Microsoft SQL Server 2008 on EMC VNXe · PDF fileMicrosoft SQL Server 2008 on EMC VNXe Series...

Microsoft SQL Server 2008 on EMC® VNXe™ Series

Deployment Guide h8286

2

Microsoft SQL Server 2008 on EMC VNXe Series Deployment Guide

Copyright © 2011 EMC Corporation. All rights reserved.

Published September, 2011

EMC believes the information in this publication is accurate as of its publication date. The information is subject to change without notice.

The information in this publication is provided as is. EMC Corporation makes no representations or warranties of any kind with respect to the information in this publication, and specifically disclaims implied warranties of merchantability or fitness for a particular purpose. Use, copying, and distribution of any EMC software described in this publication requires an applicable software license.

EMC2, EMC, Data Domain, RSA, EMC Centera, EMC ControlCenter, EMC LifeLine, EMC OnCourse, EMC Proven, EMC Snap, EMC Source-One, EMC Storage Administrator, Acartus, Access Logix, AdvantEdge, AlphaStor, ApplicationXtender, ArchiveXtender, Atmos, Authentica, Authentic Problems, Automated Resource Manager, AutoStart, AutoSwap, AVALONidm, Avamar, Captiva, C-Clip, Celerra, Celerra Replicator, Centera, CenterStage, CentraStar, ClaimPack, CLARiiON, ClientPak, Codebook Correlation Technology, Common Information Model, Configuration Intelligence, Configuresoft, Connectrix, CopyCross, CopyPoint, CX, Dantz, DatabaseXtender, Data Domain, Direct Matrix Architecture, DiskXtender, DiskXtender 2000, Document Sciences, Documentum, elnput, E-Lab, EmailXaminer, EmailXtender, Enginuity, eRoom, Event Explorer, FarPoint, FirstPass, FLARE, FormWare, Geosynchrony, Global File Virtualization, Graphic Visualization, Greenplum, HighRoad, HomeBase, InfoMover, Infoscape, Infra, InputAccel, InputAccel Express, Invista, Ionix, ISIS, Max Retriever, MediaStor, MirrorView, Navisphere, NetWorker, nLayers, OnAlert, OpenScale, PixTools, PowerPath, PowerSnap, QuickScan, Rainfinity, RepliCare, RepliStor, ResourcePak, Retrospect, RSA, SafeLine, SAN Advisor, SAN Copy, SAN Manager, Smarts, SnapImage, SnapSure, SnapView, SRDF, StorageScope, SupportMate, SymmAPI, SymmEnabler, Symmetrix, Symmetrix DMX, Symmetrix VMAX, TimeFinder, UltraFlex, UltraPoint, UltraScale, Unisphere, Vblock, VMAX, VPLEX, Viewlets, Virtual Matrix, Virtual Matrix Architecture, Virtual Provisioning, VisualSAN, VisualSRM, Voyence, WebXtender, xPression, xPresso, YottaYotta, the EMC logo, the RSA logo, and where information lives are registered trademarks or trademarks of EMC Corporation in the United States and other countries. All other trademarks used herein are the property of their respective owners.

For the most up-to-date regulatory document for your product line, go to the technical documentation and advisories section on Powerlink.

Microsoft SQL Server 2008 on EMC VNXe Series

Deployment Guide

h8286


3

Contents

Chapter 1 Introduction to EMC VNXe Series ................................. 13

EMC VNXe series overview ............................................................................. 14 Software suites available ................................................................................ 14 Software packs available ................................................................................ 14

VNXe application awareness.......................................................................... 14 Advantages of VNXe platforms......................................................................... 15

VNXe high-availability architecture ................................................................ 16 Active-active clustering ................................................................................... 16 No single points of failure ............................................................................... 16 RAID group hot spares .................................................................................... 17 Array-based data replication ........................................................................... 17

VNXe storage pools ........................................................................................ 17 Default storage pools ..................................................................................... 17 Custom storage pools ..................................................................................... 18

Application-based provisioning overview ...................................................... 18

Chapter 2 Microsoft SQL Server Planning on VNXe......................... 21

Overview of SQL Server .................................................................................. 22

Storage for SQL Server ................................................................................... 22 Performance planning for SQL Server ............................................................... 22 Capacity planning for SQL Server ..................................................................... 24

Select the VNXe platform ............................................................................... 25

Summary ........................................................................................................ 26

Chapter 3 Physical Storage Allocation on VNXe: Storage Pools ......... 27

Provisioning overview .................................................................................... 28 Create custom storage pools ........................................................................... 28

Chapter 4 VNXe Connectivity Configuration ................................. 33

Overview ........................................................................................................ 34

Configure VNXe iSCSI target ........................................................................... 34

Contents


4

Configure host entry ....................................................................................... 38

Chapter 5 SQL Server Storage Provisioning.................................. 43

Create iSCSI storage overview ........................................................................ 44 Configure generic iSCSI storage for SQL Server.................................................. 44

Chapter 6 SQL Server Connectivity Configuration .......................... 49

Set up a Windows host to use VNXe iSCSI storage......................................... 50 Connect host to VNXe storage.......................................................................... 50 Configure multiple connections per session...................................................... 54

Volume configuration ..................................................................................... 58 Create and configure disk volumes .................................................................. 58

Chapter 7 Management of SQL Server on VNXe............................. 63

Monitor and manage SQL Server environment ............................................... 64 Expand storage pools ..................................................................................... 64 Extend an existing virtual disks ....................................................................... 66 Add virtual disks to existing deployments......................................................... 66 Extend the storage volume on the host server ................................................... 67

Chapter 8 Replicating SQL Server Data Using VNXe........................ 69

Protection technologies ................................................................................. 70 Snapshots ..................................................................................................... 70 Replication .................................................................................................... 70 Consistency ................................................................................................... 72 Data protection for Microsoft SQL Server .......................................................... 72 Replication Manager....................................................................................... 73

Configure data protection .............................................................................. 73 Establish replication trust ............................................................................... 74 Create replication destination storage .............................................................. 75 Install and configure Replication Manager ........................................................ 79 Create an application set ................................................................................ 80 Create a replication job ................................................................................... 83 Run a replication job through Replication Manager............................................ 87 Replication Manager replicas .......................................................................... 88

SQL Server disaster recovery.......................................................................... 93 Remote SQL Server and database .................................................................... 93 Attach the database ....................................................................................... 93 Fail back to production site ............................................................................. 94 Promote to production instead of failover ......................................................... 94

Data protection and SQL Server performance ................................................ 95

Contents


5

Appendix A Adding a Hot Spare .................................................. 97

Add a hot spare .............................................................................................. 98

Appendix B iSCSI Snapshot Sizing .............................................. 101

Snapshot overview....................................................................................... 102

Calculate space requirements...................................................................... 102

Appendix C System Comparison and Limits ................................... 105

Model components and limits...................................................................... 106

Software configuration limits ....................................................................... 106

Appendix D VNXe Performance with SQLIO Tool .............................. 109

Storage performance overview..................................................................... 110

SQLIO and simulated workload.................................................................... 110

Contents


6


7

Figures

Figure 1. VNXe management dashboard ........................................................ 18 Figure 2. Open Storage Pools page ............................................................... 28 Figure 3. Opening the Disk Configuration Wizard............................................ 28 Figure 4. Select disk configuration mode ....................................................... 29 Figure 5. Specify Pool name ......................................................................... 29 Figure 6. Select storage type ........................................................................ 30 Figure 7. Select number of disks ................................................................... 31 Figure 8. iSCSI Server Settings...................................................................... 34 Figure 9. Add iSCSI Server button ................................................................. 35 Figure 10. iSCSI server dialog box ................................................................... 36 Figure 11. Server Summary page .................................................................... 36 Figure 12. iSCSI Server Details........................................................................ 37 Figure 13. iSCSI Server Details with changes added ......................................... 38 Figure 14. Selecting the Hosts dialog box ........................................................ 38 Figure 15. Hosts window................................................................................ 39 Figure 16. Enter name and description ............................................................ 39 Figure 17. Select operating system ................................................................. 40 Figure 18. Add network address of host .......................................................... 40 Figure 19. iSCSI Access page.......................................................................... 41 Figure 20. Unisphere Dashboard .................................................................... 44 Figure 21. Configure storage pool ................................................................... 45 Figure 22. Select snapshot protection ............................................................. 46 Figure 23. Configure snapshot schedule.......................................................... 47 Figure 24. Configure protection size ................................................................ 47 Figure 25. Configure host access .................................................................... 48 Figure 26. iSCSI Initiator Properties................................................................. 51 Figure 27. Discover Target Portal..................................................................... 51 Figure 28. iSCSI target added ......................................................................... 52 Figure 29. Connect to a target......................................................................... 52 Figure 30. Connect to Target dialog box........................................................... 53 Figure 31. Advanced Settings dialog with default values................................... 53 Figure 32. iSCSI target ................................................................................... 54 Figure 33. Multiple Connected Session (MCS) dialog box.................................. 55 Figure 34. Add Connection dialog box ............................................................. 55 Figure 35. MCS add connection Advanced Settings .......................................... 56 Figure 36. New connection added................................................................... 57 Figure 37. Devices: iSCSI-connected disks ...................................................... 58 Figure 38. Disk Management .......................................................................... 59 Figure 39. Select Initialize Disk....................................................................... 59

Figures


8

Figure 40. Initialize Disk dialog box ................................................................ 60 Figure 41. Create new simple volume .............................................................. 60 Figure 42. Specify Volume Size....................................................................... 61 Figure 43. Select a drive letter ........................................................................ 61 Figure 44. Select drive format settings ............................................................ 62 Figure 45. Completing the New Simple Volume Wizard ..................................... 62 Figure 46. Add drives to the existing pool ........................................................ 65 Figure 47. Select number of drives to add........................................................ 65 Figure 48. Generic storage Details page .......................................................... 66 Figure 49. Extend an existing volume .............................................................. 67 Figure 50. Extend Volume Wizard ................................................................... 68 Figure 51. Replication process........................................................................ 71 Figure 52. Replication Connections page ......................................................... 74 Figure 53. Add Replication Connection Wizard ................................................. 75 Figure 54. Generic iSCSI Storage page............................................................. 76 Figure 55. Specify Name ................................................................................ 76 Figure 56. Configure Storage page .................................................................. 77 Figure 57. Configure protection page .............................................................. 77 Figure 58. Configure protection storage size page ............................................ 78 Figure 59. Configure host access .................................................................... 78 Figure 60. Adding Hosts................................................................................. 80 Figure 61. Create an application set ................................................................ 81 Figure 62. Application Credentials .................................................................. 81 Figure 63. Application Set Name and Objects page .......................................... 82 Figure 64. Completing the Application Set Wizard page .................................... 83 Figure 65. Job Wizard..................................................................................... 83 Figure 66. Job Name and Settings page ........................................................... 84 Figure 67. Target replication storage page ....................................................... 85 Figure 68. Mount Options .............................................................................. 85 Figure 69. Starting the Job page with schedule................................................. 86 Figure 70. Users to be notified........................................................................ 87 Figure 71. Run a replication job ...................................................................... 87 Figure 72. View Replication Manager Snapshots .............................................. 88 Figure 73. Mount a replica ............................................................................. 88 Figure 74. Restore Wizard .............................................................................. 89 Figure 75. Objects to be Restored page ........................................................... 90 Figure 76. Restore Options ............................................................................. 91 Figure 77. Replication Failover........................................................................ 91 Figure 78. Failover dialog box ......................................................................... 92 Figure 79. Promote Replica dialog box ............................................................ 93 Figure 80. Run a database check in SQL Server ................................................ 94 Figure 81. Storage Pools page ........................................................................ 98 Figure 82. Select Configuration Mode page...................................................... 99 Figure 83. Configure Spares page ................................................................... 99 Figure 84. Summary page ............................................................................ 100 Figure 85. Results page ............................................................................... 100


