The active server A101 notifies its own operating status to the administration server 106, and the administration server 106 acquires a snapshot and copies a disk according to the policy established by a user. The attachment mechanism may be configured to be deactuated, and the fasteners simultaneously moved from a deployed position to an undeployed position, allowing removal or repositioning of the medical device. A recess formed in the shaft extends from the first end surface toward the trailing end of the shaft, forms a recess wall and terminates in a second end surface that is obliquely inclined relative to the first end surface and the longitudinal axis.