What is virtualization?

Welcome to the vSphere tutorial. This information will help you learn about virtualization concepts, components of VMware vSphere and the inventory, and using the vSphere Web Client to manage your virtual infrastructure.

What is virtualization?

Virtualization is an abstraction layer that breaks the hard connection between the physical hardware and the operating system. A virtual infrastructure is an enterprise-wide solution that provides fluid, powerful computing that maximizes resource utilization and cost savings.

Virtual machines are the key element to a virtual infrastructure. Virtualization allows you to run multiple virtual machines with heterogeneous operating systems and applications to run in isolation, side-by-side on the same physical machine.

Using virtualization, you can dynamically move resources where they are needed, and move processing where it makes most sense. This is possible because VMware detaches the operating system and its applications from the hardware they run on.

Physical vs. virtual

A virtual machine is a software computer that, like a physical computer, runs an operating system and applications. It has its own set of virtual hardware on which a guest operating system and its applications run. The operating system sees a consistent set of hardware regardless of the actual physical hardware components.

Virtual machines are not emulators or simulators. They are real machines that can do the same things physical computers can do and more. Because of the flexibility of virtual machines, physical computers become less a way to provide services (applications, databases, and so on) and more a way to house the virtual machines that provide those services.

Benefits of virtual machines

A physical machine is hard to move, difficult to copy, and bound to a specific set of hardware. Virtual machines are easy to copy and move because they are independent of physical hardware. Also, they are easy to manage because they are isolated from other virtual machines running on the same physical hardware and insulated from physical-hardware changes.

Virtual machines enhance infrastructure by providing:

• Freedom from physical hardware constraints
  Virtual machines allow the operation of heterogeneous operating systems running across heterogeneous hardware.
• Backup and recovery with little or no down-time
  You can configure virtual machines with operating systems and applications once and then clone them many times. Backing up a virtual machine is as easy as backing up a few files. In this way, virtual machines ensure fast deployment and reliability.
• Greater resource utilization
  Multiple virtual machines can run on the same physical server. In addition, consolidating computing power to fewer physical computers can substantially increase power savings in your enterprise
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How does vSphere work?

VMware vSphere is a system for managing your virtual infrastructure. VMware vCenter Server is a tool that manages multiple host servers that run multiple virtual machines.

With vCenter Server, you can quickly provision new server virtual machines and create a library of standardized virtual machine templates so your newly provisioned systems always conform to your datacenter requirements.

The vCenter Server lets you migrate running virtual machines between host servers so that you can perform hardware maintenance with minimal downtime. Other vCenter Server features allow you to balance virtual machine workloads across hosts and manage virtual machines for high availability and disaster recovery.