Computer system

A data copying control method that stores date on multiple storage systems as executing prescribed work processing, the method comprising the steps of:

• providing a computer system, wherein the computer system comprises a primary storage system that is connected to a first computer, a secondary storage system that is connected to a second computer, and an intermediate storage system that is connected to said primary and secondary storage systems;
• copying the data stored in said primary storage system into said intermediate storage system via synchronous copying for storage therein and replaying the data copied into said intermediate storage system to said secondary storage system via asynchronous copying for storage therein, while said first computer is executing said work processing;
• and
• copying ultimately the data stored said secondary storage system to said primary storage system via asynchronous copying for storage therein, while said second computer is executing said work processing.

A computer system storing date on multiple storage systems, said computer system comprising:

• a primary storage system that is connected to a first computer that executes prescribed work processing and stores data used when the first computer is executing said work processing;
• a secondary storage system that is connected to a-second computer that executes said work processing in place of said first computer and stores data used when said second computer is executing said work processing;
• an intermediate storage system that is connected to said primary and secondary storage systems and stores received data,
• a synchronous copy device that is incorporated in said primary storage system, and that copies the data stored in the primary storage system into said intermediate storage system via synchronous copying for storage therein and copies the copied data into said intermediate storage system to said secondary storage system via asynchronous copying for storage therein, as executing said work processing by said first computer;
• and
• an asynchronous copy device that is incorporated in said secondary storage system, and that copies the data stored in the secondary storage system ultimately to said primary storage system via asynchronous copying for storage therein, as executing said work processing by said second computer.