JPH11327804A - Disk duplexing system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disk duplexing system which can restore a simplex operation of a duplex disk even if a fault occurs in the disk device during the simplex operation of the duplex disk. SOLUTION: When a fault occurs in a disk device during a simplex operation, a disk duplex control means 11 restores the operation state of a duplex disk where the fault occurs in the disk device during the simplex operation in duplex disks 50 and 60. When the state is not restored even if the operation is repeated for several times, a system is automatically switched to the operation in a other disk device which is not used in the simplex operation, and an emergency operation for restoring the operation is executed. A disk time display means 12 displays and outputs time information which is read from the disk device selected for restoration in the emergency operation to an input/output part 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a disk duplication system, and more particularly to a disk duplication system for controlling the operation of a duplicate disk composed of two disk devices.

[0002]

2. Description of the Related Art Conventionally, there has been known a disk duplication system including a replaceable hard disk (Japanese Patent Laid-Open No. Hei 8-44501). This conventional disk duplication system includes a disk data coincidence determination unit, a disk mounting change detection and recognition unit, a configuration control unit for controlling a disk configuration change, a disk removal request unit, and an LE
It has D control means, and selects a disk device to be used for a duplex disk at the time of system startup according to the flowchart of FIG.

That is, in this conventional disk duplex system, when the system is started, the disk management information of both systems is read out (step 101), and both disk states are connected and whether the matching information matches. It is determined whether or not these conditions are satisfied (steps 102 and 103). Even if both disk states are connected (step 102), if it is determined in step 103 that the matching information does not match, both systems are disconnected.

When it is determined in step 102 that both disk states are not connected, it is determined whether both disk states are disconnected (step 10).
4) If both disk states are not in the detached state, the system is operated as one of the systems in the connected state. Further, when it is determined in step 104 that both disk states are in the separated state, the system is operated with both systems separated.

Further, in a general conventional disk duplexing system, the state of the duplexed disk before the system is started is read, the operation of the duplicated disk is restored according to the read result, and the data of the duplicated disk is always updated. Has become. In the conventional disk duplication system described in the above-mentioned publication, when the coincidence information does not match, both systems are separated from each other, and there is no problem even if the duplicated disk cannot be used.

On the other hand, in a system such as an exchange or a non-stop computer, which requires a non-stop duplex disk, even if the matching information does not match, the duplex is faithful to the state of the duplex disk before the system startup. Operate to use the disk. However, if the disk unit fails during the single operation of the secondary fusion disk, it is important to maintain the latest data, so the operation of the dual disk in the single operation with the disk device is started. The operation is repeated until it becomes possible.

[0007] A disk device used for a duplicated disk, if used as a duplicated disk, retains data up to the last time used as a duplicated disk, even if it is no longer used as a duplicated disk.

[0008]

However, in the above-mentioned conventional disk duplication system, when a duplicated disk composed of two disk devices is operated in a single operation and the operating disk device becomes an obstacle, the disk becomes unusable. There is a problem in that the single operation in the apparatus is continuously restored, and the operation of the duplicate disk cannot be started. This is because the maintenance of the latest data is regarded as important, so that the operation of the duplicated disk is controlled in order to maintain the operation state of the disk device that has been operated in a single operation with the latest data.

Further, in the conventional disk duplication system, since the only means for setting the use of the substitute disk device is the operation of the maintenance person, the disk operating during the unified operation of the duplicate disk during the unattended operation is operated. When the device fails, there is a problem that the disk device is continuously used and the duplicated disk cannot be used.

Further, in the conventional disk duplication system, an unused redundant disk device may hold data up to the last time used as a duplicated disk. If a disk unit fails, the operation of the duplicated disk will not be restored, but it will not be possible to switch over to the operation of an unused redundant disk unit and restore the operation of the duplicated disk unless an operation is performed by maintenance personnel. is there.

Furthermore, in the conventional disk duplication system, there is no means for reading the time information and indicating how long the disk device has been used in the duplicated disk. There is also a problem that it is difficult to know how long has been effective.

The present invention has been made in view of the above points,
It is an object of the present invention to provide a disk duplication system capable of restoring the duplication disk single operation even if a failure occurs in the disk device during the duplication disk single operation.

Another object of the present invention is to provide a disk duplication system which can easily determine how long the restored data of the duplicated disk has been valid.

