EMC Business Continuity for Microsoft Exchange 2010 Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups

EMC Business Continuity for Microsoft Exchange 2010 Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups A Detailed Review EMC ...
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EMC Business Continuity for Microsoft Exchange 2010 Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups A Detailed Review

EMC Information Infrastructure Solutions Abstract

This white paper documents the performance validation of Microsoft Exchange Server 2010 on an EMC® Iomega® StorCenter ix12-300r Network Storage Array. By utilizing Serial Advanced Technology Attachment (SATA) drives with native Exchange Server 2010 database availability group (DAG) protection, this solution provides a no-backup and a no-RAID option for customers in small- to medium-sized business environments. November 2010

Copyright © 2010 EMC Corporation. All rights reserved. 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. For the most up-to-date listing of EMC product names, see EMC Corporation Trademarks on EMC.com All other trademarks used herein are the property of their respective owners. Part number: H8035

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 2

Table of Contents Executive summary ........................................................................................................................... 5 Business case ............................................................................................................................... 5 Product solution............................................................................................................................. 5 Key results..................................................................................................................................... 5 Introduction ....................................................................................................................................... 6 Purpose ......................................................................................................................................... 6 Scope ............................................................................................................................................ 6 Audience ....................................................................................................................................... 6 Terminology................................................................................................................................... 6 Technology overview ........................................................................................................................ 8 Introduction to the key components .............................................................................................. 8 Microsoft Exchange Server 2010 .................................................................................................. 8 Microsoft Hyper-V 2008 R2 ........................................................................................................... 8 Iomega StorCenter ix12-300r Network Storage Array .................................................................. 8 Environment .................................................................................................................................... 10 Physical environment .................................................................................................................. 10 Targeted customer profile ........................................................................................................... 10 Simulated Exchange configuration.............................................................................................. 11 Hardware resources .................................................................................................................... 11 Software resources ..................................................................................................................... 12 Exchange Server 2010 design ........................................................................................................ 13 Introduction to Exchange Server 2010 design ............................................................................ 13 Hyper-V virtual machine design .................................................................................................. 13 Exchange Server 2010 storage design ....................................................................................... 14 Exchange Server 2010 DAG design ........................................................................................... 15 Network design ............................................................................................................................... 18 Network design ............................................................................................................................... 18 Introduction to network design .................................................................................................... 18 Best practices for iSCSI .............................................................................................................. 18 Best practice for DAG network .................................................................................................... 18 Network configuration ................................................................................................................. 19 Test and validation .......................................................................................................................... 21 Introduction to test and validation ............................................................................................... 21 JetStress testing .......................................................................................................................... 21 Exchange 2010 DAG seeding performance validation ............................................................... 23 LoadGen testing .......................................................................................................................... 25 Database switchover validation................................................................................................... 29 Server switchover validation ....................................................................................................... 29

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 3

Datacenter switchover validation ................................................................................................ 30 Failover validation under load ..................................................................................................... 34 Lagged database copy recovery validation ................................................................................. 34 Conclusion ...................................................................................................................................... 38 Summary ..................................................................................................................................... 38 Key points.................................................................................................................................... 38 Next steps ................................................................................................................................... 38 References ...................................................................................................................................... 39 White paper ................................................................................................................................. 39 Product documentation ............................................................................................................... 39 Other documentation ................................................................................................................... 39 Additional information...................................................................................................................... 40 Introduction.................................................................................................................................. 40 Customize mailbox size in LoadGen 2010 .................................................................................. 40

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 4

Executive summary Business case

Microsoft Exchange Server 2010 introduces the database availability group (DAG) as the new high availability (HA) mechanism to replace previous integrated HA technologies. The validation of DAG mechanisms in Exchange 2010 is important for all organizations that are looking for e-mail up-time and performance. This solution uses low-cost Serial Advanced Technology Attachment (SATA) drives with native Exchange Server 2010 DAG protection for effective local HA and remote disaster recovery (DR). By testing and validating an Exchange 2010 DAG on an Iomega® StorCenter ix12-300r Network Storage Array, EMC has established detailed performance data, along with the reference architecture for small to medium commercial scenarios.

