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From: grog@lemis.de (Greg Lehey)
Organisation: LEMIS, Schellnhausen 2, 36325 Feldatal, Germany
Phone: +49-6637-919123
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	id PAA15770; Fri, 5 Jul 1996 15:58:51 +0200
Message-Id: <199607051358.PAA15770@allegro.lemis.de>
Subject: Re: [2.1R] same IP address assigned to ed0 and ppp0 ?
To: mcw@hpato.aus.hp.com (M C Wong)
Date: Fri, 5 Jul 1996 15:58:51 +0200 (MET DST)
Cc: questions@FreeBSD.org (FreeBSD Questions)
In-Reply-To: <199607050058.AA072678307@relay.hp.com> from "M C Wong" at Jul 5, 96 10:58:23 am
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M C Wong writes:
>
> Hi,
>     Correct me if I'm wrong: FreeBSD 2.1R supports same IP addresses
> assigned onto different types of network interfaces, in particular a PPP
> interface and an Ethernet interface.

You're not wrong.  It's a good idea to conserve addresses like that.
Here's my ISDN router:

=== grog@daemon (/dev/ttyp0) /usr/home/grog 8 -> ifconfig -a
ed0: flags=8863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST> mtu 1500
        inet 192.109.197.156 netmask 0xffffff00 broadcast 192.109.197.255
lp0: flags=8810<POINTOPOINT,SIMPLEX,MULTICAST> mtu 1500
ipi0: flags=811<UP,POINTOPOINT,SIMPLEX> mtu 1500
        inet 192.109.197.156 --> 194.163.31.4 netmask 0xffffffc0 
ipi1: flags=811<UP,POINTOPOINT,SIMPLEX> mtu 1500
        inet 192.109.197.156 --> 194.64.112.1 netmask 0xffffff00 
ipi2: flags=811<UP,POINTOPOINT,SIMPLEX> mtu 1500
        inet 192.109.197.156 --> 194.163.31.129 netmask 0xffffffc0 
ipi3: flags=811<UP,POINTOPOINT,SIMPLEX> mtu 1500
        inet 192.109.197.38 --> 192.109.197.37 netmask 0xffffff00 
ipi4: flags=811<UP,POINTOPOINT,SIMPLEX> mtu 1500
        inet 192.109.197.156 --> 194.77.2.34 netmask 0xffffff00 
ipi5: flags=811<UP,POINTOPOINT,SIMPLEX> mtu 1500
        inet 192.109.197.156 --> 194.163.31.1 netmask 0xffffffc0 
ipi6: flags=811<UP,POINTOPOINT,SIMPLEX> mtu 1500
        inet 192.109.197.156 --> 192.129.52.242 netmask 0xffffff00 
ipi7: flags=810<POINTOPOINT,SIMPLEX> mtu 1500
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
        inet 127.0.0.1 netmask 0xff000000 
sl0: flags=c010<POINTOPOINT,LINK2,MULTICAST> mtu 552
tun0: flags=8010<POINTOPOINT,MULTICAST> mtu 1500

I use ipi3 for testing in the local network, that's the only reason
why it has a different interface address.

Greg