Computer system, remote copy method and first computer

• US 20090193207A1
• Filed: 03/17/2008
• Published: 07/30/2009
• Est. Priority Date: 01/29/2008
• Status: Abandoned Application

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Suzuki, Hidenori, Ogata, Youko
• Application Number:
  US12/076,329
• Publication Number:
  US 20090193207A1
• Time in Patent Office: Days
• US Class Current: 711/162
• CPC Class Codes: G06F 3/0611 in relation to response time
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0656 Data buffering arrangements
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

In a computer system of the present invention, the logical volume of a network storage device can be exclusively shared by a plurality of computers. A first computer, upon receiving a remote copy request, writes a remote copy target file to a logical volume inside a shared storage device, and stores location management information showing the write-destination or the like of the file in a memory device. A second computer, upon receiving an access request, acquires the logical volume lock from the first computer. The second computer mounts the logical volume, and executes the desired processing. Furthermore, the second computer reads out the file from the logical volume based on the location management information.

Claims

1. A computer system, in which a first computer, a second computer and a shared storage device are communicably connected via a communication network, wherein

the shared storage device comprises at least one logical volume that is shared by the first computer and the second computer,

the first computer comprises a first storage device, and a first controller for controlling the input/output of data to/from the first storage device, and permission to use the shared storage device,

the second computer comprises a second storage device, and a second controller for controlling the input/output of data to/from the second storage device,

the first controller, upon receiving a remote copy request to remote copy data from the first storage device to the second storage device via the logical volume, transfers remote copy target data specified by the remote copy request from the first storage device and stores the data in the logical volume, and, stores location management information, which shows that the remote copy target data is stored in a prescribed location in the logical volume, in the first storage device, and

the second controller queries the first controller in accordance with an inputted access request for permission to use the logical volume, acquires the location management information from the first storage device, and transfers the remote copy target data stored in the logical volume to the second storage device from the logical volume.

2. The computer system according to claim 1, wherein the access request inputted to the second computer is at least any one of a request to read from the logical volume, a request to write to the logical volume, a request to check the logical volume, or a request to delete the data inside the logical volume.

3. The computer system according to claim 1, wherein, when the access request inputted to the second computer shows that remote copy is prohibited, the second controller does not transfer the remote copy target data from the logical volume to the second storage device.

4. The computer system according to claim 1, wherein the second controller, upon receiving permission from the first controller to use the logical volume, accesses the first storage device and determines whether or not the location management information is stored in the first storage device, and when the location management information is stored in the first storage device, transfers all the remote copy target data specified by the location management information from the logical volume to the second storage device.

5. The computer system according to claim 1, wherein the first storage device comprises a first memory device, and a first auxiliary storage device with a storage capacity that is larger than the first memory device, and

the location management information is stored in the first memory device.

6. The computer system according to claim 1, wherein the first controller comprises a cache function for temporarily storing data read out from the logical volume, and the cache function controls a temporary storage destination of the data in accordance with a type of the data read out from the logical volume.

7. The computer system according to claim 6, wherein, when the data stored in the logical volume is changed, the first controller destroys cache data corresponding to the data to be changed, and, when data stored in the logical volume is read out, stores cache data of the read-out data.

8. The computer system according to claim 7, wherein, when the cache data is created, the first controller creates and stores verification information comprising a location inside the logical volume of the data read out from the logical volume, and a mount point when mounting the data.

9. The computer system according to claim 6, wherein the first storage device comprises a first memory device with a relatively small storage capacity, and a first auxiliary storage device with a relatively larger storage capacity than the first memory device, and

the first controller temporarily stores data read out from the logical volume in the first memory device when the data has a relatively small data size, and stores data read out from the logical volume in the first auxiliary storage device when the data has a relatively large data size.

10. The computer system according to claim 6, wherein the first storage device comprises a first memory device with a relatively small storage capacity, and a first auxiliary storage device with a relatively larger storage capacity than the first memory device, and

the first controller:

(1) temporarily stores data read out from the logical volume in the first memory device when the data has a relatively small data size, and stores data read out from the logical volume in the first auxiliary storage device when the data has a relatively large data size;

(2) upon creating the cache data, creates and stores verification information comprising a location inside the logical volume of the data read out from the logical volume, and a mount point when mounting the data;

(3) when data stored in the logical volume is changed, destroys only cache data corresponding to the data to be changed, and stores the verification information as-is; and

(4) when data stored in the logical volume is read out, stores cache data of the read-out data.

11. The computer system according to claim 1, wherein the first controller stores in a wait queue a separate usage request issued while the logical volume is used, and when it becomes possible to use the logical volume, issues an indication to reboot the separate usage request stored in the wait queue.

12. The computer system according to claim 1, wherein the shared storage device is configured as a storage device that operates based on the iSCSI (Internet Small Computer System Interface).

13. A remote copy method for carrying out a remote copy from a first computer to a second computer by way of a shared storage device,

the shared storage device comprising at least one logical volume that is shared by the first computer and the second computer,

the remote copy method comprising the steps of:

the first computer receiving a remote copy request to remote copy data from a first storage device of the first computer to a second storage device via the logical volume;

the first computer transferring remote copy target data specified by the remote copy request from the first storage device and stores the data in the logical volume;

the first computer storing location management information, which shows that the remote copy target data is stored in a prescribed location in the logical volume, in the first computer;

the second computer receiving an access request related to the logical volume;

the second computer querying the first computer for permission to use the logical volume;

the first computer responding to a query from the second computer;

the second computer acquiring the location management information from the first computer upon obtaining permission to use the logical volume from the first computer; and

the second computer transferring all or a portion of the remote copy target data stored in the logical volume to the second storage device of the second computer from the logical volume.

14. A first computer, which is respectively connected to a second computer and a shared storage device via a communication network,

the shared storage device comprising at least one logical volume that is shared by the first computer and the second computer,

the first computer comprising:

a first storage device; and

a first controller for respectively controlling input/output of data to/from the first storage device, and the permission to use the shared storage device,

wherein the first controller, upon receiving a remote copy request to remote copy data from the first storage device to a second storage device of the second computer via the logical volume, transfers remote copy target data specified by the remote copy request from the first storage device and stores the data in the logical volume, and, stores location management information, which shows that the remote copy target data is stored in a prescribed location in the logical volume, in the first storage device, and

when the second computer queries for permission to use the logical volume, transfers the remote copy target data in the logical volume to the second storage device from the logical volume on the basis of the location management information.