Location-independent RAID group virtual block management

• US 7,660,966 B2
• Filed: 08/02/2006
• Issued: 02/09/2010
• Est. Priority Date: 03/21/2003
• Status: Active Grant

• Current Assignee: NetApp, Inc.
• Original Assignee: NetApp, Inc.
• Inventors: Schoenthal, Scott, Doucette, Douglas P., Viswanathan, Srinivasan, Strange, Stephen H.
• Primary Examiner(s): Portka; Gary J
• Application Number:
  US11/497,590
• Publication Number:
  US 20060271734A1
• Time in Patent Office: 1,287 Days
• Field of Search: None
• US Class Current: 711/209
• CPC Class Codes: G06F 11/1092 Rebuilding, e.g. when physically replacing a failing disk
• CPC Class Codes: G06F 11/2056 by mirroring
• CPC Class Codes: G06F 2211/1023 Different size disks, i.e. non uniform size of disks in RAID systems with parity
• CPC Class Codes: G06F 3/0607 by facilitating the process of upgrading existing storage systems, e.g. for improving compatibility between host and storage device
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0665 at area level, e.g. provisioning of virtual or logical volumes
• 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 storage operating system is configured to assign volume block numbers (VBNs) to a volume. The system has a plurality of disks, and each disk of the plurality of disks is assigned disk block numbers (DBNs). A raidmap is configured to map the VBNs to the DBNs of the plurality of physical disks, the mapping for a particular disk stored in a disk label for the particular disk. The disk label for the particular disk is then written to the particular disk.

Claims

1. A method for operating a computer data storage system, comprising:

assigning volume block numbers (VBNs) to a volume;

assigning disk block numbers (DBNs) to each of a plurality of physical disks, the storage system including the physical disks;

mapping the VBNs to the DBNs of the plurality of physical disks by mapping parameters, the mapping parameters to map a range of VBN numbers to a selected range of DBNs on a selected physical disk of the plurality of physical disks;

using a plurality of mapping parameters to map a selected VBN range of the VBN numbers to a plurality of DBN ranges on the selected physical disk of the plurality of physical disks, the plurality of mapping parameters arranged as one map;

creating a plurality of maps for the selected physical disk, the plurality of maps including the one map;

creating a plurality of map slots on the selected physical disk; and

storing a selected map of the plurality of maps in a selected one of the slots of the plurality of map slots on the selected physical disk.

2. The method of claim 1, further comprising:

arranging the plurality of physical disks into one or more RAID groups.

3. The method of claim 1, further comprising:

organizing the plurality of physical disks as one or more physical disks supporting a volume.

4. The method of claim 1, further comprising:

mapping a range of VBNs to a range of DBNs of the selected physical disk of the plurality of physical disks.

5. The method of claim 1, further comprising:

mapping a plurality of VBN ranges to the selected physical disk to produce a noncontiguous VBN-to-DBN mapping on the selected physical disk.

6. The method of claim 1, further comprising:

mapping a base offset into a VBN range of the volume, a corresponding base offset into a DBN range of a related physical disk, and a size of DBN-to-VBN mapping.

7. The method of claim 1, further comprising:

exporting the mapping parameters from the plurality of physical disks to a memory of the storage system.

23. The method of claim 1 further comprising:

storing the mapping parameters as a data structure.

50. The method as in claim 1, further comprising:

flipping the computer data storage system from using a first map stored in a first map slot of the plurality of map slots to using a second map stored in a second map slot of the plurality of map slots; and

operating transactionally to allow for concurrent I/O operations and to view a configuration of the computer data storage system in a coherent manner.

