Replacing IIS with the Sun ONE or Apache Web servers (aka IIS Exorcism)

Introduction

Because of security and stability concerns with Microsoft?s Internet Information Server (IIS), many organizations are interested in migrating their applications to either a new Web server or to UNIX/Linux. This White Paper focuses on running ASP applications using the Apache or Sun ONE Web Server running on Microsoft Windows NT/2000. Depending on your needs, this is also a good interim step before a full migration to UNIX or Linux. Once complete, we suggest reviewing our how to guide for "Developing Cross-Platform ASP Applications" before proceeding with future ASP development projects.

Migrating ASP Applications to the Apache or Sun ONE Web Server running on Windows NT/2000

Moving an ASP Application to another web server, while staying within the Windows environment, is a very simple task. Below are a list of steps to perform, and a list of potential issues that you may encounter when performing the migration.

STEP 1: Just Do It!

You will be amazed at how simple the process can be. Please read the entire document, though, before proceeding.

STEP 2: Install the New Web Server

Install the Sun ONE Web Server (iWS) or Apache on the same machine that is running IIS. Be sure to turn off IIS first to avoid port conflicts between the two Web servers on the same machine.

Note: Please reference the Sun ONE Active Server Pages web site for supported Web server products and versions.

STEP 3: Install Sun Chili!Soft ASP for Windows

For more information see the product documentation .

STEP 4: List Virtual Directories

List all virtual directories used by the ASP application under IIS. These may also be referred to as "Web Shares" within the Windows operating system.

STEP 5: Create Matching Virtual Directories

Create "Additional Document Directories" if using iWS, or "Aliases" if using Apache to match those virtual directories used under IIS. If you are not familiar with these terms, please consult the appropriate Web server documentation for how to set these up properly.

STEP 6: Set Configuration Files

The ASP Application may rely on the need to automatically load a default asp page. While all web servers have the default ability to read index.html or home.html , you will need to add the default.asp or index.asp file name to your web servers configuration files for them to perform this task.

• In iWS 6.x, you need to add these file names to the Index Filenames list, which is located under Document Preferences .

• For Apache, you will need to add these file names to the httpd.conf files DirectoryIndex directive.

STEP 7: Test the ASP Application

From a browser, enter the URL to your ASP Application.

Potential Issues

Issue: COM objects that are registered in MTS

Solution: Remove these from MTS and reregister under the operating system itself using regsrv32.

Issue: ISAPI filters or objects

Solution: Unfortunately these types of objects are written specifically to the IIS API (Application Programming Interface). They will need to be rewritten as NSAPI (for iWS), or Apache module objects.

Note: Remember that ISAPI is the main target for the Code Red and Nimda viruses, not just the IIS web server.

Issue: ASP 3.0 code features or functions.

Solution: Microsoft ASP is currently at version 3.0. The differences between ASP 2.0 and 3.0 are very minor, however there are a couple of functions that were introduced that Sun ONE Active Server Pages currently does not support. To determine if these functions are used within your ASP Application, you will want to search your asp code for the syntax of Server.Execute and Server.Transfer .

Both of these features will be added to a future release of Sun ONE Active Server Pages, however in the meantime, you will need to recode these sections.

For almost all Server.Execute lines, you can replace them with an HTML <include> statement and get the same results.

<!-- #include virtual="/migration/includes/include.asp"-->

For the Server.Transfer code sections, you can try using a Response.Redirect . This causes the browser to the do the redirect instead of the server, which is a little bit more noticeable by the end user, but should serve a similar purpose, depending on how it is used.

Response.Redirect ("/migration2/sample2.asp")