Method and system for filesystem mounted on a root directory wherein data is redirected from a first storage system to a second storage system

• US 7,257,652 B2
• Filed: 07/07/2003
• Issued: 08/14/2007
• Est. Priority Date: 07/07/2003
• Status: Active Grant

• Current Assignee: Oracle America, Inc. (Oracle Corporation)
• Original Assignee: Sun Microsystems Incorporated (Oracle Corporation)
• Inventors: Zhou, Shudong, Gilliam, Jerry A., Horne, Christopher J.
• Primary Examiner(s): PEYTON, TAMMARA R
• Application Number:
  US10/615,534
• Publication Number:
  US 20050010747A1
• Time in Patent Office: 1,499 Days
• Field of Search: 710/20, 710/38, 714/1, 714/2, 714/6, 711/100, 711/114, 711/162, 709/200, 709/202, 709/203
• US Class Current: 710/38
• CPC Class Codes: G06F 16/10 File systems; File servers

Abstract

An automated method of establishing a filesystem utilizing the establishment of a first filesystem that interfaces with devices by loading software, including a first set of drivers, into memory and initializing the first set of drivers with the devices. The first filesystem is then mounted on a root directory that comprises a single storage device. The method allows input/output functionality within the first filesystem and, while input/output functionality is available to the first filesystem, the method accesses the single storage device to obtain software, including a second set of drivers. The method loads the software into the memory and initializes the second set of drivers with the devices to establish a second filesystem. The second filesystem is mounted on a root directory comprising the single storage device and another storage device and the first filesystem is then rendered inactive.

Claims

1. An automated method of establishing a filesystem comprising:

a) establishing a first filesystem which interfaces with devices by loading software, including a first set of drivers, into memory and initializing said first set of drivers with said devices, said first filesystem mounted on a root directory comprising a single storage device;

b) allowing input/out functionality within said first filesystem; and

c) while input/output functionality is made available to said first filesystem, accessing said single storage device to obtain software, including a second set of drivers, and loading said software into said memory said initializing said second set of drivers with said devices to establish a second filesystem, wherein said second filesystem is mounted on a root directory comprising said single storage device and another storage device and wherein said first filesystem is rendered inactive.

2. A method as described in claim 1 wherein said single storage device and said another storage device comprise a mirrored pair of storage devices.

3. A method as described in claim 1 wherein said second filesystem comprises a volume manager.

4. A method as described in claim 2 wherein said second filesystem comprises a volume manager which directs input/output to and from said mirrored pair of storage devices.

5. A method as described in claim 1 wherein said devices comprise:

storage devices;

bus controller devices; and

bus devices.

6. A method as described in claim 1 further comprising an application program interfacing with said first filesystem and wherein said second filesystem is established transparently to said application program and further comprising said application program interfacing with said second filesystem after the establishment thereof.

7. A method as described in claim 1 wherein said software of said c) is determined dynamically.

8. A data storage system comprising a processor, a plurality of devices and a memory wherein said memory comprises instructions for implementing a method of transparently remounting filesystem comprising:

a) establishing a first filesystem which interfaces with said plurality of devices by loading software, including a first set of drivers, into said memory and initializing said first set of drivers with said plurality of devices, said first filesystem mounted on a root directory comprising a single storage device;

b) activating input/output functionality within said first filesystem; and

c) while input/output functionality is made available to said first filesystem, accessing said single storage device to obtain software, including a second set of drivers, and loading said software into said memory and initializing said second set of drivers with said plurality of devices to establish a second filesystem, wherein said second filesystem is mounted on a root directory comprising said single storage device and another storage device and wherein said first filesystem is rendered inactive.

9. A data storage system as described in claim 8 wherein said single storage device and said another storage device comprise a mirrored pair of storage devices.

10. A data storage system as described in claim 8 wherein said second filesystem comprises a volume manager.

11. A data storage system as described in claim 9 wherein said second filesystem comprises a volume manager which directs input/output to and from said mirrored pair of storage devices.

12. A data storage system as described in claim 8 wherein said plurality of devices comprise:

storage devices;

bus controller devices; and

bus devices.

13. A data storage system as described in claim 8 further comprising an application program interfacing with said first filesystem and wherein said second filesystem is established transparently to said application program and wherein said method further comprises said application program interfacing with said second filesystem after the establishment thereof.

14. A data storage system as described in claim 8 wherein said software of said c) is determined dynamically.

15. An automated method of establishing a filesystem for accessing a plurality of storage devices, said method comprising:

a) booting from a firmware program which comprises firmware drivers, wherein said booting comprises;

a1) using said firmware drivers, accessing a first set of drivers from a first storage device; and

a2) using said first set of drivers, establishing a first fileystem mounted on a root directory comprising said first storage device;

b) once said first filesystem is established, utilizing enabled input/output functionality of said first filesystem to said root directory to access a second set of drivers from said first storage device; and

c) using said second set of drivers, establishing a second filesystem mounted on a root directory comprising a plurality of storage devices including said first storage device and wherein said first filesystem is rendered inactive.

16. A method as described in claim 15 wherein said a2) comprises:

loading said first set of drivers into memory;

disabling said input/output functionality to said first storage device;

initializing said first set of drivers and devices associated with accessing said first storage device to attach said first filesystem to said storage device; and

resuming said input/output functionality to said first storage device.

17. A method as described in claim 15 wherein said plurality of storage devices comprise a mirrored pair of storage devices.

18. A method as described in claim 15 wherein said second filesystem comprises a volume manager.

19. A method as described in claim 15 wherein said first set of drivers are defined according to a predetermined forceload list within said firmware.

20. A method as described in claim 17 wherein said second filesystem comprises a volume manager which directs input/output to and from said mirrored pair of storage devices.

21. A method as described in claim 15 further comprising an application program interfacing with said first filesystem and wherein said second filesystem is established transparently to said application program and further comprising said application program interfacing with said second filesystem after the establishment thereof.

22. A method as described in claim 15 wherein said second set of drivers is determined dynamically.

23. A method as described in claim 19 wherein said second set of drivers is determined dynamically.

24. An automated method of transparently transferring from a first filesystem to a second filesystem comprising:

a) booting from a firmware program which comprises firmware drivers, wherein said booting comprises;

a1) using said firmware drivers, accessing a first set of drivers from a first storage device, said first set of drivers specified within a predetermined firmware listing; and

a2) using said first set of drivers, establishing a first filesystem mounted on a root directory comprising said first storage device;

b) once said first filesystem is established, utilizing enabled input/output functionality of said first filesystem to said root directory to access a second set of drivers from said first storage device and software for constructing a volume manager; and

c) using said second set of drivers and said software, establishing a second filesystem, comprising said volume manager, and mounted on a root directory comprising a plurality of storage devices configured as at least one mirrored pair and wherein said first fielsystem is rendered inactive.

25. A method as described in claim 24 wherein said second set of drivers is determined dynamically.

26. A method as described in claim 24 wherein said volume manager directs input/output to and from said at least one mirrored pair.

27. A method as described in claim 24 wherein said second filesystem is established transparently.