From owner-freebsd-net@freebsd.org Fri Feb 19 02:29:46 2021 Return-Path: Delivered-To: freebsd-net@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 0F017537655 for ; Fri, 19 Feb 2021 02:29:46 +0000 (UTC) (envelope-from bc979@lafn.org) Received: from mailman.nyi.freebsd.org (mailman.nyi.freebsd.org [IPv6:2610:1c1:1:606c::50:13]) by mx1.freebsd.org (Postfix) with ESMTP id 4DhbBd6Jgzz4kNd for ; Fri, 19 Feb 2021 02:29:45 +0000 (UTC) (envelope-from bc979@lafn.org) Received: by mailman.nyi.freebsd.org (Postfix) id D6B22537654; Fri, 19 Feb 2021 02:29:45 +0000 (UTC) Delivered-To: net@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 D67E9537804 for ; Fri, 19 Feb 2021 02:29:45 +0000 (UTC) (envelope-from bc979@lafn.org) Received: from mail.sermon-archive.info (sermon-archive.info [71.177.216.148]) by mx1.freebsd.org (Postfix) with ESMTP id 4DhbBc6rhvz4kR2 for ; Fri, 19 Feb 2021 02:29:44 +0000 (UTC) (envelope-from bc979@lafn.org) Received: from [10.0.1.251] (mini [10.0.1.251]) by mail.sermon-archive.info (Postfix) with ESMTPSA id 4DhbBT5GPrz2fjPN for ; Thu, 18 Feb 2021 18:29:37 -0800 (PST) From: Doug Hardie Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.60.0.2.21\)) Subject: IPv6 Fragmentation Message-Id: Date: Thu, 18 Feb 2021 18:29:37 -0800 To: "net@freebsd.org" X-Mailer: Apple Mail (2.3654.60.0.2.21) X-Virus-Scanned: clamav-milter 0.103.0 at mail X-Virus-Status: Clean X-Rspamd-Queue-Id: 4DhbBc6rhvz4kR2 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of bc979@lafn.org designates 71.177.216.148 as permitted sender) smtp.mailfrom=bc979@lafn.org X-Spamd-Result: default: False [-2.44 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; FROM_HAS_DN(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[71.177.216.148:from]; MV_CASE(0.50)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[net@freebsd.org]; DMARC_NA(0.00)[lafn.org: no valid DMARC record]; RCPT_COUNT_ONE(0.00)[1]; SPAMHAUS_ZRD(0.00)[71.177.216.148:from:127.0.2.255]; R_SPF_ALLOW(-0.20)[+ip4:71.177.216.148/32]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.74)[-0.744]; TO_DN_EQ_ADDR_ALL(0.00)[]; RCVD_NO_TLS_LAST(0.10)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:5650, ipnet:71.177.216.0/23, country:US]; RCVD_COUNT_TWO(0.00)[2]; MAILMAN_DEST(0.00)[net] X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 19 Feb 2021 02:29:46 -0000 I don't know if this is a feature or a bug. On FreeBSD 9, the following = ping worked: ping6 -s 5000 -b 6000 fe80::213:72ff:fec3:180f%dc0 It had to be stopped, but it returned the number of ping responses = received along with statistics. With FreeBSD 12.2 and 13.0-BETA2, it returns 100% packet loss. tcpdump = shows that it properly fragments the data, sends it, the other end = receives it and sends back the ACKs. The ACKs are received, but somehow = ping doesn't find out that the packets were received. Without the -s and -b arguments, it works and you get 100% packets = received. -- Doug