STORING RAID DATA AS ENCODED DATA SLICES IN A DISPERSED STORAGE NETWORK

• US 20110214011A1
• Filed: 12/31/2010
• Published: 09/01/2011
• Est. Priority Date: 02/27/2010
• Status: Active Grant

• Current Assignee: Pure Storage, Inc.
• Original Assignee: Cleversafe Incorporated (International Business Machines Corporation)
• Inventors: Markison, Timothy W., Grube, Gary W.
• Granted Patent: US 9,311,184 B2
• Time in Patent Office: Days
• US Class Current: 714/6.22
• CPC Class Codes: G06F 11/0727 in a storage system, e.g. in a DASD or network based storage system drivers for digital recording or reproducing units G06F3/06; circuits for error detection or correction within digital recording or reproducing units G11B20/18; 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], H04L67/1097
• CPC Class Codes: G06F 11/1076 Parity data used in redundant arrays of independent storages, e.g. in RAID systems
• CPC Class Codes: G06F 11/1092 Rebuilding, e.g. when physically replacing a failing disk
• CPC Class Codes: G06F 11/1096 Parity calculation or recalculation after configuration or reconfiguration of the system
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: G06F 3/0614 Improving the reliability of storage systems
• CPC Class Codes: G06F 3/0619 in relation to data integrity, e.g. data losses, bit errors
• CPC Class Codes: G06F 3/0631 by allocating resources to storage systems
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/065 Replication mechanisms
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 3/068 Hybrid storage device
• CPC Class Codes: G06F 3/0685 Hybrid storage combining heterogeneous device types, e.g. hierarchical storage, hybrid arrays
• CPC Class Codes: G06F 3/0689 Disk arrays, e.g. RAID, JBOD
• 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]

Abstract

A method begins by a processing module receiving data for storage and interpreting the data to identify the data as redundant array of independent disks (RAID) data. The method continues with the processing module interpreting the RAID data to identify at least one of RAID block data and RAID parity data. When the RAID data includes RAID block data and RAID parity data the method continues with the processing module encoding the RAID block data in accordance with error coding dispersal storage function parameters to produce at least one set of encoded data slices and outputting the at least one set of encoded data slices to a dispersed storage network memory.

Claims

1. A method comprises:

receiving data for storage;

interpreting the data to identify the data as redundant array of independent disks (RAID) data;

interpreting the RAID data to identify at least one of RAID block data and RAID parity data; and

when the RAID data includes RAID block data and RAID parity data;

encoding the RAID block data in accordance with error coding dispersal storage function parameters to produce at least one set of encoded data slices; and

outputting the at least one set of encoded data slices to a dispersed storage network (DSN) memory.

2. The method of claim 1, wherein the encoding the RAID block data comprises:

determining accuracy of the RAID block data based on the RAID parity data; and

when the accuracy of the RAID block data compares unfavorably to a desired accuracy, correcting the RAID block data based on the RAID parity data.

3. The method of claim 1 further comprises:

when the RAID data only includes the RAID parity data, encoding the RAID parity data in accordance with the error coding dispersal storage function parameters to produce at least one set of encoded parity slices; and

outputting the at least one set of encoded parity slices to the DSN memory.

4. The method of claim 1, wherein the receiving the data for storage comprises:

sending a request to a RAID memory device regarding the RAID data; and

receiving the RAID data from the RAID memory device.

5. The method of claim 1, wherein the encoding the RAID block data further comprises:

determining the error coding dispersal storage function parameters based on at least one of;

the RAID data, detection of the RAID block data, the RAID parity data, detection of a RAID data stripe, RAID data checksum information, a vault lookup, RAID memory configuration information, a command, a message, a predetermination, a data object name, a data object, a data object size, a data type, a data block, parity information, a user identifier (ID), RAID unit information, disk drive information, address information, memory information, a command, and a request.

6. A method comprises:

receiving data retrieval request;

interpreting the data retrieval request to identify the data retrieval request as redundant array of independent disks (RAID) data retrieval request;

retrieving at least one set of encoded data slices based on the RAID data retrieval request;

decoding the at least one set of encoded data slices in accordance with error coding dispersal storage function parameters to produce RAID data;

interpreting the RAID data to determine whether the RAID data represents a stripe of data or a stripe-block of data; and

when the RAID data represents the stripe of data;

generating RAID parity data from RAID block data of the RAID data; and

outputting the RAID block data and the RAID parity data.

7. The method of claim 6 further comprises:

when the RAID data represents the stripe-block of data, outputting the RAID data.

8. The method of claim 6, wherein the interpreting the RAID data comprises:

interpreting a header section of the RAID data to determine whether the RAID data represents the stripe of data or the stripe-block of data.

9. A computer comprises:

an interface;

a memory; and

a processing module operable to;

receive, via the interface, data for storage;

interpret the data to identify the data as redundant array of independent disks (RAID) data;

interpret the RAID data to identify at least one of RAID block data and RAID parity data; and

when the RAID data includes RAID block data and RAID parity data;

encode the RAID block data in accordance with error coding dispersal storage function parameters to produce at least one set of encoded data slices; and

output, via the interface, the at least one set of encoded data slices to a dispersed storage network (DSN) memory.

10. The computer of claim 9, wherein the processing module further functions to encode the RAID block data by:

determining accuracy of the RAID block data based on the RAID parity data; and

correcting the RAID block data based on the RAID parity data when the accuracy of the RAID block data compares unfavorably to a desired accuracy.

11. The computer of claim 9, wherein the processing module further functions to:

encode the RAID parity data in accordance with the error coding dispersal storage function parameters to produce at least one set of encoded parity slices when the RAID data only includes the RAID parity data; and

output, via the interface, the at least one set of encoded parity slices to the DSN memory.

12. The computer of claim 9, wherein the processing module functions to receive the data for storage by:

sending, via the interface, a request to a RAID memory device regarding the RAID data; and

receiving, the interface, the RAID data from the RAID memory device.

13. The computer of claim 9, wherein the processing module further functions to encode the RAID block data by:

determining the error coding dispersal storage function parameters based on at least one of;

the RAID data, detection of the RAID block data, the RAID parity data, detection of a RAID data stripe, RAID data checksum information, a vault lookup, RAID memory configuration information, a command, a message, a predetermination, a data object name, a data object, a data object size, a data type, a data block, parity information, a user identifier (ID), RAID unit information, disk drive information, address information, memory information, a command, and a request.

14. A computer comprises:

an interface;

a memory; and

a processing module operable to;

receive, via the interface, data retrieval request;

interpret the data retrieval request to identify the data retrieval request as redundant array of independent disks (RAID) data retrieval request;

retrieve, via the interface, at least one set of encoded data slices based on the RAID data retrieval request;

decode the at least one set of encoded data slices in accordance with error coding dispersal storage function parameters to produce RAID data;

interpret the RAID data to determine whether the RAID data represents a stripe of data or a stripe-block of data; and

when the RAID data represents the stripe of data;

generate RAID parity data from RAID block data of the RAID data; and

output, via the interface, the RAID block data and the RAID parity data.

15. The computer of claim 14, wherein the processing module further functions to:

output, via the interface, the RAID data when the RAID data represents the stripe-block of data.

16. The computer of claim 14, wherein the processing module interprets the RAID data by:

interpreting a header section of the RAID data to determine whether the RAID data represents the stripe of data or the stripe-block of data.