JP2003345523A - Method for controlling data multiplexing system, data multiplexing system, sub-storage device and program for sub-storage device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data multiplexing system equipped with a plurality of master storage devices and sub-storage devices for improving the processing capability of the whole system. <P>SOLUTION: This data multiplexing system consists of the plurality of master storage devices connected to a host computer and sub-storage devices to which those master storage devices are connected to hold data in multiplexed conditions. When it is detected that the condition of sub-data arrival from a certain master storage device reaches a certain set condition, the sub-storage device either instructs the master storage device to stop the transfer of the sub-data, or processes the sub-data not time-sequentially on the basis of the time stamp but writes the sub-data in a storage volume in the order of arrival, or prevents the host computer from transmitting the data to the master storage device. <P>COPYRIGHT: (C)2004,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a control method for a data multiplexing system, a data multiplexing system, a secondary storage device, and a program for a secondary storage device.

[0002]

2. Description of the Related Art With the recent development of the IT industry and the Internet technology, the amount of data handled by companies and the like is rapidly increasing. In order to store and manage such a large amount of data,
A large-capacity external storage device such as a disk array device provided with a large number of physical devices (for example, magnetic disks) is used.

In order to prevent data loss or damage of the external storage device due to the occurrence of a disaster or the like, a data backup storage device (“secondary storage device” in this specification) is provided at a location away from the external storage device. A data multiplexing system that multiplexes data in both the external storage device (referred to as “primary storage device” in this specification) and the secondary storage device is known. I have. Further, in order to reduce the scale and resources of the backup secondary storage device, a plurality of primary storage devices are connected to one secondary storage device, and the configuration ratio of the primary storage device: secondary storage device is N. 1: 1 data multiplexing systems are also known.

[0004]

In the above-described data multiplexing system in which the composition ratio of the primary storage device to the secondary storage device is N: 1, for example, each primary storage device and secondary storage device are connected to each other. Due to the difference in data transfer capability between the storage devices, or the size of the data transferred at one time, the arrival status of data from each primary storage device to the secondary storage device may be biased. When such an imbalance occurs, only data from a specific primary storage device accumulates in the secondary storage device, which may hinder the processing of the secondary storage device and the entire system.

Accordingly, an object of the present invention is to improve the processing capability of the entire system in a data multiplexing system including a plurality of primary storage devices and secondary storage devices.

[0006]

According to one aspect of the storage system control method of the present invention, a plurality of primary storage devices having at least one primary storage volume and at least one secondary storage volume are provided. A secondary storage device connected to a plurality of primary storage devices, and secondary data having the same contents as primary data stored in a primary storage volume of each primary storage device are transferred to the secondary storage device. And storing the data in the secondary storage volume of the secondary storage device so that the primary storage device and the secondary storage device hold data in a multiplex manner. This control method includes a step A in which the secondary storage device manages the arrival status of the secondary data, and a host computer in which the secondary storage device is connected to the plurality of primary storage devices. Based on the time information attached to the primary data and the secondary data to indicate the time at which the primary data was transmitted to the storage device, the received secondary data is stored in the secondary storage volume in chronological order. In the writing step B, when the arrival status of the secondary data from a certain primary storage device satisfies a set condition, the arrival status of the secondary data from the certain primary storage device is set to the setting. And a step C of performing a condition departure process for deviating from the set condition.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS == Summary of Disclosure == A first aspect of a control method for a data multiplexing system according to the present invention includes a plurality of primary storage devices provided with at least one primary storage volume, and at least one primary storage device. A secondary storage device having a secondary storage volume and a secondary storage device connected to the plurality of primary storage devices, the secondary data having the same contents as the primary data stored in the primary storage volume of each of the primary storage devices. To the secondary storage device and store the data in the secondary storage volume of the secondary storage device, thereby multiplexing data in the primary storage device and the secondary storage device for multiplexing data. A control method in a system, wherein the secondary storage device manages the arrival status of the secondary data in a step A, and the secondary storage device connects to the plurality of primary storage devices. Based on the time information attached to the primary data and the secondary data to represent the time at which the computer transmitted the primary data to each primary storage device, the received secondary data was chronologically ordered. Step B of writing to the secondary storage volume, and when the arrival status of the secondary data from a certain primary storage device satisfies a set condition, the secondary data from the certain primary storage device is A step C of executing a condition departure process for causing the arrival status to deviate from the set condition.

