Storage medium management device, storage medium management method, and storage medium management program

Abstract

To precisely predict a storage medium with a high failure risk and reduce a rebuilding time.SOLUTION: An HDD information collecting unit 211 collects the operational state of a plurality of physical disks HDD1 to HDD3 forming an RAID array. A statics information analysis unit 212 determines whether there is a relative difference in the operational state of the collected physical disks HDD1 to HDD3. A failure HDD prediction unit 213 predicts a physical disk with the highest failure risk on the basis of the relative difference in the operational state. An HDD copy control unit 214 copies the data of the physical disk predicted to have the highest failure risk into a standby disk SHDD.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a storage media management device, a storage media management method, and a storage media management program. [Background technology]

[0002] In recent years, in RAID (Redundant Arrays of Inexpensive Disks, or Redundant Arrays of Independent Disks) systems, as the capacity of physical disks increases, when a physical disk fails, a RAID rebuild (reconstruction) process takes a lot of time. In order to shorten the rebuild process time, a technique has been proposed in which data is sequentially copied to a spare disk while specifying the address range of a suspected disk device during the access free time from a device in a recovery mode setting that has been determined to be a suspected disk device when an error statistical value exceeds a predetermined threshold (for example, Patent Document 1). The rebuild process refers to a process in which, when a RAID system is constructed and operated using physical disks such as multiple HDDs, and a disk fails in the RAID system, data in the failed disk is restored and reconstructed from other non-failed HDDs. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-139339 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the method of Patent Document 1, an addition value is set in advance for various types of failures of a disk device (storage medium), such as a motor stop, a medium defect error, a mode error, etc., and the corresponding addition value for each occurrence of an error is set as an error statistics addition value, and a disk device whose error statistics addition value exceeds a predetermined threshold is identified as a suspected disk device. However, just because the error statistics addition value exceeds a predetermined threshold does not necessarily mean that the suspected disk device will fail in the future. Therefore, there is a problem that it is not possible to accurately identify disk devices that are at high risk of failing in the future, and other disk devices may fail, resulting in a long time required for the rebuild process.

[0005] Therefore, an object of the present invention is to provide a storage media management device, a storage media management method, and a storage media management program that can more accurately predict storage media with a high risk of failure and reduce the rebuild time. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, one aspect of the present invention is characterized by comprising a collection means for collecting the operating statuses of multiple storage media that constitute a RAID array, an operating status judgment means for judging whether there is a relative difference in the operating statuses of the multiple storage media collected by the collection means, a prediction means for predicting the storage medium with the highest risk of failure based on the judgment result by the operating status judgment means, and a copy control means for copying data of the storage medium with the highest risk of failure predicted by the prediction means to a standby storage medium.

[0007] Moreover, one aspect of the present invention is a storage media management method for managing a plurality of storage media that constitute a RAID array, comprising the steps of: collecting operating statuses of the plurality of storage media; determining whether there is a relative difference in the collected operating statuses of the plurality of storage media; predicting a storage medium having the highest risk of failure based on the result of the determination; and copying data of the predicted storage medium having the highest risk of failure to a standby storage medium.

[0008] Furthermore, one aspect of the present invention is characterized in that a computer of a storage media management device that manages multiple storage media that make up a RAID array is made to execute the steps of collecting operating statuses of the multiple storage media, determining whether there is a relative difference in the collected operating statuses of the multiple storage media, predicting a storage medium with the highest risk of failure based on the result of the determination, and copying data of the predicted storage medium with the highest risk of failure to a standby storage medium. Effect of the Invention

