From owner-freebsd-current@FreeBSD.ORG Thu Apr 21 17:48:32 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C63C5106564A; Thu, 21 Apr 2011 17:48:32 +0000 (UTC) (envelope-from lacombar@gmail.com) Received: from mail-iw0-f182.google.com (mail-iw0-f182.google.com [209.85.214.182]) by mx1.freebsd.org (Postfix) with ESMTP id 8301A8FC0A; Thu, 21 Apr 2011 17:48:32 +0000 (UTC) Received: by iwn33 with SMTP id 33so2190304iwn.13 for ; Thu, 21 Apr 2011 10:48:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:date:message-id:subject:from:to:cc :content-type:content-transfer-encoding; bh=aNAQXlalicLDb4+5ENwrKopM+gQ2Rgk6wJkOqb8r4sE=; b=vDzZ6OOylMhp+4Djr62CxsPbFiryYAvnMQJa8bxcRC3sGc5J6wSxVkqG58Lk9qTUkr +MMzcBdrOKZgr93zAI/34hV8sA0pl1Yw0PnG09/fm/TLuXKI0bBG2Jji2E7yuF+gFwoH cGbWRHZgm05kMXY8BeCIc5E5COffLGcCCWYO4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=NPExkJVplKtshv/+iozvAXJ4k8AkDKU/s6XfgVTSMJibmgAn3VAQILV3ipI94SHKWI I7LM7SOhIkenAwWYCkEDdRGGidGuUTLNgLjNlJXv3EI7Dq/eTpuJiIAAm3z7288MALHq kOCNG/FJ+m58UhqB1I+H+9ijct6cgB6soyyvM= MIME-Version: 1.0 Received: by 10.42.1.18 with SMTP id 18mr308898ice.203.1303408111595; Thu, 21 Apr 2011 10:48:31 -0700 (PDT) Received: by 10.42.177.134 with HTTP; Thu, 21 Apr 2011 10:48:31 -0700 (PDT) Date: Thu, 21 Apr 2011 13:48:31 -0400 Message-ID: From: Arnaud Lacombe To: Garrett Cooper Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: Alexander Motin , FreeBSD-Current Subject: Devices numbering [Was Re: Switch from legacy ata(4) to CAM-based ATA] X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 21 Apr 2011 17:48:32 -0000 Hi, On Thu, Apr 21, 2011 at 1:31 PM, Garrett Cooper wrote: > Although this may not be a list of fixable issues, here are some observat= ions (in part with the new geom raid infrastructure): > 1. Channels are no longer fixed of course because ata uses cam now, and I= believe that device numbering is done based on probe ordering. This is fun= to work with when dealing with appliances or configurations that require d= eterministic probe and mount, especially when drives fail, go missing, etc,= but can be hacked around in device.hints. This is why it would be nice for= geom labels to work in a sane manner. Out of context, but the same issue appear with network interfaces. If you're got 6 networks interface and the 3rd chip die, the 3 last get a bad numbering. I am not sure it is fixable by any device.hints. The Linux' world has the same issue (well, worse actually, as all interfaces uses the same 'eth' name). RedHat has been/will be introducing "Consistent Network Device Naming"[0,1] in Fedora 15, which may be an interesting move. - Arnaud [0]: http://domsch.com/linux/lpc2010/lpc2010-network-device-naming.pdf [1]: http://domsch.com/blog/?p=3D455