Troubleshooting 404 "File Not Found" Errors 

Use

By default, the Web Container issues a short message to the client in cases of 404 “File Not Found” errors. This message contains information about the requested resource that is missing, the application alias of the application to which this resource belongs, as well as the name of the application itself (following the pattern <provider-name>\<application-name>). Such limited information hides security-sensitive details (such as the absolute path to the resource on the local file system), and is therefore not sufficient for debugging purposes. If you encounter a 404 “File Not Found” error and need to debug the problem, you have to adjust the Web Container tracing facilities to force it to generate details about the error.

Features

To generate debugging information, you must enable tracing on the Web Container using the TraceLevel property of the Web Container Service as described in Enable and Configure Tracing for Web Applications. Then, depending on whether the missing resource is a JSP page or a servlet class, you need to increase the severity level of the corresponding trace location as described below.

Missing JSP Pages

If the requested JSP page is not found within the Web application’s resources and you want to debug the problem, you have to set the severity level of the com.sap.engine.services.servlets_jsp.client.RequestInfoServer trace location to Info or higher. This forces the Web Container to write the absolute path where it looks for the JSP in the local file system to the corresponding trace file (defaultTrace.trc by default).

Missing Servlet Classes

To debug the errors when the requested servlet’s class cannot be loaded, you need to set the severity level of the com.sap.engine.services.servlets_jsp.client.ServletResponse trace location to Warning or higher. This forces the Web Container to write the application classloader’s resources to the corresponding trace file (defaultTrace.trc by default).

For more information about configuring trace locations using the Log Configurator service in the Visual Administrator, see Adding, Editing, and Removing Log Controllers.