Exchange 2010 System Requirements
Applies to: Exchange Server 2010
Before you install Microsoft Exchange Server 2010, we recommend that you review this topic to ensure that your network, hardware, software, clients, and other elements meet the requirements for Exchange 2010. In addition, make sure you understand the coexistence scenarios that are supported for Exchange 2010 and earlier versions of Exchange.
Supported Coexistence Scenarios
The following table lists the scenarios in which coexistence between Exchange 2010 and earlier versions of Exchange are supported.
Coexistence of Exchange 2010 and earlier versions of Exchange Server
| Exchange version | Exchange organization coexistence |
|---|---|
Exchange 2000 Server |
Not supported |
Exchange Server 2003 |
Supported |
Exchange 2007 |
Supported |
Mixed Exchange 2007 and Exchange Server 2003 organization |
Supported |
Exchange 2000 Server
You can't upgrade an existing Exchange 2000 organization directly to Exchange 2010. You must first upgrade the Exchange 2000 organization to either an Exchange 2003 or Exchange 2007 organization, and then you can upgrade the Exchange 2003 or Exchange 2007 organization to Exchange 2010. We recommend that you upgrade your organization from Exchange 2000 to Exchange 2003, and then upgrade from Exchange 2003 to Exchange 2010. For more information about upgrading from Exchange 2000, see Planning an Upgrade from Exchange 2000 and Upgrading to Exchange 2007.
Network and Directory Servers
The following table lists the requirements for the network and the directory servers in your Exchange 2010 organization.
Network and directory server requirements for Exchange 2010
| Component | Requirement |
|---|---|
Schema master |
By default, the schema master runs on the first Windows Server 2003 or Windows Server 2008 or Windows Server 2008 R2 domain controller installed in a forest. The schema master must be running any of the following:
|
Global catalog server |
In each Active Directory site where you plan to install Exchange 2010, you must have at least one global catalog server running any of the following:
For more information about global catalog servers, see What is the Global Catalog. |
Domain controller |
In each Active Directory site where you plan to install Exchange 2010, you must have at least one writeable domain controller running any of the following:
|
Active Directory forest |
Active Directory must be at Windows Server 2003 forest functionality mode or higher. |
Ipv6 Support |
IPv6 is supported only when IPv4 is also used; a pure IPv6 environment isn't supported. Using IPv6 addresses and IP address ranges is supported only when both IPv6 and IPv4 are enabled on that computer, and the network supports both IP address versions. If Exchange 2010 is deployed in this configuration, all server roles can send data to and receive data from devices, servers, and clients that use IPv6 addresses. Exchange 2010 support is similar to support for Exchange Server 2007. For more information, see IPv6 Support in Exchange 2007 SP1 and SP2. |
Directory Server Architecture
The use of 64-bit Active Directory domain controllers increases directory service performance for Exchange 2010. For more information about Exchange 2010, the Mailbox server role and Active Directory ratios, see the "Active Directory Server and Mailbox Server Ratios" section in Understanding Server Role Ratios and Exchange Performance.
Note
In multi-domain environments, on Windows Server 2008 domain controllers that have the Active Directory language locale set to Japanese, your servers may not receive some attributes that are stored on an object during inbound replication. For more information, see Microsoft Knowledge Base article 949189, A Windows Server 2008 domain controller that is configured with the Japanese language locale may not apply updates to attributes on an object during inbound replication.
Installing Exchange 2010 on Directory Servers
For security and performance reasons, we recommend that you install Exchange 2010 only on member servers and not on Active Directory directory servers. However, you can't run DCPromo on a computer running Exchange 2010. After Exchange 2010 is installed, changing its role from a member server to a directory server, or vice versa, isn't supported.
Hardware
The recommended hardware requirements for Exchange 2010 servers vary depending on a number of factors including the server roles that are installed and the anticipated load that will be placed on the servers. For information about minimum, maximum, and recommended hardware configurations for Exchange 2010 servers, see Performance and Scalability.