8. A computer storage system, comprising:

a storage operating system configured to assign volume block numbers (VBNs) to a volume;

a plurality of disks, each disk of the plurality of disks assigned disk block numbers (DBNs);

the storage operating system further configured to use mapping parameters by mapping the VBNs to the DBNs of the plurality of disks, the mapping parameters further configured to map a range of VBN numbers to a selected range of DBNs on a disk of the plurality of disks;

a plurality of the mapping parameters configured to map a selected VBN range of the contiguous range of the VBN numbers to a plurality of DBN ranges on a selected disk of the plurality of disks, the plurality of mapping parameters arranged as a first map;

a disk file configured to store the plurality of mapping parameters to the selected disk to provide a mapping of non-contiguous VBNs to the selected disk;

a new disk to be added to the plurality of physical disks;

a plurality of maps created for the new disk, the plurality of maps including the first map;

a plurality of map slots created on the new disk; and

a selected map of the plurality of maps stored in a selected one of the slots of the plurality of map slots on the new disk.

9. The apparatus of claim 8, further comprising:

the plurality of disks organized into a RAID group.

10. The apparatus of claim 8, further comprising:

a RAID subsystem configured to organize the plurality of disks into one or more RAID groups.

11. The apparatus of claim 8, further comprising:

a plurality of ranges of VBNs configured to map to a plurality of ranges of DBNs of the selected disk of the plurality of disks to provide the mapping of noncontiguous VBNs to the new disk.

12. The apparatus of claim 8, further comprising:

input/output operations of the storage operating system to write noncontiguous VBN range on the new disk.

13. The apparatus of claim 8, further comprising:

the plurality of mapping parameters stored on the disk label file includes;

a base offset into a VBN range of the volume, a base offset into a DBN range corresponding to the VBN range, and a size of DBN-to-VBN mapping included in the mapping parameters.

14. The apparatus of claim 8, further comprising:

a subsystem to export the mapping parameters to a memory of the storage system.

24. The storage operating system of claim 8 further comprising:

the mapping parameters configured as a data structure.

25. The system of claim 8 further comprising:

the mapping parameters further configured to correlate a base offset into a VBN range of the volume, a corresponding base offset into a DBN range of a related disk, and a size of DBN-to-VBN mapping.

51. The computer storage system of claim 8, further comprising:

the first map stored in a first map slot of the plurality of map slots and a second map stored in a second map slot of the plurality of map slots; and

a process to flip the storage system from using the first map to using the second map while operating transactionally to allow for concurrent I/O operations and to view a configuration of the computer data storage system in a coherent manner.

15. A method for operating a storage system in the event of a disk failure, comprising:

assigning a range of volume block numbers (VBNs) to a volume;

assigning disk block numbers (DBNs) to each of a plurality of physical disks, the storage system including the physical disks;

creating a first mapping parameters to map a first range of VBN numbers to a first selected range of DBNs to reconstruct a failed physical disk using a first portion of a replacement disk;

creating a second mapping parameters to map a second range of VBN numbers to a second selected range of DBNs on a second portion of the replacement disk;

creating a first disk map using the first mapping parameters;

creating a second disk map using the second mapping parameters

creating a plurality of map slots on the replacement disk;

storing the first disk map in a first map slot of the plurality of map slots;

storing the second disk map in a second map slot of the plurality of map slots;

reconstructing a failed disk using the first disk map stored in the first map slot of the replacement disk; and

causing the storage system to flip from the first disk map to the second map stored in the second map slot of the replacement disk to provide an additional storage capacity of the replacement disk to the storage system.

16. The method of claim 15, further comprising:

replacing the failed physical disk with a larger disk.

17. The method of claim 16, further comprising:

mapping a capacity of the larger disk into group the storage system.

18. The method of claim 15, further comprising:

enabling separation of a plurality of DBN ranges of a DBN space of the replacement disk into a plurality of VBN ranges of the volume.

19. The method of claim 15, further comprising:

configuring the plurality of disks into a RAID group of the storage system, the RAID group managing storage and retrieval of information, including the mapping parameters.

20. The method of claim 19, further comprising:

exporting the mapping parameters from the RAID group to a write allocator of the storage system, the write allocator using the mapping parameters in performing input/output operations.

21. The method of claim 15, further comprising:

a using the second portion of the replacement disk for an extended range of the VBN space.