Product solution

The Iomega StorCenter ix12-300r Network Storage Array offers easy-to-use, powerful, and affordable network storage for any small business or remote office. Powered by enterprise-class EMC® LifeLine™ software, StorCenter ix12-300r is available in configurations starting at 4 terabytes (TB), and can be expanded up to 24 TB in a single array. The robust connectivity allows simultaneous multi-protocol file and iSCSI block-level access. High performance makes the ix12-300r an ideal candidate for e-mail and database applications or a fast backup target. High reliability features ensure maximum availability, including RAID with hot-swap drives and automatic rebuild, dual hot-swap power supplies, and redundant variable-speed hot-swap chassis cooling fans. This solution demonstrates how to build an Exchange Server 2010 environment on the Iomega StorCenter ix12-300r platform that integrates Microsoft Hyper-V virtualization technology. This solution also validates the Exchange Server 2010 DAG performance in this environment.

Key results

This white paper demonstrates the following benefits: • Reduced physical infrastructure footprint—By deploying the Exchange 2010 environment into a Microsoft Hyper-V virtualization platform, the number of physical servers needed in this solution is significantly decreased (with four HyperV root servers hosting 10 virtual machines). • Validated and tested performance—The test result shows Iomega StorCenter ix12-300r can be an excellent platform to house Exchange 2010. • Alternative for Exchange 2010 backups—By utilizing native Exchange Server 2010 DAG protection, customers now have the no-backup and no-RAID option for their Exchange environments so that they can fully utilize disk space in the storage array and can also reduce additional backup costs. • Local HA and remote DR—By deploying this site resiliency solution, customers achieve high availability for both local and remote sites and can easily recover the services in an event of server failure or site failure.

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 5

Introduction Purpose

The purpose of this solution is to build a replica of a common customer environment and validate the environment to provide performance results and best practices for designing Iomega StorCenter ix12-300r storage with Exchange Server 2010.

Scope

This white paper covers the following topics: • Build an Exchange Server 2010 environment with DAG on the Iomega StorCenter ix12-300r platform. Use DAGs for both local HA and remote DR, with four copies to provide for no-backup option and RAID 0 configuration. • Utilize Windows Server 2008 R2 Hyper-V for virtualization. • Test and verify the configuration of Exchange Server 2010 DAG. • Test and verify the seeding performance of Exchange Server 2010 in a RAID 0 configuration. • Test and verify the DAG failover performance under load.

Audience

This white paper is intended for: • EMC employees • EMC partners • Customers, including IT planners, storage architects, and administrators • Field personnel, who are tasked with implementing Microsoft Exchange Server 2010 solutions with the Iomega StorCenter ix12-300r storage

Terminology

The terms used in this white paper are defined in Table 1. Table 1. Terms and definitions

Term

Definition

Database Availability Group (DAG)

A DAG is a new database high availability feature in Exchange Server 2010. It is a set of Mailbox servers that uses continuous replication to provide automatic recovery in the event of failures. A DAG can contain up to 16 Mailbox servers, each one having a replicated copy of the production databases and log files.

Mailbox database copy

A mailbox database (.edb file and logs) that is either active or passive.

Lagged mailbox

A passive mailbox database copy that has a log replay lag

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 6

database copy

time greater than zero.

High availability

A solution that provides service availability, data availability, and automatic recovery from failures that affect the service or data (such as a network, storage, or server failure).

Microsoft JetStress 2010

Jetstress 2010 is a tool provided by Microsoft to verify the performance and stability of a disk subsystem before putting a Microsoft Exchange Server 2003, 2007 and 2010 server into production. Jetstress helps verify disk performance by simulating an Exchange disk Input/Output (I/O) load. Specifically, Jetstress simulates the Exchange database and log file loads produced by a specific number of users.

