IBM Storwize V7000 vs. EMC VNX5500 Storage Systems

89 Fifth Avenue, 7th Floor New York, NY 10003 www.TheEdison.com 212.367.7400

White Paper

Competitive Management Cost Study: IBM Storwize V7000 vs. EMC VNX5500 Storage Systems

April 2012

Printed in the United States of America. Copyright  2012 Edison Group, Inc. New York. Edison Group offers no warranty either expressed or implied on the information contained herein and shall be held harmless for errors resulting from its use. All products are trademarks of their respective owners. First Publication: April 2012 Produced by: Kalicharan Rakam, Senior Analyst, Craig Norris, Writer; Barry Cohen, Senior Analyst, Editor-in-Chief; Manny Frishberg, Editor

Table of Contents Executive Summary ..................................................................................................................... 1 About This White Paper ............................................................................................................. 4 Who Should Read This White Paper ................................................................................... 4 Methodology Overview......................................................................................................... 4 Contents of this White Paper ................................................................................................ 4 Storage Management Costs in the Data Center ..................................................................... 5 Overview of the Products ........................................................................................................... 6 Overview of the Management Consoles ............................................................................. 7 Results Summary ....................................................................................................................... 13 Comparative Management Cost Savings .......................................................................... 15 Results Details ............................................................................................................................ 18 Provisioning .......................................................................................................................... 18 Data Protection ..................................................................................................................... 21 Maintenance and Configuration Changes ........................................................................ 24 Monitoring ............................................................................................................................. 27 Methodology for This Study ................................................................................................... 31 CMCS Methodology............................................................................................................. 31 Laboratory Configuration ................................................................................................... 31 Test Procedures ..................................................................................................................... 33 GUI vs. CLI ............................................................................................................................ 34 Other Considerations ........................................................................................................... 36 How to Use These Results ................................................................................................... 36 Conclusions ................................................................................................................................. 37 Appendices .................................................................................................................................. 38 Appendix I - CMCS Methodology Description................................................................ 38 Appendix II - Terminology Glossary ................................................................................. 42

Executive Summary As it has been the trend over the last decade, organizations must continue to deal with growing data storage requirements with the same or less resources. 1 The growing adoption of storage-as-a-service, business intelligence, and big data results in ever more Service Level Agreements that are difficult to fulfill without IT administrators spending ever longer hours in the data center. Many organizations now expect their capital expense growth for storage to be unstoppable, and see operating expense levers — such as purchasing storage systems that are easy to manage — as the only way to control data storage-related costs. Edison’s Competitive Management Cost Study (CMCS) methodology was designed based on Edison’s research over several years. It quantifies the complexity of managing a storage array in a way that easily translates into operational expense. The present study applies this methodology in comparing the relative complexity and ease-of-use of management consoles for two storage systems built for mid-sized organizations: IBM Storwize V7000 and EMC VNX5500. While the two products compared in this study are both unified storage systems, this study specifically evaluated only their block-based storage features. The results of Edison’s research show that administering the IBM Storwize V7000 system using its management interface is 34 percent less time-consuming in weighted workday savings and 31 percent less complex than managing an EMC VNX5500 system using the Unisphere software interface. These results are displayed graphically in the following graphs.

1

Gartner Expects Mild IT Spending Growth in 2011, Enterprise Storage Forum.com

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 1

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 2

Using storage administrator-workload weighting factors developed by Edison, these time savings can be evaluated in terms of operating expense (OPEX) savings. This assessment demonstrates a 34 percent improvement 2 in storage administrator efficiency from IBM Storwize V7000 over EMC VNX5500. Monetizing these efficiencies can result in cost savings of more than $25,000 per year with IBM Storwize V7000 over EMC VNX5500.

2

Presented in Table 1 of this report: Storwize V7000 CMCS Summary of Results.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 3

About This White Paper This white paper is based on a combination of hands-on evaluation, review of relevant published documents on storage cost of ownership, and reports on data center and storage administrator salaries.

Who Should Read This White Paper This white paper should be read by anyone responsible for choosing storage solutions for their organizations or for making administrative personnel decisions in the data center.

Methodology Overview Edison performed the series of tasks described in this white paper on storage systems from IBM and EMC. The methodology and specifications for the hardware and software evaluated are listed in the section of this paper entitled “Methodology for This Study.” NOTE  The two products compared in this study are both unified storage systems. However, this study specifically evaluated only their block-based storage features.

Contents of this White Paper 

Executive Summary – a summary of the context for and results of Edison’s research.



Storage Management Costs in the Enterprise – overview of the factors affecting storage management costs and a discussion of the products tested in this study.



Overview of the Products – description of the products evaluated in this study and the management software user interface for each.



Results Summary – summary of the overall results of the evaluation.



Results Details – discussion of the results for each task category evaluated.



Methodology for This Study – overview of the methodology Edison used in performing the hands-on research.



Conclusions – summary of the results of Edison’s research.



Appendices – a more detailed discussion of the evaluation methodology and a terminology glossary.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 4

Storage Management Costs in the Data Center Edison Group has developed the Competitive Management Cost Study (CMCS) methodology for applying hands-on research comparing administrative consoles of storage systems to determine how their relative ease of use affects the ownership costs of each system. Edison’s CMCS analyses have been used to evaluate administrative consoles for mid-range storage systems from major vendors such as HP, NetApp, EMC, and now from IBM. New trends and developments, such as uncontrolled capacity growth, virtualization, and facility costs, affect acquisition decisions for storage systems. The exponential growth in capacity requirements is widely acknowledged. Storage virtualization, too, has become accepted as the standard approach for storage systems of all sizes, from Data Robotics, Inc.'s Drobo SOHO arrays to the largest enterprise systems from IBM, EMC, HP, and NetApp. Similarly, server virtualization is being widely deployed: according to executives at VMware, the largest vendor of server virtualization on the x86/x64 platform, there are now more virtual servers running under VMware than physical servers. As for facilities costs, even with increased drive capacities and storage consolidation via virtualization, growing capacity requirements still translate into growing expenses. The inexorable growth of application demand and data retention requirements is driving the need to control the cost of managing storage systems, by far the most significant OPEX cost-control lever that exists. In the years since Edison developed our first CMCS report on managing mid-range systems, many storage vendors have made strides in addressing the costs of management complexity by improving their management software. This report covers a comparison between the currently available IBM Storwize V7000 storage system and EMC VNX.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 5

Overview of the Products The products evaluated for this white paper represent the latest generation of mid-range storage products, designed for medium-sized to enterprise businesses, from IBM and EMC. Data centers frequently deploy Storage Area Network (SAN) storage systems for applications requiring the highest levels of performance, while separately Spotlight on Automated Tiering deploying Network Attached Storage This paper focuses on time and complexity (NAS) for its ease of use and less savings through the management software expensive networking. This approach of the products. Worth noting, though, is adds to complexity, introducing multiple that IBM Storwize V7000 also has features, points of management and creating including automatic tiering, virtualized islands of storage, which have adverse pooling and virtualization of external storage systems, which can make the most impacts on efficiency. Both products evaluated in this study are designed to provide a single solution that is more affordable and less complex to use than higher-end storage. Powered by Intel Xeon processors, both incorporate such advanced technology as virtualized storage, thin provisioning, and tiering to help close the gap between exponential data growth and IT storage budgets.

