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	<title>The Storage Architect &#187; Drobo</title>
	<atom:link href="http://thestoragearchitect.com/tag/drobo/feed/" rel="self" type="application/rss+xml" />
	<link>http://thestoragearchitect.com</link>
	<description>Storage, Virtualisation &#38; Cloud</description>
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		<title>Drive Prices Increase &#8211; Who Will Suffer Most?</title>
		<link>http://thestoragearchitect.com/2011/11/06/drive-prices-increase-who-will-suffer-most/</link>
		<comments>http://thestoragearchitect.com/2011/11/06/drive-prices-increase-who-will-suffer-most/#comments</comments>
		<pubDate>Sun, 06 Nov 2011 21:24:21 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Storage]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[EMC]]></category>
		<category><![CDATA[hard drives]]></category>
		<category><![CDATA[HDD]]></category>
		<category><![CDATA[Netapp]]></category>
		<category><![CDATA[storagezilla]]></category>
		<category><![CDATA[Thailand]]></category>
		<category><![CDATA[TouchDown PR]]></category>
		<category><![CDATA[Western Digital]]></category>

		<guid isPermaLink="false">http://thestoragearchitect.com/?p=3062</guid>
		<description><![CDATA[<p>Storagezilla calls out hard disk availability in his <a rel="nofollow" href="http://storagezilla.typepad.com/storagezilla/2011/11/drought.html" target="_blank">recent post</a>.  In fact, I discussed the subject of drive prices last week with James Carter of <a href="http://www.touchdownpr.com/" target="_blank">Touchdown PR</a> on my way to SNW Europe.  James highlighted he was seeing prices on standard drives having doubled recently.</p> <p>I went back and looked [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>Storagezilla calls out hard disk availability in his <a rel="nofollow" href="http://storagezilla.typepad.com/storagezilla/2011/11/drought.html"  target="_blank">recent post</a>.  In fact, I discussed the subject of drive prices last week with James Carter of <a href="http://www.touchdownpr.com/"  target="_blank">Touchdown PR</a> on my way to SNW Europe.  James highlighted he was seeing prices on standard drives having doubled recently.</p>
<p>I went back and looked at my last drive purchases &#8211; two Western Digital 2TB SATA-II drives at around £65 each.  Currently these are now retailing on Amazon for £150 each, with the latest 2TB drives around the £100 mark.</p>
<p>Prices have clearly risen sharply due to the flooding in Thailand, however I wonder, which vendor suffers the most in this scenario?</p>
<p>The most obvious answer would appear to be that the vendors with the least margin will suffer most.  Think of the likes of Drobo or Overland, who sell relatively low cost hardware.  Theoretically vendors such as EMC and Netapp should be able to swallow the additional cost, especially if they are already charging 10-15 times the underlying raw cost of the drive on a per terabyte basis.  The drive cost makes up a small part of their overall price.  The big vendors should also have the muscle to fulfill their demand first with what supply is available.</p>
<p>However I don&#8217;t think things are that simple.  Drobo arrays can be purchased without disk drives, allowing them to use whatever drives are available, so drive prices won&#8217;t hurt bare array sales.  These arrays also allow mix and match and to upgrade per drive, so are potentially more flexible.</p>
<p>Bear in mind savvy customers of EMC and others will have negotiated quarterly price erosion, so those on existing deals will probably not see much change.  I would expect the big boys to have hedged their supplies through multiple supply lines and stockpiles but their margins will be affected if supply problems persist.</p>
<p>It&#8217;s also worth thinking about efficiency at this point.  If you&#8217;re not using thin provisioning or other data reduction technologies, then you should be.  If your vendor doesn&#8217;t offer it, then there are plenty out there who do.  As prices rise, it may be time to look again at implementing these features and fixing the processes that stop you using them today.</p>
<p>One last thought.  Are NAND prices being affected?  If not then the SSD array manufacturers must be rubbing their hands together with glee.</p>
<p>&nbsp;</p>
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		<item>
		<title>Data Robotics Releases Business-class Arrays</title>
		<link>http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/</link>
		<comments>http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/#comments</comments>
		<pubDate>Tue, 08 Feb 2011 08:24:53 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Featured]]></category>
		<category><![CDATA[Storage]]></category>
		<category><![CDATA[B1200i]]></category>
		<category><![CDATA[B800fs]]></category>
		<category><![CDATA[B800i]]></category>
		<category><![CDATA[Data Robotics]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[EMC]]></category>
		<category><![CDATA[HP]]></category>
		<category><![CDATA[ibm]]></category>
		<category><![CDATA[P2000]]></category>
		<category><![CDATA[SAS]]></category>
		<category><![CDATA[ssd]]></category>
		<category><![CDATA[Storwize]]></category>
		<category><![CDATA[thin provisioning]]></category>
		<category><![CDATA[tiering]]></category>
		<category><![CDATA[V7000]]></category>
		<category><![CDATA[VNXe]]></category>

		<guid isPermaLink="false">http://www.thestoragearchitect.com/?p=2346</guid>
		<description><![CDATA[<p>Today Data Robotics (<a href="http://www.drobo.com/" target="_blank">Drobo</a>) are <a href="http://www.drobo.com/news/pr/press_release_2011_02_8a.php" target="_blank">announcing</a> a new range of storage devices specifically targeted at business customers.  However this is a market that already has many players; what are they offering and how will they fare in this already competitive market?</p> New Devices <p>First of all, let&#8217;s take a look at [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>Today Data Robotics (<a href="http://www.drobo.com/"  target="_blank">Drobo</a>) are <a href="http://www.drobo.com/news/pr/press_release_2011_02_8a.php"  target="_blank">announcing</a> a new range of storage devices specifically targeted at business customers.  However this is a market that already has many players; what are they offering and how will they fare in this already competitive market?</p>
<h3>New Devices</h3>
<p>First of all, let&#8217;s take a look at the new storage devices.  Nomenclature has been changed over previous models (business people like nice code names) and so we have the following new devices:</p>
