JPH0962460A - Information processing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability of a disk array device by restructuring a RAID by using normal disk devices except a disk where a fault has occurred and putting saved information back to the disk array device after the restructuring. SOLUTION: When an abnormality detection flag 33 and a disk replacement flag 37 become effective, a scheduler 11 alters RAID constitution in intervals of operation. Namely, a control part 32 performs a process for backing up the information on the disk array device 3 to an external storage device 4 and makes a saving end flag 34 effective at the end of the saving operation. At this time, the data are compressed so that the amount of the information is less than the storage capacity of the device 3 after the alteration into (n-1)- disk RAID constitution. Then the control part 32 detects a data compressible flag 35 becoming valid, changes the RAID constitution from (n) disk devices to (n-1) disk devices, and puts the information saved on the external storage device 4 back to the disk array device 3 once the alteration of the RAID is completed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing system, and more particularly to a RAID (Redundant
Arrays of Inexpnsive disks) The technology is effective when applied to an information processing system including a disk array device configured.

[0002]

2. Description of the Related Art Conventionally, n disk units have been used for R
In an information processing system including a disk array device forming an AID, data and information about the data are distributed and stored in n disk devices.

As a result, when a failure occurs in one of the disk devices constituting the RAID, the remaining n-1 disks operating normally are stored in the failed disk device. A degenerate operation is performed in which data is constructed to supplement the information stored in the failed disk device.

Conventionally, the RAID configuration has been set by the user when the system was constructed, and could not be changed thereafter.

As such a device, for example, Japanese Unexamined Patent Application Publication No.
A configurable redundant array storage device disclosed in Japanese Patent Laid-Open No. 197498 is cited.

[0006]

SUMMARY OF THE INVENTION As a result of studying the above prior art, the present inventor has found the following problems.

In the above-described conventional configurable redundant array storage device, since the RAID configuration once set cannot be changed, if a failure occurs in another disk device during degenerate operation, data cannot be reproduced. Therefore, there is a problem that the reliability of the disk array device is low.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a technique capable of improving the reliability of a disk array device in an information system.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

[0010]

SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.

An information processing apparatus that performs information processing and a RAID system that is connected to the information processing apparatus and includes a plurality of disk devices.
A disk array device that is configured and controlled, and an external storage device that backs up the information of the disk array device,
An information processing system comprising means for performing degenerate operation when a failure occurs in the RAID configured disk device, wherein means for backing up information of the disk array device to the external storage device during the degenerate operation, It is provided with means for disconnecting a disk device in which a failure has occurred during degenerate operation to build a RAID configuration with the remaining disk device, and means for writing information backed up in the external storage device to the built disk array device.

[0012]

According to the above-mentioned means, when a failure occurs in the disk device constituting the RAID, the information of the disk is temporarily saved in another external storage device, and the remaining normal except for the disk in which the failure has occurred. With a simple disk device
By rebuilding the AID and returning the saved information to the disk array device after the rebuilding, even if a failure occurs in the disk device after the rebuilding, the information of the remaining normal disk device is used. In addition, since the data can be reproduced and the failure of another disk device can be prepared, the reliability of the disk array device can be improved.

The present invention will be described below with reference to examples.

In all the drawings for explaining the embodiments, those having the same function are designated by the same reference numerals, and the repeated description thereof will be omitted.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram for explaining the configuration of an information processing system which is an embodiment of the present invention.

In FIG. 1, the information processing system of the present embodiment is a scheduler 1 for managing operations in information processing.
A server 1 having 1; clients 21 to 2n; a disk array device 3 configured as a storage device with a RAID of n disk devices; and an external storage device 4 for backing up information of the disk array device. Composed of.

The disk array device 3 also includes a controller 32 for controlling the disk array controller board 31.
The disk array controller board 31 includes an abnormality detection flag 33, a save end flag 34, a data compressible flag 35, a data incompressible flag 36, and a disk exchange flag 37.

The abnormality detection flag 33 is a flag which becomes effective when one of the disk devices constituting the RAID fails, and the disk replacement flag 37 is effective when the failed disk device is replaced. It is a flag that becomes.

When the abnormality detection flag 33 and the disk replacement flag 37 become valid, the scheduler 11 which manages the operation of the information processing system of this embodiment waits for the operation (for example, immediately after power-off after the end of work). To RAI
The change processing of the D configuration is performed.