IBM Storwize V7000 Storwize V7000 combines hardware and software components to help support improved storage efficiency through a single point of control. It is designed to improve application availability and resource utilization via a variety of technologies including thin provisioning, automated tiering, storage virtualization (internally and externally), clustering, replication, multi-protocol support, and a robust, intuitive Graphical User Interface (GUI).

effective use of storage resources, enhancing performance and reducing OPEX. IBM Storwize V7000 allows any combination of supported heterogeneous storage devices to be enlisted in a single virtualized pool that can be accessed regardless of underlying hardware resources. Specific types of data can also be assigned to appropriate types of storage. For instance, data for applications that require extremely fast response times can be assigned to solid-state drives (SSDs), while data requiring less demanding access speeds can be stored on less costly traditional spinning disk drives. Using IBM System Storage Easy Tier technology, frequently-used data can be automatically moved to high performance SSDs based on ongoing performance monitoring. This approach enables an organization to benefit from SSD technology at lower cost than an all-SSD solution, yet without requiring administrators to create and manage storage tier policies. A similar technology from EMC (FAST) is not nearly as granular as EasyTier and, therefore, not as efficient.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 6

The storage system is packaged in 2U rack-mountable enclosures that house up to 24 2.5-inch drives or up to 12 3.5-inch drives. Control enclosures contain drives, redundant dual-active intelligent RAID controllers, dual power supplies, batteries, and cooling components. Expansion enclosures contain drives, switches, power supplies, and cooling components. Control enclosures can be clustered and up to nine expansion enclosures can be attached to a control enclosure, supporting up to 240 drives. Tasks related to out-of-the-box product installation and setup were not evaluated for this study. However, the relative simplicity of the IBM Storwize V7000 initialization is worth noting here. The IBM Storwize V7000 initiation employs a USB dongle: the administrator sets the IP address, inserts the dongle, and initial discovery and provisioning takes place, speeding deployment and reducing initial setup costs.

EMC VNX5500 EMC replaced its former CLARiiON and Celerra product lines with new models under the VNX brand. These new storage systems combine many of the features of CLARiiON and Celerra and include several hardware changes, including an update to the Intel processor in the controller. In addition, EMC has joined the transition from 3.5-inch FC drives to 2.5-inch SAS drives as the new standard for high performance enterprise-class spinning disks. 3 The storage system is packaged in rack-mountable enclosures that house up to 25 2.5inch disk drives or SSDs, or up to 15 3.5-inch drives. Disk Processor Enclosures (DPEs) contain drives, redundant dual-active intelligent RAID controllers, dual power supplies, and dual cooling components. Disk Array Enclosures (DAEs) contain drives, switches, power supplies, and cooling components. Up to nine DAEs can be attached to a DPE, supporting up to 250 drives.

Overview of the Management Consoles Edison Group developed the CMCS analysis with the premise that an efficiently designed, intuitive GUI can reduce the time administrators spend managing storage, as well as the time spent training and refreshing staff. It can also serve to greatly reduce the number and length of calls to support administrative issues.

3

EMC VNX Series also supports optional SSD and associated data tiering in conjunction with the addition of EMC FAST Suite software. Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 7

IBM Storwize V7000 Management Interface A browser-based GUI, the IBM Storwize V7000 management interface is intuitive and easy to navigate. The home page offers four optional views. The default view is the Getting Started screen (Figure 1), a robust graphic interface through which you can view the configuration status and access the means for performing specific tasks.

Figure 1: IBM V7000 Getting Started Screen

The Getting Started screen presents an object-oriented view. Click on any onscreen object to go to management operations and/or stats displays for those items. The screen shown here provides an excellent graphical flow chart of the system components and the steps required to provision storage-to-host systems. This view provides an easy way to confirm physical system resources and components, as well as a gateway to configuring more advanced system features. The Getting Started view additionally provides e-Learning and Information Center links that can provide detailed information on each component in the storage provisioning process. The Storwize V7000 management interface provides an object-oriented view of the system components organized in column format on the left side of each display, as shown in Figure 2 (below). This allows for easy scrolling from component to component.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 8

Positioning the cursor over an individual object will provide drill-down options of available administration tasks for the component depicted by the object.

Figure 2: IBM Storwize Volumes Status & Management View

In this view, the middle of the screen displays system status information for volumes (also commonly referred to as LUNs). The bar graph to the left indicates system capacity (used capacity in blue and total system capacity in black), and a component view is in the middle of the display. Position the cursor over each object to display detailed system information. Detailed information on the drives in each enclosure can be displayed by clicking on a disk shelf in the graphic. Clicking the link below the display presents a table of system statistics. Volumes in the Storwize V7000 system are virtual containers. They are abstracted from physical disk drives (internal to the system or on external virtualized systems) via managed disks and pools and then presented to host servers. The “Volume by Pool” view (shown in Figure 3, below) allows the administrator to see detailed information for each Storwize V7000 volume, including its pool association.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 9

Figure 3: IBM Storwize Volume by Pool View

The display shown in Figure 4 (below) shows an example of the interface used in creating a Volume, which provides options between preset defaults or the flexibility for customized volumes with the Advanced tab.

Figure 4: IBM Storwize Creating a Thin-Provisioned Volume

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 10

EMC Unisphere The management console for the EMC VNX Series, EMC Unisphere, runs solely on a Windows server and allows for the monitoring and management of multiple EMC CLARiiON, Celera, and VNX storage systems from a single console. In addition, EMC Unisphere presents an attractive and informative monitoring dashboard as the default view. The screenshot in 5 (below) shows a dashboard view.4

Figure 5: EMC Unisphere Dashboard

Dashboards provide a status overview for each function on the managed storage systems. Unlike the IBM Storwize V7000 management interface, the Unisphere dashboard offers considerable flexibility in the customization of its displays. A single screen for at-a-glance management and reporting, the Unisphere dashboard gives you instant and actionable knowledge about status and events across the entire storage environment. Properly set up so that all systems have the same username and password, Unisphere’s single sign-on can automatically discover all supported EMC installations in the environment, including VNX, CLARiiON, Celerra, and EMC RecoverPoint SE.

Our test environment contained one new storage system, so the amount of information presented is limited to that system. 4

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 11

Unisphere includes a self-service support ecosystem that is accessible with one-click, task-based navigation, and controls for intuitive, application context-based management. It provides customizable dashboard views, graphics, and data tables that present key information in the context of how you manage storage. The display shown in Figure 6 (below) shows an example of the interface used in creating a LUN.

