Storage system managing data through a wide area network

• US 7,441,029 B2
• Filed: 04/18/2002
• Issued: 10/21/2008
• Est. Priority Date: 02/28/2002
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Kitamura, Manabu, Kano, Yoshiki, Takamoto, Kenichi, Iwamura, Takashige
• Primary Examiner(s): Jaroenchonwanit; Bunjob
• Assistant Examiner(s): DOAN, DUYEN MY
• Application Number:
  US10/124,401
• Publication Number:
  US 20030163568A1
• Time in Patent Office: 2,378 Days
• Field of Search: 709217-219, 707/2, 707/10, 707/205, 711/114, 711/156, 711/163
• US Class Current: 709/225
• CPC Class Codes: G06F 3/0622 in relation to access
• CPC Class Codes: G06F 3/0637 Permissions
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: H04L 63/10 for controlling access to devices or network resources
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99956 File allocation

Abstract

In a storage system, a server apparatus and a storage apparatus are provided, while the server apparatus is connected via a LAN to one, or plural sets of computers so as to accept an access request of file data issued from the computers, whereas the storage apparatus is connected via a wide area network to the server apparatus so as to store thereinto the file data. A communication between the computers and the server apparatus is carried out by employing a network file protocol, whereas a communication between the server apparatus and the storage apparatus is performed by employing a block device protocol. The server apparatus and the storage apparatus are connected via the respective security protecting apparatus to the wide area network.

Claims

1. A storage system comprising:

a first storage apparatus providing a first logical unit for storing file data in a block-based format;

a first server able to access a local second logical unit, said first server configured to transfer the file data from the local second logical unit over a wide area network to the first logical unit to make the file data available for sharing;

a management server for holding both a storage location of the file data stored in said first logical unit of said first storage apparatus and management information used to manage access to said file data in said first logical unit, said management information being transferred from said first server to said management server in conjunction with the transfer of the file data to the first logical unit, said management information identifying the file data available for sharing with other servers and the other servers allowed to share the file data; and

a first computer in communication with a second server through a local area network, said second server being configured to accept a first file-based operation request directed to the file data available for sharing via the local area network from the first computer, and send by way of the wide area network a corresponding second file-based operation request to said management server to access said file data in said first logical unit in said first storage apparatus;

wherein said management server, upon determining from said management information transferred from said first server that said second server is one of said other servers permitted to access said file data available for sharing on said first logical unit, establishes a communication path over said wide area network with said second server;

wherein when said first server and said second server are sharing said file data and are storing any of said file data as buffered data at said first server or said second server, management server requests said first server and said second server to write the buffered data into said first storage apparatus;

wherein said file data available for sharing contained within said first logical unit is accessed by said management server using a block-based protocol in response to said second file-based operation request;

wherein said management server responds to said second server using a file-based operation response, wherein said file data is shared by said first server and said second server through said wide area network.

2. A storage system as claimed in claim 1, further comprising a second storage apparatus connected to said second server, said second server including a file information for determining whether the first file-based operation request pertains to said shared first logical unit managed by said management server in said first storage apparatus, or to a third logical unit managed by said second server in said second storage apparatus.

3. A storage system as claimed in claim 2, further comprising a third storage apparatus in communication with said first server, said local second logical unit being maintained by said third storage apparatus, wherein said first server is configured to copy said file data from said third storage apparatus to said first logical unit, said first server further being configured to copy metadata for said file data to said first logical unit.

4. A storage system as claimed in claim 2, wherein said first and second servers are connected via respective first and second security protection apparatuses over the wide area network to a third security protection apparatus connected to said first storage apparatus and said management server, whereby communications over said wide area network between said first and second servers, said management server and said first storage apparatus are encrypted.

