AUTHORIZING DISTRIBUTED TASK PROCESSING IN A DISTRIBUTED STORAGE NETWORK

• US 20130232503A1
• Filed: 04/18/2013
• Published: 09/05/2013
• Est. Priority Date: 12/12/2011
• Status: Active Grant

• Current Assignee: Pure Storage, Inc.
• Original Assignee: Cleversafe Incorporated (International Business Machines Corporation)
• Inventors: Volvovski, Ilya, Resch, Jason K.
• Granted Patent: US 9,430,286 B2
• Time in Patent Office: Days
• US Class Current: 718/104
• CPC Class Codes: G06F 11/1044 with specific ECC/EDC distribution
• 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 16/2365 Ensuring data consistency and integrity
• CPC Class Codes: G06F 21/6218 to a system of files or objects, e.g. local or distributed file system or database
• CPC Class Codes: G06F 2211/1028 Distributed, i.e. distributed RAID systems with parity
• CPC Class Codes: G06F 9/50 Allocation of resources, e.g. of the central processing unit [CPU]
• CPC Class Codes: G06F 9/5083 Techniques for rebalancing the load in a distributed system
• CPC Class Codes: H03M 13/09 Error detection only, e.g. using cyclic redundancy check [CRC] codes or single parity bit
• CPC Class Codes: H03M 13/13 Linear codes
• CPC Class Codes: H03M 13/1515 Reed-Solomon codes
• 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 distributed storage (DS) processing module transmitting a set of requests to a set of DS units regarding a set of data elements and receiving a set of respective requests from the set of DS units. When the set of respective requests is in accordance with a current distributed task/data responsibility allocation period, the method continues with the DS processing module issuing a set of responses to the set of DS units. The method continues with the DS processing module receiving a set of respective responses from the set of DS units. When the set of received respective responses is in accordance with the current distributed task/data responsibility allocation period, the method continues with the DS processing module processing the set of received respective responses in accordance with the current distributed task/data responsibility allocation period to produce one of a set of results.

Claims

1. A method for execution by a set of distributed storage (DS) units, the method comprises:

transmitting, by each DS unit of the set of DS units, a set of requests to other DS units of the set of DS units, wherein a request of the set of requests includes requesting a response regarding a respective data element of a set of data elements from a respective one of the other DS units, and wherein the set of requests are generated in accordance with a current distributed task/data responsibility allocation period, wherein, collectively, the set of DS units contains a plurality of sets of data elements;

receiving, by the each DS unit, a respective request from each of the other DS units such that the each DS unit receives a set of respective requests from the other DS units;

when each of the set of respective requests is in accordance with the current distributed task/data responsibility allocation period;

generating, by the each DS unit, a response to each respective request of the set of respective requests to produce a set of responses; and

sending, by the each DS unit, the set of responses to the other DS units;

receiving, by the each DS unit, a respective response from each of the sets of responses from the other DS units such that the each DS unit receives a set of respective responses from the other DS units; and

when the set of respective responses is in accordance with the current distributed task/data responsibility allocation period, processing, by the each DS unit, the set of respective responses in accordance with the current distributed task/data responsibility allocation period to produce one of a set of results such that the set of DS units produces the set of results regarding the plurality of sets of data elements.

2. The method of claim 1, wherein the processing the set of respective responses comprises at least one of:

performing, by the each DS unit, an integrity check on data elements associated with the set of respective responses to produce the one of the set of results, wherein the set of results provides an integrity indication for the plurality of sets of data elements;

verifying, by the each DS unit, a read request based on the data elements associated with the set of respective responses to produce the one of the set of results, wherein the set of results provides a validity indication for a read operation regarding the plurality of sets of data elements; and

verifying, by the each DS unit, a write request based on the data elements associated with the set of respective responses to produce the one of the set of results, wherein the set of results provides a validity indication for a write operation regarding the plurality of sets of data elements.

3. The method of claim 1 further comprises:

when one of the set of respective requests is not in accordance with the current distributed task/data responsibility allocation period, indicating, by the each DS unit, as potentially compromised, the respective one of the other DS units corresponding to the one of the set of respective requests not in accordance with the current distributed task/data responsibility allocation period.

4. The method of claim 3 further comprises at least one of:

determining, by the each DS unit, that the one of the set of respective requests is not in accordance with the current distributed task/data responsibility allocation period when the respective one of the other DS units corresponding to the one of the set of respective requests is not an anticipated requesting DS unit in accordance with the current distributed task/data responsibility allocation period;

determining, by the each DS unit, that the one of the set of respective requests is not in accordance with the current distributed task/data responsibility allocation period when the one of the set of respective requests is not an anticipated request in accordance with the current distributed task/data responsibility allocation period; and

determining, by the each DS unit, that the one of the set of respective requests is not in accordance with the current distributed task/data responsibility allocation period when the one of the set of respective requests is a second request by the respective one of the other DS units.