Figure 6: EMC Unisphere - Create LUN Interface

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 12

Results Summary The results of Edison’s testing (Table 1, below) show that IBM Storwize V7000 demonstrates significant advantages over EMC VNX5500 in the area of management ease and, therefore, in administrative costs.5 Our objective findings show that, overall, managing an IBM Storwize V7000 system with its management interface software is 47 percent less time-consuming and 31 percent less complex over a set of common tasks than managing an EMC VNX system using Unisphere software. Table 1: IBM Storwize V7000 CMCS Summary of Results

IBM Storwize V7000 Task

Time

Steps

EMC VNX 5500 Time

Steps

Provisioning Test Results for Task Category

176

8

IBM Advantage (EMC-IBM)

224

6

56%

43%

IBM Advantage % (EMC-IBM/ABS(EMC)) Workday Savings (IBM Advantage * Weighting Factor)

400

14

301

15

159

12

8%

Data Protection Replication Test Results for Task Category

103

9

IBM Advantage (EMC-IBM)

198

6

66%

40%

IBM Advantage % (EMC-IBM/ABS(EMC)) Workday Savings (IBM Advantage * Weighting Factor)

9%

Maintenance and Configuration Test Results for Task Category

172

12

IBM Advantage (EMC-IBM)

-13

0

5

The Microsoft Excel formulas used in the calculations throughout this document are shown in parentheses next to each title. Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 13

IBM Storwize V7000 Task

Time

Steps

IBM Advantage % (EMC-IBM/ABS(EMC))

-8%

Workday Savings (IBM Advantage * Weighting Factor)

-1%

EMC VNX 5500 Time

Steps

0%

Monitoring Test Results for Task Category

55

2

IBM Advantage (EMC-IBM)

35

2

39%

50%

IBM Advantage % (EMC-IBM/ABS(EMC)) Workday Savings (IBM Advantage * Weighting Factor)

90

4

950

45

5%

Totals Test Results Totals

506

31

Total Time Savings: IBM Advantage (EMC-IBM)

444

14

IBM Advantage % (EMC-IBM/ABS(EMC))

47%

31%

Average Workday Savings (IBM Advantage % * Total Factors tested)

34%

$ Savings6

$25,686

For most IT executives, the best way to appreciate the importance of management cost savings is by examining the findings in the context of OPEX cost savings. The Total Time Savings in the table above is simply a sum of the savings for the tasks evaluated. In general, Edison believes that these raw numbers do not accurately reflect the actual workloads storage administrators’ experience (as reflected in the Average Workday Savings), because they do not include all the tasks they perform during the day. In order to address this, Edison developed a set of workload weighting factors that could be applied to our testing; Edison surveyed storage administrators using storage systems from several vendors, in organizations of all sizes.

6

Average Workday Savings x Salary derived from Table 3: Average Storage Administrator Salaries (page 16). Results are rounded to whole dollar. Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 14

The Edison white paper, Comparative Management Cost Survey: Workload Weighting for Mid-Range Storage Array Administrators, describes the research leading to the identification of the weighting factors. It can be found in the Published Reports Library on the Edison web site at http://www.theedison.com. The factors included in this study are presented in Table 2 (below). Only those appearing in shaded rows (i.e., 74 percent of the total workload weighting factors identified) were factored into the evaluation for the current study. Table 2: Storage Administrator Workload Weighting Factors

Weighting Factors 7 Provisioning

14%

Data Protection

16%

Maintenance

27%

Problem Solving

17%

Application Specific

13%

Overhead

12%

Total factors for tests performed in this study

74%

Average Storage Admin Pay

$76,333

As seen in the Average Workday Savings total in Table 1, when these weighting factors are applied to the raw time-savings test results, IBM Storwize V7000 demonstrated a 34 percent advantage over the EMC VNX5500 system. This is examined more granularly in the Results Details sections of this white paper.

Comparative Management Cost Savings The Edison CMCS methodology assigns a complexity metric to task categories, as well as measuring and comparing the time required to perform different tasks. In most realworld business environments, management costs far outweigh licensing and vendorcharged support costs throughout the life of the product. With this in mind, we estimated the annual cost a business might expect save on storage administrator time resulting from one product being easier to administer and operate than the other.

7

The weighting factors do not add up to 100 percent due to rounding.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 15

In order to compute cost savings, Edison used Storage Administrator salary figures gathered from a query of salaries made at Simplyhired.com8. Edison searched for the salaries in seven metropolitan areas of various sizes and cost-of-living. Though different choices would affect the results, Edison believes the derived average salary is reasonable. Table 3: Average Storage Administrator Salaries

Storage Administrator Salaries New York City

$87,000.00

Atlanta, GA

$ 73,000.00

Houston, TX

$ 71,000.00

St. Louis, MO

$ 69,000.00

Chicago, Il

$ 76,000.00

Phoenix, AZ

$ 66,000.00

Los Angeles, CA

$ 69,000.00

San Francisco, CA

$ 93,000.00

Seattle, WA

$ 83,000.00

Average

$ 76,333.00

The average of the results of this search (Table 3, above), when multiplied by the weighted time savings, show cost savings for IBM Storwize V7000 system versus EMC VNX5500 system: Median Storage Administrator Salary * (Storage Administrator Time Savings) = $76,333 * 34% = $25,686 By substituting its own costs, an organization can determine its potential savings. Edison recognizes that these savings are not going to be realized directly. Instead, they need to be interpreted within the context of overall storage administrator duties and storage group or IT budgets. Within this framework, time savings of over 34 percent can translate to reducing the need for new hires when additional storage systems are acquired, or to enabling a better allocation of resources to mission-critical tasks. It is not practical to attach direct financial costs to complexity. However, it should be apparent that more complex management tools require more user training, can cause user error simply due to that complexity, and can otherwise affect productivity.

8

This and similar queries can be performed at http://www.simplyhired.com/a/salary/home

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 16

These objective differences do not tell the whole story. As is seen elsewhere in this white paper, in most respects performing management tasks with the IBM Storwize V7000 management interface generally provides a better user experience than does EMC Unisphere. Fewer steps and a more intuitive interface reduce the odds of user error in execution.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 17

Results Details Edison compared the performance of four categories of tasks: Provisioning, Data Protection, Maintenance, and Monitoring. Since the architecture and management approaches of the two vendors differ, not all the tasks that comprise a tested category could be compared. Where no equivalent function or task existed for both platforms, the time and complexity rating results were not included in the summarized results. Similarly, some tasks, such as replacing a disk, could not be performed for all of the platforms as the test systems lacked sufficient additional disks. The following sections each contain a description of the task categories, a summary of test results for that category, a listing of the tasks performed and compared, and a subjective appraisal of the user experience.

Provisioning For purposes of this study, provisioning covers tasks performed after the storage system has been installed and initialized. Installation-related tasks were not included for two main reasons: first, a system is only installed once; second, for many organizations, installation is performed by vendor technicians. There are organizations where storage systems are being added to the data center daily but, in such cases, the installation teams are generally vendor-provided technicians or staff dedicated to that task. The tasks evaluated here include those related to preparing connectivity and the storage devices for use by hosts. The following table (Table 4: Provisioning Tasks Comparison, page 20) shows the specific provisioning tasks, using nomenclature for each vendor that Edison evaluated.

Provisioning Tasks and Summary The tasks evaluated for the respective systems were as follows: IBM Storwize V7000 System 

Configure Physical Storage (Internal Storage - Default RAID 5) — Internal storage is the RAID-protected storage that is directly attached to the Storwize V7000 system. The Storwize V7000 system automatically detects the drives that are attached to it. These are configured into RAID arrays, presented as MDisks, which can be added to storage pools in the same way as MDisks that are discovered when external storage systems are added.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 18



Create New Volume (LUN) — A volume is a logical disk that the system presents to the hosts. Volumes can be Generic, Thin, Mirrored, or Thin Mirrored.



