A volume driver is provided in each server that executes a container engine. A first volume driver embeds, in a container image of a container in a first server, a volume ID (which is the ID of a volume, and is according to information acquired from a storage system with respect to the volume) of the volume associated with the container. A second volume driver searches, in the storage system, for a volume to be associated with the container based on the container image, by using the volume ID embedded in the container image outputted from the first server and inputted to the second server.