How To Integrate IIS6 and Apache Tomcat

How To Integrate IIS6 and Apache Tomcat By Glenn Barnas / InnoTech Consulting Group www.innotechcg.com This is a step by step guide to installing Apache Tomcat 6.x on systems running IIS 6.0. The process should work on other combinations of IIS and Tomcat with minimal adjustments. System Configuration: For this installation, I used the latest versions of software available during May, 2007. Windows Server 2003 Standard Edition (no change for Enterprise) w/ SP-2 Internet Information Services (IIS) 6.0 Sun Java Runtime JRE 6.0 Update 1 Apache Jakarta Tomcat version 6.0.13 The isapi_redirect.dll version 1.2.22 Install the Java Runtime Environment Launch the JRE installer. When prompted, choose a custom installation. I disable the browser integration, media support, and change the install path as shown. Click Next to start the install. Fig. 1 Java JRE Setup

Fig. 2 JRE Installation Complete I prefer to run an automated install for this the command line I used is shown below. You will need to reflect the correct JRE.exe file name, and possibly change the location of the log file. jre-6u1-windows-i586-p.exe /s ADDLOCAL=jrecore INSTALLDIR=%ProgramFiles%\Java\Jre IEXPLORER=0 MOZILLA=0 JAVAUPDATE=0 REBOOT=Suppress WEBSTARTICON=0 /L %SYSTEMDRIVE%\Temp\JRE6setup.log If you use the automated install command, Java Automatic Updates are disabled. This is our preferred setting on servers, so we can control the what and when updating process. If you manually installed Java, you can disable the automatic updates in the Java control panel.

Configuration of Java and Tomcat Both Java and Tomcat need environment variables defined so applications can locate the folders that they are installed to. Open the System Properties dialog box and select the Advanced tab. (right-click My Computer and choose Properties) Click the Environment Variables button at the bottom of the dialog box. Fig. 3 System Properties Dialog Box Fig. 4 Environment Variables Dialog Box Click New on the System (lower) section of the Environment Variables dialog box. The applications will not work with User variables! When prompted, add a new system variable called JAVA_HOME Set the value to the location where Java was installed. We consider Java a system application, so it is installed to C:\Program Files. Fig. 5 Setting the Java Environment Variable While we are here, define the CATALINA_HOME system variable that Tomcat requires. Specify the path where you have decided to install Tomcat. We consider this an external application, so it is installed to the application drive E:\Apps\Tomcat in this case. Fig. 6 Setting the Tomcat Environment Variable

Installing Tomcat We are ready to begin the Tomcat installation at this point. Since Tomcat is designed to work with several different web servers, it is not delivered with any components or configuration files for specific web servers. Since this is the case, and IIS requires specific components and configuration files, I prefer to put them in place before the installation of Tomcat. Preparation Having decided to install Tomcat to E:\Apps\Tomcat, start by creating some of the folders that Tomcat will use. We need to place two.properties files into the /conf folder, and put the isapi_redirect.dll file into the /bin/win32/i386 folder. The location of the redirector DLL is up to you, but this is the standard location used by Tomcat in the past. In the steps below, <TOMCAT> refers to the folder where Tomcat is installed, as specified in the CATALINA_HOME environment variable you defined earlier. Create the <TOMCAT>\conf folder Create the <TOMCAT>\bin\win32\i386 folder Copy the isapi_redirect.dll file to <TOMCAT>\bin\win32\i386 Create a workers.properties file in the <TOMCAT>\conf folder. Copy the following lines to that file to create a default configuration for testing. # Define 1 real worker using ajp13 worker.list=worker1 # Set properties for worker1 (ajp13) worker.worker1.type=ajp13 worker.worker1.host=localhost worker.worker1.port=8009 Create a uriworkermap.properties file in the <TOMCAT>\conf folder. Copy the following lines to that file to create a default configuration for testing. This assumes that the root of the Tomcat examples folder is called examples. This is the default installation method for this version. /examples/*=worker1 /examples/*.jsp=worker1 /examples/servlet/*=worker1 Copy the following lines to a file called isapi.reg, and merge this registry file into your server s system registry. Be sure to edit the 3 path definitions to reflect your configuration before merging the registry file! Windows Registry Editor Version 5.00 [HKEY_LOCAL_MACHINE\SOFTWARE\Apache Software Foundation\Jakarta Isapi Redirector] [HKEY_LOCAL_MACHINE\SOFTWARE\Apache Software Foundation\Jakarta Isapi Redirector\1.0] "extension_uri"="/jakarta/isapi_redirect.dll" "log_file"="e:\\apps\\tomcat\\logs\\isapi.log" "log_level"="debug" "worker_file"="e:\\apps\\tomcat\\conf\\workers.properties" "worker_mount_file"="e:\\apps\\tomcat\\conf\\uriworkermap.properties" You will want to edit the.properties files after the basic configuration is working to reflect your production environment. These are simply sample files to illustrate the relationship between workers and URIs. These files will be reviewed in some detail at the end of this document. Launch the Tomcat Installer Run the apache-tomcat-6.0.13.exe command to start the installation process. Click next on the splash screen, and I Agree on the license agreement screen.

