Migrating a Web Server to IIS 5.0

Comparing NES and IIS 5.0

Terminology

Here are some essential terms used in NES with explanations of their equivalents in IIS 5.0.

Hardware Virtual Server In NES, a “hardware virtual server” is a site with a separate IP address; the term implies a number of Web sites on a single computer, each with a separate IP address. The counterpart in IIS 5.0 is a virtual server. As with NES hardware virtual servers, each virtual server in IIS 5.0 has its own domain name and IP address.
Software Virtual Server In NES, a “software virtual server” is a site that may share an IP address with one or more other sites. In IIS 5.0, you can assign any number of sites to a single IP address and distinguish them by using host headers, but no special term is employed to describe them.
Multiple Instances of the Server In NES, you host multiple Web sites on one computer by using multiple instances of the server if:
- The operating system does not have strong thread support.
- The operating system does not allow a single process to schedule threads on more than one processor.
- Multiple instances of the server provide full process isolation, protecting a Web site from failure should another site on the same system crash.
  It isn’t appropriate to run multiple instances of IIS 5.0, because IIS 5.0 running on Windows 2000 Server offers thread support across multiple processors, full configuration of each site hosted by the server, and process isolation for applications.
Server Manager Server Manager is the NES administration tool equivalent to the IIS snap-in for MMC.
Directory Aliases In NES, you can map an alias such as this:
/admin-offices/student
to a real directory such as this:
/admin-offices/studaffairs/cpc
In IIS 5.0 a virtual directory corresponds to an alias. You can use the New Virtual Directory Wizard to create a virtual directory. To start the wizard, in the IIS snap-in select the Web site for which you want to define a virtual directory, click the Action button, point to New, and then select Virtual Directory. For more information, see the “Creating Virtual Directories” topic in the IIS 5.0 online product documentation.