[0009] As described above, the advantage is obtained that the storage media with a high risk of failure can be predicted more accurately and the rebuild time can be shortened. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a configuration of a server system to which a RAID controller (storage media management device) 20 according to an embodiment of the present invention is applied. [Diagram 2] 5 is a flowchart for explaining an operation that is periodically executed by the RAID controller 20 according to the present embodiment. [Diagram 3] 4 is a flowchart for explaining normal operation of the RAID controller 20 according to the present embodiment. [Figure 4] 2 is a schematic diagram showing a disk control operation by the RAID controller 20 according to the present embodiment. FIG. [Diagram 5] 2 is a schematic diagram showing a disk control operation by the RAID controller 20 according to the present embodiment. FIG. [Figure 6] 2 is a schematic diagram showing a disk control operation by the RAID controller 20 according to the present embodiment. FIG. [Figure 7] 2 is a schematic diagram showing a disk control operation by the RAID controller 20 according to the present embodiment. FIG. [Figure 8] 2 is a schematic diagram showing a disk control operation by the RAID controller 20 according to the present embodiment. FIG. [Figure 9] 2 is a schematic diagram showing a disk control operation by the RAID controller 20 according to the present embodiment. FIG. [Figure 10] 2 is a schematic diagram showing a disk control operation by the RAID controller 20 according to the present embodiment. FIG. [Figure 11] FIG. 2 is a block diagram showing a minimum configuration of a storage media management device according to the present embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0012] A. Embodiment 1 is a block diagram showing the configuration of a server system to which a RAID controller (storage media management device) according to this embodiment is applied. The server system 1 is composed of an OS (Operating System) 10, a RAID controller 20, and a disk array 30. The OS 10 is made up of a RAID driver 11 and a RAID management utility 12. The RAID driver 11 is software for transmitting and receiving (reading / writing) data to and from the disk array 30. The RAID management utility 12 is software used to manage reading and writing data to and from the disk array 30 at the OS level.

[0013] The RAID controller 20 includes RAID firmware 21, which includes an HDD information collection unit 211, a statistical information analysis unit 212, a failed HDD prediction unit 213, and an HDD copy control unit 214. The disk array 30 has physical disks HDD1, HDD2, HDD3, and a standby disk SHDD that configure RAID5. RAID5 is a technology that manages a plurality of external storage devices (such as hard disks) as a single device. In this embodiment, the physical disks HDD1, HDD2, HDD3, and the standby disk SHDD are assumed to be hard disks, but are not limited to this and may be semiconductor storage media such as SSDs (Solid State Drives).

[0014] The HDD information collection unit 211 periodically collects statistical information of each of the physical disks HDD1 to HDD3 of the disk array 30. The statistical information is information indicating at least one operating state such as operating time, response speed, error rate, and number of registered substitute sectors. The statistical information analysis unit 212 analyzes the collected statistical information including at least one operating state such as operating time, response speed, error rate, and number of registered substitute sectors of the physical disks HDD1 to HDD3. The analysis method will be described later.

[0015] The failure HDD prediction unit 213 identifies an HDDm (m=1, 2, or 3) that has the highest risk of failure in the future from among the multiple physical disks HDD1 to HDD3 connected to the RAID controller 20, based on the analysis result of the statistical information of the physical disks HDD1 to HDD3 analyzed by the statistical information analysis unit 212. The HDD copy control unit 214 copies data of the identified HDDm that has the highest risk of failure in the future to the standby disk SHDD.

[0016] B. Operation of the embodiment Fig. 2 is a flow chart for explaining the operation periodically executed by the RAID controller 20 according to this embodiment. Fig. 4 to Fig. 6 are schematic diagrams showing the disk control operation by the RAID controller 20 according to this embodiment.

[0017] The flowchart shown in FIG. 2 is executed periodically (for example, once a week). The HDD information collecting unit 211 collects statistical information such as the operating time, response speed, error rate, and number of registered substitute sectors of each physical disk HDD1 to HDD3 of the disk array 30 (step S10). The statistical information analyzing unit 212 analyzes the collected statistical information indicating the operating time, response speed, error rate, and number of registered substitute sectors of the physical disks HDD1 to HDD3, and judges whether or not there is a difference in the operating state of the physical disks HDD1 to HDD3 that is sufficient to predict the risk of failure in the future (step S12). For example, the statistical information of the physical disks HDD1 to HDD3 that are members constituting a logical drive is analyzed, and it is judged whether or not there is a relative difference (a difference indicating deterioration) in at least one operating state with respect to other physical disks, such as a slightly long operating time, a slow response speed, a large error rate, or a large number of registered substitute sectors.

[0018] Then, if there is no difference in at least one of the operational states included in the collected statistical information of each of the physical disks HDD1 to HDD3 (NO in step S14), the HDD copy control unit 214 selects an arbitrary physical hard disk HDDn (n=1, 2, or 3) (for example, HDD2) and copies the data of the physical hard disk HDDn to the standby disk SHDD (step S16). For example, as shown in FIG. 4, the physical disk HDD2 is selected and the data of the physical disk HDD2 is copied to the standby disk SHDD. Then, the process ends.