9

Tables

Table 1. Default storage pools ..................................................................... 18 Table 2. PerfMon parameters....................................................................... 23 Table 3. RAID types available on VNXe ......................................................... 23 Table 4. Impact of RAID type on IOPS ........................................................... 24 Table 5. RAID type impact on capacity .......................................................... 25 Table 6. Transactional performance of VNXe platforms .................................. 26 Table 7. VNXe model components and limits .............................................. 106 Table 8. Software configuration limits ........................................................ 106 Table 9. SQLIO performance for 8K random I/O in IOPS................................ 110

Tables


10


11

About this Document

This document provides an overview of the deployment options for Microsoft SQL Server 2008 with EMC VNXe series developed by the EMC Unified Storage Solutions group.

Purpose This document describes how to use the VNXe wizard-driven provisioning interface to create storage for Microsoft SQL Server 2008. It covers common administrative questions in a SQL environment and provides easy-to-use sizing guidelines for such a deployment. Audience This document is intended for internal EMC personnel, EMC partners, and customers. The user is expected to have administrative-level knowledge of Microsoft SQL, and basic knowledge of IP networking. Knowledge of iSCSI source-target configuration is helpful but not required.

Scope This document covers the wizard-driven provisioning interface for SQL environments on the VNXe platform. It covers basic storage sizing and configuration for SQL. It does not cover server-level deployment, infrastructure design, or any non-storage sizing considerations.

Related documents The following documents, located on EMC Powerlink, provide additional, relevant information. Access to these documents is based on the login credentials. If you do not have access to the following documents, contact your EMC representative:

• VMware vSphere 4.1 on EMC VNXe Series — Deployment Guide

• Microsoft Windows Server 2008 R2 Hyper-V on EMC VNXe Series —Deployment Guide

• EMC Unisphere for VNXe: Next-Generation Storage Management —A Detailed Review

• Sizing Considerations for iSCSI Replication on EMC Celerra —Technical Note

About this Document


12


13

Chapter 1 Introduction to EMC VNXe Series

This chapter presents the following topics:

EMC VNXe series overview ............................................................ 14

VNXe application awareness ......................................................... 14

VNXe high-availability architecture .................................................. 16

VNXe storage pools ..................................................................... 17

Application-based provisioning overview .......................................... 18

Introduction to EMC VNXe Series


14

EMC VNXe series overview The EMC® VNXe™ series delivers exceptional flexibility for the small-to-medium business user, combining a unique, application-driven management environment with a complete consolidation for all IP storage needs. Customers can benefit from the new VNXe features such as:

• Next-generation unified storage, optimized for virtualized applications.

• Capacity optimization features including file deduplication and compression, thin provisioning, and application-consistent snapshots and replicas (only available for VNXe for File).

• High availability, designed to deliver five 9s availability.

• Multiprotocol support for file and block.

• Simplified management with EMC Unisphere™ for a single management interface for all file, block, and replication needs.

Software suites available • VNXe Local Protection Suite — Practices safe data protection and

repurposing.

• VNXe Remote Protection Suite — Protects data against localized failures, outages, and disasters.

• VNXe Application Protection Suite — Automates application copies and proves compliance.

• VNXe Security and Compliance Suite — Keeps data safe from changes, deletions, and malicious activity.

Software packs available • Total Efficiency Pack — Includes all five software suites (not available for the

VNX5100™ and VNXe series).

• Total Protection Pack — Includes local, remote, and application protection suites (not available for the VNXe3100™).

• Total Value Pack — Includes all three protection software suites and the Security and Compliance Suite (the VNX5100 and VNXe3100 exclusively support this package).

VNXe application awareness The VNXe platform features a simplified user interface that is designed for IT generalists rather than for storage specialists. Storage is a key component in the implementation of business-critical applications. Making the deployment and management of storage straightforward while automatically incorporating best practices reduces the time required to set up an environment and reduces costly mistakes.

At the time of publication, application support is provided for:

• Microsoft Exchange



15

• VMware® datastores

Network file system (NFS)

VMware vStorage Virtual Machine File System (VMFS) and Raw Device Mapping (RDM) using iSCSI

• Hyper-V datastores using iSCSI

• Shared folders

Common Internet File System (CIFS) for Windows

NFS for UNIX or Linux

• Generic application storage using iSCSI

When combined with simple wizard-driven installation and storage provisioning, along with EMC’s proven track record for reliability and high availability, the VNXe platform provides a low-cost entry point into the EMC storage family.

Advantages of VNXe platforms This section covers the major advantages of VNXe platforms.

Accessibility The VNXe platform provides consolidated access to stored data from multiple hosts, users, and applications by using existing IP network connectivity and industry-standard protocols, including CIFS, NFS, and iSCSI.

Ease of management A simple-to-use, web-based user interface controls the VNXe platform operations, including tools to manage, monitor, and configure storage and system settings.

High-performance and high-density storage The platform has the ability to store data using high-speed SAS and high-capacity near-line (NL) SAS storage disk drives. These disk drives accommodate most of the organizational and application requirements.

Expandable capacity and flexible upgrades The platform provides SAS and NL-SAS drives to store and protect files, folders, and application data. These drives can be expanded to accommodate a variety of application, host, or organization requirements.

Compliance with application storage best practices The platform has built-in best practices to provision and manage application data such as Microsoft Exchange, Microsoft Windows Hyper-V, VMware, generic iSCSI, and shared folder storage.

Automatic or manual data protection The platform has built-in tools to protect valuable data by using snapshot schedules to create point-in-time images of the data from which data can be restored. Snapshots can be created manually or by using standard snapshot schedules and custom schedules.



16

Security Secure system management is provided through HTTPS communication, manageable system accounts and authentication, and user roles. Secure access to VNXe storage resources is provided through Challenge-Handshake Authentication Protocol (CHAP) for iSCSI storage and compliance with NFS and CIFS access controls for storage resource security.

Antivirus support VNXe supports VEE Common Anti-Virus Agent (CAVA). CAVA is a component of the VNX™ Event Enabler (VEE) 4.5.1, which is part of the Security and Compliance Suite. CAVA provides an antivirus solution to clients using the VNXe platform. CAVA uses third-party antivirus software to identify and eliminate known viruses before they infect files on the VNXe platform.

File-level retention The VNXe File-Level Retention (FLR) feature provides a way to set file-based permissions to limit write access to the files for a specific period of time. FLR can ensure the integrity of data during that period by creating an unalterable set of files and directories. On VNXe, the FLR feature can be enabled for shared folders and VMware NFS data stores. FLR for VNXe is available as part of the Security and Compliance Suite.

VNXe high-availability architecture The EMC VNXe family of storage arrays is designed such that there are no single points of failure. If one hardware or software component fails, the system automatically takes appropriate action to return to a normal operating condition.

Active-active clustering The VNXe platform has two identical storage processors in the hardware chassis. During normal operation, both storage processors are active and serve data. This is an example of an active-active configuration. If one storage processor fails during normal operation, the other storage processor will take over the work assigned to both the storage processors until the failed storage processor is active. Although the data is available to users at all times, this may impact the overall performance of the system.

Note There is a single storage processor variant of the EMC VNXe3100, which will not be able to perform active-active clustering.

No single points of failure The internal hardware of the array is designed such that data is available to users at all times despite a failure.

The external network is similarly protected. The VNXe platforms support Internet SCSI (iSCSI) multipathing and Ethernet link aggregation to protect against network link failures. Design the network architecture for high availability by using multiple switches. However, the design of such a network is outside the scope of this paper.



17

It is highly recommended that the network settings of the storage processors are identical such that in case of a failover, the storage processor that is active can continue to operate.

RAID group hot spares A primary feature of the Redundant Array of Independent Disks (RAID) concept is the ability to automatically rebuild a faulted drive on a spare drive in the array. Drives allocated for this purpose are called hot spares.

Hot spare recommendations Create a hot spare disk for every 30 active drives on the system. Therefore, two hot spares are required for 60 active drives. When active drives are not required, at least one hot spare is required for every type of drive on the system. For example, if there are 14 SAS drives and 12 NL-SAS drives, it is considered a best practice to have one SAS hot spare and one NL-SAS hot spare. Appendix A: Adding a Hot Spare provides the procedure to create hot spares.

Array-based data replication Data replication is the process to create nonactive copies of critical data in a different location for use in case of significant failures such as site-wide disaster.

The VNXe platform provides array-based data replication technologies to create point-in-time copies at scheduled intervals on different storage pools or different storage arrays. This capability is the enhancement from point-in-time snapshots and provides added protection in various failure scenarios.

EMC Replication Manager provides the user interface for the VNXe array-based iSCSI snapshot and replication technology. The operation of the feature is outside of the scope of this document.

VNXe storage pools The VNXe platform does not provision storage by using a traditional model, where users build a RAID group and then build logical disk units in that group. Instead, VNXe platform creates pools of storage. All the members of this pool have similar characteristics. Application-based storage provisioning is possible by using this approach.

Default storage pools Even though the RAID group and the LUN groupings are not exposed to the user, the array is still using those mechanisms behind the scenes to ensure that data is properly protected.



18

Table 1 lists the three default storage pools that are available by default on VNXe platforms and it also describes their characteristics.

Table 1. Default storage pools

Pool name Disk type RAID type Available capacities

High performance SAS RAID 10 (3+3) 300 GB

600 GB

Balanced performance /Capacity

SAS RAID 5 (6+1) – VNXe3300™

RAID 5 (4+1) – VNXe3100

300 GB

600 GB

Capacity pool NL-SAS RAID 6 (4+2) 1 TB

2 TB

Custom storage pools The default storage pools can be augmented with custom, user-defined storage pools. In general, use custom pools for performance-sensitive applications such as SQL because the custom pool mechanism enables precise control on the number of disks used in the pool and prevents other applications from sharing the disks without explicitly provisioning application storage from the custom pool.

