From owner-freebsd-questions@FreeBSD.ORG Tue Sep 28 13:40:10 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 96B9F16A4CE for ; Tue, 28 Sep 2004 13:40:10 +0000 (GMT) Received: from grog.secure-computing.net (grog.secure-computing.net [63.228.14.241]) by mx1.FreeBSD.org (Postfix) with ESMTP id 1F23243D48 for ; Tue, 28 Sep 2004 13:40:10 +0000 (GMT) (envelope-from ecrist@secure-computing.net) Received: from [67.1.199.77] (0-1pool199-77.nas2.fargo1.nd.us.da.qwest.net [67.1.199.77]) (authenticated bits=0)i8SDd8S4045722; Tue, 28 Sep 2004 08:39:53 -0500 (CDT) (envelope-from ecrist@secure-computing.net) In-Reply-To: References: Mime-Version: 1.0 (Apple Message framework v619) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <984880D8-1153-11D9-94B7-000D9333E43C@secure-computing.net> Content-Transfer-Encoding: 7bit From: Eric Crist Date: Tue, 28 Sep 2004 08:37:51 -0500 To: "Ted Mittelstaedt" X-Pgp-Agent: GPGMail 1.0.2 X-Mailer: Apple Mail (2.619) X-Virus-Scanned: clamd / ClamAV version 0.74, clamav-milter version 0.74a on grog.secure-computing.net X-Virus-Status: Clean cc: bsdfsse cc: russell cc: "freebsd-questions@FreeBSD.ORG" Subject: Re: IP address conflicts X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Sep 2004 13:40:10 -0000 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 For what it's worth, aside from some reconfiguration that could be a little time consuming, I would suggest putting the servers on a different subnet that everything else. If all the computers that are not servers are supposed to be configured for DHCP, insert a FreeBSD box that filters out any addresses outside that subnet. i.e. Server IP addresses are all 192.168.1.0 thru 192.168.1.50. Set your DHCP server to only assign IP addresses above 192.168.1.75 and up or so. I'm too lazy to do the math right now, but use the appropriate subnet mask and filter all the other stuff out. Aside from those students disrupting some of the other users on the network, they can't spoof the servers anymore. Just my $.02. - ----- Eric F Crist Secure Computing Networks -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (Darwin) iEYEARECAAYFAkFZaTAACgkQRAAY9knOW+qSsACghfRW0BGQg5Rq9tShVcTbcxzY C1IAn3FEjWy1BS4ROedTsC3MKIJehoOm =8XMh -----END PGP SIGNATURE-----