From owner-freebsd-questions@FreeBSD.ORG Tue Jul 8 06:06:33 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B2311106566C for ; Tue, 8 Jul 2008 06:06:33 +0000 (UTC) (envelope-from m.seaman@infracaninophile.co.uk) Received: from smtp.infracaninophile.co.uk (gate6.infracaninophile.co.uk [IPv6:2001:8b0:151:1::1]) by mx1.freebsd.org (Postfix) with ESMTP id 241FF8FC1E for ; Tue, 8 Jul 2008 06:06:32 +0000 (UTC) (envelope-from m.seaman@infracaninophile.co.uk) Received: from happy-idiot-talk.infracaninophile.co.uk (localhost [IPv6:::1]) (authenticated bits=0) by smtp.infracaninophile.co.uk (8.14.2/8.14.2) with ESMTP id m6866Lrm019510; Tue, 8 Jul 2008 07:06:28 +0100 (BST) (envelope-from m.seaman@infracaninophile.co.uk) X-DKIM: Sendmail DKIM Filter v2.6.0 smtp.infracaninophile.co.uk m6866Lrm019510 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=infracaninophile.co.uk; s=200708; t=1215497188; bh=Z1aNloqWplwIRd jUYzJFCtlszuW76/BrlSSf4aKgDbo=; h=Message-ID:Date:From:MIME-Version: To:CC:Subject:References:In-Reply-To:Content-Type:Cc:Content-Type: Date:From:In-Reply-To:Message-ID:Mime-Version:References:To; z=Mes sage-ID:=20<487303D7.1090707@infracaninophile.co.uk>|Date:=20Tue,=2 008=20Jul=202008=2007:06:15=20+0100|From:=20Matthew=20Seaman=20|Organization:=20Infracaninophile|User -Agent:=20Thunderbird=202.0.0.14=20(X11/20080607)|MIME-Version:=201 .0|To:=20Jason=20Morgan=20|CC:=20FreeBSD=20Questions=20|Subj ect:=20Re:=20Jails=20and=20IP=20Aliasing|References:=20<2daa8b4e080 7070951u607ff031v98b5b96103fdab4@mail.gmail.com>=09<20080707175440. GA95976@sentinelchicken.net>=09<2daa8b4e0807071216t7c5ef147obb794b3 f67376334@mail.gmail.com>=20<20080707193318.GB96701@sentinelchicken .net>|In-Reply-To:=20<20080707193318.GB96701@sentinelchicken.net>|X -Enigmail-Version:=200.95.6|Content-Type:=20multipart/signed=3B=20m icalg=3Dpgp-sha256=3B=0D=0A=20protocol=3D"application/pgp-signature "=3B=0D=0A=20boundary=3D"------------enigD31BD26D61CE5F637980BF2E"; b=CJbFB4U8fI/FfpR96RYtG0latcKcg5IlY5RjCp0DmACcpVWe5oBfteAEt0efNFYO7 6FiGDhwHWDvolYgmzBJTEsh+nFa7ba/o/bpkzpNuPazLMVF6oQ2QsC4+RJ8u5JLZhYo Xcf0qT1WR+52zA4m0DXnuJMhOXxGRKxnUj4zJ1c= Message-ID: <487303D7.1090707@infracaninophile.co.uk> Date: Tue, 08 Jul 2008 07:06:15 +0100 From: Matthew Seaman Organization: Infracaninophile User-Agent: Thunderbird 2.0.0.14 (X11/20080607) MIME-Version: 1.0 To: Jason Morgan References: <2daa8b4e0807070951u607ff031v98b5b96103fdab4@mail.gmail.com> <20080707175440.GA95976@sentinelchicken.net> <2daa8b4e0807071216t7c5ef147obb794b3f67376334@mail.gmail.com> <20080707193318.GB96701@sentinelchicken.net> In-Reply-To: <20080707193318.GB96701@sentinelchicken.net> X-Enigmail-Version: 0.95.6 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------enigD31BD26D61CE5F637980BF2E" X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.0 (smtp.infracaninophile.co.uk [IPv6:::1]); Tue, 08 Jul 2008 07:06:28 +0100 (BST) X-Virus-Scanned: ClamAV 0.93.1/7661/Tue Jul 8 05:08:55 2008 on happy-idiot-talk.infracaninophile.co.uk X-Virus-Status: Clean X-Spam-Status: No, score=-3.0 required=5.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VERIFIED,NO_RELAYS autolearn=ham version=3.2.5 X-Spam-Checker-Version: SpamAssassin 3.2.5 (2008-06-10) on happy-idiot-talk.infracaninophile.co.uk Cc: FreeBSD Questions Subject: Re: Jails and IP Aliasing 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: Tue, 08 Jul 2008 06:06:33 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigD31BD26D61CE5F637980BF2E Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: quoted-printable Jason Morgan wrote: > On 2008.07.07 12:16:44, David Allen wrote: >> # grep fxp0 /etc/rc.conf >> ifconfig_fxp0=3D"inet 10.0.1.2 netmask 0xffffff00" >> ifconfig_fxp0_alias0=3D"10.0.1.3 netmask 0xffffffff" >> ifconfig_fxp0_alias1=3D"10.0.1.4 netmask 0xffffffff" >> ifconfig_fxp0_alias2=3D"10.0.1.5 netmask 0xffffffff" >> >> My understanding from the handbook is that the mask should be set to a= ll >> ones if the alias is for an address that's part of the same network. = For >> a different segment, it's the first alias that should be set to the re= al >> netmask, with any additional aliases using a netmask of all ones. >> >> Granted, the broadcast addresses looks odd. If I my programming skill= s >> were better, I'd just read through the code and understand what's real= ly >> happening, but for now, I'm just taking the FreeBSD folks at their wor= d at >> following instructions. That's a roundabout way of saying I think you= r >> aliases are set up incorrectly. ;-) >=20 > That it quite possible (I do notice the newer documentation calling > for netmask 0xffffffff). But I have never had any trouble over the > last three years so, you know how it is, if it ain't (too) broke ... Using a /32 netmask for aliases in the same network as the primary address used to be mandatory until sometime during the 6.x RELEASE series. It is still recommended in the various documentation, and it does make it clear to the administrator which is the primary address when looking at ifconfig output, when that distinction is important[*]. Using the 'natural' netmask for the network the aliases are part of has worked for several years: this seems to be what most new users expect and it's familiar for users of other operating systems. As far as I know, there is no technical or performance reason to prefer one style over the other -- just a matter of administrator preference. Cheers, Matthew [*] ie. which is the source address used for connection /from/ the server. If all the aliases are used for jails, or all your software is configured to bind to one or other of the addresses this doesn't come into play. --=20 Dr Matthew J Seaman MA, D.Phil. 7 Priory Courtyard Flat 3 PGP: http://www.infracaninophile.co.uk/pgpkey Ramsgate Kent, CT11 9PW --------------enigD31BD26D61CE5F637980BF2E Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (FreeBSD) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEAREIAAYFAkhzA90ACgkQ8Mjk52CukIy4wQCZARi3cPIBkv9pRLfGNMNXdDvX x2IAniah2dqtfNUdQF5EZIG4t10z/ODR =ixlu -----END PGP SIGNATURE----- --------------enigD31BD26D61CE5F637980BF2E--