In-service raid mirror reconfiguring

• US 20050102603A1
• Filed: 11/07/2003
• Published: 05/12/2005
• Est. Priority Date: 11/07/2003
• Status: Active Grant

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Smith, Gary S., Guericke, Marty, Tapper, Gunnar, Bellam, Vijay M.
• Granted Patent: US 7,370,248 B2
• Time in Patent Office: Days
• US Class Current: 714/770
• CPC Class Codes: G06F 11/1662 the resynchronized component or unit being a persistent storage device re-synchronization of failed mirror storage G06F11/2082; rebuild or reconstruction of parity RAID storage G06F11/1008
• CPC Class Codes: G06F 11/2094 Redundant storage or storage space G06F11/2056 takes precedence

Abstract

This disclosure describes a technique including operating a redundant disk drive device, wherein the redundant disk drive device includes a primary disk drive and at least one mirror disk drive. At least one of the disk drives is reconfigured within the redundant disk drive system in such a manner that during the reconfiguring, the disk drive is maintained on-line.

Claims

1. A method comprising:

operating a redundant disk drive device, wherein the redundant disk drive device includes a primary disk drive and at least one mirror disk drive; and

reconfiguring at least one of the disk drives within the redundant disk drive system in such a manner that during the reconfiguring, the disk drive is maintained on-line.

2. A method of claim 1, wherein the reconfiguring the at least one redundant disk drive while maintaining the redundant disk drive system online comprises:

providing a first process and a second process, the first process and the second process each having an identical operating system image;

reconfiguring the first process while the state of the second process is maintained; and

applying error handling to the first process, wherein if an error is detected in the first process, the first process is returned based on the state of the second process, and wherein if no error is detected on the first process upon completion of the first process, then;

the state of the first process is maintained as;

the second process is reconfigured, and

applying error handling to the second process, wherein if an error is detected in the second process, the second process is forwarded based on the state of the first process that was completed.

3. The method of claim 2, wherein if when the second process is being reconfigured the error handling does not detect an error, the second process is maintained as completed.

4. The method of claim 1, wherein the redundant disk drive device includes a Redundant Array of Inexpensive Disks (RAID) system.

5. The method of claim 1, wherein the reconfiguring includes adding a mirror disk drive.

6. The method of claim 1, wherein the reconfiguring includes deleting a mirror disk drive.

7. The method of claim 1, wherein the reconfiguring includes switching a mirror disk drive for a primary disk drive.

8. The method of claim 1, further comprising checking the reconfigured disk for errors.

9. The method of claim 1, further comprising checking the reconfigured disk for errors, wherein if errors are found, the state of the redundant disk drive device is attempted to be returned to its original state prior to beginning the reconfiguring.

10. The method of claim 1, further comprising checking the reconfigured disk for errors, wherein if errors are found in the first process, the state of the redundant disk drive device is attempted to be transitioned to its state following the reconfiguring, after which point any detected errors are attempted to be corrected.

11. The method of claim 1, further comprising checking the reconfigured disk for errors based on a process pair including a first processor undergoing a first process and a second processor undergoing a second process, the first process is processed within the first processor as the initial state of the second processor is sustained, wherein if errors are found during the processing of the first process within the first processor, the state of the first processor is returned to its initial value at least partially using data contained within the second processor;

and

wherein if errors are found in the processing of the second process contained in the second processor after the first process has been successfully completed within the first process, then the state of the second processor is transitioned to its completed state following the reconfiguring at least partially using data from the completed processed value of the first process.

12. The method of claim 1, in which certain disk drives that are included within the redundant disk drive device are not configured automatically since they can be used as part of a pool of spare disk drives.

13. A method, comprising providing a Redundant Array of Inexpensive Disks (RAID) system:

and

beginning an online disk remirroring (ODR) operation between a primary process and a mirror process online, in which the identity of the process that performs the primary process is switched with the identity of a process that performs the mirror process.

14. The method of claim 13, wherein the ODR operation includes switching the identity of a disk drive that is performing the mirror process with the identity of a disk drive that is performing the primary process.

15. The method of claim 13, further comprising checking the remirrorred disk for errors.

16. The method of claim 13, further comprising checking the remirrorred disk for errors, wherein if errors are found, the state of the redundant disk drive device is attempted to be returned to its original state prior to beginning the remirrorred disk.

17. The method of claim 13, further comprising checking the remirrored disk for errors, wherein if errors are found, the state of the redundant disk drive device is attempted to be transitioned to its state following the remirrored disk, after which point any detected errors are attempted to be corrected.

18. The method of claim 13, further comprising checking the reconfigured disk for errors based on a process pair including a first processor undergoing a first process and a second processor undergoing a second process, the first process is processed within the first processor as the initial state of the second processor is sustained, wherein if errors are found during the processing of the first process within the first processor, the state of the first processor is returned to its initial value at least partially using data contained within the second processor;

and

wherein if errors are found in the processing of the second process contained in the second processor after the first process has been successfully completed within the first process, then the state of the second processor is transitioned to its completed state following the reconfiguring at least partially using data from the completed processed value of the first process.

