Mirrored disk partition with disk partition modification contemporaneous with client application access

• US 20040162955A1
• Filed: 02/18/2003
• Published: 08/19/2004
• Est. Priority Date: 02/18/2003
• Status: Active Grant

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Suen, Lai-Cherng, Kwong, Man K., Jones, Jerry, Ng, Ming Yong
• Granted Patent: US 6,941,430 B2
• Time in Patent Office: Days
• US Class Current: 711/162
• 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 3/0632 by initialisation or re-initialisation of storage systems
• CPC Class Codes: G06F 3/0644 Management of space entities, e.g. partitions, extents, pools
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 8/656 while running
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99955 Archiving or backup

Abstract

A first content portion of a first disk partition is mirrored to a second content portion of a second disk partition. A first one of the first content portion and the second content portion that is modified contemporaneously with access by one or more client applications to one or more subpoitions of a second one of the first content portion and the second content portion.

Claims

1. A method, comprising the steps of:

mirroring a first content portion of a first disk partition to a second content portion of a second disk partition; and

modifying a first one of the first content portion and the second content portion contemporaneously with access by one or more client applications to one or more subportions of a second one of the first content portion and the second content portion.

2. The method of claim 1, wherein a first metadevice is associated with the first disk partition, wherein the step of mirroring the first content portion of the first disk partition to the second content portion of the second disk partition comprises the steps of:

detaching a submirror associated with the second disk partition from a second metadevice; and

attaching the submirror to the first metadevice associated with the first disk partition.

3. The method of claim 1, wherein the step of modifying the first one of the first content portion and the second content portion contemporaneously with access by the one or more client applications to the one or more subportions of the second one of the first content portion and the second content portion comprises the steps of:

detaching a submirror associated with the first disk partition from a first metadevice associated with a primary file system;

attaching the submirror to a second metadevice associated with a secondary file system; and

employing the secondary file system to modify the first content portion of the first disk partition.

4. The method of claim 3, wherein a server computer comprises the submirror and the first metadevice, the method further comprising the step of:

running a startup script after a reboot of the server computer to reconfigure a connection path between the submirror and the first metadevice.

5. The method of claim 3, wherein the step of employing the secondary file system to modify the first content portion of the first disk partition comprises the step of:

accessing the first disk partition through a connection path that comprises the secondary file system, the second metadevice, and the submirror.

6. The method of claim 1, wherein the step of modifying the first one of the first content portion and the second content portion contemporaneously with access by the one or more client applications to the one or more subportions of the second one of the first content portion and the second content portion comprises the steps of:

attaching a second submirror associated with the second disk partition to a first metadevice associated with a primary file system;

detaching a first submirror associated with the first disk partition from a metadevice associated with the primary file system; and

employing the second disk partition to support one or more of the one or more client applications through the primary file system.

7. The method of claim 1, wherein the step of modifying the first one of the first content portion and the second content portion contemporaneously with access by the one or more client applications to the one or more subportions of the second one of the first content portion and the second content portion comprises the steps of:

modifying one or more operating system files stored in the first disk partition; and

actively operating one or more operating system files stored in the second disk partition;

wherein the one or more operating system files stored in the second disk partition comprise mirrored copies of the one or more operating system files stored in the first disk partition;

wherein the step of modifying the one or more operating system files stored in the first disk partition and the step of actively operating one or more operating system files stored in the second disk partition are contemporaneous.

8. The method of claim 1, wherein a first operating system is stored in the first disk partition, wherein a mirrored copy of the first operating system is stored in the second disk partition, wherein the step of modifying the first one of the first content portion and the second content portion contemporaneously with access by the one or more client applications to the one or more subportions of the second one of the first content portion and the second content portion comprises the steps of:

updating the first operating system stored in the first disk partition to a second operating system; and

actively operating the mirrored copy of the first operating system stored in the second disk partition;

wherein the step of updating the first operating system stored in the first disk partition to the second operating system and the step of actively operating the mirrored copy of the first operating system stored in the second disk partition are contemporaneous.

9. The method of claim 8, wherein the step of updating the first operating system stored in the first disk partition to the second operating system comprises the steps of:

deleting from the first disk partition a file that is used by the first operating system and unused by the second operating system;

adding to the first disk partition a file that is used by the second operating system and unused by the first operating system; and

maintaining in the first disk partition a file that is used by both of the first operating system and the second operating system.

10. The method of claim 9, further comprising the step of:

adding one or more user specific software packages from the first operating system to the second operating system.

11. The method of claim 1, wherein the first content portion comprises one or more first files of an operating system, wherein a third content portion comprises one or more second files of the operating system, the method further comprising the steps of:

updating one or more outdated files of the one or more second files to one or more updated files contemporaneously with active performance of the operating system;

storing in a first subdirectory of the third content portion the one or more old files; and

storing in a second subdirectory of the third content portion the one or more updated files.

12. The method of claim 11, wherein the operating system comprises a first operating system, wherein the step of updating the one or more old files of the one or more second files to the one or more updated files contemporaneously with active performance of the operating system comprises the steps of:

comparing the first operating system with a second operating system that comprises the one or more updated files; and

determining one or more files that are common to the first operating system and the second operating system.

13. The method of claim 12, further comprising the steps of:

storing in a third subdirectory of the third content portion the one or more files that are common to the first operating system and the second operating system; and

accessing the one or more files of the third subdirectory through employment of any of the first and second subdirectories.

14. The method of claim 11, further comprising the step of:

loopback mounting any one of the first subdirectory and the second subdirectory as a primary directory of the third content portion used by the operating system.

15. The method of claim 1, further comprising the steps of:

coupling the first disk partition with a first file system through one or more first metadevices; and

coupling the second disk partition with a second file system through one or more second metadevices.

16. The method of claim 1, wherein the step of modifying the first one of the first content portion and the second content portion results in a modification of one of the first content portion and the second content portion, the method further comprising the steps of:

recording in a startup script a progress of the modification; and

employing the startup script to resume the modification at a point in the progress upon an interruption in the modification.

17. An apparatus, comprising:

a first disk partition that stores contents of a primary file system;

a second disk partition that is able to store the contents of the primary file system;

a first submirror that is associated with the first disk partition and a first metadevice, wherein the first metadevice is associated with the primary file system; and

a second submirror that is associated with the second disk partition and a second metadevice, wherein the second metadevice is associated with a secondary file system;

wherein a detachment of the second submirror from the second metadevice and an attachment of the second submirror with the first metadevice serves to transfer a mirrored copy of the contents of the primary file system to the second disk partition;

wherein a detachment of the first submirror from the first metadevice and an attachment of the first submirror with the second metadevice serve to facilitate modification of the contents of the primary file system through the second metadevice contemporaneously with access to the contents of the primary file system through the first metadevice.

18. The apparatus of claim 17, wherein the modification of the contents of the primary file system comprises an operating system update.

19. The apparatus of claim 17, wherein a partitioning of the second disk partition results in an exclusion of a disk label, wherein the exclusion of the disk label serves to allow the contents of the primary file system of the first disk partition to be mirrored to the second disk partition.

20. An article, comprising:

one or more computer-readable signal-bearing media; and

means in the one or more media for mirroring a first content portion of a first disk partition to a second content portion of a second disk partition; and

means in the one or more media for modifying a first one of the first content portion and the second content portion contemporaneously with access by one or more client applications to one or more subportions of a second one of the first content portion and the second content portion.