From owner-freebsd-questions@FreeBSD.ORG Fri Jun 24 11:33:36 2005 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E13C116A41C for ; Fri, 24 Jun 2005 11:33:36 +0000 (GMT) (envelope-from martin@dc.cis.okstate.edu) Received: from dc.cis.okstate.edu (dc.cis.okstate.edu [139.78.100.219]) by mx1.FreeBSD.org (Postfix) with ESMTP id B6C5543D5C for ; Fri, 24 Jun 2005 11:33:36 +0000 (GMT) (envelope-from martin@dc.cis.okstate.edu) Received: from dc.cis.okstate.edu (localhost.cis.okstate.edu [127.0.0.1]) by dc.cis.okstate.edu (8.12.6/8.12.6) with ESMTP id j5OBXaT3056044 for ; Fri, 24 Jun 2005 06:33:36 -0500 (CDT) (envelope-from martin@dc.cis.okstate.edu) Message-Id: <200506241133.j5OBXaT3056044@dc.cis.okstate.edu> To: freebsd-questions@freebsd.org Date: Fri, 24 Jun 2005 06:33:36 -0500 From: Martin McCormick Subject: Re: Virtual Interfaces and Subnet Masks X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 Jun 2005 11:33:37 -0000 "Daniel Marsh" writes: >Why don't you just setup an IP alias for the fxp0 interface? > >ie: >ifconfig_fxp0_alias0="inet 192.168.1.7" Thank you. that both validates some of what I did, but raises new questions. Originally, I tried to bring up a second Ethernet card which is on the system in question and which I thought we would use if we ever had to. This had worked once before when the dead system we were replacing was on a different network and I just assumed it would work on the same network. Big mistake! After discovering the hard way about conflicting instances of the same subnetmask and getting a bit nervous because we were still down on the interface we needed most, I tried bringing up fxp1 as follows: ifconfig fxp1 192.168.1.1 This worked, but I soon realized that ifconfig gave it a default mask of 255.255.255.0 which is wrong for that network. I then tried the alias for fxp0 exactly as you indicated and got it but the packets going out still had a 255.255.255.0 mask. I ended up, somehow, with that bad mask on both the primary interface and the alias after trying to start over with ifconfig. if config -alias ifconfig fxp0 inet 192.168.1.50 netmask 255.255.252.0 ifconfig fxp0 alias 192.168.1.1 I thought of bringing fxp0 down first but was doing all of this remotely from home and was concerned that I'd loose the system completely and it would be some minutes before one of us could physically go there and take control. We or at least I don't do this very thing nearly often enough because things under FreeBSD and Linux just don't break that often and it is difficult to duplicate every possible permutation of trouble meaning that sometimes, one gets nasty surprises. While not laughing at what happened too hard, can you think of how I ended up with the bad mask that wouldn't go away? Many thanks. Martin McCormick WB5AGZ Stillwater, OK OSU Information Technology Division Network Operations Group