The primary objective of this chapter is not to give a summary of everything else in this book?which is essentially a guide to everything that is new in IIS 6, but instead to show you how to upgrade from a previous version of IIS to IIS 6 as quickly and painlessly as possible.
There are, of course, two versions of IIS that most people are going to migrate from?IIS 4 and IIS 5. You might also be upgrading or migrating a Web site from an IIS 5.1 installation on a Windows XP machine to Windows Server 2003.
Whatever the source version, there are essentially two avenues to take when performing the migration. The first is to upgrade your existing machine, and the second is to create a new server and migrate the content.
We'll start off in this chapter by looking at the major differences between IIS 4 and IIS 5 and the new IIS 6. Then we'll look at the upgrade process?that is, upgrading your host operating system from an older Windows NT 4.0 or Windows 2000 server product. This will include a look at the areas in which you will need to make changes after the upgrade to get your machine up and running again.
The upgrade process, though, is not always practical. For starters, it assumes you want to continue running the Web site on the same machine. Often, you will be migrating to new hardware at the same time, and you might also be taking the opportunity to improve the platform, as well as the Web serving environment.
This is where the IIS Migration Tool comes in; it enables you to move an IIS installation from one machine to another, transferring the configuration information and Web site files and data. We'll be taking a closer look at the IIS Migration Tool in this chapter.
The final sections of this chapter concentrate on some specific issues that you might come across after an upgrade has taken place.