<ul>
<li>B800fs &#8211; 8-bay NAS model</li>
<li>B800i &#8211; 8-bay iSCSI SAN model</li>
<li>B1200i &#8211; 12-bay iSCSI SAN model</li>
</ul>
<p>It&#8217;s a pretty easy guess that the codes mean <em><strong>&#8220;B&#8221;</strong></em> for business, <em><strong>&#8220;fs&#8221;</strong></em> for file sharing <strong><em>&#8220;i&#8221; </em></strong>for iSCSI and the numbers designate the drive count in the chassis.  What&#8217;s new here from a hardware perspective is the 12-drive model, specifically designed as a rack-mount device.  Now business-class storage devices are very different from those used in an office environment by (for example) media developers or for local backup.  Consequently Drobo have had to step up to the mark and improve the resiliency of the existing hardware.  Therefore the new B1200i support all hot-swappable components (except the passive backplane) and additional power supplies and Ethernet connections have been added.  Note that the B800 models have not been upgraded in this way and still have a single power supply and dual Ethernet connections.  Images of the new devices are shown in this post.  It&#8217;s interesting to see that the B1200i rear view shows four expansion slots for connectivity, of which only two appear to be used.  Presumably the other two are for future expansion.</p>
<h3>Software and Features</h3>
<p>As mentioned earlier, the small device business market is a competitive place; EMC have just released their VNXe product, HP have the P2000 array; IBM recently released the StorWize v7000.  These storage appliances are fully specified devices offering advanced features for a low cost.  The features and software component could be an issue for Drobo.  The new models offer the excellent BeyondRAID functionality and only an additional tiering  option.</p>
<ul>
<li>BeyondRAID is Drobo&#8217;s thin provisioning and RAID technology combined.  In essence, data is laid out across the disks using RAID at the block level rather than replicating whole disks.  This methodology enables dis-similar disk capacities to be used in the device and for disks to be replaced or upgraded over time in order to increase capacity.  BeyondRAID provides the customers many advantages; disks can be purchased and added to the system as required, even though a greater logical capacity of storage has been configured.  This logical capacity doesn&#8217;t need to be changed as physical capacity increases.  Drives of greater capacity can be added over time, so customers can purchase the most effective price/capacity drive for their needs.  Also a single drive can be replaced without rebuilding the entire RAID set, only copying data that was on any removed drive.</li>
<li>Data-aware Tiering.  The new Drobo model now support automated tiering of data across different device types, including SATA, SAS and SSD disks.  Tiering uses fixed algorithms to determine the best placement for data based on usage.  My first thoughts were that a fixed tiering algorithm might not be appropriate, however taking a step back and looking at the market this device is targeted for, many customers taking their first steps into SAN technology may not want or need to understand how things work under the covers.</li>
</ul>
<p>However good the hardware is, ease of management is all about the software.  As a result, Drobo have released a new version of their dashboard, screenshots of which can be seen in the attached images.  Better management software for Drobo was always a requirement.  The existing dashboard doesn&#8217;t scale easily with multiple devices and there are a few major flaws within the software that would reduce the appeal to business.  It appears that the scalability issues have been addressed, but only a test-drive will tell how much better the software really is.</p>
<h3>Summary</h3>
<p>The entry-level SAN array market is becoming increasingly competitive.  There are many companies targeting this space, not including the big storage names I&#8217;ve mentioned earlier.  Data Robotics are pitching the new business models from £1409 ($2000) upwards, which presumably is for the B800i rather than the 12-bay model.  Although this does exclude disks, the price does seem competitive, as drives can be purchased by the customer at the lowest cost and added as required.  The competition will cite lack of features, but these are easily added with software releases and will be key to the success of the new devices.  In addition, the management software needs to be business-class or will be a major stumbling block.  Here are just a few features of the existing software that need to be improved:</p>
<ul>
<li><strong>Pre-emptive hot-swap </strong>- currently a drive replacement is a recovery operation.  When a drive is removed, the Drobo rebuilds RAID from the remaining disks.  It would be better to allow this replacement process to happen pre-emptively, copying data off to a new disk (if slots are available) before the a disk is removed.  This also reduces the impact on performance as RAID rebuilds need to happen as quickly as possible, whereas planned data migrations can be run as background tasks.</li>
<li><strong>iSCSI Management </strong>- the existing iSCSI interface isn&#8217;t fully featured.  The dashboard only indicates when a single host has logged into an iSCSI target/LUN but doesn&#8217;t indicate the server name or IP address.  This can be frustrating in large environments where, for instance, an over-zealous VMware host acquires all LUNs on a device.  Sharing of LUNs is also not permitted today.</li>
<li><strong>Capacity Management </strong>- although the Drobo understands thin provisioning, it only reports utilised capacity for devices that have a recognised file system and are connected to a host running the Drobo dashboard.  However the device itself must know how much data is being used by each LUN, irrespective of the file format.  That data needs to be presented to the user, otherwise real capacity planning can&#8217;t be done.</li>
</ul>
<p>Overall, I think Drobo are making an exciting move into the business space.  Price sensitivity is an issue in this market and the initial costs are low enough to be attractive to many new customers.  Data Robotics also offer a maintenance contract (DroboCare) for replacement parts, another key business feature.  Key success factors will be the improvement management interface and addition of new features to the device over time.  With 150,000 devices sold to date, Drobo appears to be a force to be reckoned with for the future.
