Object migration system using tape medium, object migration source storage device, and object migration destination storage device

A storage system comprising:

• a host device configured to transmit a write command and a read command;
• a first storage device that includes a first memory and a first processor coupled to the first memory;
• and
• a second storage device that includes a second memory and a second processor coupled to the second memory,
• the first processor is configured to:
• when migrating first data that indicates at least one selected from a data creation date, a data creator, a data type, a storage period, and a number of times of copies, generate dummy data whose size is a same size as a size of an object related to the first data without using data obtained by reading from a storage medium of a cartridge used for the first storage device, and
• transmit management information used to manage the object and the dummy data to the second storage device, and
• the second processor is configured to:
• store the management information in a storage unit in association with the object,
• discard the dummy data without writing the first data in a storage medium of a cartridge used for the second storage device, and
• when migration of the object is completed, cause the management information to be updated so that the management information indicates that the cartridge used for the first storage device is available for the write command and the read command from the host device.