Application-based provisioning overview The key difference between VNXe and other storage platforms is its awareness of what applications are using storage and embedding the best practices for those applications into the provisioning and management process.

Figure 1 shows the first page of the Unisphere Management interface.

Figure 1. VNXe management dashboard

The dashboard not only displays the usable capacity of the array in terms of the applications using it, but it also provides wizard-driven mechanisms to create additional application storage using best practices. This guide focuses on provisioning for Microsoft SQL.



19

The provisioning process has three main steps:

1. Create a storage pool (Refer Chapter 3 Physical Storage Allocation on VNXe: Storage Pools)

2. Configure host connectivity(Refer Chapter 4 VNXe Connectivity Configuration)

3. Use the application-provisioning wizard (Refer Chapter 5 SQL Server Storage Provisioning)

4. Connect the host to the provisioned storage (Refer Chapter 6 SQL Server Connectivity Configuration)

The first two steps are independent and can be performed in any order. The third step requires the first two steps to be completed.



20


21

Chapter 2 Microsoft SQL Server Planning on VNXe


Overview of SQL Server ................................................................ 22

Storage for SQL Server ................................................................. 22

Select the VNXe platform .............................................................. 25

Summary ...................................................................... 26

Microsoft SQL Server Planning on VNXe


22

Overview of SQL Server Microsoft SQL Server is a relational database management (RDBMS) server. Many applications use SQL Server to store, retrieve, and manage data. SQL Server architecture and deployment best practices are beyond the scope of this document. This chapter covers SQL Server storage best practices for the EMC VNXe series.

Storage for SQL Server The storage environment for a SQL Server user database consists of at least one database file and a log file. In many SQL Server implementations, there may be multiple databases and log files. The examples in this paper focus on single-file implementations. For a multi-file implementation, users can easily create additional files inside the same storage object.

The database file contains the table data and other information normally associated with data stored in a database. The log file exists to maintain data consistency for write-ahead logging, data recovery, and other operations related to data management. When planning the storage for SQL Server deployments, consider the aggregate requirements for both the data and log areas. For example, if 900 GB is required for a data file and 100 GB is required for a log file, then a total storage space of 1000 GB is required to store both the database and log files.

Storage capacity and performance are the two key aspects of planning storage for SQL Server. Storage capacity indicates the size of the data (in Gigabytes (GB) or Terabytes (TB)) that can be stored. The performance of a database indicates the number of I/O operations that can be accessed by a user per second. One of the most common mistakes made while provisioning SQL Server storage is to consider only the storage capacity of the database. To ensure a high-quality customer experience, EMC recommends users consider the performance requirements (IOPS) before the capacity requirements (GB).

Performance planning for SQL Server To plan the performance requirements, it is important to understand how the application uses the storage. In some cases, you can assume relationships between the amount of data and the number of IOPS, or the number of users and the number of IOPS. SQL Server is an application environment, not a user-facing application. It provides services such as data storage to applications that run on it. For this reason, it is not possible to give a clear definition of what constitutes a ‘SQL workload’ or a ‘SQL user.’ These vary depending on the application that is running in the SQL Server environment.

However, it is possible to broadly define certain types of workloads and their general characteristics.

SQL Server workload The two ends of the SQL Server workload spectrum are generally considered: Online Transaction Processing (OLTP) and Data Warehousing (DW). OLTP workloads tend to have a lot of small, discrete transactions that return very quickly. A common example is a point-of-sale system. It generally works on very tightly defined sets of data rapidly and repeatedly. In contrast, DW workloads tend to have complex queries. DW



23

workloads have a small number of users who access very large sets of data, which may require minutes or hours per query.

For a new application deployment, the application vendor should be able to provide guidance around the number of IOPS the application may require, and if that number varies based on the number of users, the size of the data, or any other part of the environment. For existing applications, this information is available in Windows PerfMon on SQL Server. Table 2 provides the most common PerfMon parameters.

Table 2. PerfMon parameters

PerfMon parameter Usage

Logical Disk\Avg Disk Reads/s Gives the number of read IOPS for the logical disk.

Logical Disk\Avg Disk Writes/s Gives the number of write IOPS for the logical disk.

RAID type selection for performance The EMC VNXe platform uses RAID protection to provide high-performance storage, and to ensure that the physical failure of a single drive does not impact data availability. The VNXe platform can provide different types of RAID protection. Each type of RAID protection has different performance implications.

Three RAID types are available on the VNXe platform.

Table 3. RAID types available on VNXe

RAID type Definition

RAID 10 The data is mirrored across two drives so that if a single drive is lost, its mirror will still contain the data.

RAID 5 A mathematical formula is applied to the data to create a parity that is stored on a different drive. If a drive is lost, the parity information along with the data on the surviving drives can be used to re-create the data on the lost drive.

RAID 6 In RAID 6, similar to RAID 5, a parity calculation is completed. However, in this case, it is calculated with two different formulas and designed so that the data can be rebuilt even if two drives are lost.

Each RAID type has a different impact on the performance of write operations. These RAID types have different implications on the performance. RAID 10 does not require a parity calculation, but the writes must be sent to both sides of the mirror. The parity RAID types (RAID 5 and RAID 6) both require a parity calculation for every write. The old data and the parity information must be read into the array and the new parity must be calculated. All this must be written back to the disk. Read operations are not impacted.



24

Table 4 explains the write performance impacts of the different RAID types.

Table 4. Impact of RAID type on IOPS

RAID Type IOPS impact

RAID 10 Read: No impact

Write: Two writes to the disk for every write request due to mirrors


Write: Two reads from the disk and two writes to the disk for every write request. (Read old data, read parity, write new data, and write parity)


Write: Three reads from the disk and three writes to the disk for every write request. (Read old data, read parity1, read parity2, write new data, write parity1, and write parity2)

The information in the table shows that RAID 10 is the best RAID type in terms of IOPS. However, the RAID type also has an impact on the storage capacity of a set of disks. Chapter 3: Physical Storage Allocation on VNXe: Storage Pools provides more information about the storage impacts of each RAID type.

The number of IOPS that can be serviced by a disk drive is related to how fast the drive spins. The VNXe platform supports drives with the following spin rates. A long-standing rule-of-thumb is that a drive with a given spin rate can service a set average of IOPS.

Drive spin rate Supported IOPS

15,000 RPM 180

10,000 RPM 120

7,200 RPM 80

Note These are approximations for random I/O operations.

These are not maximum performance numbers; they are guidelines for planning.

Capacity planning for SQL Server Multiple files, such as data files and log files require storage capacity in a SQL Server environment. Depending on how the application uses the log file, the storage requirement may be small (1 to 10 percent of the data file size), or large (100 percent of the data file size). The application vendor or an observation of the existing environment should provide guidance for storage capacity planning.

In addition to the storage capacity used by the database, there are other potential users of space related to the database:

• Array-based functions such as snapshots

• Data file backups



25

• Log file backups

VNXe array-based snapshots Array-based snapshots enable you to retain a view of how the data looks at a specific point in time. This can be useful for a wide variety of operations such as backups, compliance, auditing, or reporting. However, snapshots require space. The specific requirements are outlined in Appendix B: iSCSI Snapshot Sizing.

RAID type selection for capacity As noted earlier, the different RAID types also impact the capacity requirements. A parity RAID type requires additional disks to store parity information. In a RAID 5 implementation, one of the disks is fully devoted to parity. In RAID 6, two disks are consumed in this way. RAID 10, while the best choice for performance, requires the highest capacity. Because RAID 10 mirrors data, half of the disks have their entire capacity consumed by the mirrored data. Table 5 explains the impact of the RAID type on the capacity.

Table 5. RAID type impact on capacity

RAID type Capacity impact

RAID 10 Half of the disks are dedicated to mirroring.

RAID 5 One disk spindle dedicated for parity.

RAID 6 Two disk spindles dedicated for parity.

Select the VNXe platform The VNXe family consists of two models, the VNXe3100 and VNXe3300. These two models differ in hardware specifications and maximum support limits. Appendix C: System Comparison and Limits explains the differences between the two models. Because of these differences, one model may be more appropriate in a SQL environment than the other. Refer to “Storage for SQL Server” on page 22 to select the appropriate VNXe platform for your SQL Server deployment.

Because defining users and workloads for SQL Server environments is multi-faceted, it is common to consider benchmark workloads that tightly define certain things like data layout and transactions patterns, and allowthe discussion of database workloads in a context that is more familiar to application users. These are not directly related to a specific application workload.They are representative of broad application categoriesto validate that a configuration is able to provide certain levels of usability.

For the VNXe platform one important benchmark is the TPC-C -like workload. This benchmark attempts to simulate a small OLTP environment similar to a point-of-sale system. To validate the platform in an OLTP environment, a synthetic workload was configured using the Microsoft SQLIO tool. This synthetic workload mimics an industry-standard TPC-C-like workload. Table 6 shows that both VNXe platforms can achieve significant levels of transactional performance.



26

Table 6. Transactional performance of VNXe platforms

OLTP users VNXe3100 (Transactions per second)

VNXe3300 (Transactions per second)

1,000 50 50

3,000 150 150

5,000 250 250

6,000 300 300

7,000 350 350

8,000 400 400

In this test case, both systems were configured for RAID 10 storage because the OLTP benchmark requires a high percentage of write operations. In addition to standard benchmarks, EMC also examined VNXe performance using the SQLIO tool. This tool is commonly used to simulate different I/O patterns when designing a storage configuration. The results are presented in Appendix D: VNXe Performance with SQLIO Tool.

Summary SQL Server is an application environment. Creating a reasonable storage layout is not a simple task. However, by understanding both the IOPS and storage requirements for the SQL Server application, you can provision the appropriate storage resources for your environment.


27

Chapter 3 Physical Storage Allocation on VNXe: Storage Pools

This chapter presents the following topic:

Provisioning overview .................................................................. 28

Physical Storage Allocation on VNXe: Storage Pools


28

Provisioning overview The first step to provision storage to SQL Server is to create a storage pool.

Create custom storage pools To create custom storage pools, complete the following steps:

Note Refer Chapter 2: Microsoft SQL Server Planning on VNXe to identify the appropriate number of disks and RAID type for your SQL environment.

1. Log in to Unisphere as an administrator.

2. In Unisphere, select System > Storage Pools. The Storage Pools window appears.

Figure 2. Open Storage Pools page

3. Click Configure Disks. The Disk Configuration wizard appears.

Figure 3. Opening the Disk Configuration Wizard

4. In the Select Configuration Mode page, select the storage pool configuration

mode:

a. Select Manually create a new pool.

b. Select the appropriate application from the Select application list box.

NOTE Although the Automatically configure pools option allows the implementation of application-specific best practices creating the storage pool manually provides a higher level of control and workload isolation for SQL Server.

