From owner-freebsd-questions@FreeBSD.ORG Tue Apr 29 10:03:04 2003 Return-Path: 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 1EA2C37B401 for ; Tue, 29 Apr 2003 10:03:04 -0700 (PDT) Received: from sccrmhc03.attbi.com (sccrmhc03.attbi.com [204.127.202.63]) by mx1.FreeBSD.org (Postfix) with ESMTP id 822DA43F93 for ; Tue, 29 Apr 2003 10:03:03 -0700 (PDT) (envelope-from ukla@attbi.com) Received: from [192.168.1.100] (c-66-229-214-237.we.client2.attbi.com[66.229.214.237]) by sccrmhc03.attbi.com (sccrmhc03) with SMTP id <2003042917030200300flhl2e>; Tue, 29 Apr 2003 17:03:02 +0000 User-Agent: Microsoft-Entourage/9.0.2509 Date: Tue, 29 Apr 2003 10:03:02 -0700 From: Steve Warwick To: Message-ID: Mime-version: 1.0 Content-type: text/plain; charset="US-ASCII" Content-transfer-encoding: 7bit Subject: Netmasks: the truth is out there? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 29 Apr 2003 17:03:04 -0000 Hi All, I know someone out there knows the truth about netmasks. All the documentation I can find on the net talks about "masking off" part of the IP address and how you can tell network from subnet and host ids. However, I have knowledgeable friend who is telling me that the netmask is also dependant on how the hosting company has set up their routing tables and incorrect netmasking on my part can reduce or halt my connection. So the question is, who is right? Is it as simple as just masking off the first three octets or does the netmask interact with the router? Please point me to an authoritative source or if you have the time, a brief description of if or how the netmask has to match the router, as I am not sure what questions to ask my hosting company. --- My current rc.conf entry looks like this (these ips are bogus) - no broadcast and FreeBSD seems happy with this. defaultrouter="123.456.789.1" ifconfig_rl0="inet 123.456.789.111 netmask 255.255.240.0" ifconfig_rl0_alias0="inet 123.456.789.112 netmask 255.255.255.0" <+7 other aliases> Thoughts, suggestions, links ? TIA Steve