From owner-freebsd-net Tue Feb 27 21:15: 4 2001 Delivered-To: freebsd-net@freebsd.org Received: from worldclass.jolt.nu (lgh637b.hn-krukan.AC [212.217.139.112]) by hub.freebsd.org (Postfix) with ESMTP id 62A3337B71B for ; Tue, 27 Feb 2001 21:15:00 -0800 (PST) (envelope-from c4@worldclass.jolt.nu) Received: by worldclass.jolt.nu (Postfix, from userid 1000) id A069B4D; Wed, 28 Feb 2001 06:12:29 +0100 (CET) Received: from localhost (localhost [127.0.0.1]) by worldclass.jolt.nu (Postfix) with ESMTP id 75B624C; Wed, 28 Feb 2001 06:12:29 +0100 (CET) Date: Wed, 28 Feb 2001 06:12:28 +0100 (CET) From: Tobias Fredriksson To: Alex Rousskov Cc: Luigi Rizzo , freebsd-net@FreeBSD.ORG Subject: Re: Quick question about IP aliasing In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Tue, 27 Feb 2001, Alex Rousskov wrote: > On Wed, 28 Feb 2001, Luigi Rizzo wrote: > > > the source of confusion is just the fact that when you ifconfig an > > interface, you really give two distinct pieces of information: > > 1. an ip address that the machine recognises as its own > > 2. an address for a subnet connected to that interface. > > With aliases you can assign multiple instances of 1 and 2, as long > > as they are distinct. In your example the subnet address that > > you try to set with the alias is the same as the one you have > > already set with the primary ip, so the info is already there and > > you get the warning/error. > > Luigi, > > Can you be more specific please? Is it just a harmless warning > message or a true error? In other words, will anything break if I use > a.b.c.2/24 alias on the interface with the a.b.c.1/24 primary address? No you will be able to bind normaly to a.b.c.1, but i have had the problems where if i specify anything to bind a.b.c.2 and it has bound on all ip's aliased on the computer. > I hate to admit, but this thread is very confusing to me -- > several people are claiming opposite things with confidence. > Unfortunately, I cannot simply ignore the discussion. For benchmarking > purposes, we routinely use thousands of IP aliases that belong to the > same subnet on one interface without any known problems. I want to > know if we are doing something wrong. > > I do not care about the ifconfig warning by itself. We do not > even use ifconfig to manage aliases. I care about the actual run-time > code that handles the addresses. Could you please clarify whether > there is anything wrong with using, say, 10.0.0-3.1-250/16 aliases on > the same interface? > > Thanks a lot, > > Alex. > > > 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