Here, the “storage volume” is a physical drive (disk device) mounted on the primary storage device and the secondary storage device, a group of physical drives including a plurality of physical drives, and a storage area provided by the physical device. Storage of data such as a logical device which is a storage area logically organized on a logical device group and a logical device group including a plurality of logical devices.
It is a unit of management. The “arrival status” refers to a status such as the number of secondary data arriving at the secondary storage device, the amount of secondary data, the number or amount ratio of secondary data from each primary storage device, and the like. “Condition withdrawal processing” is synonymous with what is referred to as “temporary processing” described in detail later in this specification.

With such a configuration, in a data multiplexing system having a plurality of primary storage devices and secondary storage devices, if the arrival status of secondary data satisfies a set condition (eg, each primary storage device) When the arrival status of the secondary data from the storage device becomes unbalanced), the above-mentioned condition departure processing (or extraordinary processing) is executed to eliminate the unbalanced state and to improve the overall system. Processing capacity can be improved.

In a second aspect of the control method of the data multiplexing system according to the present invention, the secondary data to be written to the secondary storage volume received from all of the plurality of primary storage devices is the secondary data. When the data is accumulated in the secondary storage device, the secondary storage device executes the step B, and when the secondary storage device executes the process B, the secondary storage device writes the data to the secondary storage volume last. The time information of the secondary data is obtained.

With such a configuration, in the entire data multiplexing system (that is, over a plurality of primary storage devices), the secondary storage device can write the secondary data at any time to the secondary storage volume. It is possible to consistently grasp and guarantee whether or not the processing has been completed, thereby improving the usefulness of the entire system and meeting the needs of the user.

In a third aspect of the control method of the data multiplexing system according to the present invention, in the condition leaving process in the step C, the secondary storage device stops the process B and the primary storage devices This is a process of writing the secondary data to the secondary storage volume in the order in which the data has been transferred from the secondary storage volume.

With this configuration, the transfer of the secondary data to any primary storage device is not stopped.
The unbalanced state of the arrival status of the secondary data from each primary storage device can be eliminated.

In a fourth aspect of the control method of the data multiplexing system according to the present invention, the condition departure processing in the step C is such that the secondary storage device transmits the secondary data to the certain primary storage device. This is a process in which a command instructing to stop the transfer of the data is transmitted, and the certain primary storage device that has received the command grasps data that has not been transferred to the secondary storage device.

With such a configuration, in the data multiplexing system as a whole, it is possible to consistently grasp and guarantee up to which time the secondary data has been written to the secondary storage volume, and to guarantee the secondary data from a plurality of primary storage devices. The unbalanced state of the arrival status of the secondary data can be eliminated.

In a fifth aspect of the control method of the data multiplexing system according to the present invention, in the condition departure processing in the step C, the secondary storage device sends the primary storage device to the certain primary storage device by the host computer. This is a process of transmitting to the certain primary storage device an instruction that causes the transmission of the side data to be stopped.

With such a configuration, in the entire data multiplexing system, each primary storage device 2-2 is consistently grasped and assured at what time secondary data has been written to the secondary storage volume, and assured. The unbalanced state of arrival of the secondary data from 0, 2-1 and 2-2 can be eliminated.

In a sixth aspect of the control method of the data multiplexing system according to the present invention, as the condition departure process of the step C, the secondary storage device suspends the process B and executes the respective primary storage devices. A process of writing the secondary data to the secondary storage volume in the order in which the secondary data has been transferred, and the secondary storage device instructs the certain primary storage device to stop the transfer of the secondary data. The primary storage device that has received the instruction to perform the process of ascertaining data that has not been transferred to the secondary storage device, and that the secondary storage device has the host computer And a process of transmitting to the certain primary storage device an instruction which triggers the transmission of the primary data to the primary storage device to be stopped. Side storage device And, wherein the step C is performed in accordance with the designation information.

