Choosing a Virtual Configuration for Windows EBS
Applies To: Windows Essential Business Server
When you set up your virtualization environment, a physical server contains the Microsoft® Hyper-V™ technology that hosts and manages the Windows® Essential Business Server (EBS) 2008 virtual machines. The first step in the virtualization process is to decide on a server configuration. There are a variety of server configurations that you can use to virtualize Windows EBS. This topic describes the rationale and requirements for single server and multiple-server configurations.
The following table defines terms that are used throughout this document.
| Term | Definition |
|---|---|
Hypervisor |
A layer of software that sits just above the hardware and below one or more operating systems. Its primary job is to provide isolated execution environments, which are called partitions. The hypervisor controls and arbitrates access to the underlying hardware. For more information, see the Microsoft Web site (https://go.microsoft.com/fwlink/?LinkID=128205). |
Host (parent) partition |
A partition that is created first and that owns all of the resources that the hypervisor does not own, including most devices and system memory. The host partition hosts the virtualization stack and creates and manages the guest partitions. When the Hyper-V role is configured and the server is rebooted, the installation of the Windows Server® 2008 operating system that was the native operating system on the system becomes the operating system in the host partition of the Hyper-V server. |
Guest (child) partition |
An isolated environment on a Hyper-V server that is configured to hold a guest operating system and to provide hardware resources to that operating system. |
Hyper-V host |
The physical server that is hosting Hyper-V and the operating system running inside the host partition. |
Hyper-V guest |
The operating system and the environment within a Hyper-V virtual machine that is running inside a guest partition. |
Hyper-V virtual machine (VM) |
A software-based computer within a physical computer. A virtual machine emulates a complete hardware system, from processor to network card, in a self-contained, isolated software environment. Each Windows EBS server can be configured to run in its own virtual machine. |
Virtual hard disk (VHD) |
A file stored on the native disk system of the physical computer. From within a virtual machine, the VHD appears as though it is a physical hard disk. |
Virtual network |
An emulation of a physical network. You can configure a virtual network to provide access to local or external network resources for one or more virtual machines. |
You can use the Hyper-V technology in Windows Server 2008 to run a virtualized instance of Windows EBS on a single physical server. In this configuration, Windows Server 2008 is installed as the host operating system, and the three Windows EBS servers are installed as guests in three virtual machines.
A single server configuration provides the following advantages:
Initial configuration Windows Server 2008 and the Hyper-V role are installed and configured only once.
Licensing One Windows Server 2008 license is required.
Backup and restore A single server uses a backup process that is simpler, and that demands fewer resources.
Space and cooling A single server requires less rack space and less cooling.
The Hyper-V technology in Windows Server 2008 requires a 64-bit (x64) processor, hardware-assisted virtualization, and hardware data execution protection. For information about systems that support the x64 architecture and Hyper-V, see the Windows Server catalog at the Microsoft Web site (https://go.microsoft.com/fwlink/?LinkId=111228).
The following table lists the minimum (and recommended) hardware requirements that you need for a single physical server to run the host operating system and the three virtual machines for Windows EBS.
| Hardware | Minimum Requirement |
|---|---|
Processor |
64-bit (x64) quad-core or dual dual-core, hardware-virtualization-enabled (dual quad-core recommended) |
System memory |
12 gigabytes (GB) (16 GB or more recommended) |
Storage capacity |
Four disk drives:
Note It is strongly recommended that you use different physical hard drives for the virtual hard drives for the three Windows EBS virtual machines. Disk partitions should be sized according to the Windows EBS minimum hardware requirements. You should use a redundant array of independent disks (RAID) for redundancy in the host system and in each Windows EBS virtual machine. |
Network adapters |
Note If you are evaluating Windows EBS, you plan to connect it only to virtual machines that are hosted on the same physical server, and you do not need to manage the server remotely, you need only a single network adapter. |
Note
If you plan to install Windows EBS from physical media, a DVD drive is required.
In a two or more server configuration, each physical server has Windows Server 2008 and Hyper-V installed, and one or more virtualized Windows EBS servers. For example, you can install the Security Server as a virtual machine on one physical server, and then you can install the Management Server and the Messaging Server as virtual machines on another server.
A multiple server configuration provides the following advantages:
Lower hardware requirements Servers with less memory and storage space can be used, which allows you to repurpose existing hardware.
Redundancy Critical services such as the domain controller and the DNS Server service can be placed on separate servers to eliminate a single point of failure.
Performance Disk reads can be spread over multiple spindles on separate servers, which can reduce disk latency.
Backup and restore Multiple servers provide more options and flexibility for data and system backup.
For information about non-virtual server hardware requirements, see Microsoft Web site (https://go.microsoft.com/fwlink/?LinkID=119200).
The hardware requirements for servers hosting virtual Windows EBS servers are the same as non-virtual Windows EBS servers with the following exceptions:
Memory On each host server, add 1 GB (2 GB recommended) to the memory that is required for Windows Server 2008.
Hard drives On each host server, add 10 GB (40 GB recommended) to the total disk space requirements for the installation of Windows Server 2008.
Network interface cards (NICs) The Management Server and the Messaging Server should have two NICs. The Security Server should have three NICs.