5. Click Next. The Specify Pool Name window appears.



29

Figure 4. Select disk configuration mode

The procedure to add disks to an existing pool is covered in Chapter 7: Management of SQL Server on VNXe.

6. Specify a name for the storage pool: a. In the Name field, type a name for the storage pool.

b. In the Description field, optionally enter a description for the storage pool.

Figure 5. Specify Pool name



30

7. Click Next. The Select Storage Type page appears.

8. Select a disk type for the storage pool: a. Select the storage profile identified earlier.

The identified profile should be the one with the highest rating, but that is not always the case.

NOTE NL-SAS drives are not recommended for SQL deployments.

Figure 6. Select storage type

9. Click Next. The Select Amount of Storage window appears.

Note For the following step, it is crucial to understand the balance between database size and snapshots.

10. Select the amount of storage to use for the storage pool: a. Refer to Chapter 2: Microsoft SQL Server Planning on VNXe for

recommended amount of storage.

b. Select the number of disks to use.

Note Separate dropdown lists appear for 300 and 600 gigabyte drives.



31

Figure 7. Select number of disks

Note This option for the profile shows the number of selected disks out of the available disks in the system. In the example shown in Figure 7, the system has 13 disks, which fit the profile that is selected. However, the RAID 10(3+3) protection level can only use groups of six disks. Therefore, there is a provision to use six or 12 disks. For this example, Use 6 of 13 Disks is selected.

11. Click Next. The Summary page appears.

12. Verify the details, and then click Finish.



32


33

Chapter 4 VNXe Connectivity Configuration


Overview ...................................................................... 34

Configure VNXe iSCSI target .......................................................... 34

Configure host entry .................................................................... 38

VNXe Connectivity Configuration


34

Overview This chapter describes how to configure the VNXe for connectivity to the SQL server host. The configuration process requires two independent steps:

• Create iSCSI target: Configure the VNXe storage processor network interface to accept connections from the SQL server host.

• Create host entry: Identify the intended SQL server host to the VNXe.

Configure VNXe iSCSI target The VNXe iSCSI Storage Server is the software component that performs storage management and monitors operations associated with the iSCSI-based storage. To use VNXe iSCSI storage, the system requires at least one iSCSI server to be configured.

VNXe3100 and VNXe3300 can each have up to 12 iSCSI servers per storage processor (SP). The SQL server deployment described in this guide utilizes a single iSCSI server with redundant network paths configured on SP A. Multiple iSCSI servers must be balanced across the SPs for load-balancing.

In addition to the public IP address and its associated DNS alias used for login purposes, two additional IP addresses, their subnet mask, and their VLAN ID (if applicable) are required. EMC recommends that the IP addresses, subnet mask, and VLAN ID be in the same IP subnet as the iSCSI initiator addresses that will be configured on the SQL server host in Chapter 6: SQL Server Connectivity Configuration.

To create an iSCSI server, complete the following steps:


2. Click the Settings tab and click iSCSI Server Settings. The iSCSI Server Settings page appears.

Figure 8. iSCSI Server Settings

3. Click Add iSCSI Server. The iSCSI Server wizard appears.



35

Note The Add iSCSI Server button is available only for administrators.

Figure 9. Add iSCSI Server button

4. Specify the network details for the iSCSI server:

a. Click Show advanced to expose all fields.

b. In the Server Name field, type a name specific to this iSCSI server.

Note Since the server is associated with a specific SP, it may be helpful to use that SP in the name. For example, SQL-spA-1 for the first instance of an iSCSI server for SQL server on storage processor A.

c. In the IP Address field, type the IP address of the iSCSI server.

Note The address entered here is dedicated for iSCSI storage connectivity. Do not use the public (logon) address.

d. In the Subnet Mask field, type the subnet mask.

e. In the Gateway field, type the gateway address.

f. In the Storage Processor list box, select the storage processor for the iSCSI server.

Ensure consideration is given to current and expected processor loads.

g. In the Ethernet Port list box, select the desired port.

h. If VLAN tagging is in use, click the click to edit to expose the entry:

i. Acknowledge the warning popup.

ii. In the VLAN ID field, type the VLAN.

Note The associated VLAN ID for iSCSI server ranges from 0 to 4095. The default value is 0.



36

Figure 10. iSCSI server dialog box

5. Click Next. The Server Summary page appears.

6. Verify the iSCSI Server settings, and click Finish.

Figure 11. Server Summary page

7. Verify that the iSCSI server is created successfully, and click Close.

8. Select the new server, and click Details. The iSCSI Server Details page appears.



37

Figure 12. iSCSI Server Details

9. Click Add network interface (red arrow) to expose the fields to enter secondary network information:

a. In the IP Address field, type a secondary IP address.

b. In the Subnet Mask field, type the subnet mask.

c. Click Show advanced.

d. In the Ethernet Port list box, select an Ethernet port that is different from the one selected in step 4g on page 35.

e. If VLAN tagging is in use, click the click to edit and do the following:

i. Acknowledge the warning popup.

ii. In the VLAN ID field, type the VLAN.

f. Click Apply Changes. The iSCSI Server creation process is complete.

Note No confirmation window will appear after the new interface information is added. Unisphere returns to the iSCSI Server Details window with the new changes as shown in Figure 13.



38

Figure 13. iSCSI Server Details with changes added

Configure host entry In “Configure VNXe iSCSI target” on page 34, an iSCSI server, also known as an iSCSI target, was configured to receive incoming requests from an SQL server.

This section provides steps to identify a SQL server as a valid user, or iSCSI initiator, of the VNXe.

Note The process to configure the SQL server to access the VNXe storage is covered in Chapter 6: SQL Server Connectivity Configuration.

To configure a host on the VNXe platform, perform the following steps:


2. Select Hosts > Hosts.

Figure 14. Selecting the Hosts dialog box

The Hosts window appears.



39

Figure 15. Hosts window

3. Click Create Host. The Specify Name window appears.

Figure 16. Enter name and description

4. Type a name and description for the host configuration:

a. In the Name field, type a name for the host configuration.

b. In the Description field, optionally type a description for the host configuration.

5. Click Next. The Operating System page appears.

6. Specify the host operating system. For SQL server deployments, different versions of Microsoft Windows are available to choose from:

a. In the Operating System list box, select a version of Windows.



40

Figure 17. Select operating system

7. Click Next. The Network Address page appears.

Figure 18. Add network address of host

8. Specify the host network interface:

Note If you are using VLANs to isolate traffic, specify the interface that is visible from the VNXe platform.

a. Select Network Name or IP Address.

b. In the appropriate field, type the network name or IP address.

Note In this example, the public (login) IP is used. The IP identifies the host to the VNXe; dedicated addresses will be configured on the host for actual iSCSI connectivity.

c. Click Next. The iSCSI Access page appears.

9. Specify the iSCSI access details:

a. In the IQN field, type the SQL server host’s IQN. To obtain the IQN, complete the following steps:

i. Log in to the SQL host.

ii. In the Start > Search programs and files field, type iSCSI Initiator.

iii. Click the program to start it. A prompt to start the service will appear on first access.



41

iv. The iSCSI Initiator Properties window appears.

v. Click the Configuration tab.

vi. Copy the IQN from the Initiator Name field.

vii. Paste the IQN into the IQN field.

b. In the CHAP Secret field, type the password (12 to 16) characters if CHAP is configured:

c. In the Confirm CHAP Secret field, re-type the CHAP password.

Note Optional CHAP authentication may require additional infrastructure resources, and is not covered in this guide.

Figure 19. iSCSI Access page





42


43

Chapter 5 SQL Server Storage Provisioning


Create iSCSI storage overview ........................................................ 44

SQL Server Storage Provisioning


44

Create iSCSI storage overview The next step when creating the storage resource is to run the Generic iSCSI wizard to create iSCSI storage for SQL Server. This chapter provides directions to provision storage from the high performance pool (RAID 10 (3+3) pool) created in Chapter 3: Physical Storage Allocation on VNXe: Storage Pools and present it to the SQL Server that was added in Chapter 4: VNXe Connectivity Configuration.

Configure generic iSCSI storage for SQL Server To configure generic iSCSI storage for SQL Server, complete the following steps:


2. Select Storage > Create storage for generic iSCSI. The Generic Storage Wizard appears.

Figure 20. Unisphere Dashboard

3. Click Create.

4. Specify a name and description for this instance:

a. In the Name field, type a name for the SQL storage resource.

b. In the Description field, optionally type a description for the SQL storage resource.



45

Figure 21. Configure storage pool

5. Click Next. The Configure Storage page appears.

6. In the Size field, type the amount of storage to be allotted.

Note If the recommended pool is not the one you set up for the SQL resource, select the correct pool.

The Thin: Enabled option, shown in Figure 21, can be used to provision storage on-demand for the SQL resource. In this mode, the array creates all the proper objects to support the required storage and their full allocated space. However, only a small amount of that space is consumed. The remaining space is available for additional provisioning needs.

This option is recommended for shared file systems and other areas where requests for space and actual usage may not converge for some time. This option is not recommended for SQL Server.



46

Figure 22. Select snapshot protection

7. Click Next. The Configure Protection page appears.

8. Specify the protection options for the storage pool:

Note Optionally configure snapshots for the SQL storage. Snapshots allow the array to maintain a point-in-time view of the storage. This is very useful for various recovery options. The storage sizing specified earlier does not account for snapshots. If snapshots are required in the environment, the storage creation step helps you configure the required space.

• With Configure protection storage, do not configure a snapshot protection schedule to enable snapshot protection, the Configure Protection Storage Size page appears to configure the space reservation.

Note Using the selected option, you are able to schedule snaps at a later point in time. You can immediately configure the protection size for the snapshots. The configured protection size can be increased at a later point intime, but it cannot be decreased.

• With Configure protection storage, protect data using snapshot schedule, the VNXe will create snapshots according to the schedule created. Default Protection keeps the snaps for two days, More protection keeps it for seven days, and Less Protection keeps the snaps for one day.

Note Use the Customize Schedule button to customize the schedule. This provides the flexibility to modify and add rules to set the time and frequency of snaps to be taken, and the duration to preserve the snaps.



47

Figure 23. Configure snapshot schedule

Note Appendix B: iSCSI Snapshot Sizing explains how to configure iSCSI snapshots.

Figure 24. Configure protection size



48

Figure 25. Configure host access

9. Click Next. The Configure Host Access page appears.

Note Click Create New Host if no host is available.

10. In the Access list box, select Virtual Disks and Snapshots to provide host accessfor snapshot protection.

Note Choose the Virtual Disk option if snapshots are not desired.




49

Chapter 6 SQL Server Connectivity Configuration


Set up a Windows host to use VNXe iSCSI storage ............................... 50

Volume configuration .................................................................. 58

SQL Server Connectivity Configuration


50

Set up a Windows host to use VNXe iSCSI storage In Chapter 4: VNXe Connectivity Configuration, an iSCSI server (also known as an iSCSI target) was configured to receive incoming requests for stored data. This chapter describes configuration of the corresponding iSCSI initiator, which connects the SQL host to the target through Ethernet.

