From owner-freebsd-net Tue May 18 21:12: 3 1999 Delivered-To: freebsd-net@freebsd.org Received: from mail-out1.apple.com (mail-out1.apple.com [17.254.0.52]) by hub.freebsd.org (Postfix) with ESMTP id 3757814E07 for ; Tue, 18 May 1999 21:12:01 -0700 (PDT) (envelope-from justin@walker3.apple.com) Received: from mailgate2.apple.com ([17.129.100.225]) by mail-out1.apple.com (8.8.5/8.8.5) with ESMTP id VAA54104 for ; Tue, 18 May 1999 21:12:01 -0700 Received: from scv3.apple.com (scv3.apple.com) by mailgate2.apple.com (mailgate2.apple.com- SMTPRS 2.0.15) with ESMTP id for ; Tue, 18 May 1999 21:11:51 -0700 Received: from walker3.apple.com (walker3.apple.com [17.219.24.201]) by scv3.apple.com (8.9.3/8.9.3) with ESMTP id VAA12514 for ; Tue, 18 May 1999 21:11:50 -0700 Received: by walker3.apple.com (8.9.1/8.9.1) id VAA00649 for freebsd-net@FreeBSD.ORG; Tue, 18 May 1999 21:11:49 -0700 (PDT) Message-Id: <199905190411.VAA00649@walker3.apple.com> To: freebsd-net@freebsd.org Subject: Re: Redirects and expire times Date: Tue, 18 May 1999 21:11:47 -0700 From: "Justin C. Walker" Reply-To: justin@apple.com X-Mailer: by Apple MailViewer (2.105.dev) Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org I don't have a lot of detailed experience with redirects, so I'm kind of flying without a net (so to speak :-}): > From: Wes Peters > Date: 1999-05-18 21:03:23 -0700 > To: Jonathan Hanna > Subject: Re: Redirects and expire times > Jonathan Hanna wrote: > > > > What is the proper way of handling ICMP redirects? I expected > > host routes to be added with an expire time, but apparently > > they are permanent. > > > > I found one old reference to this, but no reply. > > > > > Date: Mon, 11 Mar 1996 15:09:15 -0600 (CST) > > > From: Scott Mace > > > To: hackers@freebsd.org > > > Subject: Redirects and expire times... > > > Message-ID: <199603112109.PAA15480@metal.ops.neosoft.com> > > > > > > I think it is a bug to add a host route after receiving a ICMP redirect > > > and NOT having any expire set on the route. If you have a default routed > > > host in a complex topology you can get into trouble when the topology changes. > > I agree. At Xylan, we had numerous customer complaints about redirects > filling the routing table and the only way to clear them (4.2 BSD based > stack) was to reboot the switch. We added a 10-minute timeout on all > redirect routes, figuring that redirects SHOULD be the exception rather > than the rule. YMMV. We've had no customer complaints since then. ;^) Seems to me that redirects would be used for a variety of reasons: (1) bad configuration; (2) multiple subnets on a single "wire" [so a router *might* want to use redirects to avoid duplicating traffic on the wire]; and mobility. If so, none of these seem to be especially "exceptions", but more like "rules". Regards, Justin -- Justin C. Walker, Curmudgeon-At-Large * Institute for General Semantics | Manager, CoreOS Networking | Men are from Earth. Apple Computer, Inc. | Women are from Earth. 2 Infinite Loop | Deal with it. Cupertino, CA 95014 | *-------------------------------------*-------------------------------* To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message