From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9353FC432BE for ; Fri, 27 Aug 2021 21:55:21 +0000 (UTC) Received: from lists.zx2c4.com (lists.zx2c4.com [165.227.139.114]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D2AB460C40 for ; Fri, 27 Aug 2021 21:55:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org D2AB460C40 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=pineview.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.zx2c4.com Received: by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTP id 47baa804; Fri, 27 Aug 2021 21:54:23 +0000 (UTC) Received: from mail.pineview.net (mail.pineview.net [203.33.246.11]) by lists.zx2c4.com (ZX2C4 Mail Server) with ESMTPS id 6a6409b0 (TLSv1.3:AEAD-AES256-GCM-SHA384:256:NO) for ; Fri, 27 Aug 2021 21:54:19 +0000 (UTC) Received: from airtime.pineview.net (airtime.pineview.net [203.33.246.51]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits)) (No client certificate requested) by mail.pineview.net (Postfix) with ESMTPSA id 2A39D8002B; Sat, 28 Aug 2021 07:24:16 +0930 (ACST) Subject: Re: [Warning: DMARC Fail Email] Re: ipv6 connexion fail - ipv4 OK To: Roman Mamedov Cc: Daniel , wireguard@lists.zx2c4.com References: <20210827211412.3ed5f170@natsu> <3ec547c6-c846-e5be-e276-ace7862f5cb7@tootai.net> <34d4341c-98be-b754-af8e-c7097bc21aac@pineview.net> <20210828024454.1766744f@natsu> From: Mike O'Connor Message-ID: <18028d40-be81-f80b-31a2-d9ba15486dff@pineview.net> Date: Sat, 28 Aug 2021 07:24:16 +0930 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 MIME-Version: 1.0 In-Reply-To: <20210828024454.1766744f@natsu> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-BeenThere: wireguard@lists.zx2c4.com X-Mailman-Version: 2.1.30rc1 Precedence: list List-Id: Development discussion of WireGuard List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: wireguard-bounces@lists.zx2c4.com Sender: "WireGuard" root@gw:~# ping -M do -s 1472 13.17.1.2 PING 103.127.123.217 (13.17.1.2) 1472(1500) bytes of data. 1480 bytes from 13.17.1.2: icmp_seq=1 ttl=60 time=7.93 ms Link can transmit a max of 1500 bytes as seen above. Pinging a LAN segment has the same limit. ie PC to PC has the same result. Mike On 28/8/21 7:14 am, Roman Mamedov wrote: > On Sat, 28 Aug 2021 07:05:45 +0930 > Mike O'Connor wrote: > >> On a 1500 link I'm having to use 1280 to get ipv6 to successfully go >> over a wireguard link. > Then it is not a true 1500 MTU link, something in-between drops packets at a > lower bar. Or maybe not all of them, but just UDP, for example. > > But yeah, 1280 is worth trying as well, maybe Daniel has a similar issue. > > As for me I am using MTU 1412 WG over IPv6 on a 1492 MTU underlying link just > fine. > >> I really think wireguard should be able to fragment and send via >> multiply UDP packets. > It is able to, as long as the underlying link MTU is set to a correct value > (i.e. where largest-sized packets actually go through, and not get silently > dropped). >