Remote copy system

• US 20050125618A1
• Filed: 12/03/2004
• Published: 06/09/2005
• Est. Priority Date: 12/03/2003
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ninose, Kenta, Arakawa, Hiroshi, Hirakawa, Yusuke, Asaka, Yoshihiro
• Granted Patent: US 7,293,050 B2
• Time in Patent Office: Days
• US Class Current: 711/162
• CPC Class Codes: G06F 11/2058 using more than 2 mirrored copies
• CPC Class Codes: G06F 11/2064 while ensuring consistency
• CPC Class Codes: G06F 11/2071 using a plurality of controllers
• CPC Class Codes: G06F 11/2074 Asynchronous techniques
• CPC Class Codes: G06F 11/2082 Data synchronisation
• CPC Class Codes: G06F 2201/82 Solving problems relating to consistency ensuring consistency in mirrored systems G06F11/2064
• CPC Class Codes: G06F 2201/835 Timestamp
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

In a system in which data employed by a computer is stored in a storage system, the storage system transfers this data to another storage system and a copy of the data is maintained in the other storage system, consistency of the copy is maintained even in the case of data written to the storage system by a computer, to which a write time is not applied. A source storage system, when a write time is applied to a write request, records the write time and applies this write time to the received write data and, when no write time is applied, applies the recorded write time to the received write data and transfers the write data with this write time applied thereto, to another storage system. The target storage system stores the write data in a logical volume in the target storage system in accordance with the write time.

Claims

1-20. -20. (canceled)

21. A remote copy system comprising:

plural first storage systems, each comprising

one or a plurality of first logical volumes, each storing data written from a host computer,

a first memory, and

a first control section executing a write process based on a write request from the host computer, wherein each first control section is configured to receive a write request from the host computer, store write data received from the host computer to the first memory, send a completion report to the host computer, and after sending the completion report, transmit write data stored in the first memory to a second storage system; and

one or a plurality of second storage systems, each comprising

one or a plurality of second logical volumes, each storing copy data of data stored in a first logical volume,

a second memory, and

a second control section executing a write process to the one or plurality of second logical volumes, wherein each second control section is configured to receive write data from a first control section and store the received write data to a second memory;

wherein

a marker ID, which is a number that is common across all participating first storage systems, is provided with each first storage system from the host computer,

each first control section is configured to transmit the provided marker ID to a second storage system, and

each second control section is configured to store write data, which is stored in the second memory to a second logical volume according to the received marker ID.

22. A remote copy system according to claim 21, wherein

each second control section is configured to store write data, which is received by a first storage system before the marker ID is provided with the first storage system.

23. A remote copy system according to claim 22, wherein

each first control section is configured to transmit a marker including the marker ID to a second storage system, and

the marker is used for specifying write data, which is received by a first storage system before the marker ID is provided with the first storage system.

24. A remote copy system according to claim 21, wherein

each first control section is configured to transmit a marker including the marker ID to a second storage system, and

the marker is used for specifying a set of data, which is stored in the second memory and can be stored in a second logical volume by each second storage system.

25. A remote copy system comprising:

plural first storage systems, each comprising

one or a plurality of first logical volumes, each storing data written from a host computer,

a first memory, and

a first control section executing a write process based on a write request from the host computer, wherein each first control section is configured to receive a write request from the host computer, store write data received from the host computer to the first memory, send a completion report to the host computer, and after sending the completion report, transmit write data stored in the first memory to a second storage system;

one or a plurality of second storage systems each comprising

one or a plurality of second logical volumes, each storing copy data of data stored in a first logical volume,

a second memory, and

a second control section executing a write process to the one or plurality of second logical volumes, wherein each second control section is configured to receive write data from a first control section and store the received write data to the second memory; and

a first management section, which is configured to issue a deferment instruction to each first control section of the plural first storage systems, wherein

each first control section is configured to defer a write process according to the deferment instruction received from the first management section, and transmit a marker to a second storage system, and

each second control section is configured to store write data from the second memory to a second logical volume according to a marker received from a first control section.

