Recently, storage-centric configurations, such as NAS and SAN architectures, have attracted attention in advanced Data processing. For these configurations, scalability, flexibility, and availability are key features, and central control is unsuitable. We propose autonomous disk to enable distributed control in the storage-centric configurations. Autonomous disk configure a cuter in a network, and implement the above key using ECA rule with a distributed directory. The combination of the rules and directory also manages load distribution, and has a capability of reconfiguring the cluster automatically. In this paper, we focus on the cluster reconfiguration utilizing the skew handling mechanism. Autonomous disks adopt a multi-phase synchronization protocol with a dynamic coordinator for reconfiguration, apart from data migration. They allow the usual operations to be accepted during reconfiguration. We also report preliminary results of our experimental system. They indicate the synchronization cost is adequately acceptable.