Still another object of the present invention is to provide a disk duplication system that can easily determine that a disk device that has never been used as a duplicated disk has been used as a duplicated disk.

[0015]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention performs a duplex operation of a duplex disk comprising a first disk device and a second disk device, and performs a first disk device and a second disk device. In a disk duplexing system in which the same information is simultaneously written and read out to and from each of the disk devices, during a single operation in which only one of the first disk device and the second disk device is operated or when a single operation is started, a single operation target When it is detected that the single operation cannot be performed due to the failure of the disk device, the recovery operation for starting the disk device targeted for the single operation is performed. And a single operation is performed by selecting the other unused disk device.

According to the present invention, when it is detected that the single-drive operation cannot be performed due to the failure of the disk drive of the single-drive operation during the single-drive operation, a recovery operation for starting the single-drive operation disk device is performed, and the recovery operation is performed. If the recovery is not performed even after repeating the predetermined number of times, the other unused disk device that is not the target of the single operation is selected, so that the single operation using the other unused disk device can be performed.

Further, according to the present invention, the first disk device and the second disk device are periodically updated during the duplex operation, and a valid value is set when the duplex operation is performed. When not used, time information including a valid flag to which an invalid value is set is stored, and the time information is read from the disk device in the single operation during the single operation and displayed.

According to the present invention, it is possible to display the time information of the disk device that is operating during the single operation, and also to display whether the disk device has never been used in the redundant operation.

Further, in order to achieve the above object, the present invention controls a first disk device and a second disk device constituting a duplicated disk, and controls operations of the first disk device and the second disk device. Disk operating means for reading and writing, a disk operating state storage unit for storing operating states of the first disk device and the second disk device, and a disk operating unit read from the disk operating state storing unit. During the single operation in which the operation of the duplex operation means is controlled to cause the first disk device and the second disk device to perform the duplex operation or the single operation, and to operate only one of the first disk device and the second disk device. Or, when it is detected at the start of the unification operation that the unification operation cannot be performed due to the failure of the disk device targeted for the unification operation, the unification operation is performed. If the recovery operation for starting up the disk device is performed and the recovery operation is not repeated after the predetermined number of times, the unused disk device that is not the target of the single operation is selected by the disk redundant operation means to perform the single operation. And means for controlling the duplication of disks.

According to the present invention, when the disk duplication control means detects that the single-unit operation cannot be performed due to the failure of the single-unit operation disk unit during the single-unit operation, the recovery operation for activating the single-unit operation target disk unit. When the recovery operation is not repeated even after repeating the recovery operation a predetermined number of times, the disk redundant operation means is used to select the other unused disk device which is not the target of the single operation, so that the other unused disk device is used. Can be used for single operation.

Further, according to the present invention, the time periodically updated during the duplexing operation and the effective value when the duplexing operation is performed are set for the first disk device and the second disk device, and the duplexing is performed once. A disk time updating means for storing time information comprising a valid flag which is set to an invalid value when not used for operation, an input / output unit having a function of displaying information, and a single operation in a single operation A disk time display means for reading time information from the disk device inside and displaying the time information on the input / output unit is further provided.

In the present invention, the disk time display means can display the time information of the operating disk device during the single operation by the input / output unit, and the disk device has never been used for the duplex operation. Can also be displayed.

Further, the present invention is characterized in that a plurality of duplicated disks are provided, and the disk duplicate control means controls the operation of the plural duplicated disks independently of each other via the disk duplicate operation means. Here, one divided by two partitions of the first disk device and one divided by two partitions of the second disk device constitute a first duplicated disk, and The other divided by the two partitions and the other divided by the two partitions of the second disk device may constitute a second duplicated disk.

[0024]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a system configuration diagram of a first embodiment of a disk duplication system according to the present invention. As shown in FIG. 1, the disk duplication system includes a computer 10 operating under program control.
Disk operation state storage unit 20, input / output unit 30,
It comprises a disk duplication operation means 40, a first duplicated disk 50 composed of disk devices 51 and 52, and a second duplicated disk 60 composed of disk devices 61 and 62. Also, the disk devices 51, 52,
Time information 71, 72, 73 and 74 are stored in 61 and 62.