Add/Create Hosts — A host system is a computer that is connected to Storwize V7000 through a Fibre Channel interface (IP network is also an option).



Assign/Map Volumes to Hosts — Host mapping is the process of controlling which hosts have access to specific volumes within the system.



Search for Volumes —Previously configured hosts can be mapped to previously configured volumes that are found.

EMC VNX5500 System 

Create Storage Pools (Default RAID 5) – A storage pool is a set of disks all with the same redundancy (RAID 5, RAID 6, or RAID 1/0), on which you create one or more thin or non-thin LUNs.



Create LUN – (RAID 5 default, thin or non-thin).



Create/Add Hosts.



Creating Storage Groups – A storage group is a logical grouping of LUNs and hosts. that enables managing both as a single unit.



Host Assignment to Storage Group.



LUN Assignment to Storage Group.



Search for LUNs.

The Summary of Results for Provisioning in Table 4 (below) shows that, for the compared tasks, the IBM Storwize V7000 system was 56 percent less time-consuming and 43 percent less complex to manage than the EMC VNX5500. Table 4: Provisioning Summary of Results

IBM Storwize V7000 Task

Time

Steps

EMC VNX 5500 Time

Steps

Provisioning Test Results for Task Category

176

8

IBM Advantage (EMC - IBM)

224

6

56%

43%

IBM Advantage % (EMC-IBM/ABS(EMC)) Workday Savings (Difference* Weighting Factor)

400

14

8%

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 19

When the weighting factor is applied, the advantages are smaller, but can be cumulatively significant when these activities are urgent. The two charts below illustrate the differences in provisioning time and complexity for the two platforms.

Figure 7: Provisioning: Time and Complexity Comparisons Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 20

Data Protection Without good data protection capabilities, there is almost no reason to invest in a storage system. Data protection includes such features as multiple controllers, multiple I/O paths, remote replication, and the creation of snapshots and copies. Multiple controllers and I/O paths are dependent upon the physical attributes of the appliance and are generally configured as part of installation. This study does not include an evaluation of the management of the physical controllers and I/O paths. Remote replication was not tested because the Edison lab only had one system from each vendor. That leaves the creation of copies and snapshots. 9 A copy 10 is defined essentially the same way on either platform — an exact replica of existing data on the system managed in the same manner as the source data. Copies can be used as a backup, especially when replicated to a second local or remote storage system. This approach, typically used to enable high availability, usually takes the form of what EMC terms a mirror and IBM calls a mirrored pair, meaning that the data in each copy is regularly updated and synchronized through replication. Copies can be made to retain a relationship with the original data, or not. Copies are also often used in development environments where it is desirable for developers to work with real data, but where using live data would be too risky to allow. A snapshot creates a point-in-time view of the original data. The snapshot is not intended to be an independent copy but is used to maintain a view of the original data at the time the snapshot is created. Therefore, the snapshot holds only the data from regions of the original volume that have changed subsequent to the creation of the snapshot (starting with no data at all). Since the snapshot uses thin provisioning, only the capacity required for the changes is used. Compared to full copies, snapshots require much less additional storage space on an array — typically 10 to 20 percent of the original size, rather than the 100 percent capacity required by a copy. On the EMC product, snapshots are created at the LUN or Vdisk level. For EMC, each LUN can have its own snapshot policies, easily matching the business needs.

9

For in-depth descriptions and explanations of these functionalities in IBM Storwize V7000, documentation can be accessed at: http://publib.boulder.ibm.com/infocenter/storwize/ic/index.jsp?topic=%2Fcom.ibm.storwize.V7000.doc%2F mlt_relatedinfo_224agr.html 10

Often referred to as a clone; though to avoid confusion between product nomenclature, “copy” is used except in explicitly defined instances.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 21

On the IBM product, snapshots are accomplished using a FlashCopy snapshot preset function that creates a point-in-time view of the production data.

Data Protection Tasks and Summary The tasks evaluated for the respective systems were as follows: IBM Storwize V7000 System 

Create Snapshot



Create Copy



Flash Copy Mappings – equivalent to Snap Mirror – maps snapshot to source for updating



Start Snap



Restore Snap/Copy

EMC VNX 5500 Systems 

Create Reserved LUN Pool – to hold snapshots



Creating a Snapshot (SnapView) – sets the parameters for the snapshot



Start Snapshot Session – this creates the snapshot



Add a Snapshot to Storage Group



Activate and Deactivate Snapshots – making it available (or unavailable) to a host (in a Storage Group)



Restoring Snapshot Copies



Configure Clone (Copy) Settings



Creating Snap Clone (Copy)/Mirror

Consistency groups are a notable time-saver in the typical scenario, where applications are associated with multiple LUNs/volumes. Enabling a single, consistent point-in-time copy across multiple volumes, consistency groups are important in scenarios such as a database environment, where obtaining a consistent copy would require a temporary suspension of database operations. Consistency groups allow administrators to group multiple volumes, after which they can create a copy of, or restore, particular groups instead of individual volumes. For example, standard practice with SQL Server would be to have a volume in the Storwize V7000 storage system for data, and logs stored on another volume in order to keep them (and possibly configure them) separately. You can

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 22

combine them into a “SQL Server Consistency Group” and snapshot or copy them as a single entity for such purposes as recovery or development. As can be seen in Table 5 below, when the IBM system is compared to the EMC system, it is 66 percent less time-consuming and 40 percent less complex to manage. Table 5: Data Protection Summary of Results

IBM Storwize V7000 Task

Time

Steps

EMC VNX 5500 Time

Steps

Data Protection Replication Test Results for Task Category

103

9

IBM Advantage (IBM - EMC)

198

6

66%

40%

IBM Advantage % (EMC-IBM/ABS(EMC)) Workday Savings (Difference* Weighting Factor)

301

15

9%

The two charts below show the differences more dramatically by providing a visual indication of differences in data protection time and complexity for the two platforms.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 23

Figure 8: Data Protection: Time and Complexity Comparison

Maintenance and Configuration Changes Maintaining a storage system includes a wide range of activities, including software updates, replacement of failed drives, and so forth. Configuration changes include additional capacity realized by adding drive shelves and drives, changing usage configurations, and the deletion of snapshots and copies for which there is no further use. The Maintenance and Configuration Changes tasks evaluated in this study consist of such activities as deleting outdated snapshots, managing and expanding LUNs, destroying inactive LUNs, and reconfiguring or decommissioning storage pools or aggregates. Other tasks that fit under the topic but that were not evaluated include removing and replacing failed drives, adding additional drives, and so forth.