<a href='http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/drobologo/' title='DroboLogo'><img width="150" height="84" src="http://thestoragearchitect.com/wp-content/uploads/2011/02/DroboLogo.png" class="attachment-thumbnail" alt="DroboLogo" title="DroboLogo" /></a>
<a href='http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/drobo-b1200i-back-jpg/' title='Drobo B1200i '><img width="150" height="81" src="http://thestoragearchitect.com/wp-content/uploads/2011/02/Drobo-B1200i-BACK.jpg.jpeg" class="attachment-thumbnail" alt="Drobo B1200i" title="Drobo B1200i" /></a>
<a href='http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/drobo-b1200i-rt-hero-jpg/' title='Drobo B1200i '><img width="150" height="81" src="http://thestoragearchitect.com/wp-content/uploads/2011/02/Drobo-B1200i-RT-HERO.jpg.jpeg" class="attachment-thumbnail" alt="Drobo B1200i" title="Drobo B1200i" /></a>
<a href='http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/drobo-b800i-back_mid-size/' title='Drobo B800i'><img width="150" height="81" src="http://thestoragearchitect.com/wp-content/uploads/2011/02/Drobo-B800i-Back_mid-size.jpg" class="attachment-thumbnail" alt="Drobo B800i" title="Drobo B800i" /></a>
<a href='http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/drobo-b800fs-back_mid-seize/' title='Drobo B800fs '><img width="150" height="81" src="http://thestoragearchitect.com/wp-content/uploads/2011/02/Drobo-B800fs-Back_mid-seize.jpg" class="attachment-thumbnail" alt="Drobo B800fs" title="Drobo B800fs" /></a>
<a href='http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/screen-shot-2011-01-31-at-4-00-19-pm/' title='Drobo Dashboard'><img width="150" height="107" src="http://thestoragearchitect.com/wp-content/uploads/2011/02/Screen-shot-2011-01-31-at-4.00.19-PM.png" class="attachment-thumbnail" alt="Drobo Dashboard" title="Drobo Dashboard" /></a>
<a href='http://thestoragearchitect.com/2011/02/08/data-robotics-releases-business-class-arrays/screen-shot-2011-02-01-at-5-43-13-pm/' title='Drobo Dashboard'><img width="150" height="107" src="http://thestoragearchitect.com/wp-content/uploads/2011/02/Screen-shot-2011-02-01-at-5.43.13-PM.png" class="attachment-thumbnail" alt="Drobo Dashboard" title="Drobo Dashboard" /></a>
 </p>
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		<item>
		<title>How Many Drives? 47</title>
		<link>http://thestoragearchitect.com/2011/01/24/how-many-drives-47/</link>
		<comments>http://thestoragearchitect.com/2011/01/24/how-many-drives-47/#comments</comments>
		<pubDate>Mon, 24 Jan 2011 10:18:08 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Storage]]></category>
		<category><![CDATA[Clariion]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[ix5]]></category>
		<category><![CDATA[NS4600]]></category>

		<guid isPermaLink="false">http://www.thestoragearchitect.com/?p=2159</guid>
		<description><![CDATA[<p>Rick Vanover asked the question; &#8220;how many hard drives are spinning in your home lab/home today?&#8221;.</p> <p>My answer was 47, which quite surprised me.  It&#8217;s comprised of:</p> Drobo Devices; 5 + 4 + 3 = 12 iX4 Devices; 4 + 4 = 8 NS4600 Device; 3 Backup HDD (SafePro); 1 CLARiiON; 15 Home Lab PCs; [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>Rick Vanover asked the question; &#8220;how many hard drives are spinning in your home lab/home today?&#8221;.</p>
<p>My answer was 47, which quite surprised me.  It&#8217;s comprised of:</p>
<ul>
<li>Drobo Devices; 5 + 4 + 3 = 12</li>
<li>iX4 Devices; 4 + 4 = 8</li>
<li>NS4600 Device; 3</li>
<li>Backup HDD (SafePro); 1</li>
<li>CLARiiON; 15</li>
<li>Home Lab PCs; 2 + 2 + 3</li>
<li>Desktop Mac; 1</li>
</ul>
<p>That totals 47.  This didn&#8217;t include other home devices that weren&#8217;t powered up at the time.</p>
<p>Probably a more interesting question would be to ask how much useful data is on those devices; I suspect I have a lot of duplication; copies of the same O/S, backups of backups of data and duplicates of data I&#8217;ve not noticed.  With a glut of capacity, even in a home environment, it&#8217;s easy to become lazy when keeping data in order.  While it may seem pointless to waste time keeping data ordered, when a device fails, the critical issue becomes one of determining where the most current copy of information is stored.</p>
<p>If you&#8217;ve committed to using a home storage device, ask yourself the following;</p>
<ul>
<li>What happens if the storage device fails?</li>
<li>What happens if one of the HDDs in the device fails?</li>
<li>What happens if someone steals the device (home breakin)?</li>
<li>What happens if I have fire at home?</li>
<li>How long would it take me to copy my data to another device/location?</li>
</ul>
<p>We&#8217;re becoming more dependent on home storage and the impact of failure of these devices will become more of a problem.  I&#8217;m sure there are many people who have lost precious photographs or video as most of this data is now digital.</p>
<p>Take some time and think about the value you have in your home storage device and I&#8217;m sure most people will see the value of spending a few more pounds and investing in an extra drive for backup.</p>
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		<item>
		<title>Choosing Between Monolithic and Modular Architectures &#8211; Part I</title>
		<link>http://thestoragearchitect.com/2010/08/24/choosing-between-monolithic-and-modular-architectures-part-i/</link>
		<comments>http://thestoragearchitect.com/2010/08/24/choosing-between-monolithic-and-modular-architectures-part-i/#comments</comments>
		<pubDate>Tue, 24 Aug 2010 18:19:32 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Featured]]></category>
		<category><![CDATA[Storage]]></category>
		<category><![CDATA[Ulitzer]]></category>
		<category><![CDATA[AMS]]></category>
		<category><![CDATA[Clariion]]></category>
		<category><![CDATA[DMX]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[EMC]]></category>