22. The method of claim 21, further comprising:

using a replacement disk having greater capacity than the failed disk; and

mapping an extended range of the VBN space into a portion of a disk block number (DBN) space of the replacement disk, the portion of the DBN space obtained from a capacity exceeding a capacity of the failed disk.

26. The method of claim 15 further comprising:

storing the mapping parameters as a data structure.

27. The method of claim 15 further comprising:

mapping a base offset into a VBN range of the volume, a corresponding base offset into a DBN range of a related disk, and a size of DBN-to-VBN mapping.

52. The method of claim 15, further comprising:

causing the storage system to flip from the first disk map to the second disk map while operating transactionally to allow for concurrent I/O operations and to view a configuration of the computer data storage system in a coherent manner.

28. A method for operating a storage system, comprising:

assigning a volume block numbers (VBNs) to a volume;

assigning a disk block numbers (DBNs) to each of a plurality of disks, the storage system including the disks;

correlating the VBNs to the DBNs of the plurality of disks by parameters, the parameters to correlate a range of VBN numbers to a selected range of DBNs on a selected disk of the plurality of disks;

storing the parameters on the selected disk to provide a correlation of noncontiguous VBN numbers to the DBN numbers of the selected disk;

adding a new disk to the plurality of disks;

creating a plurality of maps for the new disk;

creating a plurality of map slots on the new disk; and

storing a selected map of the plurality of maps in a selected one of the slots of the plurality of map slots on the new disk.

29. The method of claim 28 further comprising:

using placeholders for multiple per-disk VBN range data on the selected disk.

30. The method of claim 28 further comprising:

separating disk block number (DBN) ranges from correlated VBN ranges of the volume.

31. The method of claim 28 further comprising:

determining noncontiguous VBN-to-DBN correlations within a RAID group.

32. The method of claim 28 further comprising:

dynamically extending the VBN range at a RAID level without requiring reorganization of existing blocks in the storage system.

33. The method of claim 28 further comprising:

replacing a failed disk with a larger disk.

34. The method of claim 28 further comprises:

storing the first and second parameters on a location on the selected disk.

35. The method of claim 28 wherein the parameters further comprises:

maintaining information of a file system to correlate a VBN space of the volume to a DBN space of disks in the volume.

36. The method of claim 28 further comprising:

managing multiple correlated VBN ranges within disks and RAID groups, as well as noncontiguous VBN ranges across the RAID groups in the volume.

37. The method of claim 28 further comprising:

correlating a base offset into a VBN range of the volume, a corresponding base offset into a DBN range of a related disk, and a size of DBN-to-VBN correlation.

38. The method of claim 28 further comprising:

storing the parameters in a RAID group.

39. The method of claim 28 further comprising:

storing a disk number in the parameters.

40. The method of claim 28 further comprising:

storing a map number in the parameters.

41. The method of claim 28 further comprising:

storing the parameters as a data structure.

42. The method of claim 28 further comprising:

storing the parameters in a cache.

43. The method of claim 28 further comprising:

describing a topology of the volume by the parameters.

44. A computer readable storage media having program instructions for execution on a processor for a method of operating a storage system, the method comprising:

assigning volume block numbers (VBNs) to a volume;

assigning disk block numbers (DBNs) to each of a plurality of disks, the storage system including the disks;

creating a first parameters to correlate a first range of VBN numbers to a first selected range of DBNs;

creating a second parameters to correlate a second range of VBN numbers to a second selected range of DBNs;

creating a first disk map using the first mapping parameters;

creating a second disk map using the second mapping parameters

creating a plurality of map slots on a selected physical disk;

storing the first disk map in a first map slot of the plurality of map slots;

storing the second disk map in a second map slot of the plurality of map slots;

reconstructing a failed disk using the first disk map stored in the first map slot of the selected physical disk; and

causing the storage system to flip from the first disk map to the second map stored in the second map slot of the selected physical disk to provide an additional storage capacity of the selected physical disk to the storage system.

