From owner-freebsd-stable Sat Aug 3 20:32:56 2002 Delivered-To: freebsd-stable@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id A2A4737B400 for ; Sat, 3 Aug 2002 20:32:52 -0700 (PDT) Received: from 12-222-67-235.client.insightBB.com (12-222-67-235.client.insightBB.com [12.222.67.235]) by mx1.FreeBSD.org (Postfix) with ESMTP id 139AE43E4A for ; Sat, 3 Aug 2002 20:32:52 -0700 (PDT) (envelope-from mikes@12-222-67-235.client.insightBB.com) Received: from 12-222-67-235.client.insightBB.com (localhost [127.0.0.1]) by 12-222-67-235.client.insightBB.com (8.12.5/8.12.5) with ESMTP id g743WonA089556; Sat, 3 Aug 2002 22:32:50 -0500 (EST) (envelope-from mikes@12-222-67-235.client.insightBB.com) Received: (from mikes@localhost) by 12-222-67-235.client.insightBB.com (8.12.5/8.12.5/Submit) id g743Wn5c089555; Sat, 3 Aug 2002 22:32:49 -0500 (EST) From: "Michael L. Squires" Message-Id: <200208040332.g743Wn5c089555@12-222-67-235.client.insightBB.com> Subject: Re: dhcp problems with my ISP In-Reply-To: "from Bri at Aug 3, 2002 11:12:12 am" To: Bri Date: Sat, 3 Aug 2002 22:32:49 -0500 (EST) Cc: FreeBSD Stable X-Mailer: ELM [version 2.4ME+ PL88 (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG [ Charset ISO-8859-1 unsupported, converting... ] > Hi I have a Cable and have a Cable Modem for my internet connection of which > you use dhcp to obtain an IP address great but this only seems to work > successfully on a Windows machine I've registered all the other mac > addresses of unix boxes and Apple macs I have and they seem to have alot of > difficulty obtaining IP addresses. Especially the UNIX machines which run > FreeBSD 4.5-RELEASE or 5.0-CURRENT on sparc64 at the moment the sparc64 box > which is a Sun Ultra 5 which is the worst for detecting an IP with dhclient. > > What I would really like to know is what does the windows dhcp do > differently than say dhclient. Some cable companies have started placing DHCP servers very far away from the networks they serve (more than 50 hops, in one case). This does not cause major problems with Windows since they allow 128 hops, but does cause problems with the *NIXes which use a smaller number (16?) hops. The quick fix is to recompile dhcp (/usr/src/contrib/isc-dhcp and increase the "ttl" from 16 to something bigger. The note I saw elsewhere said 128 was a reasonable figure. This occurred for a number of ATTBI BSD users elsewhere about 6/17. My memory is that this was discussed on www.dslreports.com and on some of the LINUX newsgroups. The suggested changes are to change line 155 (approx) in /usr/src/contrib/isc-dhcp/common/packet.c from ip.ip_tos = IPTOS_LOWDELAY; to ip.ip_tos = 0; and line 160 (approx) ip.ip_ttl = 16; to ip.ip_ttl = 128; This assumes, of course, that you've downloaded source for that part of the OS at least. Mike Squires To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message