From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: Packet Corruption Support Date: Wed, 16 Aug 2006 15:59:58 -0700 Message-ID: <20060816155958.2598bdff@localhost.localdomain> References: <44E3A132.7090302@aston.ac.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: "netdev@vger.kernel.org" Return-path: Received: from smtp.osdl.org ([65.172.181.4]:44437 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S932313AbWHPXAH (ORCPT ); Wed, 16 Aug 2006 19:00:07 -0400 To: Ritesh Taank In-Reply-To: <44E3A132.7090302@aston.ac.uk> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Wed, 16 Aug 2006 23:50:26 +0100 Ritesh Taank wrote: > Hi there, > > I am currently using netem that has been packaged with my linux kernel > 2.6.17 (as part of the Knoppix 5.0.1 Boot CD), and the 'corrupt' > parameter is not being recognised as a valid argument. > > Having read many posts online, it appears that the Packet Corruption > feature should be supported from kernel versions 2.6.16 onwards. > > So I was wondering why my version does not support the corrupt feature? > > Are there any kernel versions out there that do support it? > > I was wondering if there was a way to patch my existing kernel do enable > the corruption feature? > > Any help/guidance is much appreciate. > > Thanks in advance too. > > Ritesh It was introduced with this change set. Author: Stephen Hemminger 2005-12-21 19:03:44 Committer: David S. Miller 2006-01-03 13:11:05 Parent: aa8751667dcd757dd9a711b51140adf181501c44 ([PKT_SCHED]: sch_netem: correctly order packets to be sent simultaneously) Child: 6d037a26f08711a222ed0d3d12b09e93eed7d3e8 ([PKT_SCHED]: Qdisc drop operation is optional) [PKT_SCHED] netem: packet corruption option Here is a new feature for netem in 2.6.16. It adds the ability to randomly corrupt packets with netem. A version was done by Hagen Paul Pfeifer, but I redid it to handle the cases of backwards compatibility with netlink interface and presence of hardware checksum offload. It is useful for testing hardware offload in devices. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller More likely the version if iproute2 utilities included with Knoppix is not up to date and doesn't understand the command line option.