With such a configuration, a user using the data multiplexing system can freely designate temporary processing according to needs.

In a seventh aspect of the control method of the data multiplexing system according to the present invention, as the condition departure process of the step C, the secondary storage device suspends the process B and executes the respective primary storage devices. A process of writing the secondary data to the secondary storage volume in the order in which the secondary data has been transferred, and the secondary storage device instructs the certain primary storage device to stop the transfer of the secondary data. The primary storage device that has received the instruction to perform the process of ascertaining data that has not been transferred to the secondary storage device, and that the secondary storage device has the host computer The secondary storage device selects and executes one of a process for transmitting to the certain primary storage device an instruction which triggers the transmission of the primary data to the primary storage device to be stopped. I do.

With such a configuration, the secondary storage device
Temporary processing can be selected and executed flexibly in order to eliminate the unbalanced state of the arrival status of the secondary data from each primary storage device.

In an eighth aspect of the data multiplexing system control method according to the present invention, when the step C is performed,
An external notifying means selected by the secondary storage device from the group consisting of the primary storage device, the host computer, a computer connected to the secondary storage device, and an alarm device provided in the secondary storage device Step E to notify
Is provided.

With such a configuration, it is possible to notify the user or the system administrator of the shift to the condition departure processing (or the temporary processing).

In the ninth aspect of the control method of the data multiplexing system according to the present invention, the "set condition of the arrival status of the secondary data from a certain primary storage device" is the one of the primary data. The amount of secondary data from the storage device exceeds the set value, the ratio of the amount of secondary data from each primary storage device exceeds the set ratio, and the amount of secondary data from each primary storage device. It is selected from the group consisting of the remaining capacity of the storage medium storing the side data being less than the set value.

According to another aspect of the data multiplexing system of the present invention, a plurality of primary storage devices provided with at least one primary storage volume, and a plurality of primary storage devices provided with at least one secondary storage volume are provided. A secondary storage device connected to the device, and transferring secondary data having the same content as primary data stored in the primary storage volume of each primary storage device to the secondary storage device, A data multiplexing system for storing data in the primary storage device and the secondary storage device in a multiplex manner by storing the data in the secondary storage volume of the storage device. Here, the secondary storage device has a means for managing the arrival status of the secondary data, and a host computer connected to the plurality of primary storage devices has transmitted the primary data to each of the primary storage devices. Means for writing the received secondary data to the secondary storage volume in chronological order based on time information added to the primary data and the secondary data to represent time, and the primary storage A condition that, when the arrival status of the secondary data from the device satisfies a set condition, the arrival status of the secondary data from the certain primary storage device deviates from the set condition; Means for performing a withdrawal process.

One aspect of the secondary storage device in the data multiplexing system of the present invention comprises a plurality of primary storage devices having at least one primary storage volume, and at least one secondary storage volume. A secondary storage device connected to a plurality of primary storage devices, and secondary data having the same contents as primary data stored in a primary storage volume of each primary storage device are transferred to the secondary storage device. Then, by storing the data in the secondary storage volume of the secondary storage device, the secondary storage device in the data multiplexing system for holding data in the primary storage device and the secondary storage device in a multiplexed manner. is there. The secondary storage device includes means for managing the arrival status of the secondary data,
Based on the time information attached to the primary data and the secondary data to represent the time at which the host computer connected to the plurality of primary storage devices transmitted the primary data to each primary storage device. Means for writing the received secondary data to the secondary storage volume in chronological order,
When the arrival status of the secondary data from a certain primary storage device satisfies a set condition, the arrival status of the secondary data from the certain primary storage device deviates from the set condition. Means for performing a condition departure process for performing such a process.