When the RAID change process is activated by the scheduler 11, the control unit 32 performs a process for backing up the information of the disk array device to the external storage device 4, and when the save is completed, the save end flag 34 is set. Validate.

At this time, data compression is performed so that the amount of information is contained in the storage capacity of the disk array device after the RAID configuration is changed to n-1 units, and if data compression is possible, the data compression possible flag 35 is set. If the data compression is impossible, the data compression impossible flag 36 is made valid.

The control unit 32 controls the data compressible flag 35.
Is detected, the RAID configuration is changed from n disk units to n-1 disk units, and
When the ID change is completed, the information saved in the external storage device is returned to the disk array device.

Next, in the above-described information processing system of this embodiment, the control operation when the information of the disk array device 3 can be compressed at the time of failure and when it cannot be compressed will be described.

FIG. 2 is a time chart showing the transition of the control operation of the information processing system of this embodiment when the information of the disk array device 3 can be compressed at the time of failure.

When a failure occurs in one of the n disk devices constituting the RAID, the controller 32 of the disk array controller board 31 detects the disk failure,
As shown in FIG. 2B, the abnormality occurrence flag 7 is made valid.

When the abnormality detection flag 33 becomes valid, the scheduler 11 which manages the operation of the system operates as shown in FIG.
As shown in (a), a RAID change process is executed between operations.

In the RAID changing process, first, a process for saving the information in the disk array device 3 to the external storage device 4 is performed, and when the data backup is completed, as shown in FIG. The save end flag 34 is validated.

At this time, the data compression is performed so that the information amount can be stored in the storage capacity of the disk array device 3 after the RAID configuration of n-1 units is changed. ), The data compressible flag 3
5 is valid.

At the time when the data compressible flag 35 becomes valid, the control unit 32, as shown in FIG.
A process of changing the ID configuration from n units to n-1 units is performed.

When the disk array device 3 is changed to a RAID configuration with n-1 disk devices, FIG.
As shown in (3), the information saved in the external storage device is returned to the disk array device 3.

When the data recovery process for the disk array device 3 is completed, as shown in FIGS. 2B to 2D, the abnormality occurrence flag 7, the data compressible flag 35, and the save completion flag 34 are set. Invalidate.

FIG. 3 is a time chart showing the transition of the control operation of the information processing system of this embodiment when the information of the disk array device 3 cannot be compressed at the time of failure.

As shown in FIG. 3 (g), when the processing for saving the information in the disk array device 3 to the external storage device 4 is performed, the control unit 32 causes the RAID to have an information amount of n-1.
Data compression is performed so that the storage capacity of the disk array device after the configuration is changed is set. However, when data compression is not possible, the data compression impossible flag 36 is enabled as shown in FIG. And

When the data uncompressible flag 36 becomes valid, the control section 32 continues to operate in the degenerate state as shown in FIG.

FIG. 4 is a time chart showing the transition of the control operation of the information processing system of this embodiment when the failed disk device is replaced with a normal disk device.

When a failed disk device is replaced,
The control unit 32 detects that the abnormal disk device is replaced with a normal disk device, and as shown in FIG.
The disk exchange flag 37 is validated.

When the disk exchange flag 37 becomes valid,
The scheduler 11, which manages the operation of the system, executes a RAID change process between operations.

In the RAID changing process, first, FIG.
As shown in FIG. 4, processing for saving the information in the disk array device 3 to the external storage device 4 is performed, and when the data saving is completed, the save end flag 34 is enabled as shown in FIG. Then, as shown in FIG. 4A, the control unit 32 performs a process of changing the RAID configuration from n-1 units to n units.

When the disk array device 3 is changed to a RAID configuration with n disk devices, the control unit 32
As shown in FIG. 4G, a process of returning the information saved in the external storage device 4 to the disk array device 3 is performed.

When the data recovery process for the disk array device 3 is completed, the disk replacement flag 11 shown in FIG. 4 (e) and the save end flag 34 shown in FIG. 4 (c) are invalidated.

FIG. 5 is a flow chart showing the control procedure of the disk array device 3 in the information processing system of this embodiment.

In the information processing system of the present embodiment, the abnormality detection flag 3 indicating that a failure has occurred in one of the n disk devices that make up the disk array control RAID
When 3 is valid, the scheduler 11 performing operation management causes the processing of RAID change to be performed between jobs.

