Creating a snapshot based on a marker transferred from a first storage system to a second storage system

A storage system comprising:

• a first storage system including:
• a first volume storing data sent from a computer;
• a first memory;
• and
• a first processor which stores data sent from the computer in the first volume;
• a second storage system including:
• a second volume;
• a third volume;
• a second memory;
• and
• a second processor which stores the data sent from the first storage system in the second volume;
• wherein the first processor transfers the data stored in the first volume in the first storage system to the second storage system, and the second processor stores the data in the second volume;
• and
• wherein in executing a snapshot, the second processor checks and waits until a local copy control flag of the data that is stored in the second data area, is a predetermined value, before executing a snapshot of the data that is stored in the second data area, in the third storage volume.

A snapshot method carried out in a storage system including:

• a first storage system including:
• a first volume which includes a first data area storing data sent from a computer;
• and
• a first processor which stores data sent from the computer in the first volume;
• a second storage system including:
• a second volume which includes a second data area;
• a third volume;
• and
• a second processor which is configured to store data sent from the first storage system in the second volume;
• the snapshot method comprising operations of:
• the first processor transferring the data stored in the first data area of the first volume in the first storage system, to the second storage system, and the second processor stores the data in the second data area of the second volume;
• and
• the second processor, in executing a snapshot, checks and waits until a local copy control flag of the data that is stored in the second data area, is a predetermined value, before executing the snapshot.

A snapshot method carried out in a storage system including:

• a first storage system including:
• a first volume storing data sent from a computer;
• a first memory;
• and
• a first processor which stores data sent from the computer in the first volume;
• a second storage system including:
• a second volume;
• a third volume;
• a second memory;
• and
• a second processor which stores the data sent from the first storage system in the second volume;
• the snapshot method comprising operations of:
• the first processor transferring the data stored in the first volume in the first storage system to the second storage system, and the second processor stores the data in the second volume;
• and
• wherein in executing a snapshot, the second processor checks and waits until a local copy control flag of the data that is stored in the second data area, is a predetermined value, before executing a snapshot of the data that is stored in the second data area, in the third storage volume.