Storage unit, installation method thereof and installation program therefor

• US 20040143832A1
• Filed: 08/08/2003
• Published: 07/22/2004
• Est. Priority Date: 01/16/2003
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Satoyama, Ai, Yamamoto, Yasutomo, Ohno, Hiroshi, Eguchi, Yoshiaki
• Granted Patent: US 7,177,991 B2
• Time in Patent Office: Days
• US Class Current: 717/174
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• 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 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0632 by initialisation or re-initialisation of storage systems
• CPC Class Codes: G06F 3/0637 Permissions
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

A new storage unit is installed such that installation costs are suppressed and functions of the new storage unit can be utilized sufficiently. An access right is changed such that the new storage unit (second storage unit) can access an existing first storage unit (S502). A logical device relating to a storage device of the first storage unit is assigned to a logical device of the second storage unit (S503). Path definition and device recognition in a host computer are performed such that the host computer can access the assigned logical device of the second storage unit (S504, 505). Input-output setting of the host computer is changed such that processing of an input-output from the host computer to the device of the first storage unit is requested to the second storage unit (S506).

Claims

1. A storage unit installation method for newly installing a second storage unit having one or more storage devices into a computer system comprising a first storage unit having one or more storage devices and a host computer accessing said first storage unit, wherein:

said second storage unit is connected with said host computer and said first storage unit in such a way that input and output of information are possible;

access right setting of said first storage unit is changed such that the second storage unit can access the first storage unit;

a logical device (hereinafter, referred to as a first logical device) relating to said one or more storage devices of the first storage unit is assigned to a logical device (hereinafter, referred to as a second logical device) of the second storage unit;

path definition with respect to said second logical device and device recognition in said host computer are performed such that the host computer can access the second logical device of the second storage unit; and

input-output setting of said host computer is changed such that said second storage unit is requested to processing of input-output from said host computer to said one or more storage devices of said first storage unit.

2. The storage unit installation method according to claim 1, wherein:

the access right setting of said first storage unit is changed such that processing of input-output from said host computer to said one or more storage device of said first storage unit is inhibited.

3. The storage unit installation method according to one of claims 1 and 2, wherein:

in a state where said first logical device of said first storage unit is made to be seen as said second logical device of said second storage unit, from said host computer;

out of data stored in said one or more storage device of said first storage unit, a part or all of the data are migrated to said one or more storage devices of said second storage unit; and

after migration of said part or all of the data, an input-output request relating to the migrated data from said host computer to said second logical device of said second storage unit is processed as an input-output request to said one or more storage devices of said second storage unit, to which said part or all of the data have been migrated.

4. The storage unit installation method according to claim 3, wherein:

when said second storage unit receives a read request to said second logical device from said host computer,

then, in a case where said read request relates to data that have not been migrated to said second storage unit, the second storage unit converts said read request to a read request to said first logical device, and sends the converted request to said first storage unit so as to make said first storage unit performs read processing toward said storage device related to said first logical device; and

in a case where said read request from said host computer to said second logical device relates to data that have been migrated to said second storage unit, the second storage unit performs read processing toward said storage devices of the second storage unit.

5. A storage unit installation program for making a second storage unit having one or more storage devices operate when said second storage unit is newly installed into a computer system comprising a first storage unit having one or more storage devices and a host computer accessing said first storage unit, wherein said program makes following steps executed, namely:

a logical device assignment step in which a logical device (hereinafter, referred to as a first logical device) relating to said one or more storage devices of the first storage unit is assigned to a logical device (hereinafter, referred to as a second logical device) of the second storage unit; and

a path definition step in which path definition with respect to said second logical device is performed such that said host computer can access the second logical device of the second storage unit.

6. The storage unit installation program according to claim 5, wherein said program makes following steps executed, namely:

a step in which said first storage unit is made to change access right setting of said first storage unit such that the second storage unit can access the first storage unit; and

a step in which said first storage unit is made to change the access right setting of said first storage unit such that processing of input-output from said host computer to said one or more storage devices of said first storage unit is inhibited.

7. The storage unit installation program according to claim 5, wherein:

said host computer is made to change input-output setting of said host computer such that said second storage unit is requested to process input-output from said host computer to said one or more storage devices of said first storage unit.

8. The storage unit installation program according to claim 6, wherein said program makes following steps executed, namely:

a data migration step in which out of data stored in said one or more storage devices of said first storage unit, a part or all of the data are migrated to said one or more storage devices of said second storage unit; and

an input-output request destination change step in which after migration of said part or all of the data, an input-output request relating to the migrated data from said host computer to said second logical device of said second storage unit is processed as an input-output request to said one or more storage devices of said second storage unit, to which said part or all of the data have been migrated.

9. The storage unit installation program according to claim 8, wherein said program makes following steps executed, namely:

a read request reception step in which a read request from said host computer to said second logical device is received;

a read processing instruction step in which, in a case where said read request received in said read request reception step relates to data that have not been migrated to said second storage unit, the second storage unit converts said read request to a read request to said first logical device, and sends the converted request to said first storage unit so as to make said first storage unit performs read processing toward said storage device corresponding to said first logical device; and

a read processing step in which, in a case where said read request received in said read request reception step relates to data that have been migrated to said second storage unit, read processing is performed toward said storage devices of the second storage unit.