One aspect of the program for the secondary storage device in the data multiplexing system of the present invention is a process A for managing the arrival status of the secondary data in the secondary storage device.
And time information attached to the primary data and the secondary data to represent the time at which the host computer connected to the plurality of primary storage devices transmitted the primary data to each primary storage device. Writing the received secondary data to the secondary storage volume in chronological order, and when the arrival status of the secondary data from a certain primary storage device satisfies a set condition, A program for executing a step C of executing a condition departure process for making the arrival status of the secondary data from a certain primary storage device deviate from the set condition.

== Configuration of Data Multiplexing System == FIG. 1 is a schematic configuration diagram showing an embodiment of a data multiplexing system according to the present invention. In the illustrated example, the host computer 1 and three primary storage devices 2-0 and 2-
1 and 2-2 are connected via the network 4.
This network 4 is a SAN using Fiber Channel.
, A LAN, or any other network. On the other hand, the three primary storage devices 2-0, 2-1 and 2-2 are connected to one secondary storage device 3 via the interface cable 5. When the primary storage devices 2-0, 2-1 and 2-2 and the secondary storage device 3 are remotely located, the interface cable 5
Any information communication medium such as an optical fiber, a communication line, and a wireless communication network may be used.

The primary storage devices 2-0, 2-1 and 2-2 are:
Each includes a storage controller 20 and one or more primary storage volumes 21. Each primary storage device 2-0, 2-
The storage controllers 1 and 2 are channel adapters 22 (CHA in the figure) that control each port (not shown) for establishing a connection with the host computer and the secondary storage device 3.
), A disk adapter 23 (described as DKA in the figure) for controlling the primary storage volume 21, a cache memory 24, and a shared memory 25.

The secondary storage device 3 includes primary storage devices 2-0,
This is a storage device for backup, for example, provided to hold the data held by 2-1 and 2-2 also on the secondary storage device 3 side. The secondary storage device 3 includes a storage control device 30 and one or more secondary storage volumes 31. In this example, three primary storage devices 2-0, 2-1 and 2
-2 three secondary storage volumes 3 corresponding to
1 (that is, the storage volumes 31 and 2-1 for the storage volumes 31 and 2-1) are provided, but the present invention is not limited to such a configuration.
The storage control device 30 includes the primary storage devices 2-0, 2-1,
2-2, a channel adapter 32 (described as CHA in the figure), a disk adapter 33 controlling each storage volume (described as DKA in the figure), a cache memory 34, and a shared memory 35. including.

The storage controller 31 of the secondary storage device 3
Are three queues 200 for storing and managing data transferred from the primary storage devices 2-0, 2-1 and 2-2 for each of the primary storage devices 2-0, 2-1 and 2-2. , 210,22
0 (described below with reference to FIG. 2). These queues 200, 210, and 220 may be provided in the cache memory 34 as in the present embodiment, or may be provided in another appropriate storage medium.

In FIG. 1, the primary storage devices 2-0, 2
-1, 2-2 and the secondary storage device 3 are the storage control device 2
It has been described that the storage volumes 0 and 30 and the storage volumes 21 and 31 are provided in the same housing. However, the configurations of the primary storage devices 2-0, 2-1 and 2-2 and the secondary storage device 3 are not limited to those described above.
30 and the storage volumes 21 and 31 may be provided separately and independently.

The host computer 1 may be any computer such as a mainframe, an open server such as UNIX (registered trademark), or a PC server.

== Overview of Asynchronous Remote Copy == Primary Storage Units 2-0, 2-1 and 2-2 and Secondary Storage Unit 3
, That is, writing data to the primary storage volume 21 of the primary storage devices 2-0, 2-1 and 2-2 at a timing asynchronous with the secondary storage device 3 A technique for writing the data to the secondary storage volume 31 will be described. Since the primary storage devices 2-0, 2-1 and 2-2 operate in the same manner, only the operation of the primary storage device 2-0 will be described here.

When receiving the write data from the host computer 1, the primary storage device 2-0 writes the received data into the primary storage volume 21. The write data received by the primary storage device 2-0 from the host computer 1 and written to the primary storage volume 21 includes time information (hereinafter referred to as a "time stamp") indicating the time at which the host computer 1 transmitted the data. Is attached.