Further, the computer 10 includes a disk duplication control unit 11, a disk time display unit 12, and a disk time update unit 13. The disk duplication control means 11 uses the disk duplication operation means 40,
Controlling the duplication operation of a first duplicated disk 50 composed of disk devices 51 and 52 and a second duplicated disk 60 composed of disk devices 61 and 62;
If a change occurs in the duplex operation state, the disk operation state storage unit 20 is updated with the changed state. When the system is started, the disk operation state is read from the disk operation state storage unit 20, and the duplicate operation of the first duplicated disk 50 and the second duplicated disk 60 is started.

The disk duplication control means 11 normally controls the two disk devices 51 and 52 and the disk devices 61 and 62 constituting the duplicated disks 50 and 60 independently of each other between different duplicated disks. In the same duplexed disk, the same information is simultaneously written to and read from two disk units, and a duplicate operation is performed. However, one of the two disk units is replaced for maintenance because of the other. There is also a single operation operation in which only the disk device is operated.

The disk duplication control means 11 operates when a single disk drive, which is referred to as the above-mentioned single operation, fails when a single disk drive fails.
First duplicated disk 50 and second duplicated disk 6
In the case of "0", the operation state of the duplicated disk in which the disk device in the single operation has failed has been recovered.

However, if the disk device of the single operation among the first and second duplicated disks 50 and 60 cannot recover the operation state of the failed duplicate disk even after being repeated several times, The control means 11 automatically switches to the operation of the other disk device (unused redundant disk device) which has not been used in the single operation, and performs an emergency operation for restoring the operation. In addition, even when the system is started, if a disk failure occurs in the single operation, the disk duplication control unit 11 performs this operation state restoring operation.

After the operation of the first duplexed disk 50 and the second duplicated disk 60 is started by the emergency operation of the operation state restoring operation by the disk duplexing control means 11, the disk time display means 12 performs the first duplexing. The time information 71, 72, 7 is used so that the data last valid time of the disk 50 and the second duplicated disk 60 can be easily determined.
3 and 74 are output to the input / output unit 30 for display.

The disk time updating means 13 generates time information 71, 72, 73 of the disk device used for the first duplex disk 50 and the second duplex disk 60 among the disk devices 51, 52, 61 and 62. And 74 only.

The disk duplication operation means 40 reads and writes data from and to the first and second duplicated disks 50 and 60 in accordance with the duplication operation state controlled by the disk duplication control means 11. The first duplicated disk 50 and the second duplicated disk 60
Disk devices 51, 52, 61 and 62 constituting
Read / write from / to. In addition, it performs the duplication processing and the duplication release processing of the first duplicated disk 50 and the second duplicated disk 60.

As shown in FIG. 2, the disk operation status storage unit 20 stores information as to whether the disk devices 51 and 52 are being used for operating the first duplex disk 50, and whether the disk devices 61 and 62 are in the second configuration. The operating state of whether or not the disk is used for operation of the duplicated disk 60 is stored.

Next, the operation of this embodiment will be described with reference to FIGS. 1 to 3 and the flowcharts of FIGS. The disk duplication control means 11 performs a normal operation as follows. The disk duplication control means 11 uses the disk duplication operation means 40 to
A first duplicated disk 50 composed of
By controlling the second disk 60 composed of the disk devices 61 and 62 and changing the duplex operation state,
The disk operation state storage unit 20 is updated with the changed state. When the system is started, the disk status is read from the disk status storage unit 20, and the duplex operation of the first and second duplex disks 50 and 60 is started.

When a failure occurs in the disk device during the single operation, the disk duplication control means 11 performs the following operation state restoring operation. That is, the disk duplication control means 11 operates the first duplicated disk 50 and the second duplicated disk 60 so as to prevent the loss of the latest data for a while.
Among them, the operation state of the duplicated disk in which the disk device in the single operation has failed is restored.

However, if the operation state of the failed disk unit among the first duplicated disk 50 and the second duplicated disk 60 cannot be restored even after being repeated several times, the duplicated disk In order to prevent a long stoppage, the operation is automatically switched to the operation of the other disk device (unused redundant disk device) that has not been used in the single operation, and an emergency operation for restoring the operation is performed. Incidentally, even when the system is started, if a disk failure occurs in the single operation, the disk duplication control means 11
Performing this operation state restoring operation is as described above.