		<category><![CDATA[EVA]]></category>
		<category><![CDATA[HDS]]></category>
		<category><![CDATA[hitachi]]></category>
		<category><![CDATA[Netapp]]></category>
		<category><![CDATA[usp]]></category>
		<category><![CDATA[USP-V]]></category>

		<guid isPermaLink="false">http://www.thestoragearchitect.com/?p=1802</guid>
		<description><![CDATA[<p>The recent proposed <a href="http://www.thestoragearchitect.com/2010/08/23/hp-challenges-dell-for-3par/" target="_blank">acquisition</a> of 3Par by Dell and/or HP has made me think a little more about the direction the storage industry is taking in terms of their storage array design architecture.  Since storage arrays became a category of devices in their own right, we&#8217;ve seen the growth of the monolithic, sometimes [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>The recent proposed <a href="http://www.thestoragearchitect.com/2010/08/23/hp-challenges-dell-for-3par/"  target="_blank">acquisition</a> of 3Par by Dell and/or HP has made me think a little more about the direction the storage industry is taking in terms of their storage array design architecture.  Since storage arrays became a category of devices in their own right, we&#8217;ve seen the growth of the monolithic, sometimes called Enterprise storage array.  Hu Yoshida discusses the subject on one of his <a href="http://blogs.hds.com/hu/2010/08/monolithic-versus-modular-storage-is-not-an-eitheror-question.html"  target="_blank">recent blog posts</a>.  Looking at the wide range of storage devices, I&#8217;ve categorised arrays into the following groups:</p>
<ul>
<li><strong>Monolithic </strong> &#8211; this architecture is characterised by Hitachi USP, HP XP &amp; EMC DMX and consists of a shared memory architecture and multiple redundant components.</li>
<li><strong>Multi-Node</strong> &#8211; these devices use loosely coupled storage &#8220;nodes&#8221; with a high-speed interconnect providing scalability by adding extra nodes to the storage &#8220;cluster&#8221;.  Products in this category include EMC VMAX and 3Par InServ.</li>
<li><strong>Closely Coupled Dual Controller</strong> &#8211; this is the typical &#8220;modular&#8221; storage architecture characterised by IBM DS8000, EMC CLARiiON, Hitachi AMS and HP EVA.</li>
<li><strong>Loosely Coupled Dual Controller </strong>- this category describes technology that are capable of device failover but aren&#8217;t closely coupled to enable individual LUN failover as the Closely Coupled model permits.  This category is characterised by arrays such as Netapp FAS filers and Compellent Storage Center.</li>
<li><strong>Single Controller</strong> &#8211; this category covers devices that act as standalone products, including SOHO storage devices such as the Iomega IX4 &amp; Data Robotics Drobo series.</li>
</ul>
<p>The above list isn&#8217;t exhaustive and it&#8217;s my own personal categorisation.  There are many more vendors of technology than I&#8217;ve listed here.  In addition, none of these lists qualify as &#8220;Enterprise&#8221; in their own right.  The use of this term is a hotly debated subject.</p>
<h3>Monolithic Architectures</h3>
<div id="attachment_1831" class="wp-caption alignleft" style="width: 310px"><a href="http://31.222.189.99/wp-content/uploads/2010/08/DMX-Architecture.jpg" ><img class="size-medium wp-image-1831" style="margin: 5px; border: 1px solid black;" title="DMX Architecture" src="http://50.57.85.110/wp-content/uploads/2010/08/DMX-Architecture-300x213.jpg" alt="DMX Architecture" width="300" height="213" /></a><p class="wp-caption-text">EMC DMX High Level Architecture</p></div>
<p>Monolithic arrays use a shared cache architecture to connect front-end storage ports to back-end disk.  This is shown clearly in the architecture diagrams shown here, representing the internal connectivity of the EMC DMX  and Hitachi USP storage arrays.  Each of the memory units is connected to each of the front-end directors and the back-end disk directors.  Hitachi divide their cache into two halves for Clusters 1 &amp; 2 in the array; EMC have up to eight cache modules.  This architecture has positive and negative benefits; firstly having director connections connecting to all cache modules ensures resources aren&#8217;t fragmented;  unless cache becomes completely exhausted there&#8217;s always connectivity to another cache module to process a user request.  It also doesn&#8217;t matter on which port that request comes in; the cache module can process any request from any port to any back-end disk.  This connectivity is also beneficial in terms of failure.  If a cache module fails, for example, only the cache on that module is lost; in a fully deployed architecture the total cache would drop (by 1/8th in EMC&#8217;s case), but front and back-end connectivity would remain the same.  With this model it is possible pair up storage ports and have a single LUN presented from 1 or more ports with no performance impact; the path length between a storage port and disk adaptor will always be the same.</p>
<p>This any-to-any model also has disadvantages.  The connectivity is complex and therefore becomes expensive and requires overhead to manage and control the interaction between the various components.  In addition, there&#8217;s a limit to the practical scalability of this architecture.  With eight FE, BE and cache modules, there are 128 connections in place; (8x8x2).  Adding a single cache module requires an additional 16 connections; similarly, adding more front or back-end directors requires more connectivity.  Also monolithic arrays are based on custom components and custom design, increasing the ongoing maintenance and development costs for the hardware.</p>
