From owner-freebsd-questions@freebsd.org Tue Jul 20 14:20:43 2021 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 97F7B66CB3E for ; Tue, 20 Jul 2021 14:20:43 +0000 (UTC) (envelope-from freebsd-lists-5@thismonkey.com) Received: from mail-01.thismonkey.com (mail-01.thismonkey.com [IPv6:2406:3400:35e:6602::a01:232]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "thismonkey.com", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4GTgqF4vZ2z4YSy for ; Tue, 20 Jul 2021 14:20:41 +0000 (UTC) (envelope-from freebsd-lists-5@thismonkey.com) Received: from mailhub-01.thismonkey.com (mailhub-01.thismonkey.com [IPv6:2406:3400:35e:6601:0:0:a01:11e]) by mail-01.thismonkey.com (8.15.2/8.15.2) with ESMTP id 16KEKNOe042892; Wed, 21 Jul 2021 00:20:23 +1000 (EST) (envelope-from freebsd-lists-5@thismonkey.com) X-TM-Via-MX: mailhub-01.thismonkey.com Received: from utility-01.thismonkey.com (utility-01.thismonkey.com [IPv6:2406:3400:35e:6601:0:0:a01:120]) by mailhub-01.thismonkey.com (8.15.2/8.15.2) with ESMTPS id 16KEKNSf020232 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Wed, 21 Jul 2021 00:20:23 +1000 (AEST) (envelope-from freebsd-lists-5@thismonkey.com) Received: from utility-01.thismonkey.com (localhost [127.0.0.1]) by utility-01.thismonkey.com (8.16.1/8.16.1) with ESMTP id 16KEKNUR015858; Wed, 21 Jul 2021 00:20:23 +1000 (EST) (envelope-from freebsd-lists-5@thismonkey.com) Received: (from root@localhost) by utility-01.thismonkey.com (8.16.1/8.16.1/Submit) id 16KEKMZg015840; Wed, 21 Jul 2021 00:20:22 +1000 (EST) (envelope-from freebsd-lists-5@thismonkey.com) Date: Wed, 21 Jul 2021 00:20:21 +1000 From: Scott To: Mel Pilgrim Cc: freebsd-questions@freebsd.org Subject: Re: Specifying IPv6 off-link for a subnet Message-ID: Mail-Followup-To: Mel Pilgrim , freebsd-questions@freebsd.org References: <5ea688b3-79b9-8a28-0430-5a4651207ae0@bluerosetech.com> <010afd33-d7e5-b8b5-229e-823aa007a045@bluerosetech.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <010afd33-d7e5-b8b5-229e-823aa007a045@bluerosetech.com> X-Virus-Scanned: clamav-milter 0.102.2 at mail-01.thismonkey.com X-Virus-Status: Clean X-Rspamd-Queue-Id: 4GTgqF4vZ2z4YSy X-Spamd-Bar: --- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=pass (policy=none) header.from=thismonkey.com; spf=pass (mx1.freebsd.org: domain of freebsd-lists-5@thismonkey.com designates 2406:3400:35e:6602::a01:232 as permitted sender) smtp.mailfrom=freebsd-lists-5@thismonkey.com X-Spamd-Result: default: False [-3.80 / 15.00]; MID_RHS_MATCH_FROM(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[2406:3400:35e:6602::a01:232:from]; ARC_NA(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+mx]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; SPAMHAUS_ZRD(0.00)[2406:3400:35e:6602::a01:232:from:127.0.2.255]; RCVD_COUNT_THREE(0.00)[4]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_HAM_SHORT(-1.00)[-0.999]; RCPT_COUNT_TWO(0.00)[2]; DMARC_POLICY_ALLOW(-0.50)[thismonkey.com,none]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:10143, ipnet:2406:3400:340::/42, country:AU]; RCVD_TLS_LAST(0.00)[]; MAILMAN_DEST(0.00)[freebsd-questions] X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 20 Jul 2021 14:20:43 -0000 On Mon, Jul 19, 2021 at 12:40:35PM -0700, Mel Pilgrim wrote: > On 2021-07-18 17:07, Scott wrote: > > On Wed, Jul 07, 2021 at 07:43:48PM -0700, Mel Pilgrim wrote: > >> On 2021-07-05 8:45, Scott wrote: > >>> I have manually configured IPv6 on the interfaces: > >>> ifconfig_vmx0_ipv6="inet6 xx::yy prefer_source accept_rtadv -autoconf no_radr" > [...] > >>> Here's the received RA: > [...] > >>> prefix info option (3), length 32 (4): xx::/64, Flags [none], valid > >>> time 3600s, pref. time 60s > >>> > >>> Note that there is no L flag set, so the prefix is off-link. > >> > >> If set, the L flag indicates the prefix can be used for on-link > >> determination. But if the L bit is unset, the PIO isn't making any > >> assertion about the prefix being on-link or off-link. More importantly, > >> a host must not use a PIO with L=0 to conclude a prefix is off-link. > >> > >> IOW, it is correct for a host to do nothing when it receives an RA PIO > >> with no flags for an already-configured prefix. > > > > so for the case of manually addressed devices on a private vLAN/IPPL there > > must be a way to specify that the configured prefix is not on-Link. > > Yes, by not configuring that prefix. Numbering vmx0 into xx::/64 made > xx::/64 on-link by definition. > > This seems like too intuitive of an answer, though. Can you step back > and explain what you need to do at a higher level? > My need is pretty simple: to have FreeBSD servers with an IPv6 stack operating correctly on a private vLAN (IPPL). Specifically an isolated private vLAN. In IPv6 (as I understand it), this should be done by specifying that the prefix/subnet of the configured address is not on-link, and therefore should *always* use the router as the next hop. (Similar to an NBMA network). I have this working for IPv4 - which uses different mechanisms such as local proxy ARP on the router (such mechanisms do no apply to v6). Thanks