Non-stop and highly available applications need to be dynamically adapted to new conditions in their execution environment, to new user requirements or to some situations usually unpredictable at build-time. Bank, aeronautic, mobile and Internet applications are well known examples of applications requiring the dynamic reconfiguration. On the other hand the development complexity and cost constitute an important problem for the creation of applications supporting to be dynamically reconfigured. The work we present in this paper is centered around the dynamic reconfiguration of component-based applications. It is dedicated to describing DYVA, a virtual dynamic reconfiguration machine. The virtual aspect of DYVA means its independence from a particular application or a particular component model, which enhances its genericity and its reusability. Keywords. Dynamic reconfiguration, Component model, Metamodel, DYVA.