Microsoft LoadGen 2010

Microsoft Exchange Load Generator 2010 (LoadGen) is a simulation tool to measure the impact of MAPI, OWA, ActiveSync, IMAP, POP and SMTP clients on Exchange 2010 and 2007 servers. LoadGen allows users to test how a server running Exchange 2010/2007 responds to e-mail loads. These tests send multiple messaging requests to the Exchange server, thereby causing a mail load. LoadGen is a useful tool for administrators who are sizing servers and validating a deployment plan. Specifically, LoadGen helps administrators determine if each of the servers can handle the load to which they are intended to carry.

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 7

Technology overview Introduction to the key components

The following sections identify and briefly describe the technology and components used in the configuration: • Microsoft Exchange Server 2010 • Microsoft Hyper-V 2008 R2 • Iomega StorCenter ix12-300r Network Storage Array

Microsoft Exchange Server 2010

Microsoft Exchange Server 2010 is an enterprise e-mail and communication system that allows businesses and customers to collaborate and share information. It enables users to achieve new levels of reliability and performance with features that simplify the administration, protect communications, and meet the demands for greater mobility.

Microsoft Hyper-V 2008 R2

Hyper-V, the Microsoft hypervisor-based server virtualization technology, provides the cost savings of virtualization which enables customers to make the best use of their server hardware investments by consolidating multiple server roles as separate virtual machines (VMs) running on a single physical machine. Windows Server 2008 R2 introduces a new version of Hyper-V. It includes several core areas of improvement for creating dynamic virtual datacenters, including increased availability and improved management for virtualized datacenters, increased performance and hardware support for Hyper-V virtual machines, and improved virtual networking performance. For more information about Hyper-V 2008 R2, visit the Windows Server 2008 R2 website: http://www.microsoft.com/windowsserver2008/en/us/hyperv-r2.aspx

Iomega StorCenter ix12-300r Network Storage Array

The Iomega StorCenter ix12-300r Network Storage Array offers easy-to-use, powerful, and affordable network storage for any small business or remote office. Available in configurations starting at 4 TB, StorCenter ix12-300r can be expanded up to 24 TB in a single array without I/O interruption. With this ability to scale storage capacity, customers can size their storage environments by purchasing the capacity needed today, and then expand their systems as future needs grow. Additional functions such as user quotas and size-limiting capabilities offer greater control over storage allocation and distribution. High performance makes StorCenter ix12-300r an ideal candidate for e-mail and database applications or a fast backup target. Robust connectivity allows simultaneous multi-protocol file and iSCSI block-level access. High reliability features, including RAID with hot-swap drives and automatic rebuild, dual hot-swap power supplies, and redundant variable-speed hot-swap cooling fans, ensure the

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 8

maximum availability. Figure 1 illustrates an Iomega StorCenter ix12-300r Network Storage Array.

Figure 1.

Iomega StorCenter ix12-300r Network Storage Array

For more detailed information about the EMC Iomega StorCenter ix12-300r, visit the following website: http://go.iomega.com/en/products/network-attached-storage-nas/ix12-300r/ix12300r/?partner=4735#overviewItem_tab

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 9

Environment Physical environment

Figure 2 illustrates the overall physical architecture of the environment.

Figure 2.

Targeted customer profile

Overall physical architecture of the environment

The simulated targeted customer profile is listed in Table 2. Table 2. Targeted customer profile

Exchange Server 2010 profile

Value

Exchange 2010 user profile

20 messages sent/80 received per user per day

Read/write ratio

3:2

User count per Mailbox server

1,000 (250 active and 750 passive)

Mailbox size

4 GB

Target average message size

75 KB

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 10

Simulated Exchange configuration

Hardware resources

According to the customer profile, the Exchange Server 2010 environment is configured as described in Table 3. Table 3. Exchange server 2010 configuration

Exchange Server 2010 profile

Value

Number of Exchange 2010 users

1,000

Number of DAG

1

Number of servers per DAG

4

Number of DAG copies

4 (2 local, and 2 remote including 1 lagged copy)

Number of databases per server

20 (5 active and 15 passive)

Number of mailboxes per server

1,000 (250 active and 750 passive)

Number of mailboxes per database

50

Database size

200 GB

RAID type for DB/Log

RAID_0, 1 TB 5.9k rpm SATA

Database LUN size

300 GB

Log LUN size

20 GB

Table 4 shows the hardware resources used in this solution. Table 4. Hardware resource

