Windows Server 2008 Hyper-V Technology Primer
- What Is Server Virtualization and Microsoft Hyper-V?
- Choosing to Virtualize Servers
- Understanding Microsoft's Virtualization Strategy
- What's New in Hyper-V
- Determining What Is Needed to Virtualize Servers
- The Right Time to Implement Hyper-V
- Migrating from Microsoft Virtual Server 2005 and VMware
- Understanding the Administration of Virtual Guest Sessions
- Ensuring High Availability of a Hyper-V Host Server
- Summary
- Best Practices
IN THIS CHAPTER
- What is Server Virtualization and Microsoft Hyper-V?
- Choosing to Virtualize Servers
- Understanding Microsoft's Virtualization Strategy
- What's New in Hyper-V
- Determining What is Needed to Virtualize Servers
- The Right Time to Implement Hyper-V
- Migrating from Microsoft Virtual Server 2005 and VMware
- Understanding the Administration of Virtual Guest Sessions
- Ensuring High Availability of a Hyper-V Host Server
Hyper-V is a long-awaited technology that has been anticipated to help Microsoft leap past rival virtual server technologies such as VMware and XenServer. Although Microsoft has had a virtual server technology for a few years, the features and capabilities have always lagged behind its competitors. Windows Server 2008 was written to provide enhanced virtualization technologies through a rewrite of the Windows kernel itself to support virtual server capabilities equal to, if not better than, other options on the market. This chapter introduces the Hyper-V server role in Windows Server 2008 and provides best practices that organizations can follow to leverage the capabilities of server virtualization to lower costs and improve the manageability of an organization's network server environment.
What Is Server Virtualization and Microsoft Hyper-V?
Server virtualization is the ability for a single system to host multiple guest operating system sessions, effectively taking advantage of the processing capabilities of very powerful servers. Most servers in data centers run under 5% to 10% processor utilization, meaning that excess capacity on the servers goes unused. By combining the workloads of multiple servers onto a single system, an organization can better utilize the processing power available in its networking environment.
Virtualization as an IT Organization Strategy
Just 2 to 3 years ago, virtualization was used primarily as a test environment solution for information technology (IT) departments. If an IT administrator wanted to test new software, rather than building up a full physical server and loading software on that system, the administrator would install the software on a virtual server system and fiddle with the software off the virtual server. A virtual server enabled the IT administrator to load up several different test systems without purchasing or setting up separate computer systems. However, virtual servers were not considered reliable or robust enough to handle the day-to-day demands of an organization's IT needs. Much of that belief stemmed from the limitations of computer hardware capacity that existed just half a decade ago; server systems were underutilized but still taking up 20% to 30% of system capacity.
Virtualization Driven by Hardware Capabilities
Only recently, with the release of dual-core or quad-core processors and 64-bit operating systems, have servers gone from having 2 or 4 core processors to easily 8 to 16 core processors, and from 4GB of RAM to 16, 32, or 64GB of RAM. Now instead of running at 20% to 30% capacity, servers are running at 2% to 3% capacity.
Virtualization Driven by the Desire to Go "Green"
Whereas hardware provided significant excess capacity to consolidate server processes into fewer server systems, the social interest to go "green" has driven organizations to decrease their power consumption and improve their resource utilization. Virtualization enables an organization to decrease the number of physical computers they need to purchase, and in doing so also decreases the power and air-conditioning cooling demands that physical computer systems require. An organization that can decrease the physical number of its servers by 50% to 75% can decrease their electrical power requirements by a similar percentage.
Virtualization also decreases the computer data center "sprawl," whereas the increase of physical servers in the recent past caused organizations to continue to increase the square footage of their data centers. With virtualization physical server systems, an organization can decrease the size of their data centers and decrease the overall footprint required to host their information systems.
Virtualization Driven by Lower Costs
Many organizations now realize that fewer server systems and lower demands on electrical power, air-conditioning costs, and the decrease in data center space are lowering the cost of IT operations. To increase profitability, or just to manage overhead costs, virtualization enables organizations to decrease costs and better utilize IT resources.
Microsoft Hyper-V Server as a Role in Windows Server 2008
Microsoft has simplified the process of adding virtualization into a network environment by including Hyper-V virtualization in the x64-bit version of Windows Server 2008. As organizations install Windows Server 2008 into their environment, they can just run the Server Manager tool in Windows 2008 and choose to install the Hyper-V role, shown in Figure 1.1 (along with a system reboot); the Windows 2008 server is then ready to start adding virtual guests to the system.
Figure 1.1 Hyper-V as a Windows 2008 role.
Hyper-V on a Familiar Operating System
Unlike some other server virtualization systems that are hosted on the Linux operating system (VMware ESX) or proprietary host systems, Hyper-V runs right on a familiar Microsoft Windows Server operating system. Network administrators do not need to learn a new operating system, management system, or specialized tools. Early adopters of Hyper-V, even without documentation or training, have been able to install the Hyper-V server role, finding it just like installing any other server role (such as installing domain name service [DNS], media services, Internet Information Services [IIS] web services, and the like).
The administrative tools for Hyper-V, shown in Figure 1.2, are also just like any other administrative tool in Windows. Therefore, the creation of virtual guest sessions, the monitoring of those sessions, and the administration of guest sessions is a familiar process for IT administrators.
Figure 1.2 Hyper-V administrative tools.
The ease of learning, using, and supporting Hyper-V has been a huge factor in organizations adopting Hyper-V for their virtual server environments.
Microsoft Applications on a Microsoft Virtual Server
A concern for organizations relative to virtualization in a production environment is the support they will receive from their software vendors (Microsoft, Oracle, IBM, and the like). Whereas software vendors readily support their applications on physical hardware systems, they have not necessarily fully supported their applications on virtualized systems.
With the release of Hyper-V virtualization from Microsoft, however, Microsoft has openly announced full support for their current versions of applications running in a Hyper-V virtualized environment. So, products such as Exchange Server 2007 with Service Pack 1 and Microsoft Office SharePoint Server 2007 with Service Pack 1 are all directly supported. No longer will IT administrators have to worry about finger pointing resulting from server software not being supported by their vendor because the application was installed on a virtualized server rather than a physical server.
A single phone call to Microsoft tech support can provide an IT administrator support for both their Microsoft application and their Microsoft virtual server environment.
Hyper-V Support More Than Just Windows Guest Sessions
With the release of Hyper-V, Microsoft made a concerted effort to ensure that Hyper-V not only supports Windows guest sessions (like Windows 2003 and Windows 2008), but also non-Windows guest sessions running Linux. By providing support for a variety of guest sessions, Microsoft is enabling organizations to consolidate both their Windows and non-Windows server systems onto fewer Hyper-V host servers.