To inhibit changing of a distributed OS or an application at virtual machine execution time.

A server device 100 comprises: virtual machine image generation means 102 which generates a virtual machine image including a disk image area which includes a data writing inhibited area and a user data disk image area; disk map generation means 106 which generates a disk map capable of specifying the data writing inhibited area; and virtual machine image distribution means 103 which distributes the virtual machine image generated by the virtual machine image generation means 102 and the disk map generated by the disk map generation means 106.