About Question com.enthuware.ets.scwcd.v5.2.119 :

[ETS User]

<filter-mapping>
<filter-name>FilterA</filter-name>
<servlet-name>RedServlet</servlet-name>
</filter-mapping>

Is this filter-mapping declaration from DD valid... As per my knowledge url-pattern is mandatory and either filter-name or servlet-name should be there...

Can you please clarify

[admin]

As per Section 14.4 of Servlet 3.0 Specification:

The value of the filter-name must be one of the filter declarations in the deployment descriptor. The matching request can be specified either url-pattern or servlet-name.