<p>One other point to remember; front and back-end directors have their own processors.  It is possible for the traffic across the directors to be unbalanced and for some processors to be more heavily utilised than others.  I&#8217;ve seen a number of configurations where USP V FED ports are running at 100% processor utilisation due to to small block sizes.  This means manual load balancing is required both in initial host placement and subsequently as traffic load increases.  This fact is worth bearing in mind as we move to more highly virtualised environments as it is likely host port utilisation will start low and rise over time as more virtual machines are created.</p>
<div id="attachment_1832" class="wp-caption alignleft" style="width: 310px"><a href="http://31.222.189.99/wp-content/uploads/2010/08/Hitachi-Architecture.jpg" ><img class="size-medium wp-image-1832" style="border: 1px solid black; margin: 5px;" title="Hitachi Architecture" src="http://50.57.85.110/wp-content/uploads/2010/08/Hitachi-Architecture-300x212.jpg" alt="Hitachi Architecture" width="300" height="212" /></a><p class="wp-caption-text">Hitachi USP High Level Architecture</p></div>
<p>Now that the DMX platform has been put out to pasture in place of VMAX, it appears Hitachi are the only vendor continuing down the monolithic route.  Next time I&#8217;ll discuss Multi-Node arrays and why they may (or may not) be a replacement for today&#8217;s monolithic devices.</p>
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		<title>Hardware Review: Drobo Elite &#8211; Part I</title>
		<link>http://thestoragearchitect.com/2010/06/02/hardware-review-drobo-elite-part-i/</link>
		<comments>http://thestoragearchitect.com/2010/06/02/hardware-review-drobo-elite-part-i/#comments</comments>
		<pubDate>Wed, 02 Jun 2010 07:00:59 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Featured]]></category>
		<category><![CDATA[Reviews]]></category>
		<category><![CDATA[Data Robotics]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[DroboElite]]></category>
		<category><![CDATA[DroboPro]]></category>
		<category><![CDATA[ESATA]]></category>
		<category><![CDATA[iSCSI]]></category>
		<category><![CDATA[Rack Mount Storage]]></category>
		<category><![CDATA[SMB Storage]]></category>
		<category><![CDATA[USB]]></category>

		<guid isPermaLink="false">http://www.thestoragearchitect.com/?p=1384</guid>
		<description><![CDATA[<p>This post is the first in a series covering the <a href="http://www.datarobotics.com/products/droboelite.php" title="Drobo Elite" target="_blank">DroboElite</a> SMB storage device from <a href="http://www.datarobotics.com/" title="www.datarobotics.com" target="_blank">Data Robotics Inc</a>.</p> <p>The DroboElite is the most fully featured storage array in the Data Robotics range of devices.  Regular readers will know I&#8217;ve posted frequently on these devices, from the first <a href="http://www.datarobotics.com/products/drobo.php" title="Drobo Classic" [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<div id="attachment_1509" class="wp-caption alignleft" style="width: 310px"><a href="http://31.222.189.99/wp-content/uploads/2010/05/DroboElite_Back_Low.jpg" ><img class="size-medium wp-image-1509" title="Drobo Elite - Rear View" src="http://50.57.85.110/wp-content/uploads/2010/05/DroboElite_Back_Low-300x128.jpg" alt="Drobo Elite - Rear View" width="300" height="128" /></a><p class="wp-caption-text">Drobo Elite - Rear View</p></div>
<p>This post is the first in a series covering the <a href="http://www.datarobotics.com/products/droboelite.php" title="Drobo Elite"  target="_blank">DroboElite</a> SMB storage device from <a href="http://www.datarobotics.com/" title="www.datarobotics.com"  target="_blank">Data Robotics Inc</a>.</p>
<p>The DroboElite is the most fully featured storage array in the Data Robotics range of devices.  Regular readers will know I&#8217;ve posted frequently on these devices, from the first <a href="http://www.datarobotics.com/products/drobo.php" title="Drobo Classic"  target="_blank">Drobo</a> &#8220;Classic&#8221; to the <a href="http://www.datarobotics.com/products/drobopro/index.php" title="DroboPro"  target="_blank">DroboPro</a>, both of which I own and have purchased myself.  Data Robotics have kindly loaned me a DroboElite for this series of posts.  As you will see, the top of the range model offers all the features the other models provide, plus the benefits of multi-user support.</p>
<h3>Background</h3>
<p>The original Data Robotics storage device was what is now referred to as the Drobo &#8220;Classic&#8221;.  This was a 4-bay storage device, connecting to a single host PC/server using USB or Firewire and later eSATA.  This model evolved into the Drobo S and was complemented with the 8-bay DroboPro.  Finally, the DroboElite was <a href="http://www.datarobotics.com/news/pr/press_release_2009_11_23a.php" title="Data Robotics Press Release"  target="_blank">released</a> in November 2009, using the same form factor as the &#8216;Pro but with additional connectivity and features.  Although the &#8216;Pro and &#8216;Elite models shared the same look and feel, they are actually different products and so there&#8217;s no upgrade process to remove drives from the &#8216;Pro and install into an &#8216;Elite shell.</p>
<h3>Physical</h3>
<p>The DroboElite is an 8-bay device, accommodating standard 3.5&#8243; SATA form factor drives.  The drives are inserted vertically (rather than horizontally in the 4-bay models), with drive&#8217;s top side pointing to the right.  No caddy or additional support is required.  From the front, there&#8217;s nothing to separate the &#8216;Pro and the &#8216;Elite as they look identical.  In fact, the removable magnetic front bezel only says &#8220;Drobo&#8221; and has no other distinguishing markings.  One thought worth considering for the future is providing a method of identifying multiple Drobo&#8217;s that have been installed into a rack or cabinet.  The drive lights can be flashed on and off but this only lasts for a few seconds and wouldn&#8217;t help an engineer who&#8217;s alone in a data centre or machine room.  This is a particularly important point as the &#8216;Elite is a multi-user device and so aimed at SMBs with machine rooms and rack-based equipment (a rack mount  kit is available).</p>
