From owner-freebsd-questions Fri Aug 9 7:14:51 2002 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 3600237B400 for ; Fri, 9 Aug 2002 07:14:49 -0700 (PDT) Received: from be-well.ilk.org (lowellg.ne.client2.attbi.com [24.147.188.158]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5DE0D43E81 for ; Fri, 9 Aug 2002 07:14:48 -0700 (PDT) (envelope-from freebsd-questions-local@be-well.no-ip.com) Received: from be-well.ilk.org (lowellg.ne.client2.attbi.com [24.147.188.158]) by be-well.ilk.org (8.12.5/8.12.5) with ESMTP id g79EElmJ003171 for ; Fri, 9 Aug 2002 10:14:47 -0400 (EDT) (envelope-from freebsd-questions-local@be-well.no-ip.com) Received: (from lowell@localhost) by be-well.ilk.org (8.12.5/8.12.5/Submit) id g79EElVA003168; Fri, 9 Aug 2002 10:14:47 -0400 (EDT) X-Authentication-Warning: be-well.ilk.org: lowell set sender to freebsd-questions-local@be-well.ilk.org using -f To: freebsd-questions@freebsd.org Subject: Re: dhclient man and renew? References: <20020807200734.D33423-100000@earl-grey.cloud9.net> From: Lowell Gilbert Date: 09 Aug 2002 10:14:47 -0400 In-Reply-To: <20020807200734.D33423-100000@earl-grey.cloud9.net> Message-ID: <44ptwsunjc.fsf@be-well.ilk.org> Lines: 40 User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.2 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 Peter Leftwich writes: > Hello list, just an observation and a question about /sbin/dhclient (I > cannot determine which version of the binary I am running). > > The observation is that the manpage for `man 8 dhclient` is not a smooth > read; The flags listed at the beginning are not laid out clearly in the > following paragraphs - are there any plans for a re-write of it? It isn't > exactly clear how to use the -w and -1 flags, and I'm sure (although it may > be "contrary" to RFCs about the man command) an example wouldn't hurt. dhclient is third-party software, so changes to the manual pages are something that FreeBSD leaves to the ISC (which is the actual origin of the DHCP code). "Examples" are a standard section in BSD manual pages (ipfw(8), for a really good example). In any case, IETF RFCs are about networking protocols, not OS features, so they never have anything to say about manual pages. > My question is the following scenario. If you shut off your cable modem > (or in general, your Internet connection), say overnight, then later turn > it back on, is there a way to effectively wake up the dhclient? I would > consider the -1 or -w flags, or killing the running dhclient process or > deleting the file /var/db/dhclient.leases so that it could be obtained > again new. According to the manual page, omshell(1) should have access to some variables that will let you control the dhclient. I've always just killed the dhclient and then started it up again later, but I haven't had any need to do that later. > What actually worked this time was trying to run `arp -a` then *waiting* > patiently, maybe 2 to 3 minutes and running the command again (yeay). The 'arp -a' was probably irrelevant, except to show that things were working. Your dhclient was probably faithfully trying to renew on a periodic basis all night, and finally had some success the first time it tried after you restarted the cable modem. Aside from the short delay, this is probably fine. - Lowell To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message