FAILURE RECOVERY METHOD IN INFORMATION PROCESSING SYSTEM AND INFORMATION PROCESSING SYSTEM

• US 20120151250A1
• Filed: 12/14/2010
• Published: 06/14/2012
• Est. Priority Date: 12/14/2010
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Saika, Nobuyuki
• Granted Patent: US 9,043,637 B2
• Time in Patent Office: Days
• US Class Current: 714/4.11
• CPC Class Codes: G06F 11/1417 Boot up procedures
• CPC Class Codes: G06F 11/1464 for networked environments
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 11/1484 involving virtual machines
• CPC Class Codes: G06F 11/203 using migration
• CPC Class Codes: G06F 16/185 Hierarchical storage management [HSM] systems, e.g. file migration or policies thereof details of archiving G06F16/11
• CPC Class Codes: G06F 2201/84 Using snapshots, i.e. a logical point-in-time copy of the data
• CPC Class Codes: H04L 67/53 using third party service providers

Abstract

Services are promptly resumed at the time of a failure recovery in an information processing system. Before a first server system 3a resumes service during the failure recovery, a second server system 3b sends the first server system 3a directory images of directories of a highest-level tier to a predetermined lower-level tier out of data of files stored in a second storage apparatus 10b, and the first server system 3a restores the directory images in a first storage apparatus 10a. When the request is transmitted from the first server system 3a, the second server system 3b reads an additional directory image from the second storage apparatus 10b and transmits the additional directory image to the first server system 3a. If a re-stubbing occurrence frequency is equal to or higher than a predetermined threshold, the second server system 3b suppresses transmission of directory images to the first server system 3a.

Claims

1. A failure recovery method in an information processing system including

a first server system coupled to a first storage apparatus, and

a second server system coupled to the first server system and a second storage apparatus, wherein:

the first server system is configured to;

provide a first file system which creates a directory-configuration including metadata and entity data of files and data of hierarchical structured directories in the first storage apparatus;

receive and process an access request for each of the files of the directory-configuration; and

transmit the metadata and the entity data of files and the data of the directories of the directory-configuration stored in the first storage apparatus to the second server system;

the second server system is configured to;

provide a second file system related to the first file system; and

store the metadata and the entity data of the files and the data of the directories transmitted from the first server system in the second storage apparatus, the failure recovery method for recovering from a failure in the first server system comprising;

transmitting information of a root directory of the directory-configuration and information of directories in a first-level which is a next level of the root directory of the directory-configuration from the second server system to the first server system;

restoring a portion of the directory-configuration in the first storage apparatus by using the information of the root directory and the information of the directories in the first-level transmitted from the second server system before restarting receiving the access request;

restarting receiving the access request;

transmitting a metadata of a first file in a second-level which is a next level of the first-level from the second server system to the first server system if the metadata of the first file is not restored in the first storage apparatus when the first server system receives the access request for the first file; and

restoring a portion of the directory-configuration in the first storage apparatus by using the metadata of the first file and perform processing for the access request for the first file.

21. The failure recovery method according to the claim 1,

wherein the first file is in a first directory which is one of the directories in the first-level,

wherein in the case in which data of the first directory is not restored in the first storage apparatus, the failure recovery method further comprising:

the first server system obtaining the data of the first directory from the second server system and restoring a portion of the directory-configuration in the first storage apparatus by using the data of the first directory before obtaining the metadata of the first file from the second server system.

22. The failure recovery method according to the claim 21, the method further comprising:

the first server system obtaining entity data of the first file from the second server system if the entity data of the first file is not restored in the first storage apparatus when the first server system receives an I/O request for the first file and restoring a portion of the directory-configuration in the first storage apparatus by using the entity data of the first file.

23. The failure recovery method according to the claim 1, wherein the first server system does not obtain the information of directories in the second-level from the second server system when restarting receiving the access request.

24. The failure recovery method according to the claim 1, wherein the directory-configuration further includes data indicating hierarchical structure of the directories.

