Computer system with storage system having re-configurable logical volumes

• US 6,880,058 B2
• Filed: 07/20/2001
• Issued: 04/12/2005
• Est. Priority Date: 12/07/2000
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Muraoka, Kenji, Mizuno, Yoichi, Mimatsu, Yasuyuki, Matsunami, Naoto
• Primary Examiner(s): Padmanabhan, Mano
• Assistant Examiner(s): BAKER, PAUL A
• Application Number:
  US09/910,153
• Publication Number:
  US 20020073297A1
• Time in Patent Office: 1,362 Days
• Field of Search: 711/170, 711/112, 711/114
• US Class Current: 711/170
• CPC Class Codes: G06F 11/1096 Parity calculation or recalculation after configuration or reconfiguration of the system
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD

Abstract

In order to enable an area of each logical volume to be expanded while continuously using the logical volume and to integrate separate logical volumes in a single continuous area, a storage has logical volume control means for controlling the construction of a logical volume, a logical volume number map in which logical volume construction information is described, and copy means for copying the logical volume. By allowing two or more inner logical numbers to be described per external logical number in the logical volume number map, improved flexibility in combining the logical volumes in the storage is achieved. By copying a plurality of separate logical volumes into a physical continuous area by the copy means, the logical volumes are integrated.

Claims

1. A computer system with a storage system having reconfigurable logical volumes comprising:

a plurality of computers;

a storage system operatively coupled to said computers and comprising a plurality of inner logical volumes and an LU controller said inner logical volumes; and

a management console to communicate instructions to change a logical volume configuration of said logical volumes,

said LU controller comprising an LUN map designating an association among an outer LUN, one or more inner LUNs, and a computer ID, said outer LUN designating an outer logical volume that can be accessed by one of said computers, each of said inner LUNs designating one of said inner logical volumes whereby said outer logical volume can be associated with one or more of said inner logical volumes, said computer ID designating one of said computers,

said LU controller responsive to an instruction to change said logical volume configuration by modifying said LUN map according to said instruction,

wherein prior to said LUN map being modified, a first outer LUN and a first computer ID are associated with a first inner LUN,

wherein subsequent to said LUN map being modified, said first outer LUN and first computer ID are associated with a second inner LUN different from said first inner LUN,

wherein said instruction to change a logical volume configuration includes said first inner LUN and a requested size,

wherein said LU controller is configured such that if a free storage area exists which has a size that is larger than said requested size plus the size of said inner logical volume designated by said first inner LUN, then said LU controller copies data stored in said inner logical volume designated by said first inner LUN to said free storage area, and rewrites said LUN map to correlate said free storage area with said first outer LUN, with said first computer ID, and with said second inner LUN, said second inner LUN being associated with said free storage area,

wherein said LU controller is further configured such that if said free storage area does not exist in said storage system, then said LU controller rewrites said LUN map to correlate said first outer LUN with said logical volume designated by said first inner LUN and with any free storage area in said storage system.

2. A computer system of claim 1, wherein each of said plurality of computers searches an outer logical volume by using an outer LUN.

3. A computer system of claim 1, wherein subsequent to said LUN map being modified, said first outer LUN and said first computer ID are further associated with said first inner LUN as well as said second inner LUN, wherein storage capacity of said outer logical volume designated by said first outer LUN comprises combined storage capacities of said first inner LUN and said second inner LUN.

4. A computer system of claim 3, wherein said instruction to change a logical volume configuration includes said first inner LUN and said second inner LUN.

5. A computer system comprising:

a plurality of computers; and

a storage system in data communication with said computers, said storage system comprising a plurality of logical volumes designated as inner logical volumes and a LUN map, said LUN map identifying an association among a first outer LUN, a first computer ID, and a first inner LUN, said first outer LUN designating an outer logical volume wherein a computer identified by said first computer ID can access said outer logical volume using said first outer LUN, whereby said first inner LUN is accessed when said outer logical volume is accessed,

said storage system operative to receive a LUN configuration change instruction designating said first inner LUN and a storage capacity indication,

wherein if there is a second inner LUN having a storage capacity equal to or greater than a sum of a storage capacity of said first inner LUN and said storage capacity indication, then said storage system is operative to respond to said LUN configuration change instruction by copying information stored on said first inner LUN to said second inner LUN and modifying said LUN map so that said first outer LUN and said first computer ID are associated with said second inner LUN,

wherein subsequent to said LUN configuration change instruction, said second inner LUN is accessed when said outer logical volume is accessed.