From owner-freebsd-net Sat Sep 5 09:52:39 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id JAA12904 for freebsd-net-outgoing; Sat, 5 Sep 1998 09:52:39 -0700 (PDT) (envelope-from owner-freebsd-net@FreeBSD.ORG) Received: from fledge.watson.org (COPLAND.CODA.CS.CMU.EDU [128.2.222.48]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id JAA12892 for ; Sat, 5 Sep 1998 09:52:37 -0700 (PDT) (envelope-from robert@cyrus.watson.org) Received: from fledge.watson.org (robert@fledge.pr.watson.org [192.0.2.3]) by fledge.watson.org (8.8.8/8.8.8) with SMTP id MAA01437 for ; Sat, 5 Sep 1998 12:51:30 -0400 (EDT) Date: Sat, 5 Sep 1998 12:51:30 -0400 (EDT) From: Robert Watson X-Sender: robert@fledge.watson.org Reply-To: Robert Watson To: freebsd-net@FreeBSD.ORG Subject: netmask of 0 not permitted (3.0-current) 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 This morning I was plugged into a network, and wanted to figure out what hosts on the network were in which subnets. In particular, I knew that several hosts on the subnet believed they were on different subnets due to a configuration problem. Well, I thought, I'll just set up my ethernet device to believe that all IP addresses are local so I don't get a "no route to host" without a default router set. But then I ran into a problem: ifconfig ep0 netmask 0.0.0.0 ifconfig ep0 ep0: flags=a843 mtu 1500 inet 192.168.10.21 netmask 0xffffff00 broadcast 192.168.10.255 ether 00:a0:24:60:31:9c I can ifconfig to almost 0: ep0: flags=a843 mtu 1500 inet 192.168.10.21 netmask 0x80000000 broadcast 255.255.255.255 ether 00:a0:24:60:31:9c but not to 0 itself. It seems to me that a netmask of 0 is not illegitimate, as I might want to have all packets go to the local network. Am I doing something wrong? :) Robert N Watson Carnegie Mellon University http://www.cmu.edu/ TIS Labs at Network Associates, Inc. http://www.tis.com/ SafePort Network Services http://www.safeport.com/ robert@fledge.watson.org http://www.watson.org/~robert/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message