:Subject:Date:To:MIME-Version:Content-Type; bh=+5Ymq7hzRvugjRfCDROyMBRgByc=; b=a9d+h2nx2kRc6Gg3lLQrT54n8OcfW2lLAFS341KcmpnRrM5yCz05/7zOH4olpkdy YV1T/stcrvxNyikno8D5o+jRkOYB/ebjcdW1XtRPCmNuXJmjX8YLTCpV+XItpq1N 7WhG9G85oT8DEsuSx0A3+zTHSHXhaGsnKz/l/QXO4I+A+z4H2ojmpt5OIKneI9se ylP+ts2W5dhEKCNf9/wlCGFN4aB34vG+hz0JaWjFtmmTN1f6FNxDV4XbdICh2Xa6 +cZCle9LdvfpuBKIBCtFXSio5idWRosLxSpk8dHOLnBVPW+g+ZKX0wxbzzsY4abr 9kurmv+JJrX5UxW27bzRXA==; X_CMAE_Category: , , X-CNFS-Analysis: v=2.2 cv=aKGykv1m c=1 sm=1 tr=0 a=9TgA2UwI6Wy+6BV4wQM/cQ==:117 a=9TgA2UwI6Wy+6BV4wQM/cQ==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=KGjhK52YXX0A:10 a=kj9zAlcOel0A:10 a=XRQyMpdBKAEA:10 a=dq6fvYVFJ5YA:10 a=48faUk6PgeAA:10 a=TeW0tiTjp0bHKsuJq68A:9 a=CjuIK1q_8ugA:10 X-CM-Score: 0 X-Scanned-by: Cloudmark Authority Engine X-Authed-Username: cm9iZXJ0aHVmZkByY24uY29t Authentication-Results: smtp03.rcn.cmh.synacor.com header.from=roberthuff@rcn.com; sender-id=softfail Authentication-Results: smtp03.rcn.cmh.synacor.com smtp.user=roberthuff; auth=pass (PLAIN) Received: from [209.6.230.48] ([209.6.230.48:41368] helo=jerusalem.litteratus.org.litteratus.org) by smtp.rcn.com (envelope-from ) (ecelerity 3.6.25.56547 r(Core:3.6.25.0)) with ESMTPSA (cipher=AES256-GCM-SHA384) id B8/D6-13517-D36FA0D5; Wed, 19 Jun 2019 22:58:05 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <23818.63036.888460.410557@jerusalem.litteratus.org> Date: Wed, 19 Jun 2019 22:58:04 -0400 From: Robert Huff To: "Rodney W. Grimes" Cc: Robert Huff , freebsd-net , FreeBSD Questions Mailing List , "Ronald F. Guilmette" Subject: Re: Eliminating IPv6 (?) In-Reply-To: <201906192322.x5JNMxpK020489@gndrsh.dnsmgr.net> References: <23818.36263.312034.714296@jerusalem.litteratus.org> <201906192322.x5JNMxpK020489@gndrsh.dnsmgr.net> X-Mailer: VM 8.2.0b under 26.2 (amd64-portbld-freebsd13.0) X-Rspamd-Queue-Id: E39368E391 X-Spamd-Bar: ------- Authentication-Results: mx1.freebsd.org; dkim=pass header.d=rcn.com header.s=20180516 header.b=a9d+h2nx; dmarc=pass (policy=none) header.from=rcn.com; spf=pass (mx1.freebsd.org: domain of roberthuff@rcn.com designates 69.168.97.78 as permitted sender) smtp.mailfrom=roberthuff@rcn.com X-Spamd-Result: default: False [-7.87 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_DKIM_ALLOW(-0.20)[rcn.com:s=20180516]; RCVD_TLS_ALL(0.00)[]; FROM_HAS_DN(0.00)[]; R_SPF_ALLOW(-0.20)[+ip4:69.168.97.0/24]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; IP_SCORE(-2.77)[ip: (-9.31), ipnet: 69.168.97.0/24(-4.59), asn: 36271(0.08), country: US(-0.06)]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; RCPT_COUNT_FIVE(0.00)[5]; DWL_DNSWL_LOW(-1.00)[rcn.com.dwl.dnswl.org : 127.0.5.1]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; DKIM_TRACE(0.00)[rcn.com:+]; MX_GOOD(-0.01)[cached: mx.rcn.com]; DMARC_POLICY_ALLOW(-0.50)[rcn.com,none]; NEURAL_HAM_SHORT(-0.99)[-0.989,0]; RCVD_IN_DNSWL_LOW(-0.10)[78.97.168.69.list.dnswl.org : 127.0.5.1]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:36271, ipnet:69.168.97.0/24, country:US]; RCVD_COUNT_TWO(0.00)[2]; SUBJECT_HAS_QUESTION(0.00)[] 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: Thu, 20 Jun 2019 02:58:08 -0000 Rodney W. Grimes writes: > > Wider question: > > Say I'm running a system with both IPv4 and IPv6 enabled. > > Stuff Happens(tm) and I want to completely disable IPv6 for some > > indefinite but temporary period - not chamge any configuration > > settings or firewall rules, but just have the code finish processing > > current packets (or not) and then ignore further traffic. There will > > be consequences; I'm prepared to accept them. > > Is there a single master switch - a sysctl, perhaps, or something > > in /etc/rc.d - that lets me do that? > > You do raise a very valid point. > > ipfw add 1 deny ipv6 from any to any > > That is about the only "master" switch I can think of that would > be very effective. Ywah ... but that violates the initial constraint. Respectfully, Robert Huff