Servlets can be triggered by HTTP clients even if they are not defined on web.xml files if the Invoker Servlet is active. You can check if the Invoker Servlet is being used by following these steps:
1. Log in to Visual Admin
2. Click on Log Configurator under Services
3. Go to Locations tab
4. Navigate to ROOT Location -> com -> sap -> engine -> services -> servlets_jsp -> server -> servlet -> InvokerServlet
5. Change the severity from ERROR to WARNING
6. Save and Apply to all "server nodes"
You can check if InvokerServlet is used by checking if there are entries in the default trace files containing the pattern com.sap.engine.services.servlets_jsp.server.servlet.InvokerServlet
The invoker servlet is disabled by default on NetWeaver 7.3. You can disable it in NW 04 by following these instructions:
1. Update J2EE engine as recommended in SAP note 1445998.
2. Start the Config Tool
3. Go to Global Server Configuration under Cluster-data tree
4. Under Services, navigate to servlet_jsp
5. Select EnableInvokerServletGlobally key under Global properties list
6. Set the value to false and save the changes
7. Restart the cluster (Dispatcher + J2EE nodes)
If any of your applications is set to use the invoker servlet, and you have disabled it or you have upgraded to NW 7.3, you will notice the following error:
Error: Servlet with class <class name> cannot be loaded.