Return-Path: X-Original-To: dnsop@ietfa.amsl.com Delivered-To: dnsop@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 61016C1519AD; Fri, 5 Jul 2024 03:51:18 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -2.264 X-Spam-Level: X-Spam-Status: No, score=-2.264 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, NICE_REPLY_A=-0.355, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01] autolearn=unavailable autolearn_force=no Received: from mail.ietf.org ([50.223.129.194]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Zt4-38clTLyQ; Fri, 5 Jul 2024 03:51:17 -0700 (PDT) Received: from mail.netability.ie (mail.netability.ie [46.182.8.5]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 97E34C14CEED; Fri, 5 Jul 2024 03:51:15 -0700 (PDT) Received: from crumpet.local (unknown [IPv6:2a00:ca0:2028:a018:156c:9630:d4af:18bb]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.netability.ie (Postfix) with ESMTPSA id 3A9CEB061F; Fri, 5 Jul 2024 11:51:05 +0100 (IST) To: Philip Homburg References: <171957523370.366291.478718063778248894@dt-datatracker-ff7f57fbb-ch6dm> <491D5E6C-41CC-4E63-B10F-2E8F4BDC2513@apnic.net> <2880837.88bMQJbFj6@heater.srcl.tisf.net> From: Nick Hilliard Message-ID: Date: Fri, 5 Jul 2024 11:50:58 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.16; rv:52.0) Gecko/20100101 PostboxApp/7.0.60 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Message-ID-Hash: 27H46HJXEF5A4SNBMNUAVOU3DHKFXV4J X-Message-ID-Hash: 27H46HJXEF5A4SNBMNUAVOU3DHKFXV4J X-MailFrom: nick@foobar.org X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-dnsop.ietf.org-0; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: v6ops@ietf.org, Paul Vixie , dnsop X-Mailman-Version: 3.3.9rc4 Precedence: list Subject: =?utf-8?q?=5BDNSOP=5D_Re=3A_=5Bv6ops=5D_Re=3A_Re=3A_Fwd=3A_New_Version_Notif?= =?utf-8?q?ication_-_draft-ietf-dnsop-avoid-fragmentation-18=2Etxt?= List-Id: IETF DNSOP WG mailing list Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Philip Homburg wrote on 05/07/2024 11:01: > Can we go back to reality? There is no PMTU discovery for DNS replies > over UDP that works at scale. It doesn't work, it never worked. specifically, short of implementing end-to-end circuits, it can't work reliably. There is no way for an endpoint to detect intermediate topology changes between itself and another endpoint, short of heuristic and/or post-hoc interpretation of what's going on in the data plane. Nick