A server system includes an origin server acting as a source of deployment and at least one target server acting as a destination of deployment. The origin server further includes a virtual machine implementing an execution-facilitating process for facilitating the target server to deploy a predetermined program in an executable condition, and a migration part configured to migrate the virtual machine to the target server. After migration of the virtual machine from the origin server to the target server, the virtual machine carries out an execution-facilitating process for facilitating the origin server to deploy a predetermined program in an executable condition at least one time. This eliminates the necessity of providing a specific server dedicated to the execution-facilitating process, thus reducing the number of servers subjected to execution-facilitating processes.