From owner-freebsd-questions@FreeBSD.ORG Wed Jan 31 15:14:58 2007 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 4A3A616A400 for ; Wed, 31 Jan 2007 15:14:58 +0000 (UTC) (envelope-from bob.middaugh@comcast.net) Received: from rwcrmhc13.comcast.net (rwcrmhc13.comcast.net [204.127.192.83]) by mx1.freebsd.org (Postfix) with ESMTP id 394EE13C491 for ; Wed, 31 Jan 2007 15:14:58 +0000 (UTC) (envelope-from bob.middaugh@comcast.net) Received: from rmailcenter19.comcast.net ([204.127.197.129]) by comcast.net (rwcrmhc13) with SMTP id <20070131150038m1300pesege>; Wed, 31 Jan 2007 15:00:38 +0000 Received: from [199.20.117.221] by rmailcenter19.comcast.net; Wed, 31 Jan 2007 15:00:37 +0000 From: bob.middaugh@comcast.net (Bob Middaugh) To: Joe Vender , freebsd-questions@freebsd.org Date: Wed, 31 Jan 2007 15:00:37 +0000 Message-Id: <013120071500.3735.45C0AF15000B498600000E97220699849908099A0E0B0B0703D20D010D@comcast.net> X-Mailer: AT&T Message Center Version 1 (Oct 4 2006) X-Authenticated-Sender: Ym9iLm1pZGRhdWdoQGNvbWNhc3QubmV0 Cc: Subject: Re: How to stealth ports 0 and 1 on FBSD 6.2 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 31 Jan 2007 15:14:58 -0000 From: Joe Vender > I've enabled the firewall in /etc/rc.conf via: > firewall_enable="YES" > firewall_type="client" > > But, ports 0 and 1 show as CLOSED, not STEALTHED at grc.com shieldsup! scan. > I'm on a standalone desktop computer with no LAN and am using a dialup > connection to access the internet. I've set the firewall type to "client". > What changes do I need to make to the firewall configuration file in order to > stealth the ports without causing any local problems? > > Joe Vender > Hi Joe, It's been awhile since I used FreeBSD as a firewall, but I believe I had to enable the following sysctl's: As root, do: sysctl net.inet.udp.blackhole=1 do the same for: net.inet.tcp.blackhole=2 You can use either a "1" or "2" for TCP. I would use a "2". man blackhole - for more details. If they work for you , add them to /etc/sysctl.conf as just: net.inet.tcp.blackhole=2; so they'll be turned on when you reboot. Bob