When prompted to choose components, select Full for the first Tomcat installation so you have access to all of the example.jsp and Servelet files. For production installations, choose Custom, select Tomcat and all its sub-items, and de-select everything else. Fig. 7 - Tomcat Setup Dialog for Custom Install After choosing the components appropriate for your installation, you can select the install location. Browse to the folder you specified in CATALINA_HOME. As I mentioned earlier, we prefer to not install application software on the drive containing the O/S. Fig. 8 Define the installation folder

Define the HTTP/1.1 Connector Port and Admin ID/Password on the next screen. The Connector Port is the TCP/IP port that the Tomcat service will be listening on. If no other web server is utilizing this port, accept the default of 8080, otherwise choose an available port. Define an appropriate user name and password for web-based Tomcat administration. Be sure to follow your company s guidelines for secure passwords on production servers. Fig. 9 Configuring the Tomcat Connector port and Admin password The installer will locate your JRE path change it only if necessary. Fig. 10 Configuring the JVM/JRE path Click Install to complete the Tomcat installation process. When the installation completes, you will be presented with the opportunity to start the Tomcat service and view the Readme file. It is OK to

start the service at this time (since we already put the needed configuration files in place), and it is a good idea to review the Readme file. Fig. 11 Tomcat Installation is complete Verify that the installation has added a new service called Apache Tomcat (Tomcat6). Check that it is running, and that it is set to start automatically. Fig. 12 The Apache Tomcat service Test the Tomcat Installation On the system where you installed Tomcat, launch a web browser and connect to http://localhost:8080. You should see the Tomcat home page display.

Fig. 13 Default Tomcat web page on port 8080 You should take a few moments to test the JSP and Servlet examples to verify that everything is functioning properly. Fig. 14 Testing the Tomcat installation

Integrating IIS and Tomcat Since we adhere to strict Best Practice standards for IIS installations, I want to explain our configuration before continuing. We do not use the inetpub folder structure at all. We instead create a webfiles folder on the application drive. In the webfiles folder, we create a subfolder for each web instance, including the Default instance. Each of these instance subfolders has a web subfolder that becomes the root of the web instance. This provides some physical isolation between multiple web instances on a single system. It also permits folders to be created within a web application that are not directly part of the web structure. Preparation Before beginning the IIS/Tomcat integration, I prepared the IIS web server to have a Default web instance, and an application instance that would employ Tomcat. You can see this configuration in Figs. 15 and 16. I placed simple default.htm files in the root of each web instance that clearly identified the web instance that was returning the page. The home page message reported that the Default or Primary Production instance had replied. These pages helped in troubleshooting during the integration process. Fig. 15 Web Site Configuration Fig 16 Web Folder Structure You do not have to follow this structure for the IIS/Tomcat integration to work. This information is presented so that you can make sense of the remaining configuration settings and adapt them to your environment. In many cases, you will need to point to web applications outside of the default web data structure!

Fig 17 Sample Home Page to Identify Web Instance IIS Configuration jakarta Virtual Directory All of the following configurations will take place in the IIS Management console. Create a virtual directory called jakarta the spelling and case is significant! The path should reference the location of the isapi_redirect.dll file (<TOMCAT>/bin/win32/i386 by default). Check the Execute box. Fig. 18 Virtual Directory Alias Fig. 19 Virtual Directory Path

Fig. 20 Virtual Directory Access Permissions IIS Configuration Define Application Pool It is recommended that each web instance run with its own application pool. If you are configuring Tomcat to support an application web instance, create a separate application pool for Tomcat and change the web instance configuration to utilize it. Fig. 21 New Application Pool Fig. 22 Define application pool IIS Configuration Web Service Extension In the IIS Manager, right-click on the Web Service Extensions object and select New Web Service Extension. Enter an extension name of Tomcat, enable the checkbox Set extension status to Allowed, then click Add and browse to the path where the isapi_redirect.dll is located. Select the file and click OK. Verify that the Tomcat extension appears in the list with an Allowed status (Fig. 25).

Fig. 23 Add a web service extension Fig. 24 Specify path to isapi_redirect.dll Fig. 25 Web Service Extensions showing Tomcat extension and Allowed status IIS Configuration Define the Tomcat ISAPI Filter The web instance needs to know that it should utilize the ISAPI redirection filter. This is done by registering it in the application web site properties. Open the properties panel of the web instance you are configuring to operate with Tomcat. Select the ISAPI Filters tab and click the Add button. Set the filter name to tomcat, and browse to the location of the isapi_redirect.dll file. Click OK. The status and priority values will not display (or show * Unknown * ) until the first time the redirector is loaded. The filter will not load until the first time it is needed.