Hardware requirements for Exchange 2010
| Component | Requirement | Notes |
|---|---|---|
Processor |
|
It's supported to install the Exchange management tools on a computer that has a 64-bit processor. For more information, see Install the Exchange 2010 Management Tools and Prepare Active Directory and Domains. |
Memory |
Varies depending on Exchange features that are installed |
For detailed information about memory requirements for Exchange 2010, see Understanding Memory Configurations and Exchange Performance. |
Paging file size |
The page file size minimum and maximum must be set to physical RAM plus 10 MB |
The recommended page file size also accounts for the memory that's needed to collect information if the operating system stops unexpectedly. On 64-bit operating systems, memory can be written as a dump file to the paging file. This file must reside on the boot volume of the server. For more information about the configuration options that are available for memory dump data, see Knowledge Base article 254649, Overview of memory dump file options for Windows Vista, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows XP, and Windows 2000. |
Disk space |
|
The minimum space requirements detailed here don't account for disk subsystem requirements for adequate performance. |
Drive |
DVD-ROM drive, local or network accessible |
None. |
Screen resolution |
800 x 600 pixels or higher |
None. |
File format |
Disk partitions formatted as NTFS file systems, which applies to the following partitions:
|
None. |
For more information about planning your hardware for Exchange 2010, see the following topics:
- Understanding Processor Configurations and Exchange Performance
- Understanding Memory Configurations and Exchange Performance
- Understanding Server Role Ratios and Exchange Performance
Operating System
The following table lists the supported operating systems for Exchange 2010.
Supported operating systems for Exchange 2010
| Component | Requirement |
|---|---|
Operating system on a computer that has a 64-bit processor |
One of the following:
|
Operating system for installing the Exchange management tools on a computer that has a 64-bit processor |
One of the following:
|
Important
The release-to-manufacturing (RTM) version of Exchange 2010 doesn’t support being run on computers with the United States Federal Information Processing Standards (FIPS) compliant settings enabled. If you have FIPS enabled on computers running Windows Server 2008 SP2 or Windows Server 2008 R2, Exchange 2010 RTM will not function correctly. For more information, see Knowledge Base article 811833, The effects of enabling the "System cryptography: Use FIPS compliant algorithms for encryption, hashing, and signing" security setting in Windows XP and in later versions of Windows.
Support for Outlook and Entourage
Exchange 2010 supports the following versions of Microsoft Office Outlook and Microsoft Entourage for Mac:
- Outlook 2010
- Outlook 2007
- Outlook 2003
- Entourage 2008 for Mac, Web Services Edition
Hardware Virtualization
Microsoft supports Exchange 2010 in production on hardware virtualization software only when all the following conditions are true:
The hardware virtualization software is running:
- Windows Server 2008 with Hyper-V technology
- Windows Server 2008 R2 with Hyper-V technology
- Microsoft Hyper-V Server 2008
- Microsoft Hyper-V Server 2008 R2
- Any third-party hypervisor that has been validated under the Windows Server Virtualization Validation Program.
The Exchange guest virtual machine:
- Is running Microsoft Exchange 2010.
- Is deployed on the Windows Server 2008 with SP2 or Windows Server 2008 R2 operating system.
- Doesn't have the Unified Messaging server role installed. All Exchange 2010 server roles, except for the Unified Messaging server role, are supported in a virtualization environment. This is due to the real-time response requirements associated with voice communications with the Unified Messaging server role.
- Meets all of the requirements set forth previously in this topic.
The storage used by the Exchange guest machine for storage of Exchange data (for example, mailbox databases or Hub transport queues) can be virtual storage of a fixed size (for example, fixed virtual hard disks (VHDs) in a Hyper-V environment), SCSI pass-through storage, or Internet SCSI (iSCSI) storage. Pass-through storage is storage that's configured at the host level and dedicated to one guest machine. All storage used by an Exchange guest machine for storage of Exchange data must be block-level storage because Exchange 2010 doesn't support the use of network attached storage (NAS) volumes. Also, NAS storage that's presented to the guest as block-level storage via the hypervisor isn't supported. The following virtual disk requirements apply for volumes used to store Exchange data:
Virtual disks that dynamically expand aren't supported by Exchange.
Virtual disks that use differencing or delta mechanisms (such as Hyper-V's differencing VHDs or snapshots) aren't supported.
Note
In a Hyper-V environment, each fixed VHD must be less than 2,040 GB. For supported third-party hypervisors, check with the manufacturer to see if any disk size limitations exist.
