From owner-freebsd-questions  Wed Apr  2 10:11:32 1997
Return-Path: <owner-questions>
Received: (from root@localhost)
          by freefall.freebsd.org (8.8.5/8.8.5) id KAA13655
          for questions-outgoing; Wed, 2 Apr 1997 10:11:32 -0800 (PST)
Received: from cedb.dpcsys.com (cedb.DPCSYS.com [209.25.4.3])
          by freefall.freebsd.org (8.8.5/8.8.5) with ESMTP id KAA13642
          for <questions@freebsd.org>; Wed, 2 Apr 1997 10:11:25 -0800 (PST)
Received: from localhost (dan@localhost) by cedb.dpcsys.com (8.8.5/8.8.2) with SMTP id SAA16226; Wed, 2 Apr 1997 18:10:35 GMT
Date: Wed, 2 Apr 1997 10:10:34 -0800 (PST)
From: Dan Busarow <dan@dpcsys.com>
To: Michael Ryan <mike@NetworX.ie>
cc: FreeBSD Support <questions@freebsd.org>
Subject: Re: Aliasing an IP address on 2.1R
In-Reply-To: <ECS9704021253C@NetworX.ie>
Message-ID: <Pine.UW2.3.95.970402100855.15950E-100000@cedb>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Sender: owner-questions@freebsd.org
X-Loop: FreeBSD.org
Precedence: bulk

On Wed, 2 Apr 1997, Michael Ryan wrote:
> #  ifconfig  ep0
> ep0: flags=8863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST> mtu 1500
>          inet 194.9.12.4 netmask 0xffffff00 broadcast 194.9.12.255
>          ether 00:00:c0:a3:5c:2d
> #  ifconfig  ep0  alias  10.1.0.4  netmask  255.255.255.255

The ifconfig alias only needs a netmask of 255.255.255.255 when the
real address and the alias are in the same network.

Use a netmask of 255.255.0.0 for the alias.

Dan
-- 
 Dan Busarow                                                  714 443 4172
 DPC Systems / Beach.Net                                    dan@dpcsys.com
 Dana Point, California  83 09 EF 59 E0 11 89 B4   8D 09 DB FD E1 DD 0C 82