Fig. 26 Add ISAPI Filter Fig. 27 Web Properties dialog box At this point, configuration is complete. Run iisreset to reinitialize the web server environment. Any.JSP or servlets placed within the physical web structure will be intercepted by the isapi filter, although the uriworkermap.properties file will need to refer to the path where the.jsp or servlet files have been placed. This relationship will become clear when you perform the next step, which configures the Tomcat example files. IIS Configuration Tomcat Examples This is the part of the configuration that most often fails to function. This is likely due to not recognizing the relationship between the workers file, uriworkermap file, and IIS itself. Our example workers.properties file defines a single worker thread worker1 for testing purposes. It defines the ajp13 protocol, binds to localhost on port 8009. These values are appropriate for most configurations that perform local redirection. You can define multiple worker threads to support multiple instances or application paths. Simply add more names to the declaration line, and duplicate the specification lines, editing them for each worker s name. The example uriworkermap.properties file maps requests for specific application paths to specific workers. This file is configured to map the Tomcat /examples folder path to a targeted worker called worker1. Since we only defined one worker in the workers.properties file, the mapping file maps everything to that worker. If you tried to access http://localhost/examples right now, you d experience a 404 error. This is because IIS is not aware of that path! Think about where the /examples path is try http://localhost:8080/examples. Of course, it works because the web server built into Tomcat (listening on port 8080) knows that the /examples URI is physically located at E:\Apps\Tomcat\webapps\examples. IIS has no knowledge of this location (yet), so it returns the 404 error. Let s make IIS recognize this location by creating a virtual directory. Create a virtual directory called examples. The path should reference the location of the tomcat examples folder (<TOMCAT>\webapps\examples by default).

Fig. 28 Virtual Directory Alias Fig. 29 Virtual Directory Path Fig. 30 Virtual Directory Access Permissions Click Next to complete the installation. Now, when you browse to http://localhost/examples/index.html, you should see the following page display. Now that IIS can find the physical path, it can pass the request to the ISAPI filter, and Tomcat can return the pages.

Fig. 31- Tomcat examples page

Now that the example pages are working, you might want to add some of your own.jsp code to the IIS web instance. If you create a \JTest folder in your web root and put some sample files there (I copied the basic-arithmetic.jsp file from the Tomcat examples to the JTest folder for my test.), the URI http://localhost/jtest/mytest.jsp will not work (yet). That is because.jsp is not a valid mime time for IIS, so IIS simply reports that it can t find (deal with) the file. Older versions of IIS would have displayed the source of the file, using a default Text mime type. Remember the uriworkermap.properties file? It only has a reference to the /examples path assigned to Worker1. Add the following lines to it so references to /jtest can be assigned to a worker: /jtest/*=worker1 /jtest/*.jsp=worker1 Refresh your browser and you should see a different error message. This message now comes from Tomcat instead of IIS, proving that the redirector is now assigning the work to Worker1. Fig. 32 Tomcat error page You are seeing this error for the same reason that IIS presented 404 errors for the /examples path earlier. You created the /jtest folder in the IIS physical path this time Tomcat is not aware of it! We need to edit the server.xml file to tell Tomcat how to reference this path. Open server.xml, look for your <host> definition. The Tomcat sample file will look something like this: <Host name="localhost" appbase="webapps" unpackwars="true" autodeploy="true" xmlvalidation="false" xmlnamespaceaware="false"> Add this line to tell Tomcat how to map references to the /jtest path: <Context path="/jtest" docbase="e:\\webfiles\\ltu\\web\\jtest"></context> Restart Tomcat and refresh your browser window http://localhost/jtest/mytest.jsp should now properly display the page!

Summary The key to integrating IIS and Tomcat is recognizing that you actually have two web servers running. Requests are sent first to IIS, which must forward (redirect) them to the Tomcat web server. It does this by invoking the redirector, which scans the request and decides whether it should forward the request to Tomcat. If it does, Tomcat handles the request, otherwise, IIS handles it. The redirector (and Tomcat) make the decision to handle the request only if key criteria are met. Is it a.jsp or Servlet file? Is a worker available for the URI? Another important point to remember is that web servers translate the logical web paths to physical disk paths. If the logical path of the web server can t reach the physical path, you ll get a 404 error. This means that if you try to access content in one web server s physical path from the other web server, you better have some kind of configuration defined that allows that. For IIS, it means defining a Virtual Directory to map the web logical path to a physical folder. For Tomcat, you need to define the <Context> in server.xml to accomplish the same thing. Be aware that for my testing, I copied specific files basic-arithmetic.jsp to my jtest folder in IIS because it had no dependencies on other files. You can t do this with many of the other examples because they reference external files and java beans that haven t been mapped in IIS. This is certainly possible, but was more than I wanted to present in a basic example.