19. A method, comprising

providing a disk memory system including at least one disk;

and

adding at least one disk to the disk memory system using an online disk reconfiguring operation to create, or add to, a redundant disk array, at least one disk in the redundant disk array performs a primary process while a separate disk in the disk array performs a mirror process, the adding the at least one disk is performed online.

20. The method of claim 19, further comprising checking the reconfigured disk for errors.

21. The method of claim 19, further comprising checking the reconfigured disk for errors, wherein if errors are found, the state of the redundant disk drive device is attempted to be returned to its original state prior to beginning the reconfiguring.

22. The method of claim 19, further comprising checking the reconfigured disk for errors, wherein if errors are found, the state of the redundant disk drive device is attempted to be transitioned to its state following the reconfiguring, after which point any detected errors are attempted to be corrected.

23. The method of claim 19, further comprising checking the reconfigured disk for errors based on a process pair including a first processor undergoing a first process and a second processor undergoing a second process, the first process is processed within the first processor as the initial state of the second processor is sustained, wherein if errors are found during the processing of the first process within the first processor, the state of the first processor is returned to its initial value at least partially using data contained within the second processor;

and

wherein if errors are found in the processing of the second process contained in the second processor after the first process has been successfully completed within the first process, then the state of the second processor is transitioned to its completed state following the reconfiguring at least partially using data from the completed processed value of the first process.

24. The method of claim 19, wherein the redundant disk array is included within a Redundant Array of Inexpensive Disks (RAID) system.

25. A method, comprising

providing a Redundant Array of Inexpensive Disks (RAID) system including a primary disk drive and a mirror disk drive;

and

removing the mirror disk drive from the RAID system while the RAID system is maintained on-line.

26. The method of claim 25, wherein an application program can be run on the RAID system as the mirror disk drive is being removed from the RAID system.

27. A computer readable memory having computer readable instructions that when executed by a process causes the process to:

operate a redundant disk drive device, the redundant disk drive device includes a primary disk drive and at least one mirror disk drive; and

reconfigure at least one of the disk drives within the redundant disk drive system in such a manner that during the reconfiguration, the disk drive is maintained on-line.

28. The computer readable memory of claim 27, wherein an application program can be run on the redundant disk drive device as at least one disk drive is being reconfigured.

29. The computer readable memory of claim 27, wherein the redundant disk drive device runs within a Redundant Array of Inexpensive Disks (RAID) system.

30. The computer readable memory of claim 27, further comprising checking the reconfigured disk for errors based on a process pair including a first processor undergoing a first process and a second processor undergoing a second process, the first process is processed within the first processor as the initial state of the second processor is sustained, wherein if errors are found during the processing of the first process within the first processor, the state of the first processor is returned to its initial value at least partially using data contained within the second processor;

and

wherein if errors are found in the processing of the second process contained in the second processor after the first process has been successfully completed within the first process, then the state of the second processor is transitioned to its completed state following the reconfiguring at least partially using data from the completed processed value of the first process.

31. An apparatus, comprising:

a Redundant Array of Inexpensive Disks (RAID) Management system that manages a disk array controller, the disk array controller operating a redundant disk drive device, wherein the redundant disk drive device includes a primary disk drive and at least one mirror disk drive; and

the RAID management system reconfigures at least one of the disk drives within the redundant disk drive system in such a manner that during the reconfiguring, the disk drive is maintained on-line.

32. The apparatus of claim 31, wherein the reconfiguring includes adding a mirror disk drive.

33. The apparatus of claim 31, wherein the reconfiguring includes removing a mirror disk drive.

34. The apparatus of claim 31, wherein the reconfiguring includes swapping a mirror disk drive for a primary disk drive.

35. A method to reconfigure a RAID system while maintaining the RAID system online, comprising:

providing a first process and a second process, the first process and the second process each having an identical operating system image;

reconfiguring the first process while the state of the second process is maintained; and

applying error handling to the first process, wherein if an error is detected in the first process, the first process is returned based on the state of the second process, and wherein if no error is detected on the first process upon completion of the first process, then;

the state of the first process is maintained as;

the second process is reconfigured, and

applying error handling to the second process, wherein if an error is detected in the second process, the second process is forwarded based on the state of the first process that was completed.

36. The method of claim 35, wherein if when the second process is being reconfigured the error handling does not detect an error, the second process is maintained as completed.

37. The method of claim 35, wherein if when the second process is being reconfigured the error handling does not detect an error, the second process is maintained as completed, and the completed first process is compared with the completed second process.

38. The method of claim 35, further comprising reconfiguring the RAID system including the two processes while maintaining the RAID system online.

39. The method of claim 35, wherein the first process is run within a first processor and the second process is run in a second processor.