5. The method of claim 1 further comprises:

when one of the set of respective responses is not in accordance with the current distributed task/data responsibility allocation period, indicating, by the each DS unit, as potentially compromised, the respective one of the other DS units corresponding to the one of the set of respective responses not in accordance with the current distributed task/data responsibility allocation period.

6. The method of claim 5 further comprises at least one of:

determining, by the each DS unit, that the one of the set of respective responses is not in accordance with the current distributed task/data responsibility allocation period when the respective one of the other DS units corresponding to the one of the set of respective responses is not an anticipated responding DS unit in accordance with the current distributed task/data responsibility allocation period;

determining, by the each DS unit, that the one of the set of respective responses is not in accordance with the current distributed task/data responsibility allocation period when the one of the set of respective responses is not an anticipated response in accordance with the current distributed task/data responsibility allocation period; and

determining, by the each DS unit, that the one of the set of respective responses is not in accordance with the current distributed task/data responsibility allocation period when the one of the set of respective responses is a second response by the respective one of the other DS units.

7. The method of claim 1, wherein the current distributed task/data responsibility allocation period comprises at least one of:

a time varying allocation of tasks among the set of DS units;

a time varying allocation of data elements to process;

a time varying allocation of permissible requests; and

a time varying allocation of permissible responses.

8. A method comprises:

receiving an encoded data slice integrity status request, wherein the encoded data slice integrity status request includes an identifier (ID) of a requesting entity and a requested dispersed storage network (DSN) address range;

determining whether the requesting entity is authorized to send the encoded data slice integrity status request in accordance with a current authorized data integrity verification allocation period;

when the requesting entity is authorized to send the encoded data slice integrity status request, determining whether the requested DSN address range is in accordance with the current authorized data integrity verification allocation period;

when the requested DSN address range is in accordance with the current authorized data integrity verification allocation period;

performing an encoded data slice integrity status evaluation operation in accordance with the encoded data slice integrity status request to produce an encoded data slice integrity status response; and

outputting the encoded data slice integrity status response to the requesting entity; and

when either the requesting entity is not authorized or the requested DSN address range is not in accordance with the current authorized data integrity verification allocation period, indicating that the requesting entity may be compromised.

9. The method of claim 8 further comprises:

after performing the encoded data slice integrity status evaluation operation, indicating that the encoded data slice integrity status evaluation operation was performed on the requested DSN address range in accordance with the current authorized data integrity verification allocation period such that a second request from the requesting entity while the current authorized data integrity verification allocation period is active would be determined to be unauthorized.

10. The method of claim 8, wherein the performing the encoded data slice integrity status evaluation operation in accordance with the encoded data slice integrity status request comprises at least one of:

when the encoded data slice integrity status request includes a slice list request, generating a list of slice names associated with the requested DSN address range to produce the encoded data slice integrity status response;

when the encoded data slice integrity status request includes a slice list digest request, generating the list of slice names associated with the requested DSN address range and generating a digest of the list of slice names to produce the encoded data slice integrity status response; and

when the encoded data slice integrity status request includes a slice integrity request;

generating at least one slice digest for at least one slice associated with the requested DSN address range;

for each slice digest of the at least one slice digest, comparing a retrieved slice digest to the slice digest to produce comparing results; and

generating the encoded data slice integrity status response to include the comparing results.

11. The method of claim 8 further comprises:

obtaining the current authorized data integrity verification allocation period from a trusted source, wherein the current authorized data integrity verification allocation period is a currently active version of one of a plurality of authorized data integrity verification allocation scenarios.

12. A distributed storage (DS) module of each DS unit of a set of DS units, the DS module comprises:

a first module, when operable within a computing device, causes the computing device to;

transmit a set of requests to other DS units of the set of DS units, wherein a request of the set of requests includes requesting a response regarding a respective data element of a set of data elements from a respective one of the other DS units, and wherein the set of requests are generated in accordance with a current distributed task/data responsibility allocation period, wherein, collectively, the set of DS units contains a plurality of sets of data elements;

a second module, when operable within the computing device, causes the computing device to;

receive a respective request from each of the other DS units to produce a set of respective requests; and

when each of the set of respective requests is in accordance with the current distributed task/data responsibility allocation period;

generate a response to each respective request of the set of respective requests to produce a set of responses; and

send the set of responses to the other DS units; and

a third module, when operable within the computing device, causes the computing device to;

receive a respective response from each of the sets of responses from the other DS units such that the each DS unit receives a set of respective responses from the other DS units; and

when the set of respective responses is in accordance with the current distributed task/data responsibility allocation period, process the set of respective responses in accordance with the current distributed task/data responsibility allocation period to produce one of a set of results such that the set of DS units produces the set of results regarding the plurality of sets of data elements.

13. The DS module of claim 12, wherein the third module functions to process the set of respective responses by at least one of:

performing an integrity check on data elements associated with the set of respective responses to produce the one of the set of results, wherein the set of results provides an integrity indication for the plurality of sets of data elements;

verifying a read request based on the data elements associated with the set of respective responses to produce the one of the set of results, wherein the set of results provides a validity indication for a read operation regarding the plurality of sets of data elements; and

verifying a write request based on the data elements associated with the set of respective responses to produce the one of the set of results, wherein the set of results provides a validity indication for a write operation regarding the plurality of sets of data elements.

