The vSphere Upgrade Guide describes how to upgrade from earlier versions of VMware® ESX™, ESXi, and VMware vCenter™ Server to ESX 4.1/ESXi 4.1 and vCenter Server 4.1.

This guide includes the following tasks:

Upgrade to vCenter Server 4.1 from vCenter Server 4.0.

Install vCenter Server 4.1 on a different machine and keep a VirtualCenter 2.5 or higher database. You would do this if you are upgrading from a 32-bit server to a 64-bit server, for example.

Upgrade to ESX 4.1/ESXi 4.1 from ESX 4.0/ESXi 4.0.

Upgrade VMware Tools and virtual hardware.

To learn how to simplify and automate your datacenter upgrade, see the vSphere Update Manager Administration Guide.

If you have legacy versions of ESX, ESXi, and VirtualCenter, and you want to migrate to VMware vSphere™ 4.1 by performing fresh installations that do not preserve existing data, see the following manuals:

ESX and vCenter Server Installation Guide

ESXi Installable and vCenter Server Setup Guide

ESXi Embedded and vCenter Server Setup Guide

This book is intended for anyone who needs to upgrade from earlier versions of ESX/ESXi and vCenter Server to ESX 4.1/ESXi 4.1 and vCenter Server 4.1. The information in this manual is written for experienced Microsoft Windows or Linux system administrators who are familiar with virtual machine technology and datacenter operations.

VMware Technical Publications provides a glossary of terms that might be unfamiliar to you. For definitions of terms as they are used in VMware technical documentation, go to http://www.vmware.com/support/pubs.

VMware welcomes your suggestions for improving our documentation. If you have comments, send your feedback to docfeedback@vmware.com.

The vSphere documentation consists of the combined VMware vCenter Server and ESX/ESXi documentation set.

The following technical support resources are available to you. To access the current version of this book and other books, go to http://www.vmware.com/support/pubs.

Online and Telephone Support

To use online support to submit technical support requests, view your product and contract information, and register your products, go to http://www.vmware.com/support.

Customers with appropriate support contracts should use telephone support for the fastest response on priority 1 issues. Go to http://www.vmware.com/support/phone_support.html.

Support Offerings

To find out how VMware support offerings can help meet your business needs, go to http://www.vmware.com/support/services.

VMware Professional Services

VMware Education Services courses offer extensive hands-on labs, case study examples, and course materials designed to be used as on-the-job reference tools. Courses are available onsite, in the classroom, and live online. For onsite pilot programs and implementation best practices, VMware Consulting Services provides offerings to help you assess, plan, build, and manage your virtual environment. To access information about education classes, certification programs, and consulting services, go to http://www.vmware.com/services.