From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Greear Subject: More details on why received UDP packets are treated as errors? Date: Mon, 29 Jul 2013 11:21:31 -0700 Message-ID: <51F6B2AB.5050607@candelatech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit To: netdev Return-path: Received: from mail.candelatech.com ([208.74.158.172]:40145 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756182Ab3G2SVc (ORCPT ); Mon, 29 Jul 2013 14:21:32 -0400 Received: from [192.168.100.226] (firewall.candelatech.com [70.89.124.249]) (authenticated bits=0) by ns3.lanforge.com (8.14.2/8.14.2) with ESMTP id r6TILVVL002601 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Mon, 29 Jul 2013 11:21:31 -0700 Sender: netdev-owner@vger.kernel.org List-ID: We have a test case on 3.9.9+ (local patches applied) where sending from VETH interface, through peer VETH bridged (with our own emulator bridge module) to physical interface, which is then looped to another physical interface (B). The VETH and the wired B interface are sending UDP traffic to each other. Routing rules should be configured such that this all works appropriately. Replacing our bridging module with a user-space bridge has same behaviour. This setup works on the 3.7.y kernel, but we only get one-way traffic (B to VETH) on 3.9.9+. I sniffed the B port, and traffic appears to be sent and received properly (ie, no checksum errors, etc). But, our user-space app shows no received UDP frames on B, and netstat -s gives the output below. Is there any way to get more details about what these 'packet receive errors' are caused by using normal-ish tools? Udp: 6827 packets received 0 packets to unknown port received. 6172 packet receive errors 12964 packets sent 0 receive buffer errors 0 send buffer errors Tcp connections also fail to work, and I see these TCP stats. I'm sure not all of this is related to the problem at hand, but likely some of it is. Tcp: 81 active connections openings 11 passive connection openings 66 failed connection attempts 0 connection resets received 17 connections established 204643 segments received 229686 segments send out 465 segments retransmited 322 bad segments received. 70 resets sent Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com