<div id="attachment_1510" class="wp-caption alignleft" style="width: 310px"><a href="http://31.222.189.99/wp-content/uploads/2010/05/droboelite-open-lo.jpg" ><img class="size-medium wp-image-1510" title="Drobo Elite (Bezel Removed)" src="http://50.57.85.110/wp-content/uploads/2010/05/droboelite-open-lo-300x128.jpg" alt="Drobo Elite (Bezel Removed)" width="300" height="128" /></a><p class="wp-caption-text">Drobo Elite (Bezel Removed)</p></div>
<p>Turning to the back of the &#8216;Elite, we start to see the differences with previous models.  The major one here is the presence of two Ethernet ports, providing network redundancy and multi-pathing support for iSCSI.  The power supply is still built in (and not removable), plus there&#8217;s a power switch and a USB connector &#8211; that it.  I&#8217;m undecided as to whether an integrated PSU is a good or a bad thing and I flip back and forth between internal/external and multiple supplies each time I think about it.  On reflection, the consideration here should be that the Drobo is not a &#8220;high availability&#8221; storage array in the modular or enterprise class.  It doesn&#8217;t support mulitple controllers or other features like mirrored cache, so in reality, multiple power supplies is probably over-configuration.  Obviously dual Ethernet connections is essential in a device that will support multiple hosts; this feature provides redundancy from failures in network equipment or more likely, enables maintenance to be performed on the network infrastructure without impacting the storage.</p>
<p>The addition of a power switch is a positive move (and essential as the power supply is now integrated).  Personally I&#8217;d have preferred the power switch to be mounted behind the magnetic bezel on the front of the unit.  This would mean once plumbed in, the &#8216;Elite (and &#8216;Pro for that matter) would be managed purely from the front, for disk insertions/removals.</p>
<p>I&#8217;ve one final comment on the physical aspects of the &#8216;Elite and that covers the insertion and removal of drives.  I never like removing spinning active drives and unfortunately there&#8217;s still no way to either mark a drive for removal or spin it down.  The unique BeyondRAID feature of the Drobo series means that any drive can be removed from a unit and the device &#8216;self heals&#8217; to compensate for the loss of capacity, rebalancing blocks of data redundantly across the remaining drives.  Of course drive removal doesn&#8217;t have to be done after a failure; the whole benefit of the Drobos is the capacity increase functionality (I frequently swap drives in/out as part of testing).  I&#8217;d therefore like to be able to spin down or at least highlight a drive I intended to pull, via software, before I physically pull it.  It gives me more confidence that I&#8217;ve pulled the correct drive when managing multiple units.</p>
<p>Additional specifications can be found here: <a href="http://www.drobo.com/pdf/droboelite-datasheet.pdf" >http://www.drobo.com/pdf/droboelite-datasheet.pdf</a></p>
<p>In the next post, I&#8217;ll look at connectivity protocol support.</p>
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		<title>Personal Computing: Can Drobo Dashboard Manage Multiple Drobos?</title>
		<link>http://thestoragearchitect.com/2010/01/05/personal-computing-can-drobo-dashboard-manage-multiple-drobos/</link>
		<comments>http://thestoragearchitect.com/2010/01/05/personal-computing-can-drobo-dashboard-manage-multiple-drobos/#comments</comments>
		<pubDate>Tue, 05 Jan 2010 19:08:48 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Featured]]></category>
		<category><![CDATA[GestaltIT]]></category>
		<category><![CDATA[Storage]]></category>
		<category><![CDATA[Data Robotics]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[Drobo Dashboard]]></category>
		<category><![CDATA[DroboPro]]></category>
		<category><![CDATA[DroboShare]]></category>
		<category><![CDATA[Mac]]></category>

		<guid isPermaLink="false">http://www.thestoragearchitect.com/?p=1000</guid>
		<description><![CDATA[<p>This is a problem that&#8217;s been on my mind for some time; can the Drobo Dashboard see more than one device at the same time?  Well, it turns out the answer is yes.</p> <p><a href="http://31.222.189.99/wp-content/uploads/2010/01/ScreenShot12341.png" ></a>At first my thought was that it wasn&#8217;t possible for the Drobo Dashboard to manage more than one device.  Currently [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>This is a problem that&#8217;s been on my mind for some time; can the Drobo Dashboard see more than one device at the same time?  Well, it turns out the answer is yes.</p>
<p><a href="http://31.222.189.99/wp-content/uploads/2010/01/ScreenShot12341.png" ><img class="alignleft size-thumbnail wp-image-1017" title="ScreenShot1234" src="http://50.57.85.110/wp-content/uploads/2010/01/ScreenShot12341-150x150.png" alt="ScreenShot1234" width="150" height="150" /></a>At first my thought was that it wasn&#8217;t possible for the Drobo Dashboard to manage more than one device.  Currently I have a Drobo connected into a DroboShare and a shiny new DroboPro, which is serving iSCSI LUNs to my ESX server.  I&#8217;ve not been able to get Drobo Dashboard on my main Windows 7 PC to work correctly.  It seems to have issues seeing the DroboShare.  I&#8217;ve checked all the obvious stuff (like firewalls) but still can&#8217;t get it to work.  Anyway, I was testing connectivity from my MacBook to the DroboPro using USB and to my surprise, both the DroboShare (called Drobo1) and my DroboPro (called DroboNAS2) both appeared in the GUI.  Have a look at the attached graphic.  You can see the Drobos listed at the top of the screen; this can be used to toggle between a display of both devices.</p>
