Arrangement for recovery of data by network nodes based on retrieval of encoded data distributed among the network nodes

• US 8,381,024 B2
• Filed: 12/22/2011
• Issued: 02/19/2013
• Est. Priority Date: 06/03/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Turner, Bryan C., Toebes, John, Walker, Douglas Jay
• Primary Examiner(s): Wilson, Yolanda L
• Application Number:
  US13/334,930
• Publication Number:
  US 20120096312A1
• Time in Patent Office: 425 Days
• Field of Search: None
• US Class Current: 714/6.2
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: G06F 2211/1057 Parity-multiple bits-RAID6, i.e. RAID 6 implementations
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• 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: H04L 69/14 Multichannel or multilink protocols
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06
• CPC Class Codes: H04Q 2213/13034 A/D conversion, code compression/expansion
• CPC Class Codes: H04Q 2213/13174 Data transmission, file transfer
• CPC Class Codes: H04Q 2213/13215 Code checking, CRC

Abstract

Distributed data, having been stored in a distributed storage system as a collection of distributed data elements, is recovered based on connection of multiple user nodes, each user node having stored selected distributed data elements as a corresponding portion of the distributed data during replication of the distributed data elements throughout the distributed storage system. Each distributed data element is identifiable by a corresponding unique object identifier (OID). Each user node includes a discovery resource for discovering reachable user nodes, a local cache configured for identifying at least the corresponding portion of the distributed data based on the respective OIDs, and an identification service module configured for resolving a data object to a corresponding OID, via the corresponding local cache, or based on sending a query to the reachable user nodes. Hence, user nodes can recover distributed data based on exchanging resolution information and OID information.

Claims

1. A method comprising:

connecting a first user computer to a second user computer via a data link; and

the first user computer establishing a recovered data storage system with the second user computer based on a determined unavailability of a distributed storage system having multiple storage locations, the establishing including;

identifying a first group of stored data elements to the second user computer, the first group of stored data elements having been stored in the first user computer based on replication thereof throughout the distributed storage system to a first group of the multiple storage locations including the first user computer, and

receiving from the second user computer an identification of a second group of stored data elements having been stored in the second user computer based on the replication thereof throughout the distributed storage system to a second group of the multiple storage locations including the second user computer, the recovered data storage system based on the first and second groups of stored data elements, wherein at least one of the first user computer or the second user computer is a portable computer.

2. The method of claim 1, wherein each of the stored data elements in the first group and the second group of stored data elements has a corresponding unique object identifier having been assigned by the distributed storage system and that is independent of any storage address on any storage medium, at least one of the stored data elements being a data file having been replicated by distributed storage system among at least two of the multiple storage locations.

3. The method of claim 2, wherein the establishing includes the first user computer sending the unique object identifiers of at least a portion of the first group of stored data elements to the second user computer.

4. The method of claim 3, wherein the establishing further includes the first user computer receiving the unique object identifiers of at least a portion of the second group of stored data elements from the second user computer.

5. The method of claim 2, wherein the identifying includes:

receiving from the second user computer a query specifying a name for one of the stored data elements of the first group; and

resolving the name based on supplying to the second user computer at least one of the stored data elements of the first group, or the corresponding unique object identifier assigned to the one stored data element of the first group by the distributed storage system.

6. The method of claim 2, further comprising recovering a data file from selected stored data elements of the recovered data storage system based on performing Reed-Solomon decoding.

7. The method of claim 1, wherein the identifying includes:

receiving from the second user computer a query specifying a name for one of the stored data elements of the first group; and

resolving the name based on supplying to the second user computer at least one of the one stored data element of the first group, or a corresponding unique object identifier assigned to the one stored data element of the first group by the distributed storage system, the unique object identifier independent of any storage address on any storage medium, the one stored data element being a data file having been replicated by distributed storage system among at least two of the multiple storage locations.

8. The method of claim 1, further comprising recovering a data file from selected stored data elements of the recovered data storage system based on performing Reed-Solomon decoding.