Equipment

Quantity

Configuration

EMC Iomega StorCenter ix12-300r

4

12 x 1 TB 5.9k rpm SATA drives

IP switch

2

Cisco Catalyst 3750E

Physical server

7

Dell PowerEdge 710

Software version: 2.6.5.20864

CPU: 2 * Intel Xeon E5530 (2.4 GHz) RAM: 36 GB

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 11

Software resources

Table 5 shows the software used in this solution. Table 5. Software resource

Server role and tools

Version

Hyper-V Server

Windows Server 2008 R2 Enterprise Edition Hyper-V

Domain Controller and SCVMM server

Windows Server 2008 R2 Standard Edition

Exchange 2010 Mailbox Role

Exchange Server 2010 Enterprise Edition SP1

Exchange 2010 Hub and CAS roles

Exchange Server 2010 Standard Edition SP1

Microsoft JetStress 2010

14.01.0180.003 ESE version is 14.00.0639.019

Microsoft LoadGen 2010

14.01.0180.003

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 12

Exchange Server 2010 design Introduction to Exchange Server 2010 design

The design and testing principles applied in this environment demonstrate how Exchange users with large mailboxes can achieve good performance on Iomega StorCenter ix12-300r with SATA drives. Tests were conducted on the Microsoft Hyper-V virtualization platform utilizing minimal resources. The following sections provide the virtualization platform, server, and storage design guidelines for Exchange Server 2010.

Hyper-V virtual machine design

In this solution, the Microsoft Hyper-V virtualization platform was used. All the Exchange 2010 servers were deployed as Hyper-V virtual machines. To provide mailbox site resiliency, two sites were deployed. In the event that one site goes down, the other site can take over all the resources and client users can still access their mailboxes. Furthermore, two Exchange 2010 Mailbox servers are deployed in each site to achieve high availability locally. Each Mailbox server is set up on a separate Hyper-V host server for additional redundancy. Note: In this solution, the Mailbox servers are not designed to tolerate a concurrent local server failure and a remote site failure. From the HUB/CAS server’s perspective, the HUB/CAS combined role has a 1:1 CPU core ratio to the Mailbox server. So four HUB/CAS servers are deployed as virtual machines and each Hyper-V server hosts one of them. For the Active Directory (AD), each site has one physical domain controller server, and has one more domain controller deployed in Hyper-V virtual machines to provide high availability. In this way, AD also achieves HA both locally and remotely. Table 6 provides detailed information about the Hyper-V virtual machine configuration. Table 6. Hyper-V virtual machine configuration

Virtual machine server role

CPUs

Memory

Number

Domain Controller

2

4 GB

2

Exchange 2010 HUB/CAS server

2

8 GB

4

Exchange 2010 Mailbox server

2

12 GB

4

Note •

Microsoft provides detailed information about how to calculate memory and CPU requirements for Exchange Server 2010. For more information, visit the following websites: http://technet.microsoft.com/en-us/library/ee832793.aspx



http://technet.microsoft.com/en-us/library/ee712771.aspx

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 13

Exchange Server 2010 storage design

Microsoft Exchange Server 2010 has changed significantly since early versions of Exchange, particularly in terms of I/O and storage. Mailbox servers now can be defined as part of a DAG to provide automatic recovery at the individual mailbox database level instead of at the server level, and the I/O requirements in Exchange Server 2010 have been reduced from those in Exchange Server 2007. With these new features, customers can deploy much larger mailboxes than they could with earlier versions of Exchange Server. Exchange data can also reside on lower-speed disks such as SATA drives. For more information about Exchange Server 2010 store changes, visit the following website: http://technet.microsoft.com/en-us/library/bb125040.aspx This solution utilizes low-cost and high-capacity 1 TB SATA disks for Exchange data storage. RAID 0 is configured to provide better space utilization and optimal performance. The down-side with RAID 0 is that it provides for no protection if the drive is lost to hardware issues, and this is why four copies of the data were used. As outlined previously under normal operating conditions, each Exchange server and Iomega StorCenter ix12-300r storage array hosts 250 active users and 750 passive users, so three drives in the Iomega StorCenter ix12-300r are used in a RAID 0 configuration to provide data storage for 250 active users, and the remaining drives house data for passive DAG copies. In this way, the total of 12 drives in one Iomega StorCenter ix12-300r is divided into four RAID 0 storage pools, hosting mail for 1,000 users. Figure 3 shows the RAID 0 configuration on an Iomega StorCenter ix12-300r.