The steps in this section have the following dependencies:

1. The SQL host is running Windows Server 2008 R2.

Note The overall procedure is applicable to other versions of Microsoft Windows, however other versions may have different interfaces. The product documentation from Microsoft for iSCSI configuration provides more information.

2. Two network connections on the SQL host (in addition to the public user login connection) are dedicated to iSCSI connectivity.

Note EMC recommends assigning either dedicated gigabit Ethernet NICs or TCP offload adapters (ToE adapters) to handle iSCSI traffic. It is not advisable to share the user-facing network connection for storage traffic.

This procedure assumes the VNXe is configured with two connections, which is the minimum requirement for high availability. However, the VNXe supports 1 to 4 connections.

3. Two IP addresses in the same subnet as the addresses configured on the VNXe iSCSI target in Chapter 4: VNXe Connectivity Configuration.

Note Ideally, the iSCSI connections are on a separate, private network dedicated to storage traffic. By placing storage traffic on its own network that is routed separately from the main network, the overall security of the storage infrastructure increases, and the overall configuration is simpler.

Connect host to VNXe storage To connect the SQL host to VNXe storage configured in Chapter 5: SQL Server Storage Provisioning, complete the following steps:

1. From the Start menu, open iSCSI Initiator. The iSCSI Initiator Properties dialog

box appears.

Note When accessing the iSCSI initiator for the first time, a popup will appear noting that the service must be started. Click Yes to start the service.



51

Figure 26. iSCSI Initiator Properties

2. Click the Discovery tab, and then click Discover Portal. The Discover Target Portal dialog box appears.

3. Specify the target portal information:

a. In the IP address or DNS name field, type one of the IP addresses of the VNXe iSCSI server configured in Chapter 4: VNXe Connectivity Configuration.

Note A popup will appear if the iSCSI initiator is unable to reach its intended target. Although the wizard will add the intended target to the Target portals list, it is recommended that the issue be resolved before continuing. Troubleshooting failed network connections is beyond the scope of this guide.

Figure 27. Discover Target Portal

4. Click OK.

5. On the Discovery tab of the iSCSI Initiator Properties dialog, verify the following information:

a. The Address column displays the address entered for the iSCSI Target in Step 3a.



52

b. The Port column displays 3260.

c. The Adapter and IP Address columns display Default.

Figure 28. iSCSI target added

6. Click the Targets tab, select the VNXe target in the Discovered targets pane and click Connect. The Connect to Target dialog box appears.

Figure 29. Connect to a target

7. Click Advanced. The Advanced Settings dialog appears



53

Figure 30. Connect to Target dialog box

8. Specify the advanced settings for the iSCSI target:

a. In the Local Adapter list box, select Microsoft iSCSI Adapter.

b. In the Initiator IP list box, select the IP address configured for Local Area Connection 2 in “Connect host to VNXe storage” on page 50.

c. In the Target portal IP list box, select one of the two IP addresses configured for the iSCSI server in Chapter 4 VNXe Connectivity Configuration.

Figure 31. Advanced Settings dialog with default values

9. Click OK. The Connect to Target window reappears.



54

10. Click OK to return to the iSCSI Initiator Properties window.

11. Verify that the status of the iSCSI target is Connected.

Configure multiple connections per session To increase storage availability by configuring multiple connections per session, complete the following steps:

1. Open the iSCSI Initiator Properties dialog box from the Start menu, or continue

from Step 5 on page 51.

2. On the Targets tab, select the VNXe target in the Discover targets pane and verify that the status is Connected.

3. Click Properties. The Properties dialog box appears.

Figure 32. iSCSI target

4. Edit the properties of the VNXe iSCSI target:

a. In the Identifier pane, select the session ID.

b. Click MCS. The Multiple Connected Session (MCS) dialog box appears.



55

Figure 33. Multiple Connected Session (MCS) dialog box

5. Click Add. The Add Connection dialog box appears.

Figure 34. Add Connection dialog box

6. Click Advanced. The Advanced Settings dialog box appears.

7. Complete the following steps:

a. In the Initiator IP list box, select the second ISCSI initiator IP, typically bound to Local Area Connection 3.

b. In the Target portal IP list box, select the second IP configured on the iSCSI server in Chapter 4: VNXe Connectivity Configuration.

c. Verify that Data digest, Header digest, and Enable CHAP logon are not selected.



56

Figure 35. MCS add connection Advanced Settings

8. Click OK. The Add Connection dialog box appears.

9. Click Connect to establish the connection and return to the Multiple Connected Session (MCS) dialog. The Multiple Connected Sessions dialog box appears displaying two connections.



57

Figure 36. New connection added

MCS policy may be left as Round Robin.

Note Testing has shown that Round Robin is best in an environment where the network paths are equivalent. If another option is desired, please refer to the Microsoft documentation on the iSCSI Initiator software.

10. Click OK. The Properties dialog box reappears.

11. Click OK. The ISCSI Initiator Properties window reappears.

12. Click OK.



58

Volume configuration After the iSCSI connection with the VNXe target is established, the VNXe storage appears to the Windows host as two or more new, uninitialized disks. This section explains the procedures to create and configure volumes on the new disks, completing the SQL deployment setup.

Create and configure disk volumes The Windows Disk Manager sees the SQL storage provisioned in Chapter 5: SQL Server Storage Provisioning as two or more new, uninitialized disks.

Complete the following steps to prepare the uninitialized disks for use:

1. To verify the number of disks to be formatted, complete the following steps:

a. From the Start menu, select Administrative Tools > Open iSCSI Initiator. The iSCSI Initiator Properties dialog box appears.

b. Click the Targets tab. The list of available targets appears in the Discovered targets area.

c. Click Devices. The Devices dialog box appears.

Figure 37. Devices: iSCSI-connected disks

2. Verify the number of disks and the disk names are correct, and click OK.

3. Click OK to exit the iSCSI Initiator Properties dialog box.

4. On the Windows host, open Server Manager.

5. In the left pane, expand Storage and select Disk Management. The Disk Management window appears.



59

Figure 38. Disk Management

Each new disk displays as Unknown and Offline. Note the correlation of disk names to the names shown in Figure 37.

6. Right-click the first uninitialized disk, and then click Online. Repeat this for all offline disks.

Figure 39. Select Initialize Disk



60

7. After the disks are online, right-click one and select Initialize Disk. The Initialize Disk dialog box appears.

8. To initialize the disks, complete the following steps:

a. Select the disks to initialize.

b. Select MBR (MBR Boot Record).

Figure 40. Initialize Disk dialog box

9. Click OK.

10. Right-click the online raw disk, and then select New Simple Volume. The New Simple Volume Wizard appears.

Figure 41. Create new simple volume



61

11. Click Next. The Specify Volume Size window appears.

Figure 42. Specify Volume Size

12. Verify the simple volume size matches the maximum disk space, and click Next. The Assign Drive Letter or Path window appears.

13. Select a drive letter, and click Next. The Format Partition window appears.

Note NTFS mount can also be used. In this case, mount a local drive to an empty folder on an NTFS volume by using a drive path instead of a drive letter.

Figure 43. Select a drive letter

14. Perform the following steps:

a. Select Format this volume with the following settings.

b. In the File system list box, select NTFS.

c. In the Allocation unit size list box, select 64K.

Note 64K allocations are recommended by Microsoft SQL.



62

d. In the Volume label field, type a name for the volume.

e. Verify Perform a quick format is selected.

Figure 44. Select drive format settings

15. Click Next. The Completing the New Simple Volume Wizard window appears.

16. Verify the details, and click Finish. A new volume is created.

Figure 45. Completing the New Simple Volume Wizard

17. Repeat Steps 7-14 for each new, uninitialized disk.

The storage is prepared for SQL server. Microsoft SQL product documentation provides more information on how to set up SQL on the VNXe storage.


63

Chapter 7 Management of SQL Server on VNXe


Monitor and manage SQL Server environment .................................... 64

Management of SQL Server on VNXe


64

Monitor and manage SQL Server environment This chapter provides information on how to manage the storage resource created in Chapter 5: SQL Server Storage Provisioning. Data in an organization is always growing. When storage is created by using the iSCSI wizard, it is a common practice to overprovision storage to accommodate data growth. However, there is always a possibility that data growth will exceed the planned amount, and the storage resource will reach its maximum capacity. The VNXe array can expand existing deployments for future consumption.

To increase the size of a storage resource, complete the following steps:

1. Expand storage pools.

2. Add more virtual disks to the storage resource.

Expand storage pools To increase the size of a storage resource, either a new storage pool or the existing pool that contains the storage resource can be used. Follow the steps outlined in Chapter 3: Physical Storage Allocation on VNXe: Storage Pools to create a new storage pool.

Consider the available space when using an existing pool. Omit this step if the existing generic iSCSI resource has more available capacity than the amount required for expansion. If the storage pool does not contain sufficient free space, complete the following steps to expand the storage pools.

To expand storage pools, complete the following steps:


2. Select System > Storage Pools. The Storage Pools window appears.

3. Click Configure Disks. The Disk Configuration Wizard appears.



65

Figure 46. Add drives to the existing pool

4. In the Select Configuration Mode page, complete the following steps:

a. Select Manually add disks to an existing pool.

b. In the Select pool list box, select the storage pool where the disks will be added.

5. Click Next. The Select Amount of Storage page appears.

Note On the VNXe platform, groups of drives can be added in multiples of the base RAID group size. For example, if the initial group had six drives, you can add six, 12, or 18 drives to the pool based on drive availability.

Figure 47. Select number of drives to add

6. Select the number of drives to be added to the pool.




66


Extend an existing virtual disks To add virtual disks to an existing deployment, complete the following steps:

1. Navigate to the existing generic iSCSI storage resource that needs to be expanded and click Details. The Generic Storage Details page appears.

Figure 48. Generic storage Details page

2. In the Virtual Disks tab, click Add Virtual Disk. The Virtual Disk Wizard appears.

3. To extend the size of the existing virtual disk, complete the following steps:

a. Select the virtual disk, and then click Details. The Virtual Disk Details page appears.

b. Click the Virtual Disk Capacity tab and modify the current capacity of the disk.

Note The maximum size available to extend the virtual disk depends on the amount of free space in the storage pool where the disk resides. If protection is enabled for the virtual disk, then the size of the extended space is automatically adjusted.

c. Click Apply Changes.

Add virtual disks to existing deployments To add another virtual disk to the storage resource, complete the following steps:

1. Click Add Virtual Disk. The Virtual Disk Wizard appears.

2. Type the name and an optional description of the virtual disk.


4. To configure the storage pool and size for the virtual disk, complete the following steps:

a. Select the pool to create the virtual disk.

