Apache and Tomcat communication changes

SUSE Linux Enterprise Server 10
 

Apache 2.2 and Tomcat 5.0
Communication between Tomcat and Apache is not available through the mod_jk.so module using JkMount configuration directives.

The resolution requires enabling different modules to cause this to operate, and then configuration changes. First, to ensure the appropriate modules are enabled :
 

1. Open YaST.
2. Click "Network Services".
3. Click "HTTPD Server".
4. Click onto the modules tab.
5. Locate "proxy" in the list, and ensure it is enabled.
6. Check for "proxy_ajp" in the list. If not there, click"Add" and then choose the "proxy_ajp" module. Ensure it is enabled.
7. Additionally, enable the "rewrite" module. This is not required in certain circumstances (listed in the additional notes section of this document).

At this point, restarting Apache should enable mod_proxy and mod_proxy_ajp when loading. We now need to configure the web application handling mechanism. First, determine if Apache will be serving images and HTML, but tomcat serves JSP files all from inside of the same directory. If this is not the case, configuration is easily done by changing the

JkMount /webapplication/* ajp13

configuration line to

ProxyPass /webapplication/ ajp://localhost:8009/webapplication/

And restart apache. If a single directory contains both HTML and JSP files, the ProxyPass directive will not handle the *.jsp mechanism. Instead, the rewrite module (step 7 in enabling the appropriate modules) is required, and a special RewriteRule directive is used. The syntax for the RewriteRule directive :

RewriteRule REQUEST_URI TARGET [FLAGS]

For example :

JkMount /gw/*.jsp ajp13

Would be rewritten as :

RewriteRule ^/gw(.*\.jsp)$ ajp://localhost:8009/gw/$1 [P]

This rule simply enables the proxy module using RewriteRule for anything that matches the parameter (the [P] flag). The example above will send anything hit with /gw/*.jsp and forward it to tomcat using the ajp protocol on port 8009 for the localhost.

Once the configuration is set up, restart Apache, and it should now be communicating with Tomcat.

In SUSE Linux Enterprise Server 10, Apache 2.0 had been phased out, and Apache 2.2 was used. This web server configuration no longer used the mod_jk.so extensions for communication with Tomcat, as that could be accomplished with newer core modules for apache, specifically the proxy and proxy_ajp modules.