14. The DS module of claim 12 further comprises:

when one of the set of respective requests is not in accordance with the current distributed task/data responsibility allocation period, the second module further functions to indicate as potentially compromised, the respective one of the other DS units corresponding to the one of the set of respective requests not in accordance with the current distributed task/data responsibility allocation period.

15. The DS module of claim 14 further comprises at least one of:

the second module further functions to determine that the one of the set of respective requests is not in accordance with the current distributed task/data responsibility allocation period when the respective one of the other DS units corresponding to the one of the set of respective requests is not an anticipated requesting DS unit in accordance with the current distributed task/data responsibility allocation period;

the second module further functions to determine that the one of the set of respective requests is not in accordance with the current distributed task/data responsibility allocation period when the one of the set of respective requests is not an anticipated request in accordance with the current distributed task/data responsibility allocation period; and

the second module further functions to determine that the one of the set of respective requests is not in accordance with the current distributed task/data responsibility allocation period when the respective one of the set of respective requests is a second request by the one of the other DS units.

16. The DS module of claim 12 further comprises:

when one of the set of respective responses is not in accordance with the current distributed task/data responsibility allocation period, the third module further functions to indicate as potentially compromised, the respective one of the other DS units corresponding to the one of the set of respective responses not in accordance with the current distributed task/data responsibility allocation period.

17. The DS module of claim 16 further comprises at least one of:

the third module further functions to determine that the one of the set of respective responses is not in accordance with the current distributed task/data responsibility allocation period when the respective one of the other DS units corresponding to the one of the set of respective responses is not an anticipated responding DS unit in accordance with the current distributed task/data responsibility allocation period;

the third module further functions to determine that the one of the set of respective responses is not in accordance with the current distributed task/data responsibility allocation period when the one of the set of respective responses is not an anticipated response in accordance with the current distributed task/data responsibility allocation period; and

the third module further functions to determine that the one of the set of respective responses is not in accordance with the current distributed task/data responsibility allocation period when the one of the set of respective responses is a second response by the respective one of the other DS units.

18. The DS module of claim 12, wherein the current distributed task/data responsibility allocation period comprises at least one of:

a time varying allocation of tasks among the set of DS units;

a time varying allocation of data elements to process;

a time varying allocation of permissible requests; and

a time varying allocation of permissible responses.

19. A dispersed storage (DS) module comprises:

a first module, when operable within a computing device, causes the computing device to;

receive an encoded data slice integrity status request, wherein the encoded data slice integrity status request includes an identifier (ID) of a requesting entity and a requested dispersed storage network (DSN) address range;

determine whether the requesting entity is authorized to send the encoded data slice integrity status request in accordance with a current authorized data integrity verification allocation period; and

when the requesting entity is authorized to send the encoded data slice integrity status request, determine whether the requested DSN address range is in accordance with the current authorized data integrity verification allocation period;

a second module, when operable within the computing device, causes the computing device to;

when the requested DSN address range is in accordance with the current authorized data integrity verification allocation period;

perform an encoded data slice integrity status evaluation operation in accordance with the encoded data slice integrity status request to produce an encoded data slice integrity status response; and

output the encoded data slice integrity status response to the requesting entity; and

a third module, when operable within the computing device, causes the computing device to;

when either the requesting entity is not authorized or the requested DSN address range is not in accordance with the current authorized data integrity verification allocation period, indicate that the requesting entity may be compromised.

20. The DS module of claim 19 further comprises:

after performing the encoded data slice integrity status evaluation operation, the second module further functions to indicate that the encoded data slice integrity status evaluation operation was performed on the requested DSN address range in accordance with the current authorized data integrity verification allocation period such that a second request from the requesting entity while the current authorized data integrity verification allocation period is active would be determined to be unauthorized.

21. The DS module of claim 19, wherein the second module functions to perform the encoded data slice integrity status evaluation operation in accordance with the encoded data slice integrity status request by at least one of:

when the encoded data slice integrity status request includes a slice list request, generating a list of slice names associated with the requested DSN address range to produce the encoded data slice integrity status response;

when the encoded data slice integrity status request includes a slice list digest request, generating the list of slice names associated with the requested DSN address range and generating a digest of the list of slice names to produce the encoded data slice integrity status response; and

when the encoded data slice integrity status request includes a slice integrity request;

generating at least one slice digest for at least one slice associated with the requested DSN address range;

for each slice digest of the at least one slice digest, comparing a retrieved slice digest to the slice digest to produce comparing results; and

generating the encoded data slice integrity status response to include the comparing results.

22. The DS module of claim 19 further comprises:

the first module further functions to obtain the current authorized data integrity verification allocation period from a trusted source, wherein the current authorized data integrity verification allocation period is a currently active version of one of a plurality of authorized data integrity verification allocation scenarios.