2-12. -12. (canceled)

13. An information processing system comprising:

a first server system coupled to a first storage apparatus; and

a second server system coupled to the first server system and a second storage apparatus, wherein;

the first server system is configured to;

provide a first file system which creates a directory-configuration including metadata and entity data of files and data of hierarchical structured directories in the first storage apparatus;

receive and process an access request for each of the files of the directory-configuration; and

transmit the metadata and the entity data of files and the data of the directories of the directory-configuration stored in the first storage apparatus to the second server system;

the second server system is configured to;

provide a second file system related to the first file system; and

store the metadata and the entity data of the files and the data of the directories transmitted from the first server system in the second storage apparatus;

in the case of failure recovery from a failure occurred in the first server system, the first server system is operable to;

obtain information of a root directory of the directory-configuration and information of directories in a first-level which is a next level of the root directory of the directory-configuration from the second server system;

restore a portion of the directory-configuration in the first storage apparatus by using the information of the root directory and the information of the directories in the first-level obtained from the second server system before restarting receiving the access request;

obtain a metadata of a first file in a second-level which is a next level of the first-level from the second server system to the first server system if the metadata of the first file is not restored in the first storage apparatus when the first server system receives the access request for the first file; and

restore a portion of the directory-configuration in the first storage apparatus by using the metadata of the first file and perform processing for the access request for the first file.

25. The information processing system according to the claim 13,

wherein the first file is in a first directory which is one of the directories in the first-level,

wherein in the case in which data of the first directory is not restored in the first storage apparatus,

the first server system obtains the data of the first directory from the second server system and restores a portion of the directory-configuration in the first storage apparatus by using the data of the first directory before obtaining the metadata of the first file from the second server system.

26. The information processing system according to the claim 25,

wherein the first server system obtains entity data of the first file from the second server system if the entity data of the first file is not restored in the first storage apparatus when the first server system receives an I/O request for the first file and restores a portion of the directory-configuration in the first storage apparatus by using the entity data of the first file.

27. The information processing system according to the claim 13,

wherein the first server system does not obtain the information of directories in the second-level from the second server system when restarting receiving the access request.

28. The information processing system according to the claim 13,

wherein the directory-configuration further includes data indicating hierarchical structure of the directories.

14-15. -15. (canceled)

16. A file server system which includes a first server system coupled to a first storage apparatus and a second server system which provides a second file system and is coupled to a second storage apparatus for storing data the second server system receives, wherein

the file server system is configured to:

provide a first file system which creates a directory-configuration including metadata and entity data of files and data of hierarchical structured directories in the first storage apparatus;

receive and process an access request for each of the files of the directory-configuration; and

transmit the metadata and the entity data of the files and the data of the directories of the directory-configuration stored in the first storage apparatus to the second server system, and

in the case of failure recovery from a failure occurred in the file server system, the file server system is operable to;

obtain information of a root directory of the directory-configuration and information of directories in a first-level which is a next level of the root directory of the directory-configuration from the second server system;

restore a portion of the directory-configuration in the first storage apparatus by using the information of the root directory and the information of the directories in the first-level obtained from the second server system before restarting receiving the access request;

obtain a metadata of a first file in a second-level which is a next level of the first-level from the second server system if the metadata of the first file is not restored in the first storage apparatus when the first server system receives the access request for the first file; and

restore a portion of the directory-configuration in the first storage apparatus by using the metadata of the first file and perform processing for the access request for the first file.

17. The file server system according to the claim 16,

wherein the first file is in a first directory which is one of the directories in the first-level,

wherein in the case in which data of the first directory is not restored in the first storage apparatus,

the file server system obtains the data of the first directory from the second server system and restores a portion of the directory-configuration in the first storage apparatus by using the data of the first directory before obtaining the metadata of the first file from the second server system.

18. The file server system according to the claim 16, wherein the file server system obtains entity data of the first file from the second server system if the entity data of the first file is not restored in the first storage apparatus when the file server system receives an I/O request for the first file and restores a portion of the directory-configuration in the first storage apparatus by using the entity data of the first file.

19. The file server system according to the claim 18,

wherein the file server system does not obtain the information of directories in the second-level from the second server system when restarting receiving the access request.

20. The file server system according to the claim 18,

wherein the directory-configuration further includes data indicating hierarchical structure of the directories.