[0019] On the other hand, if there is a difference in at least one operating state included in the collected statistical information of each of the physical disks HDD1 to HDD3 that is sufficient to predict the risk of a future failure (YES in step S14), the failure HDD prediction unit 213 identifies the physical disk HDDm (m=1, 2, or 3) that has the highest risk of future failure from among the multiple physical disks HDD1 to HDD3 connected to the RAID controller 20 based on the analysis results analyzed by the statistical information analysis unit 212, i.e., the relative difference in at least one operating state (operating time, response speed, error rate, number of registered replacement sectors, etc.) of the physical disks HDD1 to HDD3 (step S18).

[0020] For example, the failure HDD prediction unit 213 identifies a physical hard disk having a relative difference in at least one operation state from other physical disks, such as a slightly longer operation time, a slower response speed, a larger error rate, a larger number of substitute sectors registered, etc., from among the physical disks HDD1 to HDD3 that are members constituting the logical drive, as the physical disk HDDm having the highest risk of failure. For example, as shown in Fig. 5, when the physical disk HDD2 has a difference from other physical disks, such as a slightly longer operation time, a slower response speed, or a larger number of substitute sectors registered, the physical disk HDD2 is identified as the physical disk HDDm predicted to have the highest risk of failure in the future.

[0021] For "slight", a threshold value may be set in advance for the "difference", and if the threshold value is exceeded, the physical disk may be predicted as the physical disk HDDm with the highest risk of failure in the future. In addition, regarding which of the operating conditions among the operating time, response speed, and number of registered substitute sectors is used for the judgment, each operating condition may be weighted or a priority may be set. In addition, at least one of the operating time, response speed, and number of registered substitute sectors may be used as the judgment condition, or two or more of them may be combined to be used as the judgment condition.

[0022] Next, the failure HDD prediction unit 213 judges whether the currently identified high-risk physical disk HDDm has a higher failure risk than the previously identified high-risk physical disk HDDp (p=1, 2, or 3) (step S20). Whether the failure risk is high or low may be judged based on the magnitude of each of the operating time, response speed, number of registered substitute sectors, etc. Then, if the currently identified high-risk physical disk HDDm has a lower failure risk than the previously identified high-risk physical disk HDDp (NO in step S20), the process ends without doing anything.

[0023] On the other hand, if the currently identified physical disk HDDm with a high risk of failure has a higher failure risk than the previously identified physical disk HDDp with a high risk of failure (YES in step S20), the HDD copy control unit 214 copies the data of the currently identified physical disk HDDm with the highest risk of failure to the standby disk SHDD (step S22).

[0024] For example, if the physical disk HDD3 is currently identified as the physical disk HDDm with a high risk of failure, and the failure risk of this physical disk HDD3 is higher than that of the previously identified physical disk HDD2 with a high risk of failure due to factors such as a long operating time, a slow response speed, a large number of registered substitute sectors, etc., then the physical disk HDD2 is switched to the physical disk HDD3, and data of the currently identified physical disk HDD3 with the highest risk of failure is copied to the standby disk SHDD, as shown in Fig. 6. Then, the process is terminated.

[0025] Fig. 3 is a flowchart for explaining the normal operation of the RAID controller 20 according to this embodiment. Also, Figs. 7 to 10 are schematic diagrams showing the disk control operation by the RAID controller 20 according to this embodiment.

[0026] The flowchart shown in Fig. 3 is executed when a write request is received from the upper OS 10, an application, etc. In the RAID controller 20, when a write request is received from the upper OS 10, an application, etc., the HDD copy control unit 214 writes data to the physical disk HDDm identified as having a high risk of failure, and also writes the same data to the standby disk SHDD (step S30). For example, when the physical disk with the highest risk of failure is the physical disk HDD2, as shown in Fig. 7, data is written to the physical disk HDD2, and also written to the standby disk SHDD.

[0027] Next, the RAID controller 20 judges whether or not the physical disk HDDm identified as having a high risk of failure has actually failed (step S32). If the physical disk HDDm identified as having a high risk of failure has not yet failed (NO in step S32), the RAID controller 20 ends the process without taking any action.