Figure 3.

RAID 0 configuration on an Iomega StorCenter ix12-300r

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 14

Table 7 shows the LUN size and disk utilization in this solution. Table 7. LUN size and disk utilization

Data type

Size

Calculation

Database LUN size

300 GB

50 users * 4 GB + 35% = 270 GB round up to 300 GB, where 35% reservation is for deleted items retention and index

Log LUN size

20 GB

50 users * 20 log * 7 days = 7 GB round up to 20 GB

Disk utilization

60%

Three 1 TB SATA drives in RAID 0 yield 2,700 GB space. The disk utilization is (300 GB + 20 GB) * 5 = 1,600 / 2,700 = 60%.

Note

In this solution, the LoadGen tool is used to initialize the Exchange database and index, which can take a significant amount of time to finish. Therefore, the user mailbox size is configured as 4 GB. To make full use of the storage space, customers can deploy 1,000 users with up to 7 GB mailbox size to achieve 96 percent disk utilization: (500 GB database LUN + 20 GB log LUN) * 5 = 2,600 / 2,700 = 96%

The virtual machine boot disks are set up as fixed virtual hard disks (VHDs), using Hyper-V root server local storage.

Exchange Server 2010 DAG design

DAG is the base component of the high availability and site resilience framework built into Microsoft Exchange Server 2010. A DAG is a group of up to 16 Mailbox servers that hosts a set of databases and provides automatic database-level recovery from failures that affect individual servers or databases. Consider the following points when designing the Exchange Server 2010 DAG configuration in this solution: •

To provide high availability, two copies of every mailbox database must be available on the local site. Place the active and passive copies on separate Mailbox servers and also on separate Hyper-V servers.



To provide site resiliency, one copy of every mailbox database must be available on the other site. In this way, if the Mailbox servers on one site fail or the mailbox databases become inaccessible, the passive mailbox database on the other site can take over and continue to serve client users.



One lagged copy is enabled for every mailbox database. The concept of lagged database copies was first introduced in Exchange 2007 Standby Continuous Replication (SCR). In SCR, customers can delay the time when the logs have to be replayed to the target, and delay the time before the log files are truncated. Exchange Server 2010 DAG also supports replay lag time and truncation lag time just like SCR in Exchange Server 2007, but the lag time for both replaying and deleting the logs is increased to 14 days. It can be implemented to protect against database logical corruption and is recommended when a Volume Shadow Copy Service (VSS) backup strategy

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 15

is not being deployed. This is known as Exchange Native Data Protection and implies that no VSS backups are deployed. For more information about lagged database copy and Exchange Native Data protection, visit the Microsoft Exchange Server TechCenter websites: http://technet.microsoft.com/en-us/library/dd979802.aspx http://technet.microsoft.com/en-us/library/dd876874.aspx In this solution, replay lag time is configured as 1.00:00:00 (1 day). Note



Although not implemented in this solution, it is recommended that database copies have two or more lagged copies. If there is only one lagged copy, it should be protected with RAID if possible. Lagged database copies should be blocked from possible activation to avoid losing the replay lag by allowing failovers to a lagged database copy. To do this, use the Suspend-MailboxDatabaseCopy cmdlet with the ActivationOnly parameter in the Exchange Management Shell (EMS) as follows: Suspend-MailboxDatabaseCopy –Identity \ -ActivationOnly To resume the ability for the lagged database copy to be activated, run the following cmdlet in EMS: Resume-MailboxDatabaseCopy –Identity \



Since this is a no-backup solution, no backup was taken to truncate log files. Therefore, it is important to enable circular logging for all the mailbox databases to prevent log files from growing indefinitely.