Note The new virtual disk must be configured on the same iSCSI server where the iSCSI storage resource that is being expanded resides.

b. Type the protection size (if using data protection features such as snapshots or replication) for the storage resource based on the minimum and recommended protection size.



67


6. Review the details and click Finish.

Extend the storage volume on the host server After extending or adding virtual disks to the iSCSI storage resource, the next step is to extend the storage volume on the host to which the resource is attached.

Extending the size of the existing virtual disk adds unallocated space on the existing virtual disk mapped to the host.

The addition of a new virtual disk shows up as a new disk with unallocated space within the Disk management interface.

Adjust partition boundary To adjust the partition boundary and expand the file system, complete the following steps:

1. In Disk Management, right-click the volume to be extended, and then select Extend Volume. The Extend Volume Wizard appears.

Figure 49. Extend an existing volume

Note The Extend Volume Wizard shows the existing device properties and additional capacity of the iSCSI LUN that can be extended.

2. Click Next. The Select Disks page appears.

3. Select the required disks.

4. In the Select the amount of space in MB box, type or select the amount of space to add to the volume.



68

Figure 50. Extend Volume Wizard

5. Click Next. Verify the volume is extended.

Note Extending the current volume onto allocated space on the same disk keeps the disk in basic format, while extending the current volume onto unallocated space from another virtual disk creates a dynamic disk. The Microsoft article on Basic and Dynamic disks provides more information on basic and dynamic disks.


69

Chapter 8 Replicating SQL Server Data Using VNXe


Protection technologies ............................................................... 70

Configure data protection ............................................................. 73

SQL Server disaster recovery ......................................................... 93

Data protection and SQL Server performance ..................................... 95

Replicating SQL Server Data Using VNXe


70

Protection technologies One way to protect SQL data is to use snapshot and replication features. This chapter explains what these features are and how to configure replication for a production SQL Server environment on the VNXe series.

Snapshots A snapshot is a virtual point-in-time image of the data within a storage resource that has changed since the last snapshot. Snapshots provide a record of the content in the targeted storage resource at a particular date and time, but are not mirror copies of the data. Periodically creating snapshots of file systems and virtual devices is an effective technique to meet data protection and recovery requirements.

Note VNXe snapshots are not a substitute for storage backup operations. Snapshots are not intended to provide resources for disaster recovery or from loss of physical equipment.

Replication Storage replication is a process in which storage data is duplicated either locally or to a remote network device. Storage replication provides an enhanced level of redundancy in case the main storage backup system fails. Replication minimizes the downtime-associated costs of a system failure and simplifies the disaster recovery process.

Replication produces a read-only, point-in-time copy of the source storage data and periodically updates the copy, keeping it consistent with the source data. These point-in-time copies of data are produced through snapshots.

Replication process After a snapshot of the production environment or storage is taken, copy the snapshot to the destination array where an initial full copy occurs. When a new snapshot is taken, it is compared to the previous snapshot and only the data that has changed since the previous snapshot is copied to the destination array. This replication process can be setup locally on a single array or remotely on another array.



71

Figure 51. Replication process

Local data protection Local replication can be used for content distribution, backup, and application testing. Local replication occurs on the same VNXe system. After communication is established, a local replication session can be set up to produce a read-only copy of the source object in a different location on the same VNXe cabinet.

Remote data protection Remote replication can be used for content distribution, backup, application testing, and to fail over to the remote site if the primary site is unavailable. The replication occurs between a local VNXe storage server and a storage server on a remote VNXe or VNX or Celerra. To configure replication to a remote system, both the local and remote systems must be configured to communicate with one another by using a common passphrase. A passphrase is not required if both the local and remote systems are VNXe arrays.

After the communication between local and remote systems is established, set up a remote replication session to create and periodically update a source object at a remote site. After the initial copy, any changes to the local source object are transferred to the remote destination object over the IP network. These transfers are automatic and are based on definable replication session properties.



72

Consistency Consistency is the idea that some applications store critical information in more than one place. For the application to function properly, the data in each location must match or be consistent. If the data is in a consistent state, then the application can restart in the event of a failure, and come online without manual intervention. If the application data is in an inconsistent state, the application typically cannot come online automatically.

Database applications ensure consistency by not acknowledging any write until it has been successfully written to the logs. Thus, when the system recovers from a failure when the logs and the database are inconsistent, the logs are replayed on the database to restore consistency.

There are several types of consistency that dictate different recovery mechanisms and potentially different amounts of time.

Crash consistency Data is considered crash-consistent if it will remain the same as it was before a power failure or a system outage of any kind. Because data is stored on the disk, reverting back to a specific point in time through a recovery process and resuming normal operation from that point is possible. A system ensures crash consistency by writing an I/O to disk before it commits to the application. In a scenario where there is an outage midway between the start and completion of an I/O, no data is written to disk and no acknowledgement is received by the application. When the system is up again, the data is still consistent.

Application consistency If an application can resume normal operation from an older point-in-time copy or an image of itself without the need for any recovery calculation or process, the copy or image is said to be application consistent. Snapshots taken through EMC Replication Manager ensure application consistency. SQL Server writes all new data to the user data log. After the data is committed to the log, it is written to the user database. The user database resides on the disk and the database pages that are in active use also reside in memory. SQL Server uses a lazy writer mechanism to improve I/O performance. Replication Manager freezes new writes and flushes dirty or unwritten transactions and database pages to the disk. The snapshot is then fractured and the database is thawed, returning to normal operation. This process ensures an application-consistent state, and allows the snapshot to be mounted and immediately attached without having to resort to SQL Server recovery.

Data protection for Microsoft SQL Server SQL data is essential to the smooth functioning of an organization and must be protected to ensure fast and timely recovery from site failures, planned or unplanned outages, and data corruption. SQL data on VNXe is protected by means of iSCSI replication enabled by using EMC Replication Manager.

VNXe snapshot protection provides the capability to take point-in-time consistent copies of SQL databases and revert to it in case of any data corruption. These point- in-time copies can also be utilized separately for test or backup purposes as deemed necessary in an organization.



73

With the help of VNXe local replication, consistent copies of SQL databases can be copied and periodically updated on the same VNXe. In case of any data corruption, the SQL database can be re-created by restoring the databases. Local replication also creates a point-in-time copy of the most recent copy, which can be used for other business-specific operations.

With VNXe remote replication, consistent copies of SQL databases can be copied and periodically updated to a remote VNX or VNXe or Celerra. If there is any data corruption, server failures or even complete failure of the production site, the SQL databases can be re-created by restoring the databases. Remote replication also creates a point-in-time copy of the most recent copy, which can be used for other business-specific operations.

Replication Manager EMC Replication Manager manages EMC point-in-time replication technologies and coordinates the entire data replication process from discovery and configuration to the management of multiple disk-based replicas. It allows rapid recovery of the data on a volume to any point in time (crash-consistent recovery) or to a significant point in time (application-consistent recovery). Replication Manager allows grouping multiple LUNs as a single entity for snapshot and replication. This ensures the application is snapped and replicated in a consistent manner.

Replication Manager provides a graphical user interface to manage replication and snapshots of iSCSI LUNs. It controls the creation of snapshots, marks the snapshots for replication, and initiates the copy job from the source to the destination. During a snapshot or replication job, Replication Manager ensures that applications are in a consistent state by quiescing data reads and writes, including flushing the cache.

Configure data protection This section describes how to configure and use Replication Manager with VNXe storage arrays to protect SQL data through replication. This document describes how to configure and replicate data between two VNXe arrays. Configuring replication on the same VNXe array is set up with the same procedure, but with some differences. These differences are explicitly mentioned in the following steps.

This section also provides information on how replicas can be used for testing, backup, or disaster recovery scenarios.

The main steps involved in the replication process are:

1. Prepare the environment for replication: Complete the following steps only once to configure replication.

a. Establish replication trust between the arrays. This step must be performed in Unisphere. This step is not required to replicate data on the same array.

b. Install and configure Replication Manager for replication in both production and remote arrays.



74

2. Create and use replicas: Complete the following steps for every storage resource that is being replicated:

a. Create destination storage

b. Create an application set

c. Create replication jobs

3. Run and manage replication: Complete the following steps to initiate the replication process and to use the replicas created through Replication Manager. These steps can be performed any number of times depending on the business needs.

a. Use Replication Manager to start replication

b. Use Replication Manager replicas

Establish replication trust To establish a connection between two storage platforms, complete the following steps:

1. In Unisphere, click the Hosts tab and then click Replication Connections. The

Replication Connections page appears.

2. Click Add Replication Connection. The Add Replication Connection Wizard appears.

Figure 52. Replication Connections page

3. Specify the remote system details:

a. In the System Type list box, select VNXe.

Note Replication can be configured between a VNXe and a Celerra or VNX. This configuration is beyond the scope of this document.

b. Select and type the network name or IP address of the remote VNXe.

c. In the User Name field, type the username for the Unisphere Management UI of the remote VNXe.

d. In the Password field, type the password to the Unisphere Management UI of the remote VNXe.



75

e. In the Confirm Password field, type the password again.

Figure 53. Add Replication Connection Wizard


5. Review the details and click Finish. The results of the operation are displayed.

If the operation fails in any of the steps due to any reason, failure details such as error code and error details are displayed.

6. If the storage is configured on public and private IP addresses, specify the interfaces to be used for replication. To do that, complete the following steps:

a. From the Replication Connections menu, select the destination system and click Modify. The Modify Replication Connection page appears.

b. In the SP A list box, select the interface for replication on SP A.

c. In the SP B list box, select the interface for replication on SP B.

7. Click OK.

Note Perform step 6 on the second VNXe as well. Ensure that each selected interface on both VNXe systems is routable from the other selected interfaces. To confirm the interfaces are routable, navigate to Settings > More Configuration > Routing Configuration to ping a particular destination IP from a specific interface.

Create replication destination storage The replication destination can reside on the local or remote storage platform based on the replication type (remote or local). The steps to create a destination storage are the same for both types of replications (remote and local). It is assumed that the remote storage system is also a VNXe array. Replication to other EMC storage systems such as VNX and Celerra is not in the scope of this document.

To create the replication destination storage from the Generic iSCSI Storage wizard, complete the following steps:

1. In Unisphere, click the Storage tab, and then click Generic iSCSI Storage.



76

2. Click Create a Replication Destination. The Generic Storage Wizard appears.

Figure 54. Generic iSCSI Storage page


a. In the Name field, type a name for the destination storage.

b. In the Description field, type a description for the destination storage.

Note The Description field is optional.

Figure 55. Specify Name



a. Select the pool on which the generic iSCSI storage will be created.

b. In the Size field, type the size of the storage.

Note The size of the destination generic iSCSI storage should be the same as the source generic iSCSI storage that was created in Chapter 5: SQL Server Storage Provisioning. The size can be viewed in the Details page of the source generic iSCSI storage resource that is being replicated.