The above-mentioned emergency operation is performed when the disk device of the single operation of the first and second duplicate disks 50 and 60 cannot recover the operating state of the failed duplicate disk. In some cases, the duplex disks 50 and 60 are both operated in a single operation in parallel, or only one of the disks is operating in a single operation while the other is operating in a normal operation. Although the states are performed independently of each other, the following description will be made by taking as an example a case where the duplexed disks 50 and 60 are operating in parallel and in a single operation.

The operation state restoring operation will be described with reference to the flowchart of FIG. Disk duplication control means 11
Checks whether the following operation is repeated six times or more (step A1). If the number of repetitions is less than six, in order to prevent the latest data from being lost, the disk duplication operation means 40 is used to maintain the operation state of the first and second duplicated disks 50 and 60, and the duplicated disk 50,
A recovery operation is performed to operate the disk device that is operating as a single unit 60 (steps A2 and A3).

Next, it is determined whether or not the operation of the duplexed disks 50 and 60 (strictly, the operation of the disk device to be unified) is started (step A4). If the operation can be started, the operation is terminated. Cannot be started, the process returns to step A1 again, and it is checked whether the recovery control of the duplicated disk has been repeated six times or more. If the repetition is six times or more, the following emergency operation is performed to prevent the duplicated disks 50 and 60 from being stopped for a long time. That is, it is checked whether the repetition is an even number of times (step A5).
If the repetition is an even number of times, the disk device 51 is selectively used for the first duplexed disk 50, and the disk device 61 is selectively used for the second duplicated disk 60 (step A6).

On the other hand, when the repetition is an odd number of times, the disk device 52 is selectively used in the first duplicated disk 50, and the disk device 62 is selected in the second duplicated disk 60.
Is selected and used (step A7). Steps A6 and A
After the processing of step 7, the configuration of the duplexed disk is controlled (step A3). Subsequently, it is determined whether or not the operation of the duplexed disks 50 and 60 has been started (step A4). If the operation can be started, the operation is terminated. If the operation cannot be started, the flow returns to step A1 again, and it is checked whether or not the recovery control of the duplicated disk has been repeated six times or more.

First and second duplex disks 50 and 6
This operation is repeated until 0 becomes available (step A4). In this way, the first and second duplex disks 50 and 60 operate so that the duplex operation can be started.

When the system is started, the disk units 51, 5 are stored in the operating state storage unit 20 in a format as shown in FIG.
The operation states of 2, 61 and 62 are read, and the operation of the duplex disks 50 and 60 is maintained.

Next, the operation of displaying and outputting the time information 71 to 74 by the disk time display means 12 to the input / output unit 30 will be described with reference to the flowchart of FIG. Note that this display output operation is performed only when the disk duplication control unit 11 performs the emergency operation of the operation state recovery operation.

The disk time display means 12 first reads the time information 71 on the disk device 51 (step B).
1). If the disk device 51 is operating normally, the time information 71 can be read in the format of FIG. 3 (step B).
2) The validity flag is confirmed to be valid (step B3). If the valid flag is valid, the update time of the time information 71 shown in FIG. 3 is displayed and output to the input / output unit 30 (step B4).

On the other hand, when the time information 71 cannot be read in the format shown in FIG. 3 due to a failure of the disk device 51 (step B2), or when the time information 71 can be read but the valid flag is not valid (step B3), Time information 7
A time information invalidity indicating that 1 could not be read is displayed and output to the input / output unit 30 (step B5). Time information 72 on the other disk devices 52, 61 and 62,
The same operation as described above is performed on 73 and 74.

The above is the operation of the disk duplication control means 11 and the disk time display means 12 when the disk device fails during the single operation.

Next, the operation of the disk duplication control means 11 and the disk time update means 13 during normal system operation will be described. The disk duplication control means 11 uses the disk duplication operation means 40 to
A first duplicated disk 50 composed of
The duplex operation with the second duplex disk 60 composed of the disk devices 61 and 62 is controlled. When the duplex operation state is changed, the changed duplex operation state is recorded in the disk operation state storage unit 20 in the format of FIG.

The disk time updating means 13 outputs the time information 71, only to the disk device used for the duplex operation among the disk devices 51, 52, 61 and 62.
72, 73 and 74 are updated periodically. The update is shown in FIG.
As shown in (1), the update time and the validity flag are set in association with each other.

Next, the operation of this embodiment will be described more specifically. As shown in FIG. 2, the disk status storage unit 20 stores the first duplex disk 50 as a single operation in the disk device 51 and the second duplex disk 60 as a single operation in the disk device 62. Further, a specific description will be given of the time of system startup when a failure occurs in the disk device 51.

