From owner-freebsd-net Tue Aug 28 8:19: 5 2001 Delivered-To: freebsd-net@freebsd.org Received: from mercury.ccmr.cornell.edu (mercury.ccmr.cornell.edu [128.84.231.97]) by hub.freebsd.org (Postfix) with ESMTP id 14F4D37B401; Tue, 28 Aug 2001 08:18:59 -0700 (PDT) (envelope-from mitch@ccmr.cornell.edu) Received: from ruby.ccmr.cornell.edu (IDENT:0@ruby.ccmr.cornell.edu [128.84.231.115]) by mercury.ccmr.cornell.edu (8.9.3/8.9.3) with ESMTP id LAA26219; Tue, 28 Aug 2001 11:19:03 -0400 Received: from localhost (mitch@localhost) by ruby.ccmr.cornell.edu (8.9.3/8.9.3) with ESMTP id LAA01465; Tue, 28 Aug 2001 11:18:58 -0400 X-Authentication-Warning: ruby.ccmr.cornell.edu: mitch owned process doing -bs Date: Tue, 28 Aug 2001 11:18:58 -0400 (EDT) From: Mitch Collinsworth To: Ruslan Ermilov Cc: Joshua Goodall , freebsd-net@FreeBSD.ORG Subject: Re: Gratuitous ARP In-Reply-To: <20010828180859.B39758@sunbay.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org It's not clear what Jushua is asking for, but my guess is proxy arp. See arp(8), in particular the -s flag. -Mitch On Tue, 28 Aug 2001, Ruslan Ermilov wrote: > On Tue, Aug 28, 2001 at 01:47:20PM +0100, Joshua Goodall wrote: > > > > Easy question time, but I can't find it documented. How can I reliably > > (and non-destructively) trigger the sending of a single gratuitous ARP > > reply for some local IP/MAC address? > > > Under "local", do you mean the IP assigned to one of the local host's > interfaces? If so, that could be done with ifconfig(8), though a bit > tricky. > > For example, let assume that 192.168.0.1 is the address assigned to the > if0 interface with the standard Class C netmask of 255.255.255.0. Then, > if you run `ifconfig if0 192.168.0.1', that will cause the gratuitous > ARP to be sent out, but that will delete and re-add the 192.168.0.1 > address to the if0 interface blowing up any routes that used this > address, probably the `default' route. > > The magic here is to use the `netmask' and `alias' keywords. That is, > `ifconfig if0 192.168.0.1 netmask 255.255.255.0 alias' will achieve the > desired effect. You can omit the address part (192.168.0.1) and the > `alias' keyword, if the 192.168.0.1 is the only address bound to the > if0 interface, like this: `ifconfig if0 netmask 255.255.255.0'. > > > Cheers, > -- > Ruslan Ermilov Oracle Developer/DBA, > ru@sunbay.com Sunbay Software AG, > ru@FreeBSD.org FreeBSD committer, > +380.652.512.251 Simferopol, Ukraine > > http://www.FreeBSD.org The Power To Serve > http://www.oracle.com Enabling The Information Age > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-net" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message