From owner-freebsd-questions Sun Dec 16 16:17:13 2001 Delivered-To: freebsd-questions@freebsd.org Received: from mail1.toronto.istar.net (mail1.toronto.istar.net [209.89.75.17]) by hub.freebsd.org (Postfix) with ESMTP id E77F937B419 for ; Sun, 16 Dec 2001 16:17:02 -0800 (PST) Received: from d226-39-102.home.cgocable.net ([24.226.39.102] helo=x1-6-00-50-ba-de-36-33.kico1.on.home.com) by mail1.toronto.istar.net with esmtp (Exim 2.02 #1) id 16FlSt-0000YQ-00; Sun, 16 Dec 2001 19:17:22 -0500 Received: from localhost (genisis@localhost) by x1-6-00-50-ba-de-36-33.kico1.on.home.com (8.11.6/8.11.6) with ESMTP id fBH0O6L51471; Sun, 16 Dec 2001 19:24:44 -0500 (EST) (envelope-from genisis@istar.ca) X-Authentication-Warning: x1-6-00-50-ba-de-36-33.kico1.on.home.com: genisis owned process doing -bs Date: Sun, 16 Dec 2001 19:24:05 -0500 (EST) From: Dru X-X-Sender: To: Frederico Costa Cc: Subject: Re: Question about IPFW and ICMP:8.0 In-Reply-To: <000201c1868e$5a2affd0$0301a8c0@maxi> Message-ID: <20011216192056.O85100-100000@x1-6-00-50-ba-de-36-33.kico1.on.home.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII 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 On Mon, 17 Dec 2001, Frederico Costa wrote: > Hi all ... > > I have been using FreeBSD for almost 5 years, and lately because of the > several attempts to penetrate my system, I have set up ipfw to restrict > access from the outside to my network. > > Everything is working quiet well, but I am getting the following log > from ipfw several times: > > server /kernel: ipfw: 65435 Deny ICMP:8.0 213.142.81.223 64.4.13.33 out > via tun0 > > I have been able to understand most of the logs, but this one I just > understand that ICMP is trying to send something out to server > 64.4.13.33. but it is saying ICMP:8.0 > What that means ? > > And why should my server initiate connection without my knowledge ? > > Thanks in advance for any information... Hi Frederico, ICMP Type 8 Code 0 is an ICMP echo request, usually used by the Ping program. You might enjoy this article if you want to learn more about ICMP: http://www.onlamp.com/pub/a/bsd/2001/04/04/FreeBSD_Basics.html HTH, Dru To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message