Maintenance and Configuration Changes Tasks and Summary The tasks evaluated for the respective systems were as follows:

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 24

IBM Storwize V7000 System 

Expand Storage Pool



Delete Storage Pool



Expand Volumes



Delete Volumes



Delete Snapshots



Delete Copies



Search Volumes



Delete Host

EMC VNX5500 System 

Expand Storage Pool



Expand LUNs



Destroying LUNs



Destroying RAID Groups/Storage Pool



Destroying/Deactivating Snapshots



Destroying Clones (Copies)



Deleting Host

Performing tasks may require additional prior tasks. For example, destroying a clone (copy) that is attached to a host requires that it be detached from the host or taken offline before it can be destroyed. The number of different possible scenarios would, if included, add unnecessary complexity to this analysis. The results in Table 6 (below) show that performing these tasks with Unisphere is 8 percent faster than performing the equivalent tasks with the IBM Storwize V7000 management interface. A comparison of the individual tasks reveals that the time difference was due to two factors. First, an additional task, Search LUNS/Volumes was performed on the V7000 that was not tested on the VNX – this added 12 seconds to the total. Second, the time required to expand the storage pool was longer on Storwize V7000 than on the VNX. The resulting 8 percent advantage for VNX is significant, in itself, but when weighting is applied, the resulting 1 percent difference is insignificant.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 25

No appreciable difference in complexity was found between the two management interfaces for these tasks. Table 6: Maintenance and Configuration Changes: Summary of Results

IBM Storwize V7000 Task

Time

Steps

EMC VNX 5500 Time

Steps

Maintenance and Configuration Test Results for Task Category

172

12

IBM Advantage (IBM - EMC)

-13

0

IBM Advantage % (EMC-IBM/ABS(EMC))

-8%

0%

Workday Savings (Difference* Weighting Factor)

-1%

159

12

The following two charts provide a graphic illustration of the performance differences.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 26

Figure 9: Maintenance and Configuration Changes Comparison

Monitoring During the interviews Edison conducted when developing the workload weighting factors, many of the respondents mentioned that their most important activity was monitoring system status. By its nature, monitoring does not require significant effort, but properly configuring monitoring tools both enables timely preventive maintenance and simplifies troubleshooting. Performing troubleshooting tasks most often occur outside of the management interfaces, so were not included in this study. For this study, Edison only compared the management tools provided in the two management consoles, IBM Storwize V7000 and Unisphere. Monitoring tools that required the use of external software were not included. In addition, since monitoring is a passive process by definition, we did not evaluate the use of the monitoring tools themselves. Therefore, we compared only the configuration of monitoring on the two systems. The tasks evaluated for the respective systems were as follows:

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 27

IBM Storwize V7000 System 

Configure Event Notifications – E-mail



Configuring Event Monitoring – SNMP/Syslog



Remote Support/Dial Home

EMC VNX5500 System 

Configuring EMC Event Monitoring – E-mail



Configuring EMC Event Monitoring – SNMP



Configuring Host Notification



Configuring Remote Support

It is important to note that though Edison performed all the tasks for both platforms, not all of the tasks were performed separately on each. For example, with Unisphere, all of the monitoring configuration tasks are performed without using additional utilities. Table 7: Monitoring: Summary of Results

IBM Storwize V7000 Task

Time

Steps

EMC VNX 5500 Time

Steps

Monitoring Test Results for Task Category

55

2

IBM Advantage (IBM - EMC)

35

2

39%

50%

IBM Advantage % (IBM-EMC/ABS(IBM)) Workday Savings (Difference* Weighting Factor)

90

4

5%

The effect of task consolidation is evident in the results in Table 7 (above). Even though there is only one interface required for configuring monitoring on VNX versus two on V7000 (there is a separate interface for configuring remote support), there were twice as many steps required to perform the same activity on VNX and the time difference, near 40 percent, is quite large.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 28

Figure 8: Monitoring Comparison

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 29

Though troubleshooting tasks were not evaluated for this study, the IBM Storwize V7000 management interface has a wizard-based troubleshooting aid, Recommended Actions, which deserves mention, since it can reduce demands on an administrator’s time. Clicking Recommended Actions in the Troubleshooting popup brings up a context-sensitive display appropriate to the detected problem. Selecting an error code or message and clicking on “Run the Fix Procedure” will bring you though the steps involved in addressing the problem, as shown in the example below (Figure 10).

Figure 10: IBM Storwize V7000 Recommended Actions Display

The Recommended Action feature can save administrators from having to search through the Help screen knowledge base to determine how to diagnose and remedy the problem.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 30

Methodology for This Study Edison deployed storage systems from IBM and EMC in a lab within its New York City facility, and then performed a series of management tasks, capturing the steps and time required using the Edison Comparative Management Costs Study methodology. Details about the methodology, as well as the lab configuration and the testing process, are described below.

CMCS Methodology The CMCS methodology was created by Edison to be able to objectively compare the manageability ease-of-use for enterprise technology products. Edison devised the methodology to provide an objective metric for comparing Information Technology management platforms. More subjective metrics, such as those derived from interviews with groups of testers in typical user-experience testing, are excellent for understanding the testers’ preferences at the time of testing, but results vary significantly for different groups of testers and test conditions. Objective metrics based on mouse clicks cannot adequately address issues such as the difference between Wizard-based versus non-Wizard based interfaces. The Edison methodology attempts to address these concerns by establishing a set of rules that can account for complexity and different interface design philosophies. A full description of the methodology can be found in the appendix of this report.

Laboratory Configuration Edison's test lab was configured with systems from IBM and EMC. On the following page, Table 8 lists the storage system models, hardware features, and the licensed software installed in the lab.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 31

Table 8: Lab Configuration

VNX5500 Hardware Model

EMC VNX5500

Storage Processor

Dual Processor (SPA & SPB)

Memory Per Processor

12288 MB

Revision/Flare Code

5.31.0.5.502 Storage

Disk Array Enclosure

0 – 24 Disks (Includes two Hot spares) 1 – 24 Disks (Includes two Hot spares)

Disk Type

300 GB SAS

RAID Configuration

RAID 5

Storage Capacity

Physical Capacity 14.4TB Raw, minus EMC VNX OS Vault space Licensed Software

EMC Unisphere File & Block (Navisphere license included. Unisphere replaces Navisphere at installation). SnapView, SAN Copy IBM Storwize V7000 Hardware Model

Storwize V7000

Revision

6.2.0.3

Memory per Processor

8000 MB Storage

Drive Enclosure

1 – 24 Disks 2 – 24 Disks

Disk Type

300 GB 10K SAS

Storage

Physical Capacity 14.4 TB Raw Licensed Software Storwize Management Software Copy Services – Flash Copy & Remote Copy

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 32

Test Procedures This study focuses on regularly performed administrator tasks. Edison divided the tasks into categories that relate to the tasks typically performed by storage administrators on a daily basis: 11 

Provisioning – Provisioning includes all the tasks or operations performed after installation in order to attach an array to servers and store data. These include global tasks such as creating a storage pool, configuring ports for connectivity to hosts, and the creation LUNs or volumes so the array can actually be put to use.12



Data Protection – Data protection covers such features as the creation of snapshots and copies.



Maintenance and Configuration Changes – Maintenance and Configuration Changes include performing maintenance tasks such as adding additional capacity, cleaning up unneeded snapshots, copies, and so forth.11



Monitoring and Troubleshooting – Monitoring an array consists of identifying performance and operational parameters that affect uptime and performance, setting alerts, and generating reports on status and system condition. Troubleshooting consists of identifying the causes of issues identified through monitoring, or from other sources, such as server administrators or end users concerned about performance or data availability. Only enabling and configuration of monitoring were evaluated in this study.