26. A remote copy system according to claim 25, wherein

the marker is used for specifying a set of write data which can be stored from a second memory to a second logical volume.

27. A remote copy system according to claim 26, wherein

the marker is used by a second control section for specifying a set of write data, which is received by a first storage system before the first storage system receives the deferment instruction.

28. A remote copy system according to claim 25, wherein

the first management section is further configured to check whether each first control section has deferred a write process or not, and issue a trigger to each first control section, and

each first control section is further configured to prepare to transmit a marker to a second storage system according to the received trigger.

29. A remote copy system according to claim 28, wherein

each first control section indicates ready status to the first management section, and

the first management section checks whether each first control section has deferred a write process or not based on the ready status indicated by each first control section.

30. A remote copy system according to claim 28, wherein

the trigger is a marker create instruction, based on which each first control section creates a marker to be transmitted to a second storage system, and

the first management section is further configured to check whether each first control section has created a marker or not, and issue a restart instruction to each first control section to restart a write process in the plural first storage systems after all of the plural first storage systems have created a marker based on the marker create instruction.

31. A remote copy system according to claim 25, wherein

each second control section is further configured to acquire a snapshot of the second logical volume, in which write data received by a first storage system is stored before the first storage system receives the deferment instruction.

32. A remote copy system according to claim 25, wherein

the first management section is included in the host computer coupled to one of the plural first storage systems.

33. A remote copy system according to claim 25, wherein

the first management section is included in one of the plural first storage systems.

34. A remote copy system according to claim 25, comprising:

plural second storage systems; and

a second management section which is configured to issue a storing instruction to each second control section, wherein

each second control section of the plural second storage systems is configured to store write data, which is received by a first storage system before the first storage system receives the deferment instruction, from the second memory to a second logical volume according to the storing instruction received from the second management section.

35. A remote copy system according to claim 34, wherein

the second management section is further configured to issue a snapshot instruction to each second control section, and

each second control section is configured to acquire a snapshot of the second logical volume according to the snapshot instruction received from the second management section.

36. A remote copy system according to claim 34, wherein

the second management section is included in the host computer coupled to one of the plural second storage systems.

37. A remote copy system according to claim 34, wherein

the second management section is included in one of the plural second storage systems.

38. A remote copy system comprising:

one or a plurality of first storage systems, each said first storage system comprising

one or a plurality of first logical volumes, each said first logical volume storing write data from a host computer,

a first memory, and

a first control section executing a write process based on a write request from the host computer, wherein each first control section is configured to receive a write request from the host computer, store write data received from the host computer to the first memory, send a completion report to the host computer, and transmit write data stored in the first memory to a second storage system; and

one or a plurality of second storage systems, each comprising

one or a plurality of second logical volumes, each storing copy data of data stored in a first logical volume,

a second memory, and

a second control section executing a write process to the one or a plurality of second logical volumes, wherein each second control section is configured to receive write data from a first control section and store the received write data to a second memory;

wherein

a marker data that is common across all participating first storage systems is provided to each participating first storage system,

each first control section is configured to transmit the provided marker data to a second storage system, and

each second control section is configured to store write data, which is stored in the second memory to a second logical volume according to the received marker data.

39. A remote copy system according to claim 38, wherein

each second control section is configured to store write data, which is received by a first storage system before the marker data is provided to the first storage system.

40. A remote copy system according to claim 38, wherein

each first control section is configured to transmit a marker including the marker data to a second storage system, and

the marker is used for specifying write data, which is received by a first storage system before the marker data is provided to the first storage system.

41. A remote copy system according to claim 38, wherein

each first control section is configured to transmit a marker including the marker data to a second storage system, and

the marker is used for specifying a set of data, which is stored in the second memory and can be stored in a second logical volume by each second storage system.