When the system is started, the disk duplication control means 11 reads from the disk state storage unit 20 that the first duplicated disk 50 is a single operation by the disk device 51,
The second duplicated disk 60 reads information indicating that the operation is the single operation in the disk device 62. Accordingly, the disk duplication control unit 11 attempts to start the single duplication operation of the duplicated disks 50 and 60 according to the read information. Since the duplication operation is not started, the operation state restoring operation is performed on the duplicated disk 50.

That is, as described above with reference to FIG. 4, the disk duplication control unit 11 checks whether the operation for restoration is repeated six times or more (step A1).
However, since the system has not been repeated at the time of system startup, the first duplicated disk 50 restores the single operation of the disk device 51 to prevent the latest data from being lost (steps A1, A2, and A3). However, since the disk device 51 fails and cannot be used, the duplication operation of the first duplicated disk 50 is not started, so that this operation is repeated (steps A4, A1 to A3).

In some cases, the failure of the disk device 51 may be temporary.
The unification operation of the first duplex disk 50 can be started, and this operation may be terminated based on the determination in step A4. However, when this repetition operation is repeated six times, the disk duplication control unit 11 performs an emergency operation without using the disk operation state storage unit 20.

That is, in the case of the sixth repetition, the number of repetitions is an even number, so the first duplicated disk 5
At the time of recovery from 0, the disk device 51 is selectively used (steps A5 and A6). However, since the disk device 51 fails and cannot be used, the single operation of the first duplicated disk 50 is not started, so this operation is repeated (steps A3, A4, A1). In step A6, the second
When the dual disk 60 is restored, the disk device 61 is selectively used.

Subsequently, since the number of repetitions is determined to be seven in step A2, the number of repetitions is an odd number, so that when the first duplexed disk 50 is restored, the disk device 52 is restored.
Is selected and used (step A7), and the single operation is restored (step A4). Since the disk device 52 is not a failure, the single operation of the first duplicated disk 50 can be started. When the start of the single operation is confirmed (step A4), the emergency operation is ended. In step A7, the disk device 62 is selectively used when the second duplicated disk 60 is restored.

At this time, as shown in FIG. 2, the disk device 62 is being used by the second disk 60, and the data held is the latest. On the other hand, the disk device 52
Is not used in the dual disk 50 and the data held is not the latest. However, although the data is old, the unification operation of the first duplicated disk 50 can be started (the unified operation is normally started in the second duplicated disk 60).

Subsequently, the disk time display means 12 performs the following operation. The operation of the disc time display means 12 will be described by taking as an example a case where the time information 71 to 74 are set as shown in FIG.

The disk time display means 12 displays the time information 7
1 is read, but the time information 71 cannot be read because the disk device 51 is faulty, and the fact that the time information could not be read from the disk device 51 is displayed and output to the input / output unit 30 ( Step B1 of FIG.
B2, B5). Next, the disk time display means 12 reads the time information 72 of the next disk device 52 (step B1 in FIG. 5). Since the disk device 52 is normal,
Reading is possible (step B2 in FIG. 5), and it is checked whether or not the valid flag is valid (step B3 in FIG. 5). However, as shown in FIG. 3, the valid flag is valid. “789” is output to the input / output unit 30 as time information of the disk device 52 (step B in FIG. 5).
4) Display.

Thereafter, in the same manner as described above, the next disk device 6
The time information 73 and 74 of the first and the second 62 are sequentially read (FIG.
Step B1), since these disk devices 61 and 62 are normal, reading is possible (step B1 in FIG. 5).
2) Subsequently, it is checked whether or not the valid flag is valid (step B3 in FIG. 5). Since the valid flag is valid as shown in FIG.
“1000” is output to the input / output unit 30 as time information of the disk devices 61 and 62 (step B4 in FIG. 5) and displayed.

Thus, the screen of the input / output unit 30 displays the disk device and the last data valid time in association with each other as shown in FIG. As you can see from this display,
The last data valid time of the disk devices 52, 61, and 62 is known, and it is easy to compare with the current time to determine to what point in time the data of the disk device 52 used for the first duplex disk 50 is valid. can do.

Since the validity flag of a disk device that has never been used as a duplicated disk is invalid, the duplicated disk is never used by the emergency operation of the operation state recovery operation based on the displayed validity flag. If a disk device that has not been used is used as a duplicated disk, it can be easily determined.

