Summary form only given. In this paper, we suggest a realistic methodology for testing robustness of real-time component-based systems (RTCBS). A RTCBS system is described as a collection of components where each component is specified by a nominal and a degraded specification, modeled as a timed input-output automaton (TIOA). Further, the communication of the whole system is also specified by its nominal and degraded specification. We extract test sequences from the nominal specification and we inject automatically faults in order to model hostile environments. Then, we present an adequate test architecture consisting of the system under test (SUT) of components, and a distributed tester that consists of a set of coordinating testers. Each tester is dedicated to test a single SUT component. A test execution algorithm with an approach to handle testers coordination and execution delay is presented. Testing the SUT is divided into two phases. In the first phase, the tester tests the robustness of each component in isolation. If all components are robust according to the inserted hazards, in the second phase, we use the nominal and degraded specification of the whole system to check the robustness of communications between components.