VCA-DCV VMware Certified Associate on vSphere Study Guide

VCAD-510

Robert Schmidt, Dane Charlton

• Editore: Sybex
• Anno: 2015
• ISBN:
  9781118919682
• Edizione: 1
• Argomento: Computer Science
• Categoria: Certification Guides in Computer Science

Use this expert guide to prepare for the VCA-DCV exam

VCA-DCV VMware Certified Associate on vSphere Study Guide: VCAD-510 is a comprehensive study guide for the VMware Certified Associate – Data Center Virtualization exam. Hands-on examples, real-world scenarios, and expert review questions cover the full exam blueprint, and the companion website offers a suite of tools to help you prepare for the exam including practice exams, electronic flashcards, and a glossary of key terms. In addition, the website includes videos that demonstrate how to complete the more challenging tasks. Focused on practical skills, this study guide not only prepares you for the certification exam, but also for the duties expected of a VCA.

The VMware Certified Associate-Data Center Virtualization certification targets those with limited virtualization and VMware data center technology experience, providing a springboard to the popular VMware Certified Professional-Data Center Virtualization certification. Virtualization has become a high priority among organizations, and credentialed professionals are in high demand. This guide helps you prove a certain level of foundational skill in basic virtualization technology, including the vSphere suite's Infrastructure Services, Application Services, and vCenter Server. Topics include:

• Explaining data center virtualization concepts
• Identifying the core components of vSphere
• Networking and storage planning/configuration with vSphere
• Correlating VMware solutions to common business challenges

The VCA-DCV certification is the only one with no instructor-led training requirement, so a thorough study guide is an invaluable tool in you exam preparation. This book not only covers the full exam, but also provides practice designed to actually improve the skills used every day on the job. VCA-DCV VMware Certified Associate on vSphere Study Guide is more than just test prep—it's job prep.

Chapter 1
Intro to Virtualization

THE VCA-DCV TOPICS COVERED IN THIS CHAPTER INCLUDE THE FOLLOWING:

• ✓ Identify and explain the concept of data center virtualization
  • Explain data center virtualization
  • Differentiate physical and virtual data center components
  • Identify data center virtualization benefits

This chapter covers the basic concepts of data center virtualization and challenges addressed by that virtualization. You’ll look at physical data center components and learn to differentiate between them. Then you will go over the advantages of data center virtualization and specific VMware products. (We discuss these specific products further in future chapters.) Finally, you will learn about some of the tools available online to help with the VCAD510 exam. By the end of this chapter, you will be able to define data center virtualization, differentiate between physical and virtual components, and list specific benefits of data center virtualization.

What Is Data Center Virtualization?

This section presents data center virtualization in a broad sense. It provides some background in order to give some context and introduces some of the vocabulary so you can join in on virtualization conversations around the water cooler.

The short explanation of data center virtualization is that it is a combination of physical hardware converted to software to allow greater utilization of the physical hardware, thereby increasing efficiency and reducing the amount of hardware needed. Data center virtualization is abstract—there is no physical entity that you can touch. Fortunately, virtual data center components can be considered the same as physical data center components. There are more similarities between a physical network card and a virtual network card than there are differences.

Today’s modern data center includes virtualization at the root. Many devices that used to be physical can now exist totally in the virtual world. By leveraging virtualization, many logical devices can be created from one physical device. For example, the network card in a VMware ESXi host, through virtualization, can be many network cards—a virtual network card presented to each virtual machine on the host. Similarly, all the physical hardware devices that make up the physical host that is running the VMware hypervisor (ESXi) are presented to each virtual machine on the host.

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The Hypervisor

In the VMware world, the hypervisor is the ESXi software. A hypervisor like ESXi plays the traffic cop for software resources. This allows multiple virtual machines to share the same physical hardware, which is the definition of consolidation.

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Of course, this is only where the good stuff starts.

Virtualization Then and Now

I have been working with computers for a really long time. When I started working with computers, a 10 MB hard drive provided a lot of storage. Most business computers had between 640 KB and 1 MB of memory. A lot has changed over the years, but one thing remains the same: businesses want to get as much return on investment as possible. It is easy to see the benefit of saving space or a little memory when you multiply that amount by a large number of computers. Not to mention the savings on data center power and cooling.

Back then, a company that specced out a new computer would have to buy a server that could handle the load at peak load time (Figure 1.1). That is, a server would have to be able to handle the most work requested of it at any given time. For example, if a new web server was needed, it might have to be able to handle 500 simultaneous users once a day. So, the new server would need to be big enough to handle that load even though that load occurred only once a day. As a result, companies typically had a large number of servers, and most of the servers were idle a lot of the time.

Figure 1.1 Before virtualization, servers were sized for peak load.

For this reason, virtualization makes a lot of sense. Virtualization is nothing new. Large mainframe companies such as IBM came up with the idea of virtualization decades ago and initially used it as a development environment more than anything else.

When virtualization started being leveraged in the PC world, it also was primarily used for development. When I started using VMware Workstation, it was an easy way to bring up an entire infrastructure on a PC. This represented a tremendous advantage. Now you can develop a solution that requires domain controllers, file servers, DNS servers, and application servers without buying a lot of hardware. Even when VMware ESX was released, many companies realized this could save them a lot of money but used it only for development environments. In fact, VMware once had an enterprise solution to provide developers with isolated environments. It was called VMware Lab Manager. Lab Manager was discontinued a few years ago. The functionality of Lab Manager was replaced by vCloud Director. However, vCloud Director requires Enterprise Plus licensing and takes some effort to reproduce what Lab Manager did.

Some companies, however, realized the potential of using VMware for real production environments. And the perception of VMware changed. Now, any company with a lot of servers has to at least entertain the idea of using virtualization. And companies that leverage virtualization see some amazing benefits. In fact, now the goal is more than a return on investment; it is the flexibility that virtualization provides along with some enterprise-level solutions from VMware.

I troubleshoot servers all day. When an application owner needs help with a server, I really hope it is a virtual server, because troubleshooting a virtual server can be much easier than troubleshooting a physical server. When troubleshooting a physical server, the problem is often a hardware or driver issue. I don’t see, or rarely see, those kinds of problems with virtual servers. And, as the percentage of virtual servers increases in a company, some things just get easier. Now there is very little reason to have any physical application servers.

It was not too long ago that many companies deployed VMware but did not trust it enough to run business-critical applications such as enterprise email systems (for example, Microsoft Exchange) or enterprise database environments (for example, Microsoft SQL Server) on it. VMware made a push to change companies’ minds and virtualize these busy servers. VMware made this push in different ways. But the one that counted was making VMware’s products better. VMware is now more stable, scalable, and cost-effective. Many companies deploy Exchange and SQL Server, among other business-critical applications, on the VMware virtual platform. And VMware can dynamically scale resources to varying needs on the fly. For example, determining the right-sized physical server for running SQL can be difficult because demands on SQL can change so rapidly. You buy a brand new server to run SQL, and then si...