45. A storage operating system apparatus, comprising:

the storage operating system configured to assign volume block numbers (VBNs) to a volume;

the storage operating system further configured to assign disk block numbers (DBNs) to each of a plurality of disks, the storage system including the disks;

the storage operating system further configured to correlate the VBNs to the DBNs of the plurality of disks by parameters, the parameters configured to correlate a range of VBN numbers to a selected range of DBNs on a selected disk of the plurality of disks;

the storage operating system further configured to create a first parameters to correlate a first range of VBN numbers to a first selected range of DBNs;

the storage operating system further configured to create a second parameters to correlate a second range of VBN numbers to a second selected range of DBNs;

the selected disk configured to store the first and second parameters to provide a correlation of non-contiguous VBN numbers to the selected disk;

a new disk added to the plurality of disks;

a plurality of maps created for the new disk;

a plurality of map slots created on the new disk; and

a selected map of the plurality of maps stored in a selected one of the slots of the plurality of map slots on the selected physical disk.

53. The storage operating system apparatus of claim 45, further comprising:

a new map stored in a first map slot of the plurality of map slots of the new disk; and

a process to flip the storage system to using the new map while operating transactionally to allow for concurrent I/O operations and to view a configuration of the computer data storage system in a coherent manner.

46. A computer readable storage media having program instructions for execution on a processor to operate a storage system, the method comprising:

assigning volume block numbers (VBNs) to a volume;

assigning disk block numbers (DBNs) to each of a plurality of disks, the storage system including the disks;

using a plurality of parameters to correlate a selected VBN range of the range of VBN numbers to a plurality of DBN ranges on disks of the plurality of physical disks;

storing the plurality of parameters for the selected disk to the selected disk to provide a correlation of non-contiguous VBN numbers to the selected disk;

adding a new disk to the plurality of disks;

creating a plurality of maps for the new disk;

creating a plurality of map slots on the new disk; and

storing a selected map of the plurality of maps in a selected one of the slots of the plurality of map slots on the new disk.

47. A computer readable storage media having program instructions for execution on a processor for a method of operating a storage system in the event of a disk failure, the method comprising:

assigning volume block numbers (VBNs) to a volume;

assigning disk block numbers (DBNs) to each of a plurality of disks, the storage system including the disks;

creating a first parameters to correlate a first range of VBN numbers to a first selected range of DBNs to reconstruct a failed disk using a first portion of a replacement disk;

creating a second parameters to correlate a second range of VBN numbers to a second selected range of DBNs;

creating a plurality of map slots on the replacement disk;

creating a first new map for the replacement disk, the first new map mapping VBN space to DBN space in accordance with a map of the failed disk, and storing the first new map in a first map slot of the plurality of map slots;

reconstructing the failed disk onto the replacement disk using the first new map;

mapping new VBN numbers for volumes in the storage system to new DBN numbers of the additional disk capacity of the replacement disk using a second new map, the second new map including the first new map;

storing the second new map into a second map slot of the plurality of map slots; and

causing the storage system to flip from the first new map to the second new map to provide the additional storage capacity of the replacement disk to the storage system.

48. A method for operating a computer storage system, comprising:

assigning volume block numbers (VBNs) to a volume;

assigning disk block numbers (DBNs) to each of a plurality of disks, the storage system including the disks;

using a plurality of parameters to correlate a selected VBN range of the range of VBN numbers to a first selected DBN range on disks of the plurality of disks;

removing a failed disk from the storage system

adding a new disk to the plurality of disks;

creating a plurality of map slots on the new disk;

creating a first new map for the new disk, the first new map mapping VBN space to DBN space in accordance with a map of the failed disk, and storing the first new map in a first map slot of the plurality of map slots;

reconstructing the failed disk onto the new disk using the first new map;

mapping new VBN numbers for volumes in the storage system to new DBN numbers of the additional disk capacity of the new disk using a second new map, the second new map including the first new map;

storing the second new map into a second map slot of the plurality of map slots; and

causing the storage system to flip from the first new map to the second new map to provide the additional storage capacity of the new disk to the storage system.

