From owner-freebsd-bugs Tue Oct 17 14:21:44 1995 Return-Path: owner-bugs Received: (from root@localhost) by freefall.freebsd.org (8.6.12/8.6.6) id OAA08538 for bugs-outgoing; Tue, 17 Oct 1995 14:21:44 -0700 Received: from rocky.sri.MT.net (sri.MT.net [204.94.231.129]) by freefall.freebsd.org (8.6.12/8.6.6) with ESMTP id OAA08529 for ; Tue, 17 Oct 1995 14:21:37 -0700 Received: (from nate@localhost) by rocky.sri.MT.net (8.6.12/8.6.12) id PAA08091; Tue, 17 Oct 1995 15:23:45 -0600 Date: Tue, 17 Oct 1995 15:23:45 -0600 From: Nate Williams Message-Id: <199510172123.PAA08091@rocky.sri.MT.net> To: "Garrett A. Wollman" Cc: Nate Williams , freebsd-bugs@freefall.freebsd.org Subject: Re: kern/785: 2.0.5-950622-SNAP Various ifconfig alias problems In-Reply-To: <9510172113.AA04070@halloran-eldar.lcs.mit.edu> References: <199510171950.MAA04955@freefall.freebsd.org> <199510172048.OAA07972@rocky.sri.MT.net> <9510172113.AA04070@halloran-eldar.lcs.mit.edu> Sender: owner-bugs@FreeBSD.org Precedence: bulk > > Is there anyway that ifconfig could be hacked to always use a netmask of > > 0xffffffff when alias was specified to avoid all of these kind of error > > reports? Is there *any* time when an alias is used when the netmask is > > not all 1's? > > Yes. Believe it or not, the code was not originally written to > support `fake hosts'. It was originally written to support `multiple > logical IP subnets on a single wire'. I can understand why this would be a 'good thing', but isn't this same functionality available via the alias keyword? Can you give an example of when you would use the alias keyword without an all 1's netmask? It appears from all of your responses that the netmask must always be all ones to have multiple IP addresses on a single network device. What is the limitation of using 'multiple logical IP subnets' on a single interface vs. using multiple 'fake hosts' on a single interface? Nate