The management of modern IT systems is increasingly costly and complex. Indeed, the architecture of these systems is generally monolithic and does not allow for dynamic adaptation to external changes (failures, performance variation, security attacks, etc). In this thesis, we are interested in the management of Middleware, subject of less work than hardware and operating systems management.First, we propose an approach transforming legacy Middleware to administrable (easily configurable and adpatable) ones. This approach consists in changing their architecture to an explicit component-based one. Second, we propose a management system automating the deployment, the dynamic code update and the recovery from failure operations.As a use case, we considered a legacy J2EE application server, JOnAS. JonasALaCarte is the name of the obtained J2EE server. We show that our approach to the administration simplifies the server configuration and deployment in distributed environments. Furthermore, we introduced new management features to the server such as the dynamic code update and the self-recovery from failures.
