From nobody Mon Apr 04 03:37:32 2022 X-Original-To: freebsd-net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id C4FC71A494A6 for ; Mon, 4 Apr 2022 03:37:37 +0000 (UTC) (envelope-from brett@lariat.net) Received: from mail.lariat.net (mail.lariat.net [66.62.230.51]) by mx1.freebsd.org (Postfix) with ESMTP id 4KWxL90sfKz3Qdm for ; Mon, 4 Apr 2022 03:37:37 +0000 (UTC) (envelope-from brett@lariat.net) Received: from Toshi.lariat.net (IDENT:ppp1000.lariat.net@localhost [127.0.0.1]) by mail.lariat.net (8.9.3/8.9.3) with ESMTP id VAA10654 for ; Sun, 3 Apr 2022 21:37:33 -0600 (MDT) Message-Id: <202204040337.VAA10654@mail.lariat.net> X-Mailer: QUALCOMM Windows Eudora Version 7.1.0.9 Date: Sun, 03 Apr 2022 21:37:32 -0600 To: freebsd-net@FreeBSD.org From: freebsd-net@brettglass.com Subject: Wireguard, MTUs, and jumbo packets List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@freebsd.org Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed X-Rspamd-Queue-Id: 4KWxL90sfKz3Qdm X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of brett@lariat.net designates 66.62.230.51 as permitted sender) smtp.mailfrom=brett@lariat.net X-Spamd-Result: default: False [-2.40 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; R_SPF_ALLOW(-0.20)[+a:c]; MV_CASE(0.50)[]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-net@freebsd.org]; TO_DN_NONE(0.00)[]; RCPT_COUNT_ONE(0.00)[1]; NEURAL_HAM_LONG(-1.00)[-1.000]; DMARC_NA(0.00)[brettglass.com]; TO_MATCH_ENVRCPT_ALL(0.00)[]; NEURAL_HAM_SHORT(-1.00)[-1.000]; FROM_NO_DN(0.00)[]; MLMMJ_DEST(0.00)[freebsd-net]; FORGED_SENDER(0.30)[freebsd-net@brettglass.com,brett@lariat.net]; RCVD_NO_TLS_LAST(0.10)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:19092, ipnet:66.62.228.0/22, country:US]; FROM_NEQ_ENVFROM(0.00)[freebsd-net@brettglass.com,brett@lariat.net]; RCVD_COUNT_TWO(0.00)[2] X-ThisMailContainsUnwantedMimeParts: N Everyone: Would like to use the new Wireguard implementation, but need to know what it does to MTUs. I'd like a full 1500 byte MTU through the VPN tunnel, but this means that the packets that are sent between the client and server have to be BIGGER than 1500 bytes. It takes a special feature to allow PPPoE to negotiate a larger MTU (see RFC 4638), and other PPP-based protocols such as L2TP wont do it at all. But what happens in Wireguard? I can find no documentation on this topic, so assistance would be appreciated. --Brett Glass