As described above, according to this embodiment, 6
If the recovery operation is not repeated even more than once, the disk device used in the unified operation is automatically switched to the redundant disk device side, so the system starts during unattended operation and the unified operation is performed Even if a failure occurs in the disk device, a single operation can be started by preventing stoppage for a long time.

Next, a second embodiment of the present invention will be described. FIG. 7 shows a system configuration diagram of a second embodiment of a disk duplex system according to the present invention. In the figure,
The same components as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. As shown in FIG. 7, in this embodiment, the disk device 61 is divided by two partitions of areas 61a and 61b, and similarly, the disk device 62 is also divided by two partitions of areas 62a and 62b. . The areas 61a and 62a constitute a second duplicated disk 60, and the areas 61b and 62b constitute a third duplicated disk 80.

Further, the regions 61a, 62a, 61b and 6
2b stores time information 73, 74, 75 and 76, respectively. These time information 73, 74, 75, and 76 are updated periodically by the disk time updating unit 14 when partitions are used for the second duplex disk 60 and the third duplex disk 80.

The disk time display means 15 displays the time information 71 only when the disk duplication control means 11 performs the emergency operation of the operation state recovery operation and the system startup is completed.
72, 73, 74, 75, and 76 are displayed and output to the input / output unit 30. Thus, even if the disk device is divided into partitions and a duplicated disk is configured for each partition, the disk duplication control means 11
Performs emergency operation and completes system startup, and can output and output the time information 71, 72, 73, 74, 75 and 76 to the input / output unit 30.

In this embodiment, if the disk duplication control means 11 does not recover after repeating the operation for recovery six times or more, a failure occurs during the single operation in order to prevent the redundant disk from being stopped for a long time. Change the operating state of a duplex disk having a disk device. In the case where all the duplexed disks 50, 60 and 80 operate in a single operation, a failure occurs in a disk device operating in a single operation with a certain duplicated disk, and the number of repetitive operations for recovering the failure is 6 or more and an even number of times. In case, dual disk 5
The disk devices 51, 61a and 62a are selected as the disk devices for the single operation of 0, 60 and 80, respectively.

Thus, when the single operation is not restored, the restoring operation is performed again. As a result, the number of repetitive operations for restoration becomes six or more and an odd number. In this case,
The disk devices 52, 61b and 62b are selected as the disk devices for the single operation of the duplex disks 50, 60 and 80, respectively. In this way, an unused redundant disk device of a duplicated disk having a failed disk device during the single operation is selected, and the operating state of the duplicated disk having no failure is restored, and the first and second redundant disks are restored. The duplication operation of the second duplication disks 50 and 60 can be started.

The present invention is not limited to the above embodiment, and various other modifications are conceivable. For example, in FIGS. 1 and 7, there are a plurality of duplicated disks, but it is needless to say that only a single disk may be used. In a system having a plurality of duplicated disks, the operation states of the respective duplicated systems are independent of each other. The emergency operation may be performed only for the redundant system to be operated.

That is, in FIG. 4, it is assumed that both redundant systems are operating in a single operation, and the switching of the disk device is also selected in the normal redundant operation. Alternatively, the switching to the redundant disk device may be selected only for the redundant system in which the disk device has failed. Also, when the other duplex disk is performing the duplex operation, it is needless to say that the above-mentioned disk device switching selection is not performed for the other duplex disk.

[0068]

As described above, according to the present invention,
When detecting that the unification operation cannot be performed due to the failure of the unification operation target disk device during the unification operation, a recovery operation for starting the unification operation target disk device is performed,
If the recovery operation is not repeated after the predetermined number of times, the unified operation is performed using the other unused disk device by selecting the other unused disk device that is not targeted for the unified operation. Therefore, even if the system is started during unattended operation and a failure occurs in the disk device in the single operation, the single operation can be restored, and the duplicated disk can be prevented from being stopped for a long time.

Further, according to the present invention, the time information of the operating disk device can be displayed at the time of the single operation, so that when the emergency operation of the single operation recovery operation is performed, the data of the dual disk can be displayed. The last valid time can be easily determined.

Further, according to the present invention, the displayed time information also includes an effective flag indicating whether or not the disk device in the duplicated disk in which the single operation has been restored has never been used in the duplicate operation. Therefore, when a desk device that has never been used as a duplicated disk is used as a duplicated disk, it can be easily determined.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of a first embodiment of a system of the present invention.