The datacenter activation coordination (DAC) mode should be enabled in a DAG node environment to prevent split brain syndrome, a condition that occurs when all networks fail and DAG members cannot receive heartbeat signals from each other. Split brain syndrome may also occur when network connectivity is severed between the datacenters. For more information, visit the Microsoft Exchange Server TechCenter website: http://technet.microsoft.com/en-us/library/dd979790.aspx



Isolation of logs and databases on different physical disks is no longer a requirement when DAG is implemented.

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 16

Figure 4 shows the DAG configuration in this solution.

Figure 4.

DAG configuration

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 17

Network design Introduction to network design

This section provides details about the network design in this solution and best practices for using an iSCSI storage array, such as an Iomega StorCenter ix12-300r.

Best practices for iSCSI

The best practices for connecting to an Iomega StorCenter ix12-300r using iSCSI are listed below: • Use dedicated switches for production and iSCSI networks. If this is not possible, create and configure vLANs to isolate iSCSI traffic from all other network traffic. • Configure network redundancy to provide fault tolerance and improve performance. • Ensure all ports on the switch are set to auto-negotiate 1000. • For iSCSI solutions, a 1 Gb Network Interface Card (NIC) is recommended as a minimum. • On each iSCSI NIC, perform the following actions: − Set all iSCSI NIC speeds to 1 Gb full − Disable Client for Microsoft Networks − Disable File and Printer Sharing for Microsoft Networks − Disable IPv6 if not being used. − Disable IPv4 Checksum Offload − Disable IPv4 Large Send Offload − Disable IPv6 Checksum Offload − Disable IPv6 Large Send Offload − Disable TCP Connection Offload (IPv4) − Disable TCP Connection Offload (IPv6)

Best practice for DAG network

Although a single network is supported, it is recommended that each DAG has at least two networks: a single MAPI network, which is used by other servers (like Exchange 2010 servers and directory servers) to communicate with the DAG member; and a single replication network, which is dedicated to log shipping and seeding. This provides network redundancy and enables the system to distinguish between a server failure and a network failure. In addition, perform the following actions on the network adapter for DAG replication network:

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 18

• Do not use default gateways on adapters for replication network. To provide network connectivity between each of the replication network adapters, use persistent static routes with Netsh.exe. For more information about how to use Netsh.exe, visit the website: http://technet.microsoft.com/en-us/library/cc725935%28WS.10%29.aspx • Disable Register this connection's addresses in DNS. • Disable Client for Microsoft Networks and File and Printer Sharing for Microsoft Networks. • If IPv6 is not used, disable the protocol on the server. • Make sure the MAPI NIC is listed first on the binding order list and then the replication NIC. Figure 5 shows this configuration under Network Connections > Advanced > Advanced Settings (to make the menu bar available in Windows Server 2008 R2, press the ALT key).

Figure 5.

Network configuration

Binding orders

In this solution, the storage used by the Exchange virtual machine for mailbox databases and log files is SCSI pass-through storage, which is configured at the host level and dedicated to one virtual machine. To achieve high availability, network teaming is configured on the Hyper-V server and network bonding is set up on the Iomega StorCenter ix12-300r Network Storage Array. On each Hyper-V server, two NICs are dedicated for the guest machine virtual network: one is for the production connection and the other is for Exchange Mailbox server DAG replication connection.

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 19

Figure 6 shows the network configuration of the Hyper-V server, guest machines, and storage array.

Figure 6.

Note

Network configuration

Figure 6 uses Hyper-V Server 2 as an example, which hosts one DC server, one Exchange HUB/CAS server, and one Exchange Mailbox server. The configuration is exactly the same on other Hyper-V servers, which host one Exchange HUB/CAS server and one Exchange Mailbox server only. More information about the physical architecture is provided in the “Physical environment” section.

