From owner-freebsd-questions Thu Sep 27 0: 2:56 2001 Delivered-To: freebsd-questions@freebsd.org Received: from mip.co.za (puck.mip.co.za [209.212.106.44]) by hub.freebsd.org (Postfix) with ESMTP id 4ACA637B415 for ; Thu, 27 Sep 2001 00:02:48 -0700 (PDT) Received: from patrick (patrick.mip.co.za [10.3.13.181]) by mip.co.za (8.9.3/8.9.3) with SMTP id JAA50575; Thu, 27 Sep 2001 09:02:32 +0200 (SAST) (envelope-from patrick@mip.co.za) From: "Patrick O'Reilly" To: "Harkirat Singh" Cc: Subject: RE: Dummynet - Burst Loss Date: Thu, 27 Sep 2001 09:05:46 +0200 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2911.0) In-Reply-To: X-MIMEOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 Importance: Normal Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Posting back to Questions only: The only thought that occurs to me would be to write a two line script to change the config of the pipe to increase the loss percentage to 80% or 100% (whatever suits you), then return to 0% or 5% after whatever delay you are after. This could be triggered manually or even in cron if that's what you need. try something like this: ---------- #!/bin/sh # Assuming your pipe number 99 matches the packet # stream which you want test with the 'burst loss' ipfw pipe 99 config plr $2 sleep $1 ipfw pipe 99 config plr 0 ---------- If this script is called 'loss-burst' in your current directory, you could invoke it like such: # ./loss-burst 3 0.95 This would give you a 95% packet loss rate for 3 seconds. I guess you could easily add an argument to specify the ipfw pipe number too. Hope this helps. Patrick. -----Original Message----- From: owner-freebsd-questions@FreeBSD.ORG [mailto:owner-freebsd-questions@FreeBSD.ORG]On Behalf Of Harkirat Singh Sent: 27 September 2001 07:24 To: net@FreeBSD.ORG Cc: questions@FreeBSD.ORG Subject: Dummynet - Burst Loss Hello! I want to know is it possible to create a burst of packet loss using dummynet. I have used Dummynet to create a random packet loss and quiet familiar with it. However, I did not get any information as how a burst of packet loss can be created. I shall be greatfull if someone can guide me about this.. Regards, harkirat Singh To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message