54. The method of claim 48, further comprising:

causing the storage system to flip from the first new map to the second new map while operating transactionally to allow for concurrent I/O operations and to view a configuration of the computer data storage system in a coherent manner.

49. A method for operating a storage system, comprising:

assigning volume block numbers (VBNs) to a volume;

assigning disk block numbers (DBNs) to each of a plurality of storage devices, the storage system including the storage devices;

utilizing data structures to map VBN ranges into a DBN space of each storage device of the plurality of storage devices, wherein each data structure includes mapping parameters;

storing the data structure for each storage device to each storage device to provide a mapping of non-contiguous VBNs; and

adding a new storage device to the plurality of storage devices;

creating a plurality of map slots on the new storage device;

creating a first new map for the new storage device, the first new map mapping VBN space to DBN space of the new storage device, the DBN space of the first new map chosen to agree with DBN space of existing storage devices;

storing the first new map in a first map slot of the plurality of map slots;

mapping new VBN numbers for volumes in the storage system to new DBN numbers of an additional storage device capacity of the new storage device using a second new map, the second new map including the first new map;

storing the second new map into a second map slot of the plurality of map slots; and

causing the storage system to flip from the first new map to the second new map to provide the additional storage capacity of the new storage device to the storage system.

55. The method of claim 49, further comprising:

causing the storage system to flip from the first new map to the second new map while operating transactionally to allow for concurrent I/O operations and to view a configuration of the computer data storage system in a coherent manner.

56. A method for operating a computer data storage system, comprising:

assigning volume block numbers (VBNs) to a volume;

assigning data storage device block numbers (DBNs) to each of a plurality of physical data storage devices, the storage system including the physical data storage devices;

mapping the VBNs to the DBNs of the plurality of physical data storage devices by mapping parameters, the mapping parameters to map a range of VBN numbers to a selected range of DBNs on a selected physical data storage device of the plurality of physical data storage devices;

creating a plurality of VBN to DBN maps for the selected physical data storage device;

storing the plurality of VBN to DBN maps on the selected physical data storage device;

operating the data storage device using a first map of the plurality of VBN to DBN maps; and

causing the selected physical data storage device to flip from the first map to a second map of the plurality of VBN to DBN maps stored on the selected physical data storage device.

57. The method of claim 56, further comprising:

using a disk as the selected physical data storage device.

58. The method of claim 56, further comprising:

using a RAID system of disks as the selected physical data storage device.

59. The method of claim 56, further comprising:

using a computer readable media as the selected physical data storage device.

60. The method of claim 56, further comprising:

using an attached array of writable storage device media as the selected physical data storage device.

61. The method of claim 56, further comprising:

using a video tape as the selected physical data storage device.

62. The method of claim 56, further comprising:

using an optical media as the selected physical data storage device.

63. The method of claim 56, further comprising:

using a magnetic tape as the selected physical data storage device.

64. The method of claim 56, further comprising:

using a bubble memory as the selected physical data storage device.

65. The method of claim 56, further comprising:

using an electronic random access memory as the selected physical data storage device.

66. The method of claim 56, further comprising:

using a micro-electro mechanical media as the selected physical data storage device.

67. The method of claim 56, further comprising:

removing a failed physical data storage device from the computer data storage system, the failed physical data storage device having a first data stored thereon;

introducing a new physical data storage device into the computer data system to replace the failed physical data storage device;

creating a first VBN to DBN map for the new physical data storage device, the first VBN to DBN map to store data originally stored on the failed physical data storage device on the new physical data storage device;

creating a second VBN to DBN map for the new physical data storage device, the second VBN to DBN map to assign new VBN space to new DBN space provided by the new physical data storage device;

reconstructing the first data stored on the failed physical data storage device using the first VBN to DBN map;

causing the computer data storage device to flip from using the first map to using the second map to provide the new DBN space to the computer data storage system.