FIG. 2 is an explanatory diagram of contents stored in a disk operation state storage unit in FIG. 1;

FIG. 3 is an explanatory diagram of an example of time information.

FIG. 4 is a flowchart for explaining an operation state restoring operation by the disk duplication control means in FIG. 1;

FIG. 5 is a flowchart for explaining an operation of displaying and outputting time information to an input / output unit by a disk time display unit in FIG. 1;

FIG. 6 is a diagram showing an example of time display by the input / output unit in FIG. 1;

FIG. 7 is a system configuration diagram of a second embodiment of the system of the present invention.

FIG. 8 is a flowchart for explaining an operation of an example of a conventional system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Computer 11 Disk duplication control means 12, 15 Disk time display means 13, 14 Disk time update means 20 Disk operation state storage unit 30 Input / output unit 40 Disk duplication operation means 50 First duplicated disk 51, 52, 61, 62 disks Apparatus 60 Second duplicated disk 61a, 61b, 62a, 62b Area (partition) 71-76 Time information 80 Third duplicated disk

Claims (7)

[Claims] 1. A disk for performing a duplex operation of a duplicate disk comprising a first disk device and a second disk device, and simultaneously writing and reading the same information to and from the first disk device and the second disk device, respectively. In the duplex system, during the single operation in which only one of the first disk device and the second disk device is operated, or at the time of starting the single operation, the single operation cannot be performed due to the failure of the disk device targeted for the single operation. When it is detected, a recovery operation for activating the disk device to be subjected to the unification operation is performed, and when the recovery operation is not performed even after repeating the recovery operation a predetermined number of times, the other unused disk which is not the target of the unification operation is operated. A disk duplication system characterized by selecting a device and performing a single operation. 2. The time when the first disk device and the second disk device are periodically updated during the duplex operation and the effective value when the duplex operation is performed are set, and the first disk device and the second disk device have been used for the redundant operation once. When there is no time information, time information including a valid flag to which an invalid value is set is stored, and the time information is read out from the disk device in the single operation during the single operation and displayed. 2. The disk duplication system according to 1. 3. A first disk device and a second disk device constituting a duplex disk, and a disk duplex operation for reading and writing by controlling operation of the first disk device and the second disk device. Means, a disk operation state storage unit that stores operation states of the first disk device and the second disk device, and an operation of the disk duplex operation unit that is controlled according to an operation state read from the disk operation state storage unit. Operating the first disk device and the second disk device in a duplex operation or a single operation, and operating only one of the first disk device and the second disk device during the single operation or starting the single operation. Sometimes, when it is detected that the single operation cannot be performed due to the occurrence of a failure in the disk device targeted for the single operation, the disk for the single operation is detected. When the recovery operation for starting the disk device is performed and the recovery operation is not repeated even if the recovery operation is repeated a predetermined number of times, the other disk device not used as the single operation target is selected by the disk redundant operation means. A disk duplication control means for performing a single operation. 4. A time that is periodically updated during the duplex operation and a valid value when the duplex operation is performed are set for the first disk device and the second disk device, and are used for the redundant operation once. A disk time update unit for storing time information including a valid flag to which an invalid value is set when not performed; an input / output unit having a function of displaying information; and 4. The disk duplex system according to claim 3, further comprising disk time display means for reading the time information from a disk device and displaying the time information on the input / output unit. 5. The disk duplication control means, when the recovery operation is not repeated after repeating the recovery operation a predetermined number of times, when the next recovery operation is repeated an odd number of times,
4. The disk duplication operation means is selected by the disk duplication operation means, and when the number of repetitions of the next recovery operation is an even number, the second disk apparatus is selected by the disk duplication operation means. Or 4
The described disk duplication system. 6. The disk duplication control means is provided with a plurality of duplicated disks, and the disk duplication control means controls the operation of the plurality of duplicated disks independently of each other via the disk duplication operation means. Or the disk duplication system according to 4. 7. One of the first disk devices divided by two partitions and one of the second disk devices divided by two partitions constitute a first duplicated disk, and 7. The second duplicated disk according to claim 6, wherein the other divided by two partitions of one disk device and the other divided by two partitions of the second disk device constitute a second duplicated disk. Redundant system.