Overhead or Other – These tasks include such tasks as budget or planning meetings, training, and other activities not directly related to any specific storage array. These activities were not evaluated in this study.

Edison identified tasks under each category and matched them between the platforms compared in this study. Since the vendors use either different nomenclature for the same feature or the same nomenclature for different features, this was a very important first step.12 Administrators rarely perform specific tasks in isolation. Often, the administrator has a goal that requires the performance of a combination of several tasks or operations. To 11

The tasks listed for the categories are illustrative, not inclusive. Not all of the tasks listed were evaluated nor are all possible tasks for a category listed. In addition, these categories are not exclusive: tasks listed for one category may be justifiably perceived as belonging to a different category. 12 See the appendix for a table comparing the equivalent nomenclature for the features and functionality used by each of the vendors.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 33

emulate this approach, Edison further categorized the task list to reflect a goal-oriented approach. This also simplified comparisons where the architectural differences between the two platforms would make task-to-task comparisons difficult or even impossible. Table 9 (below) shows the list of tasks and goals, organized by category. Table 9: Task Categories

Provisioning Baseline Provisioning

Tasks that need to be performed prior to creating usable storage on any storage system.

Preparing Storage

This series of tasks includes the creation of a storage pool from the drives in the system.

Preparing Connectivity

For this study, this series of tasks includes all the operations required for setting up access to FC Hosts on the system. Configuration of other network protocols was not evaluated in this study.

Configuring Usable Storage

This category includes the creation of storage objects that can be attached to a host or server.

Data Protection Creating Snapshots

These tasks include the creation and scheduling of snapshots.

Creating Clones (Copies)

These tasks include the creation of clones.

Replication

These are tasks related to replicating data onto remote storage systems. Replication tasks were not performed during this study.

Maintenance and Configuration Changes Removal of Unused Storage Objects

This includes the deletion of old snapshots or clones, deletion of LUNs, etc.

Monitoring and Troubleshooting Monitoring and Troubleshooting

This includes the performance of a series of tasks related to the identification of problems on the systems. For this study, the comparison focuses on the configuration of monitoring tools.

GUI vs. CLI Edison believes that well designed GUIs can greatly improve the quality of system management, compared to the exclusive use of a command line interface (CLI) or scripting. This is especially true for the less skilled staff usually tasked with day-to-day management.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 34

Edison does not oppose the use of the CLI or scripts, but we believe that for the majority of day-to-day tasks, a GUI can lower training and task-oriented support costs and prevent operator error (both significant factors in administrative efficiency) and thus, cost. In fact, a good GUI should streamline the use of scripts by providing an interface for running and creating scripts through learning or similar capabilities. By enabling the use of scripts for the performance of repetitive tasks while providing access through a GUI, the best features of both approaches can be utilized. Dick Benton, principle consultant at GlassHouse Technologies, Inc., wrote an article on storage staffing published by SearchStorage. The theme of the article is that a traditional measure of storage administrator staffing needs — Terabytes per Full-Time Employee — is almost meaningless. This is because the metric can only be calculated within the context of each individual organization. As a practical matter, TB/FTE can only be used after acquisition and implementation, and then only for analysis of staffing requirements for future expansion of the existing infrastructure. Changing the infrastructure to a different platform changes the basis for TB/FTE calculations.

Getting the Best of Both Approaches As stated in the accompanying subsection, the ideal GUI is one that generates CLI commands to reflect the actions implemented using the GUI. This feature is part of the IBM Storwize V7000 management interface. It is a useful way for administrators to learn the various CLI commands. Additionally, the commands generated by GUI actions may be copied and pasted into a text editor in order to create scripts that can then be executed by the system. In this manner, an administrator can programmatically automate frequently used actions. Doing so could result in still further reducing the time and steps involved in using the IBM Storwize V7000 system over other storage systems. An example of this can be seen in creating LUNs. In EMC Unisphere the Create LUN dialog box (Figure 5, page 10), creating multiple LUNs is simply a matter of entering the number to be created in the “Number of LUNs to Create” field. The IBM Storwize V7000 management interface lacks an equivalent field; though multiple volumes can be created within the “New Volume” dialog box, each instance needs to be added manually. However, if creating volumes is done on a frequent basis, a script can be created using CLI commands generated by the GUI, which can be used to create a specific number of volumes with a single action.

The article lists three things to consider when calculating storage management staffing requirements. The first factor is called “technology factors”, which are the technologies (hardware and software) that require significant training or experience for use. The other two factors, “transaction factors” (the day-to-day tasks performed by storage administrators) and “complexity factors” (“factors that impact a storage administrator's need for skills and the time needed to execute a task”) have a major influence on the technology factor. The easier a technology is to use, the less training or experience is required for its use. Edison employs these same criteria in comparing storage administrator costs in this study.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 35

Other Considerations As mentioned above, this study only considers the effect of greater administrative efficiency on ownership costs. Other factors, such as acquisition costs, space and power utilization, third-party installation, decommissioning, and so forth are not included. There is one other ownership cost factor that is not being directly analyzed but which has a bearing on this study: the importance and nature of planning in implementing complex IT infrastructures. Planning for a SAN implementation requires an analysis not only of how much storage is required (including projected expansion), but also the nature of what is being stored. Such considerations include the existence of Microsoft Exchange, SQL Server, or Oracle databases, how much capacity they require, and what data protection policies are needed for operational and regulatory reasons. At a minimum, SAN planning requires the identification of the hosts to be attached to the system, operating systems and application data to be stored, and any data retention and protection policies in place. Installing any of the systems Edison evaluated requires these minimum planning steps. In the modern organization, there is one constant for storage utilization: the storage capacity required, and the hosts and applications to which it is attached, will change rapidly and often in unanticipated ways. If a storage system offers insufficient flexibility to accommodate the rapidly changing environment into which it is placed, the costs of administration can grow very quickly. A system that requires adherence to an overly structured planning process and storage schema can prove very difficult to adapt to changing circumstances. A highly flexible system will enable rapid IT responsiveness to business changes and lower the costs accrued from those changes.