Only management software (for example, antivirus software, backup software, or virtual machine management software) can be deployed on the physical root machine. No other server-based applications (for example, Exchange, SQL Server, Active Directory, or SAP) should be installed on the root machine. The root machine should be dedicated to running guest virtual machines.
Microsoft doesn't support combining Exchange high availability solutions (database availability groups (DAGs)) with hypervisor-based clustering, high availability, or migration solutions that will move or automatically failover mailbox servers that are members of a DAG between clustered root servers. DAGs are supported in hardware virtualization environments provided that the virtualization environment doesn't employ clustered root servers, or the clustered root servers have been configured to never failover or automatically move mailbox servers that are members of a DAG to another root server.
Some hypervisors include features for taking snapshots of virtual machines. Virtual machine snapshots capture the state of a virtual machine while it's running. This feature enables you to take multiple snapshots of a virtual machine and then revert the virtual machine to any of the previous states by applying a snapshot to the virtual machine. However, virtual machine snapshots aren't application aware, and using them can have unintended and unexpected consequences for a server application that maintains state data, such as Exchange. As a result, making virtual machine snapshots of an Exchange guest virtual machine isn't supported.
Many hardware virtualization products allow you to specify the number of virtual processors that should be allocated to each guest virtual machine. The virtual processors located in the guest virtual machine share a fixed number of logical processors in the physical system. Exchange supports a virtual processor-to-logical processor ratio no greater than 2:1. For example, a dual processor system using quad core processors contains a total of 8 logical processors in the host system. On a system with this configuration, don't allocate more than a total of 16 virtual processors to all guest virtual machines combined.
When calculating the total number of virtual processors required by the root machine, you must also account for both I/O and operating system requirements. In most cases, the equivalent number of virtual processors required in the root operating system for a system hosting Exchange virtual machines is 2. This value should be used as a baseline for the root operating system virtual processor when calculating the overall ratio of physical cores to virtual processors. If performance monitoring of the root operating system indicates you're consuming more processor utilization than the equivalent of 2 processors, you should reduce the count of virtual processors assigned to guest virtual machines accordingly and verify that the overall virtual processor-to-physical core ratio is no greater than 2:1.
The operating system for an Exchange guest machine must use a disk that has a size equal to at least 15 GB plus the size of the virtual memory that's allocated to the guest machine. This requirement is necessary to account for the operating system and paging file disk requirements. For example, if the guest machine is allocated 16 GB of memory, the minimum disk space needed for the guest operating system disk is 31 GB.
In addition, it's possible that guest virtual machines may be prevented from directly communicating with fibre channel or SCSI host bus adapters (HBAs) installed in the root machine. In this event, you must configure the adapters in the root machine's operating system and present the LUNs to guest virtual machines as either a virtual disk or a pass-through disk.
Root Machine Storage Requirements
Each root machine has minimum disk space requirements that must be met:
- Root machines in some hardware virtualization applications may require storage space for an operating system and its components. For example, when running Windows Server 2008 with Hyper-V, you will need a minimum of 10 GB to meet the Windows Server 2008 R2 System Requirements for the operating system. Additional storage space will also be required to support the operating system's paging file, management software, and crash recovery (dump) files.
- Some hypervisors maintain files on the root machine that are unique to each guest virtual machine. For example, in a Hyper-V environment, a temporary memory storage file (BIN file) is created and maintained for each guest machine. The size of each BIN file is equal to the amount of memory allocated to the guest machine. In addition, other files may also be created and maintained on the host machine for each guest machine.
Exchange Server Storage Requirements
The following are the requirements for storage connected to a virtualized Exchange server:
- Each Exchange guest machine must be allocated sufficient storage space on the root machine for the fixed disk that contains the guest's operating system, any temporary memory storage files in use, and related virtual machine files that are hosted on the host machine. In addition, for each Exchange guest machine, you must also allocate sufficient storage for the message queues on the Hub Transport and Edge Transport servers and sufficient storage for the databases and log files on Mailbox servers.
- Storage used by Exchange should be hosted in disk spindles that are separate from the storage that's hosting the guest virtual machine's operating system.
- Configuring iSCSI storage to use an iSCSI initiator inside an Exchange guest virtual machine is supported. However, there will be reduced performance in this configuration if the network stack inside a virtual machine isn't full-featured (for example, not all virtual network stacks support jumbo frames).