Web Agent Guides › Web Agent Configuration Guide › Protecting Web Applications › Custom Error Handling For Applications

Custom Error Handling For Applications

Custom error handling allows you to make error information relevant to your application. To customize applications for users, you can add the HTML text displayed by HTTP 500, HTTP 401, and HTTP 403 error pages or, with the exception of 401 errors, you can redirect the user to a URL that points to a custom error page or application.

You can configure customized handling for the following types of errors:

• Server errors—the Agent uses the ServerErrorFile for error pages that result from HTTP 500 web server errors. These error codes are passed to the custom error pages and include:
  • Problems because the Web Agent cannot read values from required HTTP headers.
  • Advanced authentication cookies cannot be parsed or contain an error status.
  • Connectivity problems between the Web Agent and the Policy Server.
• Access Denied errors—the Agent uses the file specified in the Custom401ErrorFile parameter to display customized text for the standard 401 access denied message. These errors occur when a user does not have the appropriate privileges to access a resource.

  Note: Some web servers may append text of their own to the custom text. Consequently, the response pages for these servers will not be completely customized.

• Require cookies errors—if the RequireCookies parameter is set, the Web Agent sets a cookie during basic authentication. If this cookie is not returned by the browser with the basic credentials, the error page designated by the ReqCookieErrorFile parameter is returned, and the Agent denies the user access to the web server.
• Cross-site scripting errors—the Agent uses the file specified in the CSSErrorFile parameter for error pages that result from HTTP 403 cross-site scripting errors. Cross-site scripting can compromise the security of a Web site.

After you create these HTML files or applications, direct the Web Agent to the custom error pages or URLs.

Note: For an Apache server being used as a proxy or reverse proxy server, the Apache Agent will not return custom SiteMinder error pages, but will return the standard Apache HTTP 500 and 403 error pages.