From owner-freebsd-net@FreeBSD.ORG Wed Jun 29 15:43:29 2011 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9DDEC106566C for ; Wed, 29 Jun 2011 15:43:29 +0000 (UTC) (envelope-from qing.li@bluecoat.com) Received: from whisker.bluecoat.com (whisker.bluecoat.com [216.52.23.28]) by mx1.freebsd.org (Postfix) with ESMTP id 7C4018FC1D for ; Wed, 29 Jun 2011 15:43:28 +0000 (UTC) Received: from PWSVL-EXCHTS-02.internal.cacheflow.com (sai-rp.bluecoat.com [10.2.2.126] (may be forged)) by whisker.bluecoat.com (8.14.2/8.14.2) with ESMTP id p5TFSPIN004876 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=FAIL); Wed, 29 Jun 2011 08:28:26 -0700 (PDT) Received: from PWSVL-EXCMBX-01.internal.cacheflow.com ([fe80::15bc:12e2:4676:340f]) by PWSVL-EXCHTS-02.internal.cacheflow.com ([fe80::4910:317f:407:6ecc%14]) with mapi id 14.01.0255.000; Wed, 29 Jun 2011 08:28:19 -0700 From: "Li, Qing" To: Oleg Cherevko , "freebsd-net@freebsd.org" Thread-Topic: ifconfig alias: same subnet netmask question Thread-Index: AQHMNnCr+WsDCgKoG0q/gVdEqb5YnJTUdNuA Date: Wed, 29 Jun 2011 15:28:19 +0000 Message-ID: References: <4E0B406D.8070406@fb-n.l.org.ua> In-Reply-To: <4E0B406D.8070406@fb-n.l.org.ua> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.2.2.106] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Cc: Subject: RE: ifconfig alias: same subnet netmask question X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Jun 2011 15:43:29 -0000 First of all, are you encountering any issues ? There is an outstanding issue with the address alias and improper routing table update that I am actively working on. --Qing > -----Original Message----- > From: owner-freebsd-net@freebsd.org [mailto:owner-freebsd- > net@freebsd.org] On Behalf Of Oleg Cherevko > Sent: Wednesday, June 29, 2011 8:11 AM > To: freebsd-net@freebsd.org > Subject: ifconfig alias: same subnet netmask question >=20 > Hi All, >=20 > When describing the "alias" parameter ifconfig manpage claims that "If > the address is on the same subnet as the first network address for this > interface, a non-conflicting netmask must be given. Usually 0xffffffff > is most appropriate." >=20 > Taking into account that FreeBSD supports aliases from the same subnet > with identical netmask for 6+ years now, does this statement still make > sense? And what does this "conflicting netmask" stand for (I mean in > the > context of more or less recent FreeBSD versions, say 8.0+)? >=20 > Are there any drawbacks in setting aliases like this: > ifconfig em0 inet 192.168.1.1 netmask 0xffffff00 > ifconfig em0 inet 192.168.1.2 netmask 0xffffff00 > instead of traditional: > ifconfig em0 inet 192.168.1.1 netmask 0xffffff00 > ifconfig em0 inet 192.168.1.2 netmask 0xffffffff > (again, for more or less recent FreeBSD versions)? >=20 > -- > Olwi > _______________________________________________ > freebsd-net@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-net > To unsubscribe, send any mail to "freebsd-net-unsubscribe@freebsd.org"