<p>Now this is the Mac version of the Dashboard.  I can&#8217;t vouch for the Windows version as mine clearly doesn&#8217;t work correctly, however I imagine it works the same way.  So the answer to the question; &#8220;Can Drobo Dashboard manage Multiple Drobos?&#8221; is clearly &#8211; Yes.</p>
<p>Oh, one other thing worthy of note; I can confirm that the DroboPro definitely will *not* let me connect to the USB port while it is serving iSCSI LUNs through IP.  That&#8217;s a real shame, as I can&#8217;t manage the device without an outage.  Bit of a showstopper, I think.</p>
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		<title>Review: DroboPro &#8211; Part II</title>
		<link>http://thestoragearchitect.com/2009/12/07/review-drobopro-part-ii/</link>
		<comments>http://thestoragearchitect.com/2009/12/07/review-drobopro-part-ii/#comments</comments>
		<pubDate>Mon, 07 Dec 2009 16:27:33 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Featured]]></category>
		<category><![CDATA[GestaltIT]]></category>
		<category><![CDATA[Reviews]]></category>
		<category><![CDATA[Data Robotics]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[DroboPro]]></category>
		<category><![CDATA[ESXi]]></category>
		<category><![CDATA[ix4-200d]]></category>

		<guid isPermaLink="false">http://thestoragearchitect.com/?p=927</guid>
		<description><![CDATA[<p>This is the second in a series of posts looking at the DroboPro from Data Robotics Inc.  Previous post(s):</p> <p><a href="http://thestoragearchitect.com/2009/12/01/review-drobopro-part-i/" >Review: DroboPro &#8211; Part I</a></p> <p><a rel="nofollow" href="http://thestoragearchitect.files.wordpress.com/2009/12/droboesxiscsi.png" ></a>Previously I discussed a few frustrations with connecting my new DroboPro to ESXi, the target environment for my new device.  I&#8217;ve now managed to get the [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>This is the second in a series of posts looking at the DroboPro from Data Robotics Inc.  Previous post(s):</p>
<p><a href="http://thestoragearchitect.com/2009/12/01/review-drobopro-part-i/" >Review: DroboPro &#8211; Part I</a></p>
<p><a rel="nofollow" href="http://thestoragearchitect.files.wordpress.com/2009/12/droboesxiscsi.png" ><img class="alignright size-medium wp-image-928" title="DroboESXISCSI" src="http://thestoragearchitect.files.wordpress.com/2009/12/droboesxiscsi.png?w=300" alt="" width="300" height="100" /></a>Previously I discussed a few frustrations with connecting my new DroboPro to ESXi, the target environment for my new device.  I&#8217;ve now managed to get the &#8216;Pro connected and visible within ESXi.  See the attached screenshot image taken from my production ESXi server.</p>
<p>So far, I&#8217;ve configured eight 2TB LUNs (although the DroboPro itself only has a capacity of 5TB, 2x 2TB and a single 1TB drive) which are numbered 0-7; the LUN column on the screenshot.  Compare this to the LUNs presented from my ix4-200d, which has three LUNs all numbered &#8217;0&#8242;.  The difference is in the way the DroboPro is choosing to present iSCSI devices and the Runtime Name column gives a clue.  In standard Controller/Target/LUN or CxTyLz/CxTyDz methodology, the ix4 disks are using separate targets to map out each iSCSI LUN, with the LUN number always &#8217;0&#8242;.  The Target setting is analagous to a storage port, typically a physical port on large fibre channel arrays.  The LUNs are then numbered on that port.  The DroboPro presents all its iSCSI LUNs on the same target (in this instance number 3) and so the LUNs are numbered from 0.</p>
<p>This method of presentation doesn&#8217;t necessarily cause a problem, but is just a different way of presenting the LUNs.  Presumably with the Drobo Elite the multi-user functionality is achieved by enabling multiple targets per Drobo, each mapped to a separate user.  In any case, I now have visibility of my DroboPro within ESXi.  Time, to write some data.</p>
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		<title>Personal Computing: Drobo Replacement</title>
		<link>http://thestoragearchitect.com/2009/11/20/personal-computing-drobo-replacement/</link>
		<comments>http://thestoragearchitect.com/2009/11/20/personal-computing-drobo-replacement/#comments</comments>
		<pubDate>Fri, 20 Nov 2009 17:13:27 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Storage]]></category>
		<category><![CDATA[Drive Replacement]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[RAID]]></category>

		<guid isPermaLink="false">http://thestoragearchitect.com/?p=910</guid>
		<description><![CDATA[<p>Following on from my <a href="http://thestoragearchitect.com/2009/10/19/personal-computing-drobo-weirdness/" >Personal Computing: Drobo Wierdness</a>, I have received a replacement unit from Data Robotics.  I thought for a change I&#8217;d produce a video and so here is my attempt to swap out my drives into the new unit.  In the end I formatted the existing drives as four new NAS shares.  [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>Following on from my <a href="http://thestoragearchitect.com/2009/10/19/personal-computing-drobo-weirdness/" >Personal Computing: Drobo Wierdness</a>, I have received a replacement unit from Data Robotics.  I thought for a change I&#8217;d produce a video and so here is my attempt to swap out my drives into the new unit.  In the end I formatted the existing drives as four new NAS shares.  So the unit is back and working. Enjoy.</p>
<p><a href="http://thestoragearchitect.com/2009/11/20/personal-computing-drobo-replacement/"><em>Click here to view the embedded video.</em></a></p>
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		<item>
		<title>Personal Computing: Drobo Weirdness</title>
		<link>http://thestoragearchitect.com/2009/10/19/personal-computing-drobo-weirdness/</link>