[0028] On the other hand, if the physical disk HDDm identified as having a high risk of failure actually fails (YES in step S32), the RAID controller 20 separates the failed physical disk HDDm and incorporates the standby disk SHDD, in which the same data as that of the failed physical disk HDDm was written, into the hard disk device (RAID) (step S34). For example, as shown in FIG. 8, if the physical disk HDD2 identified as having a high risk of failure actually fails, the failed physical disk HDD2 is separated, and the standby disk SHDD, in which the same data as that of the failed physical disk HDD2 was written, is incorporated into the RAID as the physical disk HDD2. Therefore, a rebuild operation is not required, and the occurrence of a system down or data loss can be prevented. Then, the process ends.

[0029] If a physical disk other than the physical disk HDD2 predicted by the failure HDD prediction unit 213 to have a high failure risk, for example, the physical disk HDD1, fails, an operation of writing data from the remaining physical disks HDD2 and HDD3 to the standby disk SHDD, that is, a so-called rebuild process, is performed as shown in Fig. 9. In this case, a rebuild process is required.

[0030] However, as described above, in this embodiment, a physical hard disk that has at least one relative difference in operation state from other physical disks, such as a slightly long operating time, a slow response speed, a large error rate, a large number of replacement sectors registered, etc., is identified as the physical disk HDDm with the highest risk of failure. Therefore, according to this embodiment, compared to a method that uses simply exceeding a uniquely set threshold as a criterion, it is possible to more accurately predict the physical disk HDDm with the highest risk of failure in the future, and therefore a situation requiring a rebuild process is less likely to occur.

[0031] When the failed physical disk HDD2 is replaced with a new physical disk HDD2new, the physical disk HDD2new is automatically set as the standby disk SHDD as shown in Fig. 10. After the setting of the standby disk SHDD is completed, the RAID controller 20 executes the flowchart shown in Fig. 2, identifies the physical disk HDDm that has the highest risk of failure in the future from among the physical disks HDD1 to HDD3, and copies data to the standby disk SHDD (HDD2new).

[0032] According to the above-described embodiment, a physical hard disk having at least one relative difference in operation state from other physical disks, such as a slightly long operating time, a slow response speed, a large number of substitute sectors registered, etc., is identified as the physical disk HDDm having the highest risk of failure, so that it is possible to more accurately predict the physical disk having the highest risk of failure in the future. Furthermore, by copying data of the physical disk HDDm having the highest risk of failure to the standby disk SHDD before the failure, even if the physical disk actually fails, the standby disk SHDD is incorporated into the RAID by switching to the failed physical disk, so that the rebuild time can be shortened.

[0033] FIG. 11 is a block diagram showing the minimum configuration of a storage media management device according to this embodiment. The storage media management device 50 according to this embodiment may include at least a plurality of storage media 52-54 constituting a RAID array 51, a standby storage medium 55, a collection means 56, an operation state determination means 57, a prediction means 58, and a copy control means 59. The plurality of storage media 52-54 constitute a RAID array (RAID5). The collection means 56 collects the operation states of the plurality of storage media 52-54. The operation state determination means 57 determines whether there is a relative difference in the operation states of the plurality of storage media 52-54 collected. The prediction means 58 predicts the storage medium with the highest failure risk based on the determination result by the operation state determination means 57. The copy control means 59 copies data of the storage medium with the highest failure risk predicted by the prediction means 58 to the standby storage medium 55.

[0034] In addition, a program for realizing the functions of the processing unit in the present invention may be recorded in a computer-readable recording medium, and the program recorded in the recording medium may be read into a computer system and executed to control the bonus information. In addition, the term "computer system" as used herein includes hardware such as an OS and peripheral devices. In addition, the term "computer system" may include a plurality of computer devices connected via a network including the Internet, a WAN, a LAN, a dedicated line, and other communication lines. In addition, the term "computer-readable recording medium" refers to portable media such as a flexible disk, an optical magnetic disk, a ROM, a CD-ROM, and a storage device such as a hard disk built into a computer system. Furthermore, the term "computer-readable recording medium" refers to a storage device that holds a program for a certain period of time, such as a volatile memory (RAM) inside a computer system that becomes a server or a client when a program is transmitted via a network. In addition, the above program may be for realizing part of the above-mentioned functions. Furthermore, the above-mentioned functions may be realized in combination with a program already recorded in the computer system, that is, a so-called difference file (difference program).

