From owner-freebsd-current@FreeBSD.ORG Wed Oct 10 15:04:20 2007 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 4496216A418 for ; Wed, 10 Oct 2007 15:04:20 +0000 (UTC) (envelope-from scottl@samsco.org) Received: from pooker.samsco.org (pooker.samsco.org [168.103.85.57]) by mx1.freebsd.org (Postfix) with ESMTP id D155013C458 for ; Wed, 10 Oct 2007 15:04:19 +0000 (UTC) (envelope-from scottl@samsco.org) Received: from phobos.samsco.home (phobos.samsco.home [192.168.254.11]) (authenticated bits=0) by pooker.samsco.org (8.13.8/8.13.8) with ESMTP id l9AF3rLu033925; Wed, 10 Oct 2007 09:03:54 -0600 (MDT) (envelope-from scottl@samsco.org) Message-ID: <470CE9C2.4060300@samsco.org> Date: Wed, 10 Oct 2007 09:03:30 -0600 From: Scott Long User-Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en-US; rv:1.8.1.6) Gecko/20070802 SeaMonkey/1.1.4 MIME-Version: 1.0 To: Barry Pederson References: <46A7B47F.3050300@berkeley.edu> <46A7B607.2070207@samsco.org> <20070927010139.GC22695@eschew.pusen.org> <46FF4E9B.3080104@gneto.com> <470CDF1D.5050707@barryp.org> In-Reply-To: <470CDF1D.5050707@barryp.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (pooker.samsco.org [168.103.85.57]); Wed, 10 Oct 2007 09:03:54 -0600 (MDT) X-Spam-Status: No, score=-1.4 required=5.5 tests=ALL_TRUSTED autolearn=failed version=3.1.8 X-Spam-Checker-Version: SpamAssassin 3.1.8 (2007-02-13) on pooker.samsco.org Cc: freebsd-current@freebsd.org Subject: Re: Are SATA port multipliers supported in -CURRENT? 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: Wed, 10 Oct 2007 15:04:20 -0000 Barry Pederson wrote: > Martin Nilsson wrote: >> Hi, >> >> Have you looked at the Supermicro CSE-836E1 chassis? >> http://www.supermicro.com/products/chassis/3U/836/SC836E1-R800V.cfm >> >> It is also 3U but have space for 16 drives redundant power and the >> computer! The port expander works with the LSI MegaRAID SAS8308ELP >> board and SAS/SATA drives in FreeBSD. There is also a cheaper model >> available with 16 normal SATA connectors if you prefer that. > > I've been pondering this chassis too, and have been wondering how the > FreeBSD mpt driver would react to the builtin SAS expander. I've been > using SAS3041E-R cards (cheaper than the MegaRAIDs) with drives plugged > straight into them very happily. Would that same 4-port card plugged > into a that chassis' expander simply see 16 sata drives as da0..da15? > > It looks like these chassis actually have 28-port expanders, with 4 > ports going in, 16 ports for drives, and 2 4-port groups for > daisy-chaining other chassis. Any idea if another connected chassis > full of drives would just show up as da16..da31 and so on? > There are two possible scenarios here, first is that the controller does a full topology scan and presents the drives to the OS with no OS intervention. Second is that it doesn't do a full scan, and instead presents only the drives that are directly attached. Given that the Linux driver does full discovery itself, I kind of suspect that the latter behavior is what will happen. Full SAS support is on my immediate TODO list, but it's a fairly big project. Scott