		<comments>http://thestoragearchitect.com/2009/10/19/personal-computing-drobo-weirdness/#comments</comments>
		<pubDate>Mon, 19 Oct 2009 13:00:38 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Storage]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[iomega]]></category>
		<category><![CDATA[ix4-200d]]></category>

		<guid isPermaLink="false">http://thestoragearchitect.com/?p=780</guid>
		<description><![CDATA[<p>Hmm, I&#8217;ve found a small bug with my Drobo which is making me slightly nervous.  Have a look at the first graphic.  I&#8217;ve exceeded a single 2TB logical drive in terms of capacity (as I now have two 2TB and two 1TB physical drives installed).  In this instance the Drobo has created me a second logical drive, which [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>Hmm, I&#8217;ve found a small bug with my Drobo which is making me slightly nervous.  Have a look at the first graphic.  I&#8217;ve exceeded a single 2TB logical drive in terms of capacity (as I now have two 2TB and two 1TB physical drives installed).  In this instance the Drobo has created me a second logical drive, which I believe I&#8217;ve relabelled as the W: drive.</p>
<p>Unfortunately it&#8217;s not accessible and requires formatting, which also doesn&#8217;t work.  You can see from the additional screens that the Drobo is getting confused on a rename and won&#8217;t let me change the drive details.</p>
<p>I&#8217;m in the process of getting up to the latest level of code, as it appears I&#8217;m a few steps behind.  I&#8217;m also offloading the data on the Drobo to my new Iomega ix4-200d.  This will hold most of my VMware data, however as it supports Active Directory, I&#8217;m moving my general file shares there too.</p>
<p>Fingers crossed that the code update fixes the problem&#8230;</p>

<a href='http://thestoragearchitect.com/2009/10/19/personal-computing-drobo-weirdness/drobowierd2/' title='DroboWierd2'><img width="150" height="97" src="http://thestoragearchitect.com/wp-content/uploads/2009/10/drobowierd2.png" class="attachment-thumbnail" alt="DroboWierd2" title="DroboWierd2" /></a>
<a href='http://thestoragearchitect.com/2009/10/19/personal-computing-drobo-weirdness/drobowierd3/' title='DroboWierd3'><img width="150" height="126" src="http://thestoragearchitect.com/wp-content/uploads/2009/10/drobowierd3.png" class="attachment-thumbnail" alt="DroboWierd3" title="DroboWierd3" /></a>
<a href='http://thestoragearchitect.com/2009/10/19/personal-computing-drobo-weirdness/drobowierd1/' title='DroboWierd1'><img width="150" height="111" src="http://thestoragearchitect.com/wp-content/uploads/2009/10/drobowierd1.png" class="attachment-thumbnail" alt="DroboWierd1" title="DroboWierd1" /></a>

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		<title>Personal Computing: Drobo Jitters</title>
		<link>http://thestoragearchitect.com/2009/09/14/personal-computing-drobo-jitters/</link>
		<comments>http://thestoragearchitect.com/2009/09/14/personal-computing-drobo-jitters/#comments</comments>
		<pubDate>Mon, 14 Sep 2009 20:44:18 +0000</pubDate>
		<dc:creator>Chris M Evans</dc:creator>
				<category><![CDATA[Storage]]></category>
		<category><![CDATA[Drobo]]></category>
		<category><![CDATA[file protection]]></category>
		<category><![CDATA[RAID]]></category>

		<guid isPermaLink="false">http://thestoragearchitect.com/?p=728</guid>
		<description><![CDATA[<p>As regular readers will know, I&#8217;ve had a <a href="http://www.drobo.com/index.php" >Drobo</a> storage system for some time now.  I&#8217;ve not had a bad word to say about the product &#8211; it just works and does what I expect it to do.  However, there&#8217;s one function I think could do with some improvement and it&#8217;s the one [...]<!--Begin ClixTrac.com Rotator Code -->
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			<content:encoded><![CDATA[<p>As regular readers will know, I&#8217;ve had a <a href="http://www.drobo.com/index.php" >Drobo</a> storage system for some time now.  I&#8217;ve not had a bad word to say about the product &#8211; <strong>it just works</strong> and does what I expect it to do.  However, there&#8217;s one function I think could do with some improvement and it&#8217;s the one thing that scares me most &#8211; <strong>removing drives</strong>.</p>
<p><img class="alignright size-full wp-image-730" title="DroboRemove" src="http://thestoragearchitect.files.wordpress.com/2009/09/droboremove1.png" alt="DroboRemove" width="558" height="472" />I&#8217;ve been reviewing <strong>2TB drives</strong> recently and now they&#8217;re destined to be used in the Drobo to expand my storage footprint.  This means I&#8217;ve been swapping drives in and out of the Drobo as I test them on another PC.  The process for drive removal is quite simple &#8211; just pull it out.  That&#8217;s where the problem lies. </p>
<p>I&#8217;m never keen about just removing a drive and letting the system reconfigure itself.  I see that as a &#8220;hard&#8221; failure which could have been avoided.  Before drive removal, surely it&#8217;s best to logically &#8220;evacuate&#8221; a drive and move the contents in a controlled fashion?  Physical removal must be causing the Drobo to perform rebuilds on data, which means if the other drives have faulty copies, then my data&#8217;s lost.</p>
<p>Have a look at the picture; you can see I&#8217;ve removed a drive and the Drobo is in a state of rebuild.  Fortunately the removed drive only had a 500GB capacity and hadn&#8217;t been in the device long.  Reconstruction of RAID only took about 7 minutes and I was protected again.  However I have swapped drives before and experienced a 13 hour rebuild, during which time data was unprotected. </p>
<p>Maybe I&#8217;m being paranoid, but Drobo guys, please give us a controlled way to remove a drive without forcing a rebuild.  It will help me sleep better at night!</p>
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