5. A storage system comprising:

a first storage apparatus, said first storage apparatus including a first logical unit;

a first server able to access a local second logical unit, said first server configured to transfer file data from the local second logical unit over a wide area network for storage in the first logical unit to make the file data available for sharing over the wide area network;

a second server connected to a computer through a local area network and connected to said first storage apparatus via the wide area network, said second server accepting a first file-based operation request from the computer via the local area network for targeting the file data in said first logical unit in said first storage apparatus; and

a management server connected via said wide area network to said first server apparatus and said second server apparatus, said management server storing both a storage position of the file data stored in the first logical unit in the first storage apparatus and management information for managing access to the file data, said management server receiving said management information from said first server in conjunction with the transfer of the file data to the first logical unit, said management information identifying other servers permitted to share the file data;

wherein said management server, upon determining from said management information that said second server is one of said other servers permitted to access said first logical unit, establishes a communication path over said wide area network with the second server;

wherein said second server is configured to send a second file-based operation request to said management server corresponding to said first file-based operation request, and said file data contained within said first logical unit is accessed by said management server using a block-based protocol in response to said second file-based operation request;

wherein when said first server and said second server actively share said file data and store any of said file data as buffered data at said first server or said second server, management server requests said first server and said second server to write the buffered data into said first storage apparatus;

wherein said file data contained within said first logical unit is shared by said first server and said second server through said wide area network.

6. A storage system as claimed in claim 5, further comprising:

a second storage apparatus locally connected to said second server, said second server including a file information for determining whether the first file-based operation request pertains to said first logical unit managed by said management server in said first storage apparatus, or to a third logical unit managed by said second server in said second storage apparatus.

7. A storage system as claimed in claim 6 further comprising a third storage apparatus in communication with said first server, said local second logical unit being maintained by said third storage apparatus, wherein said first server is configured to copy said file data from said third storage apparatus to said first logical unit, said first server further being configured to copy metadata for said file data to said first logical unit.

8. A storage system as claimed in claim 5 wherein:

said management server and said first storage apparatus are connected to a first security protection apparatus which communicates over said wide area network with a second security protection apparatus connected to said second server, whereby communications over said wide area network between said second server and said management server and said first storage apparatus are encrypted.

9. A storage system as claimed in claim 5 wherein:

said first storage apparatus comprises a disk apparatus comprising logical units using iSCSI protocol as a block device protocol, and

wherein said management server determines block positional information indicative of a range of file data to be read out by referring to i-node information maintained by said management server to enable access to the file data in the first logical unit after said management server takes over management of the file data in the first logical unit.

10. A storage system comprising:

a first storage apparatus, said first storage apparatus including a first logical unit;

a second storage apparatus for storing first file data in a second logical unit;

a first server connected locally to said second storage apparatus, said first server holding storage location information of the first file data in said second logical unit in said second storage apparatus and connected via a wide area network to said first storage apparatus;

a management server connected via said wide area network to said first server apparatus, said first server apparatus sending to said management server said first file data for storage in said first logical unit and also sending to said management server in conjunction with said first file data management information for said first file data, said management information identifying other servers allowed to share the first file data, whereby management of said first file data is transferred to said management server; and

a second server connected via said wide area network to said management server, said second server being one of said other servers allowed to share said first file data, and being configured to send to said management server a file-based operation request targeting said first file data on said first logical unit, said file-based operation request being received from a computer in communication with said second server;

wherein said management server, upon determining from said management information transferred from said first server that said second server is permitted to access said first file data on said first logical unit, establishes a communication path over said wide area network with the second server;

wherein said management server is configured to receive said file-based operation request from said second server, and access said file data contained within said first logical unit using a block-based protocol in response to said file-based operation request;

wherein when said first server and said second server actively share said file data and store any of said file data as buffered data at said first server or said second server, management server requests said first server and said second server to write the buffered data into said first storage apparatus;

wherein said file data contained within said first logical unit is shared by said first server and said second server through said wide area network.

11. A storage system as claimed in claim 10, wherein said first server is connected to said wide area network via a first security protection apparatus, said second server is connected to said wide area network via a second security protection apparatus, and said management server and said first storage apparatus are connected to said wide area network via a third security protection apparatus, whereby communications over said wide area network between said first and second servers, said management server and said first storage apparatus are encrypted.

12. A storage system as claimed in claim 10, wherein said first storage apparatus comprises a disk apparatus comprising logical units using iSCSI protocol as a block device protocol, and

wherein said management server determines block positional information indicative of a range of file data to be read out by referring to i-node information maintained by said management server to enable access to the file data in the first logical unit after said management server takes over management of the file data in to the first logical unit.