In the RAID changing process, first, the disk device in which the failure has occurred is disconnected in step 121,
It is determined whether or not RAID configuration is possible with n-1 disk devices.

If the RAID configuration is not possible with n-1 disk devices, the fact that the RAID configuration cannot be changed is displayed on the display (step 125), and the degenerate operation is performed (step 126).

When the RAID configuration is possible with n-1 disk devices, the information in the disk array device 3 is compressed and saved in the external storage device 4 (step 12).
2).

In step 124, it is judged whether the data compression impossible flag 36 which is effective when the data compression is impossible is effective. If it is effective, it is displayed that the RAID configuration cannot be changed. (Step 125) and the disk array device 3 performs degenerate operation (step 126).

When data compression is possible and the valid data compression possible flag 35 is valid, the RAID configuration is changed from n to n-1 disk devices (step 127), and the RAID configuration is changed. When the change is completed, the information of the disk array device saved in the external storage device 4 is returned to the disk array device 3 (step 128).

After returning the information to the disk array device 3, the abnormality detection flag 33, the data compressible flag 35,
The evacuation end flag 34 is invalidated (step 129), and normal operation is performed (step 130).

FIG. 6 is a flow chart showing the control procedure of the disk array device 3 when replacing the failed disk device in the information processing system of this embodiment.

When the disk replacement flag 37, which indicates that the failed disk device has been replaced with a normal disk device, is valid, the scheduler 11 performing operation management causes the RAID change process to be performed between jobs.

In the RAID changing process, first, the information of the disk array device 3 is saved in the external storage device 4 (step 131), and the RAID configuration is changed from n-1 to n disk devices ( At step 133), when the RAID change is completed, the information of the disk array device 3 saved in the external storage device 4 is returned to the disk array device 3 (step 134).

After the information is returned to the disk array device 3, the disk replacement flag 37 and the save end flag 34 are invalidated (step 135), and normal operation is performed (step 136).

Therefore, in the information processing system of the present invention, when a failure occurs in one disk device constituting the RAID, the RAID is rebuilt except for the failed disk device, and another one is rebuilt after the RAID rebuilding. Even if one of the disk devices becomes a failure, the information stored in the disk array device is valid, so that it is possible to reproduce the data. Similarly, by reconstructing the RAID, the data of another disk device can be reproduced. Since it is possible to prepare for the occurrence of a failure, the reliability of the disk array device in the information system can be improved.

As described above, the invention made by the present inventor is:
Although the present invention has been specifically described based on the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the scope of the invention.

[0055]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

It is possible to improve the reliability of the disk array device in the information system.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a configuration of an information processing system that is an embodiment of the present invention.

FIG. 2 is a time chart showing a transition of control operation of the information processing system of the present embodiment when information of the disk array device 3 can be compressed at the time of failure.

FIG. 3 is a time chart showing the transition of the control operation of the information processing system of the present embodiment when the information of the disk array device 3 cannot be compressed at the time of failure.

FIG. 4 is a time chart showing a transition of control operation of the information processing system of the present embodiment when a failed disk device is replaced with a normal disk device.

FIG. 5 is a flowchart showing a control procedure of the disk array device 3 in the information processing system of this embodiment.

FIG. 6 is a flowchart showing a control procedure of the disk array device 3 when replacing a failed disk device in the information processing system according to the present embodiment.

[Explanation of symbols]

1 ... Server, 3 ... Disk array, 4 ... External storage device,
11 ... Scheduler, 21-2n ... Client, 31
... Disk array controller board, 32 ... Controller,
33 ... Abnormality detection flag, 34 ... Evacuation end flag, 35 ...
Data compressible flag, 36 ... Data uncompressible flag, 37 ... Disk exchange flag.

Claims (1)

[Claims] 1. An information processing apparatus for performing information processing, and a plurality of disk devices connected to the information processing apparatus, the RAI.
An information processing system comprising a disk array device configured and controlled D, an external storage device that backs up information of the disk array device, and means for performing degenerate operation when a failure occurs in the RAID configured disk device. A means for backing up the information of the disk array device to the external storage device during the degenerate operation; a means for disconnecting the disk device in which the failure has occurred during the degenerate operation and for constructing a RAID configuration with the remaining disk devices; An information processing system comprising: means for writing the information backed up in the external storage device to the constructed disk array device.