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 20

Test and validation Introduction to test and validation

This section describes the validation and performance results for this solution. The following test scenarios were conducted to verify the Exchange Server 2010 DAG performance on an Iomega StorCenter ix12-300r: • Used Microsoft JetStress 2010 to verify disk performance by simulating an Exchange disk I/O load. • Validated the DAG seeding performance for both the local site and remote site. • Used LoadGen 2010 to verify the impact of MAPI clients on Exchange 2010 servers. • Validated the failover and switchover function of this Exchange Server 2010 database high availability design. • Validated the recovery process when using lagged database copy to restore lost or corrupt data.

JetStress testing

Jetstress 2010 was used to verify the performance and stability of the Iomega StorCenter ix12-300r Network Storage Array. Jetstress helps to verify disk performance by simulating Exchange disk I/O load. Specifically, Jetstress simulates the Exchange database and log file loads produced by a specific number of users. It is designed to test the performance of the Exchange storage subsystem before placing it in the production environment. While the Jetstress tool tests the performance of the Exchange storage subsystem before placing it in the production environment, it does not test the impact of the server CPU and memory configuration of MAPI user activity. In this solution, the following JetStress tests were performed as shown in Table 8. Table 8. JetStress test scenarios

Test

Description

1

Normal operation – Each Mailbox server hosts 250 active users.

2

Failover scenario – Each Mailbox server hosts 500 active users. This is to simulate a failover scenario that if one Exchange Mailbox server or one site encounters problems, the mailbox database fails over to other servers and each server will host double user mailboxes.

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 21

Table 9 shows the key performance counters in the JetStress testing and the threshold performance number provided by Microsoft. Table 9. Key performance counters in the JetStress testing

Performance counters

Target

Target Exchange transactional IOPS

User count * 0.12 (including 20% headroom). In this solution, 30 IOPS for a normal test and 60 IOPS for a failover scenario

Achieved database transactional IOPS

Exceed target IOPS

I/O database Reads average latency (ms)

Not to exceed 20 millisecond (ms)

I/O database Writes average latency (ms)

Not to exceed 20 ms

I/O log Writes average latency (ms)

Not to exceed 10 ms

Figure 7 provides a summary of the JetStress test data for normal operation. For a single Exchange Mailbox server, more than 55 IOPS is achieved over the target 30 IOPS. This additional headroom provides a buffer against I/O spikes and peak load. Disk latencies are all within the acceptable parameters, compared with Microsoft‘s best practices for Exchange 2010 performance as listed in Table 9.

Figure 7. JetStress test data summary with 250 users per server

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 22

Figure 8 shows a summary of the JetStress test data for the failover scenario. For a single Exchange Mailbox server, more than 76 IOPS is achieved over the target 60 IOPS. At the same time, disk latencies are all within the acceptable parameters. This approves that the Iomega ix12 storage can meet the I/O load requirement even in a server failover scenario.

Figure 8. JetStress test data summary with 500 users per server

Exchange 2010 DAG seeding performance validation

Seeding is a process in which a copy of a mailbox database is added to another Mailbox server. Seeding is required under the following conditions: • When a new passive copy of a database is created. • After a failover occurs in which data is lost as a result of the passive database copy having become diverged and unrecoverable. • When the system has detected a corrupted log file that cannot be replayed into the passive copy of the database. • After an offline defragmentation of any copy of the database occurs. • After the log generation sequence for the database has been reset to 1. A database copy can be seeded using either the active copy or an up-to-date passive copy as the source for the seed. To perform seeding, either use the UpdateMailboxDatabaseCopy cmdlet or the Update Database Copy wizard from the Exchange Management Console. When using the Update-MailboxDatabaseCopy cmdlet, use the -CatalogOnly parameter to specify that only the content index catalog for the database copy should be seeded, or use the -DatabaseOnly parameter to specify that only the database copy will be seeded. By default, both the database and

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 23

catalog are seeded. Table 10 shows the seeding performance results in this solution. Table 10.