How to Use These Results White papers such as this one are intended to help readers make product acquisition decisions. For midmarket storage arrays, the purchase decision must include many factors. Mid-size organizations often have relatively smaller IT organizations, with administrators wearing many hats. The more efficient the administrator’s toolset, the more productive the administrative staff can be. When reviewing these results, consider the organization’s file storage and application integration requirements. Review staffing policies as well, including training programs and other factors. Also, evaluate the skill levels of existing staff. If the team has great skills and deep knowledge of storage management issues, the choice of storage system management tools may seem moot; but a more efficient platform can enable teams to make better use of their time. Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 36

Conclusions The inevitable increase in storage capacity requirements, along with other factors (including the continued adoption of server virtualization), drives organizations to acquire additional storage systems or to expand the systems they have. The ongoing capital expenditure costs are not going away in the foreseeable future. Therefore, organizations seeking to control costs must look at the OPEX costs associated with managing their ever-growing storage hardware deployments. The IBM Storwize V7000 management interface delivers a compelling savings in OPEX through its highly efficient management capabilities. Edison testing has shown savings of over 47 percent in administrator time and 31 percent less complexity versus performing the same set of tasks with EMC Unisphere. If workload-weighting factors are applied to these results, the savings can be monetized in average administrator time savings of more than $25,000 per year (34 percent of an administrator’s time) with the IBM Storwize V7000 management interface over EMC Unisphere. Edison believes that, for organizations in need of a mature, stable storage platform for mid-range enterprise applications, the IBM Storwize V7000 management interface provides a superior combination of capabilities at a lower OPEX cost than does the EMC VNX5500.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 37

Appendices Appendix I - CMCS Methodology Description The Methodology Defined Edison Comparative Manageability Cost Studies methodology is a product manageability cost-evaluation process. Products in question are compared against a set of task-oriented objective and subjective metrics in order to derive an accurate set of analytical results. The outcome of this study determines the Comparative Management Cost (CMC) incurred by managing and operating the products in a production environment. The methodology employed to conduct this comparison consists of the following elements:

The Study The study is the baseline checklist of standard administration tasks performed routinely, compared quantitatively and qualitatively to determine, on a task-by-task basis, which product is superior, primarily in terms of ease of administration. Certain tasks are also measured in terms of system speed-of-execution — the wall-clock time it takes for the system to complete a job once it has been submitted by an administrator. The function of this study is to derive a meaningful set of CMCS statistics that can reveal the real difference in management costs for the products in question. To do this, CMCS is used to apply a set of quantitative metrics, developed by Edison Group, to a list of tasks typically regarded as qualitative in nature. Tasks Edison defines a task as a complete logical activity, composed of one or more steps, which together significantly alter the state of the device or software program that accomplishes a specific work goal. Each task is measured for time and complexity. Time and complexity, as used in the study, are defined as follows: Time The amount of time it takes to perform a given task. For asynchronous tasks, where a job can be run in the background while the administrator is accomplishing other things, time is measured strictly in terms of how long it takes the administrator to perform the steps to configure, initiate, and submit a given task.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 38

Other (synchronous) tasks in the study demand the administrator’s full attention and prevent the accomplishment of other tasks (as in performing a hot recovery operation on a live database). In that case, time includes both the time it takes for an administrator to configure/execute the task in question and the time it takes the system to complete the task. All time metrics are measured in wall-clock time. Complexity Complexity is measured using a proprietary metric devised by Edison Group: the number of system-affecting steps it takes to complete a given task. A step is defined as a task component that effects a change of state to the system under test. Because not all steps have the same inherent complexity, each step is further broken down into increments to account for the difference. An increment is a decision point that the user must make to complete a step. Increments are technically defined as a part of a step that will have a measurable effect on the state or execution path, but which does not itself affect a change upon the underlying system state until the step is complete. For example, selecting Basic vs. Advanced Install with the installation wizard is an increment, not a step. 

Complexity is then measured in terms of number of steps, but taking into account the following factors: 

The number of increments it takes to complete each step.



Whether or not instrumentation for a given step is GUI-based or requires the use of a command line/scripting interface.



Whether or not the task requires a context switch between multiple interfaces in order to be completed. If a context switch exists, then additional steps will be added to the total step-count for a given task.

The above factors affect the complexity calculation as follows: The primary measure is steps. If a step has many increments, it is considered several steps. The metric allows each step five increments, and we add steps for each additional five increments, rounded up. So if a step has between zero and five increments, it remains unchanged; if it has between six and 10 increments, it is increased by one; between 11 and 15 increments, it is increased by two, and so on. We decided to do this because, while increments are secondary to steps in determining complexity, they do modify the relative complexity of a given step in the course of completing a task. In other words, steps with a low number of increments are simple, and steps with a high number of increments are complex.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 39

The other modifiers (instrumentation and context switching) may occur very infrequently in the products under review. Still they are significant enough factors that we needed to account for them in some meaningful way to generate a measure of complexity that accurately reflects our experience of using the products. Regarding instrumentation, if an operation could be executed entirely within a GUI interface, then the complexity/step value for that task would remain unmodified. If, on the other hand, a step required the use of a command line interface, this would increase the step count. For a simple single-line command operation, the step count was increased by one. Where the operation required the user to write a script, the step value was increased by two or more, depending on how much work was required to write the script in question. Lastly, we come to the matter of context switching. If a context switch was encountered during the course of completing a given task, then two or more steps were added to the step count for that task. The possible addition of more than two steps was allowed for as a judgment call on the part of the subject-matter expert performing the task under consideration. We regard tasks containing context switches, which require understanding the dependencies of relating and performing a single operation in two different environments, as inherently more complex than performing a similar task when operations can be accomplished in one place. The following is the complexity formula utilized throughout these studies.

Complexity Calculation Formula Complexity is defined as the number of computed steps it takes to complete a given task. The formula Edison typically uses to compute complexity for each of the tasks in this study is as follows: For every five increments contained in a step, we increase the step value by one. For example: If a step has 0–5 increments, step value = step + 0, If a step has 6–10 increments, step value = step + 1 If a steps has 11–15 increments, step value = step + 2 … and so on. The type of instrumentation offered to perform a given task modifies the task’s complexity. If a task can be performed completely with a GUI, then step count = step count + 0. Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 40

If a task requires the use of a command line interface, then step count is modified as follows: If the command line operation consists of a single-line command, then step count = step count + 1. If the command line operation requires writing a script, then step count = step count + 2 or more steps, depending on a subjective assessment of the complexity of the script. If a task requires a context switch between different environments, then step count = step count + 2 or more steps, depending on a subjective assessment of the complexity of the context switch.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 41

Appendix II - Terminology Glossary This table lists the equivalent feature nomenclature for the operations and tasks evaluated in this white paper. The list covers the two vendors with a brief description of the core functionality and descriptions for each vendor’s implementation of that functionality. The cell will be blank if the vendor lacks an equivalent feature. IBM Storwize V7000

EMC VNX5500

Description

Physical Storage Physical storage is used to configure and manage storage pools, internal and external storage, and MDisks, and to migrate existing storage to the system.

Storage Pool A storage pool is a means of storage allocation from any type of disk and can incorporate multiple tiers (Flash, FC, and SATA) in the same pool. Storage pools are defined by an administrator before the creation of any LUNs. LUNs can be created at pool level; these pool LUNs are no longer bound to a single storage tier and can be spread to different storage tiers within the same pool.

Some or all of disks in a system, collected into a unit of or for virtual space. (The characteristics of such collections vary with vendor).

RAID Groups A RAID group is a type of storage pool. It is a set of disks with a RAID type on which you create one or more LUNs with the same RAID type. The LUN is distributed equally across all the disks in the RAID group.

RAID group is the actual container for data protection, where multiple LUNS or volumes are created and assigned to a host.

