Method to automatically determine host to LUN (logical unit number) path availability for multi path attached storage systems

• US 20090228748A1
• Filed: 03/04/2008
• Published: 09/10/2009
• Est. Priority Date: 03/04/2008
• Status: Active Grant

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: LSI Corporation (Broadcom, Inc.)
• Inventors: Stankey, Robert R. JR., Ziegler, Mark, Tefft, Glenn, Hagerott, Steven G.
• Granted Patent: US 8,332,505 B2
• Time in Patent Office: Days
• US Class Current: 714/718
• CPC Class Codes: G06F 11/2089 Redundant storage control functionality
• CPC Class Codes: G06F 11/2215 to test error correction or detection circuits

Abstract

The present disclosure provides testing of a storage system. The test may compare the storage array controller LUNs which may be configured to be accessible by a host with the LUNs which are currently available to prevent a zero path scenario from occurring. The test may verify at least one path exists for each LUN to a storage controller of a storage array before injecting an error into another storage controller of the storage array. The present disclosure also provides verification of the configuration of a storage system. The configuration verification may verify that the storage array controller LUNs which are configured to be accessible by a host are actually accessible by the host. If the configuration verification is unable to verify the configuration of storage system, the configuration verification may display an error.

Claims

1. A method, comprising:

generating a first set of at least one LUN (logical unit number) of a storage array that is configured to be accessible from a host;

generating a second set of at least one LUN of said storage array that is accessible from said host;

comparing the first set to the second set; and

determining whether a LUN of the first set is present in the second set.

2. The method as claimed in claim 1, wherein said generating a first set of at least one LUN (logical unit number) of a storage array that is configured to be accessible from a host comprises:

querying said storage array to determine a WWN (world wide name) of said storage array, a WWN for each LUN of said storage array, and a WWN of a HBA (host bus adapter) associated with each one of said each LUN of said storage array; and

querying said host to determine a network address of said host associated with said WWN of said HBA.

3. The method as claimed in claim 2, wherein said querying said storage array comprises:

querying said storage array utilizing a remote procedure call (RPC) application programming interface (API).

4. The method as claimed in claim 1, wherein said generating a second set of at least one LUN of said storage array that is accessible from said host comprises:

querying a failover driver of said host to generate said second set of at least one LUN of said storage array that is accessible from said host.

5. The method as claimed in claim 1, further comprising:

displaying an error when a LUN of the first set is not present in the second set.

6. A method, comprising:

running a test on a storage system comprising a host and a storage array;

generating a first set of at least one path configured to be accessible between a LUN (logical unit number) of said storage array and said host;

generating a second set of at least one path accessible between said LUN of said storage array and said host;

comparing the first set to the second set;

determining a path of said first set associated with a first controller of said storage array is present in said second set prior to injecting a fault to a second controller of said storage array; and

injecting said fault to said second controller of said storage array.

7. The method as claimed in claim 6, wherein said generating a first set of at least one path configured to be accessible between a LUN (logical unit number) of said storage array and said host comprises:

querying said storage array to determine a WWN (world wide name) of said storage array, a WWN for each LUN of said storage array, and a WWN of a HBA (host bus adapter) associated with each one of said each LUN of said storage array; and

querying said host to determine a network address of said host associated with said WWN of said HBA.

8. The method as claimed in claim 7, wherein said querying said storage array comprises:

querying said storage array utilizing a remote procedure call (RPC) application programming interface (API).

9. The method as claimed in claim 6, wherein said generating a first set of at least one path configured to be accessible between a LUN (logical unit number) of said storage array and said host comprises:

obtaining a WWN (world wide name) of said storage array from a first input to said test; and

obtaining a network address of said host associated with said WWN of said HBA from a second input to said test.

10. The method as claimed in claim 6, wherein said generating a second set of at least one path accessible between said LUN of said storage array and said host comprises:

querying a failover driver of said host to generate said second set of at least one path accessible between said LUN of said storage array and said host.

11. The method of claim 6, wherein said determining a path of said first set associated with a first controller of said storage array is present in said second set prior to injecting a fault to a second controller of said storage array comprises:

locking said second controller wherein said fault cannot be injected to said second controller when said second controller is locked;

determining a path of said first set associated with a first controller of said storage array is present in said second set; and

unlocking said second controller.

12. The method of claim 11, wherein said second controller is locked utilizing a semaphore associated with said second controller.

13. The method of claim 6, further comprising:

recovering said second controller of said storage array from said fault;

updating said second set of at least one path accessible between said LUN of said storage array and said host;

determining a path of said first set associated with said second controller of said storage array is present in said second set prior to injecting an additional fault to said first controller of said storage array; and

injecting said additional fault to said first controller of said storage array.

14. The method of claim 13 wherein said determining a path of said first set associated with said second controller of said storage array is present in said second set prior to injecting an additional fault to said first controller of said storage array comprises:

locking said first controller wherein said additional fault cannot be injected to said first controller when said first controller is locked;

determining a path of said first set associated with a second controller of said storage array is present in said second set; and

unlocking said first controller.

15. The method of claim 14, wherein said second controller is locked utilizing a semaphore associated with said second controller.

16. The method according to claim 13, further comprising:

recording a first time when recovering said second controller of said storage array;

recording a second time when determining a path of said first set associated with said second controller of said storage array is present in said second set; and

measuring a time difference between said first time and said second time.

17. Computer executable instructions, embodied in a tangible media, for performing a method comprising:

generating a first set of at least one LUN (logical unit number) of a storage array that is configured to be accessible from a host;

generating a second set of at least one LUN of said storage array that is accessible from said host;

comparing the first set to the second set; and

determining whether a LUN of the first set is present in the second set.

18. Computer executable instructions, embodied in a tangible media, for performing a method comprising:

running a test on a storage system comprising a host and a storage array;

generating a first set of at least one path configured to be accessible between a LUN (logical unit number) of said storage array and said host;

generating a second set of at least one path accessible between said LUN of said storage array and said host;

comparing the first set to the second set;

determining a path of said first set associated with a first controller of said storage array is present in said second set prior to injecting a fault to a second controller of said storage array; and

injecting said fault to said second controller of said storage array.

19. The computer executable instructions of claim 18, wherein the method performed by the computer executable instructions further comprises:

recovering said second controller of said storage array from said fault;

updating said second set of at least one path accessible between said LUN of said storage array and said host;

determining a path of said first set associated with said second controller of said storage array is present in said second set prior to injecting an additional fault to said first controller of said storage array; and

injecting said additional fault to said first controller of said storage array.

20. The computer executable instructions of claim 19, wherein the method performed by the computer executable instructions further comprises:

recording a first time when recovering said second controller of said storage array;

recording a second time when determining a path of said first set associated with said second controller of said storage array is present in said second set; and

measuring a time difference between said first time and said second time.