From owner-freebsd-questions@FreeBSD.ORG Sun Mar 10 00:45:50 2013 Return-Path: Delivered-To: questions@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id C421F1AE for ; Sun, 10 Mar 2013 00:45:50 +0000 (UTC) (envelope-from feenberg@nber.org) Received: from mail2.nber.org (mail2.nber.org [66.251.72.79]) by mx1.freebsd.org (Postfix) with ESMTP id 8513B2E0 for ; Sun, 10 Mar 2013 00:45:49 +0000 (UTC) Received: from nber7.nber.org (nber7.nber.org [66.251.72.41]) by mail2.nber.org (8.14.4/8.14.4) with ESMTP id r2A0aW7Q082908 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Sat, 9 Mar 2013 19:36:33 -0500 (EST) (envelope-from feenberg@nber.org) Date: Sat, 9 Mar 2013 19:36:32 -0500 (EST) From: Daniel Feenberg To: Modulok Subject: Re: Revoke a DHCP lease early? In-Reply-To: Message-ID: References: User-Agent: Alpine 2.02 (LRH 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; format=flowed; charset=US-ASCII X-Anti-Virus: Kaspersky Anti-Virus for Linux Mail Server 5.6.39/RELEASE, bases: 20130310 #9670857, check: 20130310 clean Cc: "questions@freebsd.org" X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 10 Mar 2013 00:45:50 -0000 On Sat, 9 Mar 2013, Modulok wrote: > List, > > I'm running isc-dhcpd to serve leases to clients. Is there a way to expire a > lease before it normally would, i.e. force a client to re-negotiate a lease > early? Perhaps some shell command akin to the following (which would be nice, > but obviously doesn't work):: > > dhcpd --revoke 192.168.1.24 I am pretty sure there is no message the dhcp server can send to a client to request it give up its IP address unless the client has asked for an address or renewal. dhcpd is a server, it doesn't initiate commands. I expect that if you modified the entry in the dhcpd.conf file and restarted dhcpd that the client would be assigned (and use) a new address the next time it tried to renew (which is typically when half the lease has been used up). My view tends to be confirmed here - http://www.cites.illinois.edu/ipam/leases.html daniel feenberg > > How do you revoke a client's lease prematurely? > > Thanks. > -Modulok- > _______________________________________________ > freebsd-questions@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org" >