6.0.1

vSphere Concepts and Features 1
VMware vSphere™ leverages the power of virtualization to transform data centers into simplied cloud
computing infrastructures and enables IT organizations to deliver exible and reliable IT services.
The two core components of vSphere are VMware ESXi™ and VMware vCenter Server™. ESXi is the
virtualization platform on which you create and run virtual machines. vCenter Server is a service that acts as
a central administrator for ESXi hosts that are connected on a network. vCenter Server allows you to pool
and manage the resources of multiple hosts. vCenter Server provides many features that allow you to
monitor and manage your physical and virtual infrastructure.
Additional vSphere components are available as plugins that extend the functionality of the vSphere
product.
This chapter includes the following topics:
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“Virtualization Basics,” on page 13
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“Physical Topology of vSphere Data Center,” on page 14
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“vSphere Software Components,” on page 15
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“Client Interfaces for vSphere,” on page 17
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“vSphere Managed Inventory Objects,” on page 18
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“Optional vCenter Server Components,” on page 20
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“vCenter Server Plug-Ins,” on page 21
Virtualization Basics
A virtual machine is a software computer that, like a physical computer, runs an operating system and
applications. The hypervisor serves as a platform for running virtual machines and allows for the
consolidation of computing resources.
Each virtual machine contains its own virtual, or software-based, hardware, including a virtual CPU,
memory, hard disk, and network interface card.
Software called the hypervisor is installed on the physical hardware in a virtualized data center, and acts as
a platform for virtual machines. ESXi is the hypervisor in a vSphere environment. The hypervisor provides
physical hardware resources dynamically to virtual machines as needed to support the operation of the
virtual machines. The hypervisor allows virtual machines to operate with a degree of independence from
the underlying physical hardware. For example, a virtual machine can be moved from one physical host to
another, or its virtual disks can be moved from one type of storage to another, without aecting the
functioning of the virtual machine.
VMware, Inc.
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