77

Figure 56. Configure Storage page

6. Click Next. The Configure Protection page appears.

7. Select Configure protection storage, do not configure a snapshot protection schedule.

Note EMC Replication Manager that will be used to manage SQL replication has its own snapshot schedule feature. So, the Configure protection storage, protect data using snapshot schedule option must not be selected.

Figure 57. Configure protection page

8. Click Next. The Configure Protection Storage Size page appears.

9. Configure the amount of storage reserved for protection as configured on the source iSCSI storage.



78

Note Appendix B: iSCSI Snapshot Sizing provides more information on the space required by snapshots and how to determine an appropriate protection size.

Figure 58. Configure protection storage size page

10. Click Next. The Configure Host Access page appears with the list of currently configured hosts.

11. In the Access list box, select Virtual Disk and Snapshot for the particular host to provide host access for the mount operation. The Virtual Disk and Snapshot option provides access to all virtual disks and all promoted snapshots.

Note The host access for the virtual disk and snapshot is given to the server where the replica of the SQL Server storage will be mounted after the iSCSI copy is done. The replica must be mounted on a server to check the database consistency of the destination replica.

Figure 59. Configure host access



79

Note For hosts running Windows 2008 (or later), use the quick-format option when formatting iSCSI storage resources, VMFS datastores, or Hyper-V datastores. If the full format option from Windows 2008 hosts is used and snapshot protection for the storage is enabled, then more protection storage for the storage resource must be enabled than the primary storage. If this is not done, then the snapshot operations will fail, returning an error that the protection resource is full.


13. Verify the details and then click Finish. The read-only logical disk is created as the replication destination.

Note This step must be repeated for every iSCSI storage resource that is used by the databases. For example, if you created separate storage resources for database and log files, then another replication destination of the same size as the storage resource for logs will have to be created.

Install and configure Replication Manager This section covers the procedure to install and configure Replication Manager, and set it up for replication.

Install Replication Manager server and agents The prerequisites to install Replication Manager server and agents are:

• Replication Manager server must be installed on a dedicated host to manage all replication jobs.

• The Replication Manager Administration console can be installed on any host that can access the Replication Manager server.

• Replication Manager agents must be installed on all the hosts that are currently accessing or will be accessing the storage resources in the future. To replicate SQL databases, the SQL Server agent must be installed on the host running SQL Server. Similarly, the SQL Server agent must be installed on the SQL server host at the disaster recovery site.

Note Note the port number that will be used to communicate with the Replication Manager server because that port number will be required to add the host to the Replication Manager console.

The Replication Manager Administrators Guide available on EMC Powerlink® provides more information on installing Replication Manager.

Attach hosts to Replication Manager To attach hosts to Replication Manager, complete the following steps:

1. Start the Replication Manager console from the host on which Replication Manager Server is installed.

2. Add all hosts running the Replication Manager agents to identify the applications running on the hosts.

3. In EMC Replication Manager, right-click Hosts, and then select New Host. The Register New Host dialog box appears.



80

Figure 60. Adding Hosts


a. In the Host Name field, type the name of the host.

For SQL data replication, this will be SQL Server that holds the databases.

b. In the Port field, type the port number.

The port number should be the number that was used when installing the Replication Manager agent on the host.

c. Click OK.

Create an application set After successfully registering the hosts, create an application set. An application set maps and contains the data to be replicated.

To create an application set, complete the following details:

1. In EMC Replication Manager, right-click Application Sets on the left pane, and then select New Application Set. The Application Set Wizard page appears.



81

Figure 61. Create an application set

2. Click Next. The Application Set Name and Objects page appears.


a. In the Name field, type a unique name for the application set.

Note For SQL, Replication Manager detects the SQL Server and all the associated databases.

b. Select the SQL server host that holds the databases. The Application Credentials dialog box appears to prompt for credentials to access the SQL server.

c. Type the credentials and click OK.

Figure 62. Application Credentials

4. After verifying the credentials, all databases attached to the SQL Server are displayed. Select the databases you want to replicate.



82

Figure 63. Application Set Name and Objects page

5. Click Next. The Completing the Application Set Wizard page appears.

6. Specify the required settings for the application set:

a. Click Run Validation to validate the application set. The Validation dialog box appears.

To validate an application set, Replication Manager checks for potential problems such as invalid or missing database configuration files, invalid database settings, or incorrect agent configuration.

b. When the validation is complete, click Close.

c. Select Create a job for this application set. This opens the Job Wizard automatically on closing the Application Set Wizard. Jobs can also be created by navigating to the left pane of Replication Manager Console and right clicking the job icon and selecting New Job.

d. Click Finish. The application set is created and the Job creation page appears.

Note Alternatively, you can right-click Jobs from the left pane in Replication Manager, and then select New Job.



83

Figure 64. Completing the Application Set Wizard page

Create a replication job To create a replication job, complete the following steps:

1. In the Job Wizard, select the application set to replicate and click Next. The Job Name and Settings page appears.

Figure 65. Job Wizard

2. Specify the name of the job and select replication options:

a. In the Job Name field, type a unique name for the job.

b. In the Replication Source list box, select Primary Storage.

c. In the Replication Technology list box, select the replication technology based on the replication type:



84

i. Select Celerra SnapSure™ for snapshot protection.

ii. Select Celerra Replicator™ for remote replication.

Because this chapter deals with remote replication between two VNXe platforms, select Celerra Replicator.

d. Specify the replica lifetime by number or by duration:

i. Select Limit replica count to: <number> to modify a replica rotation to delete replicas based on the maximum number of replicas.

ii. Select Keep replica for to specify the retention period on replicas.

Figure 66. Job Name and Settings page

3. Click Next. The Target replication storage page appears.

4. Specify the storage to be used for the replica:

a. From the Storage System Hostname list box, select the destination storage system.

b. From the iSCSI Server IP address list box, select the IP address of the destination system that is used for replicating the data.

c. From the iSCSI Server IQN (Optional) list box, select the IQN of the destination storage on the remote system.

Note To view the IQN of the destination generic iSCSI storage, click the Storage tab and click Generic iSCSI Storage. Select the destination iSCSI storage and click Details.



85

Figure 67. Target replication storage page

5. Click Next. The Mount Options page appears.

6. Select the replica mount host, path (if required), and other mount options.

Figure 68. Mount Options

7. Click Next. The Starting the Job page appears.

A Replication Manager job can be invoked in three ways:



86

• Start the job manually or by using a third-party scheduler. The Replication Manager Product Guide available on Powerlink provides more information on third-party scheduler.

• Create a schedule. If Schedule the job is selected, the Add Schedule dialog box appears. Enter the required details to define the schedule as shown in Figure 69.

Note Give a gap of at least 15 minutes between each snapshot to ensure that each snapshot completes successfully.

• Start the job after another job completes. The job selected can be associated with the same application set or with another application set.

8. Select the appropriate option according to business requirements.

Figure 69. Starting the Job page with schedule

9. Click Next. The Users to be Notified page appears.

10. Type the email addresses of users who need to be notified by email when the job completes.

Note The Replication Manager Product Guide provides more information on email notifications.



87

Figure 70. Users to be notified

11. Click Next. The Completing the Job Wizard page appears.

12. Review the details and click Finish.

Run a replication job through Replication Manager To run a job, complete the following steps:

1. Click Jobs in the Replication Manager left navigation pane. The jobs created are listed in the right pane.

2. Right-click the new job, and then select Run.

When the replication job is run for the first time, all data from the production LUN is copied to the destination LUN. This first run may consume more time depending upon the amount of data that must be copied. All subsequent runs will only copy the data that has changed on the source LUN and will take lesser time.

Figure 71. Run a replication job

As part of the replication process, Replication Manager creates snapshots of the source and destination datastores. To view the snapshot, click the Snapshots tab of



88

the source/destination storage details. The Taken By column shows Replication Manager.

Figure 72. View Replication Manager Snapshots

Replication Manager replicas A replica is a clone or a snapshot. Replication Manager creates a clone of the production iSCSI resource on the destination replicas created by Replication Manager and can be mounted to any host and used for backup or test environments.

If the source becomes unavailable due to natural or human-related disasters, the production storage can fail over to the clone on the destination storage. The destination LUN becomes read/write, and any host with proper access can use it.

Mount a Replication Manager replica When a replica (snapshot) is mounted to a particular host, that host gets read and write access to it. To mount a particular replica, complete the following steps:

1. In EMC Replication Manager, select the application set from the left pane. The replicas associated for the application set are visible in the right pane.

2. Right-click the replica, and then select Mount. The Mount Wizard page appears.

Figure 73. Mount a replica



89

3. Select the destination host and path to mount the replica.

Note To unmount the mounted replica, right-click the replica in Replication Manager, and select Unmount. The changes made to the replica will be discarded and the server on which the replica is mounted no longer has access to the snap.

Restore a replica In the event of database corruption, a replica can be restored to revert the application to a particular point in time. With the help of the restore option, you can restore all or specific data from a replica taken at a particular point in time.

To restore from a replica, complete the following steps:

1. Right-click anywhere within the application set window and select restore a replica. The Restore Wizard appears.

2. Select the replica you want to restore.

Figure 74. Restore Wizard

3. Click Next. The Objects to be Restored page appears.

4. Select the objects to restore from the replica.



90

Figure 75. Objects to be Restored page

5. Click Next. The Restore options page appears.

6. Provide the restore option: These are application activities that will be performed before or after the restore. These activities can be initiated on the entire SQL Server instance or can be initiated on an individual database level.

a. Select Backup the transaction logs before restoring to initiate the backup of SQL Server transaction logs before the restore operation.

b. Select the appropriate recovery option:

− No Recovery — instructs the restore operation not to roll back any uncommitted transactions when in no recover mode. The database is unusable in this intermediate and nonrecovered state. The Database Administrator can manually apply database transaction log backups.

− Recovery — instructs the restore operation to roll back any uncommitted transactions. After the recovery process, the database is ready for use.

− Standby — Restores files and opens the database in read-only mode. Subsequently, the Database Administrator can manually apply transaction log backups.

c. Select the Replace restore option, if applicable. This option causes SQL Server to skip certain important safety checks that the restore procedure normally performs. Because these checks are not performed, this option should only be used by an experienced Database Administrator.



91

Figure 76. Restore Options

Replication failover Replication failover enables the user to fail over an iSCSI clone replica to a dedicated disaster recovery server from the production server. When an iSCSI clone replica is failed over, it is made available for disaster recovery. A failover also makes the production storage read only if it is accessible.

To fail over a clone replica, complete the following steps:

1. Right-click the clone replica and select Failover. The Failover dialog box appears.

Figure 77. Replication Failover

2. Select the name of the alternate production host on which to promote the Celerra Replicator clone replica.

3. Select one of the failover options:

Edit job properties after failover — Enables the user to edit the replica's job properties after a failover successfully completes. This option is useful if



92

the user plans to run for a period of time on the dedicated disaster recovery VNXe array before failing back to the normal production array. Depending on the Celerra Replicator job configuration, the Storage, Mount, and Startup tabs may require modification after the failover has completed.