[0035] In addition, some or all of the above-mentioned functions may be realized as an integrated circuit such as LSI (Large Scale Integration). Each of the above-mentioned functions may be individually implemented as a processor, or some or all of the functions may be integrated into a processor. The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, if an integrated circuit technology that can replace LSI appears due to advances in semiconductor technology, an integrated circuit based on that technology may be used. [Explanation of symbols]

[0036] 1. Server System 10 OS 11 RAID Driver 12 RAID Management Utilities 20 RAID Controller 21 RAID Firmware 211 HDD Information Collection Department 212 Statistical Information Analysis Department 213 HDD Failure Prediction Department 214 HDD copy control unit 30 Disk Array HDD1~HDD3 Physical disks SHDD Standby Disk

Claims

1. A collection means for collecting operating states of a plurality of storage media constituting a RAID array; an operational status determination means for determining whether or not there is a relative difference between the operational statuses of the plurality of storage media collected by the collection means, rather than determining whether each operational status exceeds a preset threshold; a predicting means for predicting a storage medium having the highest risk of failure based on a result of the judgment by the operating state judging means; a copy control means for copying data of the storage medium having the highest failure risk predicted by the prediction means to a standby storage medium; Equipped with the copy control means, when the operation state determination means determines that there is no difference in the operation state, copies data of an arbitrary storage medium among the plurality of storage media to the standby storage medium; said copy control means, when it is determined that there is a difference in the operating state and the storage medium predicted to have the highest failure risk is different from the previous time, copies data of the storage medium predicted to have the highest failure risk to said standby storage medium; When a data write request is received, the copy control means writes the data to the storage medium having the highest predicted failure risk, and also writes the same data to the standby storage medium. A storage medium management device comprising:

2. The storage media management device according to claim 1, characterized in that, when the storage medium with the highest risk of failure fails, the copy control means replaces the storage medium with the highest risk of failure and incorporates the standby storage medium as one of the multiple storage media.

3. 3. The storage media management device according to claim 1, wherein the operation status includes at least one of an operating time, a response speed, an error rate, and a number of registered alternative sectors for each of the plurality of storage media.

4. A storage media management method in a computer of a storage media management device that manages a plurality of storage media constituting a RAID array, comprising: a collection means for collecting information on the operation states of the plurality of storage media in the storage media management device; a step in which an operational status determination means of the storage media management device determines whether or not there is a relative difference in the operational statuses of the plurality of storage media collected, rather than determining whether each operational status exceeds a preset threshold value; a step of predicting a storage medium having the highest risk of failure based on a result of the judgment by a prediction means of the storage medium management device; a step of a copy control means of the storage medium management device copying data of the storage medium having the predicted highest failure risk to a standby storage medium; a copy control means of the storage media management device copying data of an arbitrary storage medium among the plurality of storage media to the standby storage medium when the operation state determination means determines that there is no difference in operation state; a step of a copy control means of the storage medium management device, when it is determined that there is a difference in the operating state and the storage medium predicted to have the highest failure risk is different from the previous time, copying data of the storage medium currently predicted to have the highest failure risk to the standby storage medium; a copy control means of the storage medium management device, when receiving a request to write data, writing the data to the storage medium having the highest predicted failure risk and writing the same data to the standby storage medium; 13. A storage medium management method comprising:

5. A computer of a storage media management device that manages a plurality of storage media constituting a RAID array, collecting operational status of the plurality of storage media; determining whether or not there is a relative difference between the collected operational states of the plurality of storage media, rather than determining whether each operational state exceeds a preset threshold; predicting a storage medium having the highest risk of failure based on the result of the determination; copying data of the storage medium having the highest predicted risk of failure to a standby storage medium; copying data of an arbitrary storage medium among the plurality of storage media to the standby storage medium when it is determined that there is no difference in the operational state; copying data of the storage medium currently predicted to have the highest risk of failure to the standby storage medium when it is determined that there is a difference in the operating state and the storage medium currently predicted to have the highest risk of failure is different from that previously predicted; when a data write request is received, writing the data to the storage medium having the highest predicted failure risk and writing the same data to the standby storage medium; A storage medium management program for causing a user to execute the above steps.

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