9. A user computer comprising:

a data storage medium configured for storing a first group of stored data elements based on communication by the user computer with a distributed storage system having replicated the first group of stored data elements to a first group of multiple storage locations in the distributed storage system, the first group of multiple storage locations including the user computer; and

circuitry configured for establishing a recovered data storage system with a second user computer based on a determined unavailability of a distributed storage system, the circuitry configured for identifying the first group of stored data elements to the second user computer, and receiving from the second user computer an identification of a second group of stored data elements having been stored in the second user computer based on the replication thereof by the distributed storage system to a second group of the multiple storage locations including the second user computer, the recovered data storage system based on the first and second groups of stored data elements, wherein at least one of the user computer or the second user computer is a portable computer.

10. The user computer of claim 9, wherein each of the stored data elements in the first group and the second group of stored data elements has a corresponding unique object identifier having been assigned by the distributed storage system and that is independent of any storage address on any storage medium, at least one of the stored data elements being a data file having been replicated by distributed storage system among at least two of the multiple storage locations.

11. The user computer of claim 10, wherein the circuitry is configured for sending the unique object identifiers of at least a portion of the first group of stored data elements to the second user computer.

12. The user computer of claim 11, wherein the circuitry is configured for receiving the unique object identifiers of at least a portion of the second group of stored data elements from the second user computer.

13. The user computer of claim 10, wherein:

the circuitry is configured for receiving from the second user computer a query specifying a name for one of the stored data elements of the first group;

the circuitry configured for resolving the name based on supplying to the second user computer at least one of the stored data elements of the first group, or the corresponding unique object identifier assigned to the one stored data element of the first group by the distributed storage system.

14. The user computer of claim 10, wherein the circuitry is configured for recovering a data file from selected stored data elements of the recovered data storage system based on performing Reed-Solomon decoding.

15. The user computer of claim 9, wherein:

the circuitry is configured for receiving from the second user computer a query specifying a name for one of the stored data elements of the first group;

the circuitry configured for resolving the name based on supplying to the second user computer at least one of the one stored data element of the first group, or a corresponding unique object identifier assigned to the one stored data element of the first group by the distributed storage system, the unique object identifier independent of any storage address on any storage medium, the one stored data element being a data file having been replicated by distributed storage system among at least two of the multiple storage locations.

16. The user computer of claim 9, wherein the circuitry is configured for recovering a data file from selected stored data elements of the recovered data storage system based on performing Reed-Solomon decoding.

17. A non-transitory computer readable medium having stored thereon sequences of instructions for execution by a first user computer, the sequences of instructions including instructions for:

connecting the first user computer to a second user computer via a data link; and

the first user computer establishing a recovered data storage system with the second user computer based on a determined unavailability of a distributed storage system having multiple storage locations, the establishing including;

identifying a first group of stored data elements to the second user computer, the first group of stored data elements having been stored in the first user computer based on replication thereof throughout the distributed storage system to a first group of the multiple storage locations including the first user computer, and

receiving from the second user computer an identification of a second group of stored data elements having been stored in the second user computer based on the replication thereof throughout the distributed storage system to a second group of the multiple storage locations including the second user computer, the recovered data storage system based on the first and second groups of stored data elements, wherein at least one of the first user computer or the second user computer is a portable computer.

18. The medium of claim 17, wherein each of the stored data elements in the first group and the second group of stored data elements has a corresponding unique object identifier having been assigned by the distributed storage system and that is independent of any storage address on any storage medium, at least one of the stored data elements being a data file having been replicated by distributed storage system among at least two of the multiple storage locations.

19. The medium of claim 17, wherein the identifying includes:

receiving from the second user computer a query specifying a name for one of the stored data elements of the first group; and

resolving the name based on supplying to the second user computer at least one of the one stored data element of the first group, or a corresponding unique object identifier assigned to the one stored data element of the first group by the distributed storage system, the unique object identifier independent of any storage address on any storage medium, the one stored data element being a data file having been replicated by distributed storage system among at least two of the multiple storage locations.

20. The medium of claim 17, further comprising instructions for recovering a data file from selected stored data elements of the recovered data storage system based on performing Reed-Solomon decoding.