Book Image

Learning VMware vSphere

By : Rebecca Fitzhugh, Abhilash G B
Book Image

Learning VMware vSphere

By: Rebecca Fitzhugh, Abhilash G B

Overview of this book

Computer virtualization is a method to enable the running of multiple application workloads on a machine to achieve efficient utilization and reduce the number of physical machines in a data center. This has now become the foundation of many modern day data centers. What began as a technology to virtualize x86 architecture has now grown beyond the limits of a server’s hardware and into the realm of storage and network virtualization. VMware is currently the market leader in developing data center virtualization solutions. This book goes into the details of designing and implementing VMware solutions that form the foundation of a VMware infrastructure. The book begins by introducing you to the concepts of server virtualization followed by the architecture of VMware’s hypervisor – ESXi and then by its installation and configuration. You then learn what is required to manage a vSphere environment and configure advanced management capabilities of vCenter. Next you are taken through topics on vSphere Networking, Storage, ESXi Clustering, Resource Management and Virtual Machine Management. You will then be introduced to SSL Certificate Management and its use in a vSphere environment. Finally, you will learn about the lifecycle management of a vSphere environment by effectively monitoring, patching and upgrading vSphere components using Update Manager. By the end of the book, you will know how to use VMware’s vSphere suite of components to lay the foundation of a modern day virtual infrastructure.
Table of Contents (18 chapters)
Learning VMware vSphere
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface

Storage I/O Control (SIOC)


Before we define or discuss what SIOC control is, there are a few concepts that form the basics and also explain the need for a mechanism like SIOC.

ESXi runs a local host scheduler to balance the I/O between the virtual machines. This means that if there are virtual machines churning a considerable amount of I/O (more than normal), then it is important to make sure that the other virtual machines residing on the same datastore remain unaffected, in a manner that they should be allowed to issue I/O to the device. This is achieved by controlling the volume of I/O each of the participating virtual machines can issue, with the help of per-vmdk shares. This works pretty much like the CPU or Memory shares. The default virtual disk share value is 1000, high being 2000 and low being - 500. The disk with a relatively higher share value will get to issue a larger volume of I/O operations to the device.

Now, all of this will work just fine as long as the datastore is seen...