Don't fail if drive(s) already mounted (failback scenario) — Under normal circumstances, an attempt to mount a replica on a drive that is currently in use will fail. This option overrides that behavior, and informs Replication Manager that the replica already exists on this particular disaster recovery site, and the drives are still assigned. When this option is enabled, Replication Manager will not fail the mount operation when attempting to mount the drive.

Figure 78. Failover dialog box

Promote a clone to production The Promote Replica dialog box enables the user to promote iSCSI replication storage to an alternate host. When you promote a Celerra Replicator clone replica, it is made available for repurposing on another production host, or for testing disaster recovery procedures without disrupting the production environment.

To promote a replica, complete the following steps:

1. In Replication Manager, right-click the replica and select Promote to Production. The Promote Replica dialog box appears.

2. In the New proxy or production host list box, select the name of the alternate production host on which to promote the Celerra Replicator clone replica.

Note The drive letters used on the original production host must be available on the new production host because the replica promotion will mount the clone LUNs to the same drive letters.

3. In the New application set name field, type a new application set name for the Celerra Replicator clone replica. This application set is created to protect the promoted data.



93

Figure 79. Promote Replica dialog box

4. Click Options to change the following option:

Automatically create jobs for the new application set — makes a copy of all local snap jobs of the source application set and copies them to the new destination application set. If there are no local snap jobs defined for the source application set, a general local snap job with no options is created. After the replication storage is promoted to the alternate production host, the local snap job in the new application set can protect the data.

SQL Server disaster recovery The production environment may become unavailable Due to a disaster. This section describes how to bring a SQL Server online at a disaster recovery site from replicated copies of databases which could be on a remote VNXe or the same local VNXe.

Note This section assumes that a separate SQL Server architecture similar to the production site exists at the remote location.

Remote SQL Server and database The first step required to bring the remote site online is to give the remote SQL Server access to the databases. To do this, the clone replica from Replication Manager must be failed over and presented to the remote SQL Server.

“Replication failover” on page 91 provides instructions on how to failover a replica clone.

Attach the database After the remote SQL Server has been given access to the clone replica that contains the databases, complete the following steps:

1. Attach the databases to the SQL server.

2. To check the consistency of the database, run a database check as shown in Figure 80.



94

Figure 80. Run a database check in SQL Server

Fail back to production site

If the production site is brought back online and user traffic needs to be restored to the production site, complete the following steps:

1. Replication job settings need to be changed to point to the original source storage resource as the destination.

2. Run the replication job again to copy only the changes that have been made on the remote site storage resource.

3. After the copy is completed, fail over the production replica to the production SQL Server.

This step will again make the destination storage resource read only and the production storage read-write. The job properties need to be changed to its original settings to continue protection through replication.

Promote to production instead of failover The remote SQL Server can also be given access to the destination replica clone by promoting the replica to production. To bring the database up at the remote site the same steps as mentioned for a failover would follow. However, a failback to the original source would not be possible. In a disaster scenario, if a replica is promoted to production instead of a failover, then a new application set and replication jobs must be created to protect the remote SQL Server storage that point onwards. The old production storage resource is not usable as a failback replication destination. A new empty storage resource and an initial full-copy to that new resource are required for replication protection.



95

Data protection and SQL Server performance Replication and snapshot technologies have minimal impact on SQL Server performance because these features increase the load mainly on the storage array.



96


97

Appendix A Adding a Hot Spare

This appendix presents the following topic:

Add a hot spare ...................................................................... 98

Adding a Hot Spare


98

Add a hot spare A spare disk is a designated storage disk that is used to replace a failed or faulted device in a storage pool. The spare disk is not used to actively store data, but it can be used to automatically replace a failed disk if a disk failure occurs.

To add a new spare drive to the hot spare pool, complete the following steps:


2. Select System > Storage Pools. The Storage Pools page appears.

3. Click Configure Disks. The Disk Configuration Wizard appears.

Figure 81. Storage Pools page

4. Select the disk configuration mode:

a. Select Manually add disks to an existing pool.

b. In the Select pool list box, select Hot Spare Pool.

Adding a Hot Spare


99

Figure 82. Select Configuration Mode page

5. Click Next. The Configure Spares page appears.

6. Select the number of hot spares to configure from each list box. The recommended number of hot spares is indicated with an asterisk.

Figure 83. Configure Spares page


8. Click Finish. The Results page appears.

Adding a Hot Spare


100

Figure 84. Summary page

9. Click Close. The Storage Pools page appears.

Figure 85. Results page


101

Appendix B iSCSI Snapshot Sizing

This appendix presents the following topic:

Snapshot overview ..................................................................... 102

Calculate space requirements ........................................................ 102

iSCSI Snapshot Sizing


102

Snapshot overview A snapshot is a point-in-time view of the iSCSI LUN. When you create a snapshot, all the space that is currently used by the LUN is assigned to the snapshot. Subsequently, write operations cause additional blocks to be allocated for the new data, preserving the point-in-time view of the snapshot. The amount of storage pool space occupied by the iSCSI LUN and snapshot depends on how much data has been changed because the oldest snapshot was taken.

It is difficult to determine the space required for a snapshot. The provisioning wizard on the VNXe platform recommends a reasonable protection size, which is appropriate in a wide variety of situations. However, for better control of space utilization, you can override the recommended settings.

Calculate space requirements Consider the following aspects to calculate the space required in a pool:

1. The size of the LUN. If a 100 GB LUN is required, the minimum pool size starts at 100 GB.

2. For the first snapshot, provision enough space to ensure that the system stays stable and the data is protected even in a worst-case scenario, for instance if every single block of data in the LUN is changed while the snapshots are active. Therefore, the pool requirement is doubled, that is, 200 GB.

3. Enough space is required to accommodate subsequent snapshots, each with a variable amount of changed data. If snapshots are created every day for a week and about 10 percent of the data is expected to change, then the pool requirement is 270 GB (after adding the extra 10 percent multiplied by 7).

4. Snapshots may be used at some point in time. If read-only access is required to the snapshot, then no additional space is required. However, to get write access to the snapshot, an additional amount of space that is proportional to the amount of data change is required. Therefore, if 1 percent of the data will change in the writeable copy, the required space for the pool is 271 GB for a 100 GB LUN.



103

A single snapshot presents the largest cost in terms of space reservation. As the number of snapshots grows, the amount of storage required changes by the data change rate for that snapshot.

Note The VNXe platform uses the same underlying technology as the EMC Celerra® product family. Sizing Considerations for iSCSI Replication on EMC Celerra — Technical Note provides a complete discussion of sizing considerations in a wide variety of use cases available on Powerlink.

The sizing information presented in this section is only applicable to iSCSI LUNs. The shared folder snapshots on the VNXe platform use a different set of technologies that have different sizing requirements.



104


105

Appendix C System Comparison and Limits

This appendix presents the following topics:

Model components and limits........................................................ 106

Software configuration limits ......................................................... 106

System Comparison and Limits


106

Model components and limits The VNXe3100 and VNXe3300 models in the VNXe family consist of the same core software. However, the two models have very different hardware.

Table 7 compares VNXe3100 and VNXe3300.

Table 7. VNXe model components and limits

Component VNXe3100 VNXe3300

CPU Intel Jasper dual-core 1.73 GHz with Hyper-Threading

Intel Westmere quad-core 2.13 GHz

System memory (per storage processor)

4 GB 12 GB

Number of memory channels

2 3

Memory speed 1066 MHz 1066 MHz

Connectivity options 12 x 1 GbE • 16 x 1 GbE

• 8 x 1 GbE and 4x 10 GbE

Max number of disks • 96 (dual SP)

• 48 (single SP)

120

Allowed drive types • 300 GB 15k SAS

• 600 GB 15k SAS

• 2 TB NL-SAS

• 1 TB NL-SAS

• 300 GB 15k SAS

• 600 GB 15k SAS

• 2 TB NL-SAS

• 1 TB NL-SAS

Software configuration limits Table 8 describes the VNXe operating system limits.

Table 8. Software configuration limits

Parameter Limit

Hosts connected 500

Snapshots per virtual disk 2,000

Virtual disks 256

Snapshots per shared folder 96

Shared folders 500

Maximum virtual disk size 1.999 TB

Maximum shared folder size 15.533 TB



107

Parameter Limit

Open files 200,000

Concurrent connections 20,000



108


109

Appendix D VNXe Performance with SQLIO Tool

This appendix presents the following topics:

Storage performance overview ....................................................... 110

SQLIO and simulated workload ...................................................... 110

VNXe Performance with SQLIO Tool


110

Storage performance overview Storage sizing for SQL Server is important for a successful deployment. For optimum performance, the storage system must be properly sized for current and future SQL Server workloads. A better understanding of the application workload is necessary to properly size the SQL Server storage to achieve the required performance. Application workloads vary in I/O size, number of reads and writes, IOPS (or throughputs), and the nature of the data access (random or sequential).

SQLIO and simulated workload It is difficult to define a SQL Server workload or a SQL user because they are application-dependent. The majority of small to medium businesses typically use SQL Server with transaction-oriented applications like point of sale systems. The transaction-oriented application workload is dominated by 8K I/O size on the disk since the SQL Server page size is 8K. The workload has very random data access.

The SQLIO tool was run with a simulated 8K I/O size workload with random data access. The simulation was executed on both VNXe platforms, on both RAID 5 and RAID 10 configurations. The workload increased until the disk latency reached close to 20 ms for each scenario. Table 9 shows the maximum IOPS for each configuration:

Table 9. SQLIO performance for 8K random I/O in IOPS

I/O type VNXe3100 VNXe3300

(3+3) RAID 10 (4+1) RAID 5 (3+3) RAID 10 (6+1) RAID 5

Read 2,000 1,200 3,000 1,500 Write 2,000 600 3,000 1,000

• VNXe3300 performed better than VNXe3100 because of its larger storage cache and faster processors.

• RAID 10 performed better than RAID 5 in write operations due to RAID impact. Chapter 2: Microsoft SQL Server Planning on VNXe provides more information about RAID impact.

• The number of reads is equal to, or better than the number of writes because reads do not have a RAID penalty.

The SQLIO results show IOPS for read and write operations only. A typical SQL Server environment has a mixture of read and write operations. To size a SQL environment, make sure the workload throughput is between the read and write throughput listed in Table 9.

The results from Table 9 are executed on one set of RAID groups, and therefore should not be considered as the theoretical maximum throughput for the VNXe platforms.

Microsoft SQL Server 2008 on EMC VNXe · PDF fileMicrosoft SQL Server 2008 on EMC VNXe Series...

Documents

Transcript of Microsoft SQL Server 2008 on EMC VNXe · PDF fileMicrosoft SQL Server 2008 on EMC VNXe Series...