Internal Storage Internal storage is the RAID-protected storage that is directly attached to the Storwize V7000 system. Storage Pool A storage pool is a collection of MDisks that jointly contain all of the data for a specified set of volumes. MDisks A managed disk (MDisk) is a logical unit of physical storage. MDisks are either arrays (RAID) from internal storage, or volumes from external storage systems. MDisks are not visible to host systems.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 42

IBM Storwize V7000

EMC VNX5500

Description

Volume A volume is a logical disk that the system presents to the hosts. MDisks in a pool are split into "extents" of the same size. Volumes are created from the extents that are available in the pool. There are three types of volumes: striped, sequential, and image. Application servers on the SAN access volumes, not MDisks or drives. To keep a volume accessible even when an MDisk on which it depends has become unavailable, a mirrored copy can be added to a selected volume. Each volume can have a maximum of two copies. Each volume copy is created from a set of extents in a storage pool.

LUN A logical unit number (LUN) is a unique identifier used to designate individual or collections of disk devices for address by a protocol associated with a SCSI, iSCSI, Fibre Channel (FC), or similar interface.

LUN or volume is a logical disk created from a storage pool and assigned to host. A LUN could reference an entire RAID set, a single hard disk, or multiple disks.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 43

IBM Storwize V7000

EMC VNX5500

Description

Thin Provisioned Volumes When you create a volume, you can designate it as thinprovisioned. A thinprovisioned volume has a virtual capacity plus a real capacity.

Thin LUN A pool LUN with a thin property. A thin LUN is able to have a subscribed user capacity that is greater than the user capacity of the shared pool.

Virtual provisioning/thin provisioning is a strategy for efficiently managing space in a storage area network (SAN) by allocating physical storage on an "as needed" basis. This strategy gives a host, application, or file system the illusion that it has more storage than is physically provided. Physical storage is allocated only when the data is written, rather than when the application is initially configured.

Virtual capacity is the volume storage capacity that is available to a host. Real capacity is the storage capacity that is allocated to a volume copy from a storage pool. In a fully allocated volume, the virtual capacity and real capacity are the same. In a thinprovisioned volume, however, the virtual capacity can be much larger than the real capacity.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 44

IBM Storwize V7000

EMC VNX5500

Description

FlashCopy FlashCopy software lets you make an instant, point-in-time copy from a source volume to a target volume. Without it, if the data set changes during the copy operation, the resulting copy might contain data that is not consistent. More advanced FlashCopy functions allow operations to occur on multiple source and target volumes. FlashCopy management operations are coordinated to provide a common, single point-intime for copying target volumes from their respective source volumes. This creates a consistent copy of data that spans multiple volumes. The FlashCopy function also allows multiple target volumes to be copied from each source volume. This can be used to create images from different points in time for each source.

Rollback/Restore Snapshot or Clones If the rollback is performed while a snapshot is still active to this session, the snapshot writes will be copied to the source LUN. If the snapshot is deactivated, the original session data will be copied to the source LUN.

Snapshots/Copies are part of data protection, used in creating an instant, pointin-time copy of the source volumes or LUNS. It is difficult to make a consistent copy of a data set that is constantly updated; point-in-time copy techniques help solve this problem.

Snap View SnapView software lets you create local point-intime snapshots and complete data copies (clones) for testing, backup, and recovery operations.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 45

IBM Storwize V7000

EMC VNX5500

Snapshot The snapshot preset creates a point-in-time view of the production data. A snapshot is not intended to be an independent copy, but is used to maintain a view of the production data at the time that the snapshot is created. Therefore, the snapshot holds only the data from regions of the production volume that have changed since the snapshot was created.

SnapView Snapshot The defined virtual device that is presented to a host and enables visibility into running sessions. The snapshot will be defined under a source LUN in such a way that activation of that snapshot will only be allowed on any running sessions belonging to that same source LUN. A snapshot can only be assigned to a single session; thus, to have two active snapshots for the same source LUN, you must have two separate sessions running in which to activate two separate snapshots. Active snapshots are fully read and write-capable. Once the snapshot is deactivated, however, all writes to the snapshot will be deleted.

Clone The clone preset creates an exact replica of the volume, which can be changed without impacting the original volume. After the copy operation completes, the mapping that was created by the preset is automatically deleted. Backup The backup preset creates a point-in-time replica of the production data. After the copy operation completes, the backup view can be refreshed from production data with minimal copying of data from the production volume to backup volume.

Description

SnapView Clone Snap View clones are fully populated point-in-time copies of LUNs that allow incremental synchronization between source and destination LUNs.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 46

IBM Storwize V7000

EMC VNX5500

Description

Reserved LUN Pool Collection of LUNs used to support the pointer-based design of SnapView. As the first SnapView session is started on a given source LUN, a reserved LUN is assigned to the source LUN. If a SnapView session runs long enough for the assigned reserved LUN to be filled, the next available LUN in the reserved LUN pool will be assigned to the source LUN. Reserved LUNs are thus assigned on a persource-LUN basis, such that source LUNs have a one-to-many relationship to their reserved LUNs. Server writes made to an activated snapshot are also stored on a reserved LUN in the global reserved LUN pool. When you deactivate the snapshot, the reserved LUN space is freed and all snapshot writes are destroyed.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 47

IBM Storwize V7000

EMC VNX5500

FlashCopy Mappings A FlashCopy mapping defines the relationship between a source volume and a target volume. The FlashCopy feature makes an instant copy of a volume at the time that it is started. To create an instant copy of a volume, one must first create a mapping between the source volume (the disk that is copied) and the target volume (the disk that receives the copy). The source and target volumes must be of equal size.

SnapView Session This is the process of defining the point-in-time designation by invoking copy-on-first-write activity for updates to the source LUN. Starting a session assigns a reserved LUN to the source LUN if no other sessions are running on this same source LUN. Note that as far as this session is concerned, until a snapshot is activated, the point-in-time copy is not visible to any servers. However, we are tracking the source LUN so we can, at any time in the future, activate a snapshot to this session in order to present the point-in-time image (when the SnapView session was started) to a host. As noted earlier, each source LUN can have up to eight sessions.

Description

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 48

IBM Storwize V7000

EMC VNX5500

FlashCopy Consistency Groups A consistency group is a container for mappings. Many mappings can be added to a consistency group. Enabling a single, consistent point-in-time copy across multiple volumes, consistency groups are important in scenarios, such as a database environment, where obtaining a consistent copy would require a temporary suspension of database operations.

Storage Group A storage group is a logical grouping of hosts and LUNS. The Storage Group option lets you place LUNs and hosts into a group so that the designated LUNs are accessible only to the particular hosts included in the storage group.

Description

The consistency group is specified when the mapping is created. The consistency group can also be changed later. When using a consistency group, prepare and start that group instead of the individual mappings. This process ensures that a consistent copy is made of all the source volumes. Mappings to control at an individual level are known as stand-alone mappings.

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 49

IBM Storwize V7000

EMC VNX5500

Remote Replication The Metro Mirror and Global Mirror Copy Services features enable IT administrators to set up a relationship between two volumes, so that updates that are made by an application to one volume are mirrored on the other volume. The volumes can be in the same system (usually only for testing purposes) or on two different systems (usually at different physical locations).

RecoverPoint is a single solution that provides host-based and arraybased solutions while replicating data from any SAN-based array to any other SAN-based array over existing Fibre Channel or IP network. It provides the ability to go back in time and recover data in a consistent state. It provides support for heterogeneous storage, hosts, networks, and SANs.

Description

Edison: Comparing Management Costs for IBM Storwize V7000 and EMC VNX5500

Page 50