68. The method as in claim 56, further comprising:

adding a new physical data storage device to the computer data storage system;

creating a new VBN to DBN map for the new physical data storage device;

integrating the new VBN to DBN map into the computer data storage system to provide new storage capacity to the computer data storage system.

69. A computer data storage apparatus, comprising:

volume block numbers (VBNs) assigned to a volume;

data storage device block numbers (DBNs) assigned to each of a plurality of physical data storage devices, the storage system including the physical data storage devices;

a processor of the computer data storage system to,

map the VBNs to the DBNs of the plurality of physical data storage devices by mapping parameters, the mapping parameters to map a range of VBN numbers to a selected range of DBNs on a selected physical data storage device of the plurality of physical data storage devices;

create a plurality of VBN to DBN maps for the selected physical data storage device;

store the plurality of VBN to DBN maps on the selected physical data storage device;

operate the data storage device using a first map of the plurality of VBN to DBN maps; and

cause the selected physical data storage device to flip from the first map to a second map of the plurality of VBN to DBN maps stored on the selected physical data storage device.

70. The apparatus of claim 69, further comprising:

a disk used as the selected physical data storage device.

71. The apparatus of claim 69, further comprising:

a RAID system of disks used as the selected physical data storage device.

72. The apparatus of claim 69, further comprising:

a computer readable media used as the selected physical data storage device.

73. The apparatus of claim 69, further comprising:

an attached array of writable storage device media used as the selected physical data storage device.

74. The apparatus of claim 69, further comprising:

a video tape used as the selected physical data storage device.

75. The apparatus of claim 69, further comprising:

an optical media used as the selected physical data storage device.

76. The apparatus of claim 69, further comprising:

a magnetic tape used as the selected physical data storage device.

77. The apparatus of claim 69, further comprising:

a bubble memory used as the selected physical data storage device.

78. The apparatus of claim 69, further comprising:

an electronic random access memory used as the selected physical data storage device.

79. The apparatus of claim 69, further comprising:

a micro-electro mechanical media used as the selected physical data storage device.

80. The apparatus of claim 69, further comprising:

a failed physical data storage device which is removed from the computer data storage system, the failed physical data storage device having a first data stored thereon;

a new physical data storage device introduced into the computer data system to replace the failed physical data storage device;

a first VBN to DBN map created for the new physical data storage device, the first VBN to DBN map to store data originally stored on the failed physical data storage device on the new physical data storage device;

a second VBN to DBN map created for the new physical data storage device, the second VBN to DBN map to assign new VBN space to new DBN space provided by the new physical data storage device;

the processor to reconstruct the first data stored on the failed physical data storage device using the first VBN to DBN map;

the processor executing a process to cause the computer data storage device to flip from using the first map to using the second map to provide the new DBN space to the computer data storage system.

81. The apparatus as in claim 69, further comprising:

a new physical data storage device added to the computer data storage system;

a new VBN to DBN map for the new physical data storage device;

the processor to integrate the new VBN to DBN map into the computer data storage system to provide new storage capacity to the computer data storage system.

82. A computer readable storage media having program instructions for execution on a processor for a method of operating a computer data storage system, the method comprising:

assigning volume block numbers (VBNs) to a volume;

assigning data storage device block numbers (DBNs) to each of a plurality of physical data storage devices, the storage system including the physical data storage devices;

mapping the VBNs to the DBNs of the plurality of physical data storage devices by mapping parameters, the mapping parameters to map a range of VBN numbers to a selected range of DBNs on a selected physical data storage device of the plurality of physical data storage devices;

creating a plurality of VBN to DBN maps for the selected physical data storage device;

storing the plurality of VBN to DBN maps on the selected physical data storage device;

operating the data storage device using a first map of the plurality of VBN to DBN maps; and

causing the selected physical data storage device to flip from the first map to a second map of the plurality of VBN to DBN maps stored on the selected physical data storage device.