10. The storage unit installation program according to claim 8, wherein said program makes following steps executed, namely:

a write request reception step in which a write request from said host computer to said second logical device is received; and

a write processing step in which, in a case where said write request received in said write request reception step relates to data that are in course of migration to said second storage unit, said write request is converted to a write request to said first logical device and sent to said first storage unit so as to make said first storage unit perform write processing toward said storage device corresponding to said first logical device, and write processing is performed toward said storage device of said second storage unit as a migration destination of said data.

11. The storage unit installation program according to claim 9, wherein said program makes following steps executed, namely:

a write request reception step in which a write request from said host computer to said second logical device is received; and

a write processing step in which, in a case where said write request received in said write request reception step relates to data that are in course of migration to said second storage unit, said write request is converted to a write request to said first logical device and sent to said first storage unit so as to make said first storage unit perform write processing toward said storage device corresponding to said first logical device, and write processing is performed toward said storage device of said second storage unit as a migration destination of said data.

12. The storage unit installation program according to claim 6, wherein said program makes following steps executed, namely:

an addition detection step in which addition of one or more storage devices to said second storage unit is detected;

a device definition step in which, when addition of said one or more storage devices is detected in said addition detection step, a logical device is set to said one or more storage devices;

a data migration step in which a part of data stored in said one or more storage devices of said first storage unit are migrated to said one or more storage devices of said second storage unit, to which said logical device is set in said device definition step; and

an input-output request destination change step in which, after migration of said part of data, an input-output request relating to said part of data from said host computer to said second logical device of said second storage unit is performed as an input-output request to said storage devices (of said second storage unit) to which said part of data has been migrated.

13. The storage unit installation program according to claim 8, wherein said program makes following steps executed, namely:

an addition detection step in which addition of one or more storage devices to said second storage unit is detected;

a device definition step in which, when addition of said one or more storage devices is detected in said addition detection step, a logical device is set to said one or more storage devices;

a data migration step in which a part of data stored in said one or more storage devices of said first storage unit are migrated to said one or more storage devices of said second storage unit, to which said logical device is set in said device definition step; and

an input-output request destination change step in which, after migration of said past of data, an input-output request relating to said part of data from said host computer to said second logical device of said second storage unit is performed as an input-output request to said storage devices (of said second storage unit) to which said part of data has been migrated.

14. A storage unit installation program for operating an management unit that manages each unit of a computer system, when a second storage unit is newly installed into said computer system comprising a first storage unit having one or more storage devices and a host computer accessing said first storage unit, wherein said program makes following steps executed, namely:

a step in which said first storage unit is made to change access right setting of said first storage unit such that said second storage unit can access the first storage unit;

an assignment instruction step in which said second storage unit is made to assign a logical device (hereinafter, referred to as a first logical device) relating to one or more of said storage devices of the first storage unit to a logical device (hereinafter, referred to as a second logical device) of the second storage unit;

a definition instruction step in which said second storage unit is made to perform path definition with respect to said second logical device such that said host computer can access the second logical device of the second storage unit, and said host computer is made to perform device definition;

an input-output setting change instruction step in which said host computer is made to change input-output setting of said host computer such that said second storage unit is requested to process input-output from said host computer to said one or more storage devices of said first storage unit; and

a step in which said first storage unit is made to change the access right setting of said first storage unit such that processing of input-output from said host computer to said one or more storage devices of said first storage unit is inhibited.

15. A storage unit installation program for making a host computer operate when a second storage unit is newly installed into a computer system comprising a first storage unit having one or more storage devices and said host computer accessing said first storage unit, wherein said program makes following steps executed, namely:

a change instruction reception step in which an instruction to change input-output setting of said computer is received from one of a plurality of units constituting said computer system; and

an input-output setting change step in which, when said instruction is received in said change instruction reception step, said host computer is made to change input-output setting of said host computer such that said second storage unit is requested to process input-output from said host computer to said one or more storage devices of said first storage unit.

16. A storage unit installed newly into a computer system that comprises a first storage unit having one or more storage devices and a host computer accessing said first storage unit, wherein said storage unit comprises:

one or more storage devices;

a logical device assignment means for allocating a logical device (hereinafter, referred to as a first logical device) relating to said one or more storage devices of the first storage unit to a logical device (hereinafter, referred to as a second logical device) of said storage unit installed newly; and

a path definition means for performing path definition with respect to said second logical device such that the host computer can access the second logical device of said storage unit installed newly.

17. A storage unit installed newly into a computer system that comprises a first storage unit having one or more storage devices and a host computer accessing said first storage unit, wherein said storage unit comprises:

one or more storage devices; and

an installation controller for controlling installation into said computer system;

and wherein,

said installation controller;

assigns a logical device (hereinafter, referred to as a first logical device) relating to said one or more storage devices of the first storage unit to a logical device (hereinafter, referred to as a second logical device) of said storage unit installed newly; and

performs path definition with respect to said second logical device such that the host computer can access the second logical device of said storage unit installed newly.