From owner-freebsd-questions@FreeBSD.ORG Tue Nov 18 16:03:53 2014 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 57A8B7A4 for ; Tue, 18 Nov 2014 16:03:53 +0000 (UTC) Received: from mail-wg0-x231.google.com (mail-wg0-x231.google.com [IPv6:2a00:1450:400c:c00::231]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id DBE46A87 for ; Tue, 18 Nov 2014 16:03:52 +0000 (UTC) Received: by mail-wg0-f49.google.com with SMTP id x12so200518wgg.22 for ; Tue, 18 Nov 2014 08:03:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:content-type:content-transfer-encoding; bh=zchFGDGS+iVKYAaZWeP/ICP1903b3oSsRC+W0iGqHGE=; b=RYQ5hXVGVr+wpGI33pjxjL1ht8JFICIFjR6pnRZvIp91+rVTMzNaHFKZUG0qdyJtEr 77oHHMgbnwvvgdm+Mur9Mhjr2QQZQMe3Yh0P1IaMmUfIZKJSN2b07iOZoiLZU+zXPvpi Dm8us8oKwJr4vo5q1wgMYCqBaZY62oIsHXXIrRi/OR/+FGdiue3MpqvByxTwM2a2I6uj 4UOBl7w+oJFV/cGZc5/Vc0qVMQuDY8oxcTfmrs8H7YS+odp3aEUIPsM14Th3tU4F1twk Cr/yaCKd/rFBxjoSOk/RAVIUILKho5y4SXr0UPwkGe0RG/xWAKx1h5VtP53vMFkCwcPc ePSQ== X-Received: by 10.180.72.134 with SMTP id d6mr20591716wiv.73.1416326631316; Tue, 18 Nov 2014 08:03:51 -0800 (PST) Received: from t510.bsoft-company.ro (remote.ezwim.com. [193.239.202.173]) by mx.google.com with ESMTPSA id cz3sm56357611wjb.23.2014.11.18.08.03.50 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 18 Nov 2014 08:03:50 -0800 (PST) Message-ID: <546B6DE5.7040002@gmail.com> Date: Tue, 18 Nov 2014 17:03:49 +0100 From: Andrei Brezan User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: freebsd-questions@freebsd.org Subject: Re: Hardware RAID or software for ZFS References: <7F1B1DC4-46CA-4B96-836B-2D2D494F60E8@todoo.biz> In-Reply-To: <7F1B1DC4-46CA-4B96-836B-2D2D494F60E8@todoo.biz> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 Nov 2014 16:03:53 -0000 On 11/18/14 16:28, bsd@todoo.biz wrote: > Hi, > > > I would need your help in order to figure out which will be the best in order to setup a server which will be used as a Poudriere server. > > My question is related to the usage of hardware RAID controller (JBOD) or software based controller (graid) > > Server we are targeting is a SuperMicro 1018R-WC0R - 1U > > I used to build my server using an HBA such as LSI SAS 9207-8i or LSI SAS 9201-16i > Then I’ll configure the HBA as JBOD so that disks can be presented correctly to the system so that we can build our ZFS FS on top of that. > > > My sysadmin suggested me to get rid of the HBA and use direct connectivity and Graid. If your disks are SATA you can use the disks in a similar fashion as JBOD from a PCI-E controller as the onboard controller and backplane should recognize them. If they are SAS than you need a controller for them. For ZFS I don't think that anything than exposing the disk as is to ZFS gives any benefits, ZFS is designed to write directly on disk without any raid between it and the hardware layer. The caching algorithm of a raid system might tell ZFS that data was written to disk when data is still in the controller's cache for example. I've never heard of a setup with ZFS on top of gmirror or gstripe but my gut feeling is that they might not play well together as they try to address similar, if not identical, issues. > > I would like to have some feedback on various aspects : > > 1. performance > 2. usability > 3. problem one might have encountered > > > > Thanks for your feedback. > > G.B. Regards, Andrei