Seeding performance results

Seeding scenario

Local-site seeding

Cross-site seeding

Seeding threads

Size

Seeding time

Throughput

Single database (database + index)

263.1 GB

3:00:47

87 GB/hour

Four databases (database + index)

1049.8 GB

3:36:00

292 GB/hour

Single database (database + index)

263.1 GB

3:17:35

80 GB/hour

Four databases (database + index)

1017.8 GB

4:01:19

253 GB/hour

Notes: • These results are based on the test environment configuration and can be different at the customer environment. • The cross-site seeding was performed over a 1 Gb network with no latency between sites. • In production environments, the content index is usually about 20 percent of the database size. It was 30 percent to 40 percent of the index size in this test environment due to the dynamic content generation feature in LoadGen. The total single replication source size (DB + Index) was approximately 260 GB to 270 GB. • Based on testing, if there are more than four seeding threads simultaneously, the database seeding tends to encounter errors and fail. So the recommended seeding thread is four at most in this solution. • During seeding, multiple network connections can be utilized to improve the seeding speed by using the Suspend-MailboxDatabaseCopy command with the -Network parameter. In this solution, two network connections were used when the seeding was performed with four database threads simultaneously. Update-MailboxDatabaseCopy –Identity \ SourceServer -Network Figure 9, Figure 10, and Figure 11 illustrate the network utilization during a four-thread seeding test. It shows that the database seeding consumes many network resources and customers should carefully plan the seeding to avoid overlapping with other network-intensive jobs.

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 24

Figure 9. Network utilization of a Windows iSCSI network

Figure 10. Port utilization of a Windows iSCSI network

Figure 11. Port utilization of an ix12 iSCSI network

LoadGen testing

LoadGen is a simulation tool to measure the impact of MAPI, OWA, ActiveSync, IMAP, POP, and SMTP clients on Exchange 2010 and 2007 servers. LoadGen allows customers to test how a server running Exchange 2010/2007 responds to email loads. These tests send multiple messaging requests to the Exchange server, which causes a mail load. LoadGen is a useful tool for administrators who are sizing servers and validating a deployment plan. Specifically, LoadGen helps organizations to determine if each of their servers can handle the load they are intended to carry. Note

Loadgen requires full deployment of the Exchange environment for validation testing. Customers should perform all LoadGen validation testing in an isolated lab environment where there is no connectivity to production data.

LoadGen provides some default mailbox size settings for testing: 2 MB, 50 MB, 75 MB, 100 MB, 250 MB, 1 GB, and 2 GB. Manually edit the configuration file to test a different mailbox size other than the default ones. For more information about how to customize the testing mailbox size, see the “Additional information” section.

EMC Business Continuity for Microsoft Exchange 2010 - Enabled by EMC Iomega ix12-300r and Microsoft Database Availability Groups—A Detailed Review 25

In this solution, the following LoadGen tests were performed to measure the performance of the Exchange infrastructure, as shown in Table 11. Peak load is enabled by setting “a simulation day” to four hours rather than eight hours (the total length of the simulation is still set to eight hours). This LoadGen configuration simulates the peak load by doubling the delivered message rate per second. The content index was not running during LoadGen testing. Table 11.

LoadGen tests of Exchange Infrastructure performance

Test

Description

1

Normal operation – Outlook 2007 online mode mailbox, 8 hours and 100% concurrency test with 100 messages MAPI profile under peak load.

2

Failover scenario - Outlook 2007 online mode mailbox, 8 hours and 100% concurrency test with 100 messages MAPI profile under peak load, but only half of the Exchange Mailbox servers handle all the user mailbox load (that is, two Exchange Mailbox servers hosting 1,000 users).

The validity of each test run is determined by comparing the results of selected performance counters with Microsoft-specified criteria. Performance counter data is collected at 15-second intervals for the duration of each 8-hour test run. The results of the first and the last hours are discarded. Results are averaged over the remaining test duration. Test 1: Normal operation This test is to validate the entire Exchange environment performance in a normal operating condition. Table 12 shows the LoadGen results in this test. The performance results are within the acceptable parameters compared with Microsoft‘s best practices for Exchange 2010 performance. Table 12.

LoadGen test results in normal operation

Performance Counter

Target

Test result

Hyper-V Hypervisor Virtual Processor (VP0-1)\% Guest Run Time

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