From owner-freebsd-hackers Thu Dec 6 5:47: 7 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from hoolan.org (db217.csie.ncu.edu.tw [140.115.50.217]) by hub.freebsd.org (Postfix) with ESMTP id B9A2337B419 for ; Thu, 6 Dec 2001 05:47:01 -0800 (PST) Received: from localhost (jeff@localhost [127.0.0.1]) by hoolan.org (8.11.6/8.11.6) with ESMTP id fB6Dknu88956 for ; Thu, 6 Dec 2001 21:46:53 +0800 (CST) (envelope-from jeff@hoolan.org) Date: Thu, 6 Dec 2001 21:46:49 +0800 (CST) From: Yung-Sheng Tang X-Sender: jeff@hoolan.org To: freebsd-hackers@freebsd.org Subject: UDP checksum error after encapsulating multicast packet Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG I am setting up a multicast router. Recompiling kernel with MROUTING option and enabling mrouted are done. Basically, my multicast AP runs well, but if that AP and mrouted run on the same machine, forwarded packets would get udp checksum error. Here is the result from tcpdump: 18:27:12.968167 192.9.200.127.1399 > 224.2.3.4.1234: [udp sum ok] udp 16 (ttl 16, id 38554, len 44) 4500 002c 969a 0000 1011 a897 c009 c87f e002 0304 0577 04d2 0018 22c5 ea02 0400 3c0f 4401 0001 3145 c7c6 0000 18:27:12.968185 192.9.200.127 > 150.9.120.183: 192.9.200.127.1399 > 224.2.3.4.1234: [bad udp cksum bb7!] udp 16 (ttl 15, id 38554, len 44) (ttl 64, id 38555, len 64) 4500 0040 969b 0000 4004 4cd5 c009 c87f 9609 78b7 4500 002c 969a 0000 0f11 a997 c009 c87f e002 0304 0577 04d2 0018 6bb9 ea02 0400 3c0f 4401 0001 3145 c7c6 0000 Did I make some mistake? Thank you for your attention. -- Yung-Sheng Jeff Tang To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message