Storage system and method of controlling the same

• US 7,603,519 B2
• Filed: 11/02/2005
• Issued: 10/13/2009
• Est. Priority Date: 03/31/2003
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Hitachi, Ltd.
• Inventors: Ito, Ryusuki, Takeda, Takahiko, Kaiya, Keiichi
• Primary Examiner(s): Elmore; Reba I
• Application Number:
  US11/266,059
• Publication Number:
  US 20060059303A1
• Time in Patent Office: 1,441 Days
• Field of Search: 711/118, 711/148, 709/213, 709/216
• US Class Current: 711/118
• CPC Class Codes: G06F 11/2071 using a plurality of controllers
• CPC Class Codes: G06F 11/2082 Data synchronisation
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

A storage system which manages a plurality of storage control apparatus in an integrated manner is provided. An I/O request issued by a host apparatus to a second storage control apparatus is forwarded to the second storage control apparatus through a first storage control apparatus. The first storage control apparatus has management information for the second storage control apparatus, allowing a pair comprising a logical device controlled by the first storage control apparatus and a logical device controlled by the second storage control apparatus to be created. In addition, the first storage control apparatus is capable of controlling the second storage control apparatus.

Claims

1. A control method adopted by a storage system including a first storage control apparatus having a first storage device and a second storage control apparatus including a second storage device connected to the first storage control apparatus, the control method comprising:

allowing the first storage control apparatus to receive a data write or read command from a host apparatus;

determining whether the data write or read command received from the host apparatus is to be executed by a data operation involving the first storage device or a data operation involving the second storage device based upon management information in the first storage control apparatus; and

writing data into the first storage device or the second storage device or reading out data from the first storage device or the second storage device based upon the step of determining.