The primary storage device 2-0 stores data having the same contents as the written data (hereinafter referred to as "secondary data").
Is created in the cache memory 24. The secondary data is provided with the same time stamp as the corresponding data written in the primary storage volume 21 (that is, information indicating the time at which the host computer 1 transmitted the data).

When the secondary data has been created in the cache memory 24, the primary storage device 2-0 transfers the secondary data to the secondary storage device 3.

The secondary storage device 3 stores the secondary data transferred from the primary storage device 2-0 in a queue 200 (see FIG. 2) for the primary storage device 2-0. Are written in chronological order from the rear side (left side in FIG. 2) of the queue 200 to the top side (right side in FIG. 2) in accordance with the time stamp attached to.

As described above, the secondary storage device 3 caches the three queues 200, 210, 220 (see FIG. 2) corresponding to the primary storage devices 2-0, 2-1 and 2-2. It is provided on the memory 34. Queues 200, 210, 2
20, each primary storage device 2-0, 2-1 and 2
When the secondary data from -2 is stored (the state of FIG. 2B), the secondary storage device 3 stores the queues 200, 210,
220 is checked from the top side, and based on the time stamp attached to each piece of secondary data, the secondary data is written to the corresponding secondary storage volume 31 in the order of the timestamp of the time stamp (first in this example). The secondary data with the time stamp “09:10” is processed).

A plurality of primary storage devices 2-0, 2-1 and 2-
2 is connected to one secondary storage device 3 in the present data multiplexing system,
It is necessary to consistently grasp and guarantee up to what time data has been backed up by the secondary storage device 3 (across the primary storage devices 2-0, 2-1 and 2-2). Therefore, the secondary storage device 3 sets the time stamp (09:10 in the above example) of the secondary data written in the secondary storage volume 31 to the backup guaranteed time of the entire data multiplexing system. (Consistency time) is stored in the cache memory 34 or another appropriate storage medium (not shown). This consistency time can be viewed on a management computer (not shown) connected to the secondary storage device 3, or transmitted from the secondary storage device 3 to the host computer 1 and transmitted to the host computer 1. It can also be viewed with a simple interface.

On the other hand, if all the queues 200, 210, and 220 do not store the secondary data from each of the primary storage devices 2-0, 2-1 and 2-2 (the state shown in FIG. 2A). ),
It is assumed that the secondary storage device 3 does not store secondary data in the secondary storage volume 31 and does not acquire a consistency time as a guaranteed backup time of the entire data multiplexing system.

== Transition of Secondary Storage to Temporary Processing == FIG. 3 shows an embodiment of a data multiplexing system according to the present invention, in which primary storages 2-0, 2-1 and 2-2 are FIG. 4 is a schematic diagram showing a state in which secondary data is transferred to and from a secondary storage device 3. For simplicity, FIG. 3 shows the cache memory 24 of each primary storage device 2-0, 2-1 and 2-2 and the queue 20 on the cache memory 34 of the secondary storage device 3.
0, 210, and 220 and only the interface cable 5 are shown.

For example, each primary storage device 2-0, 2-1 and 2
-2 and a difference in the data transfer capacity between the secondary storage device 3 and the size of the secondary data,
Variations may occur in the transfer order of the secondary data. Also, for some reason, a certain primary storage device 2-0 / 2-1 / 2
There is a possibility that a state in which the secondary data cannot be transferred between -2 and the secondary storage device 3 may occur.

In such a case, for example, as shown in FIG. 3, a certain primary storage device 2-0 / 2-1 / 2-2 is used.
Cache memory 2 of (primary storage device 2-1 in this example)
4, the secondary data that has an old time stamp and has not been transferred to the secondary storage device 3 (in this example, the time stamp is “09: 1
0 secondary data) may remain. Then, since the secondary data is not stored in the 2-1 queue 210 of the secondary storage device 3, the secondary storage device 3 checks each of the queues 200, 210, and 220 and checks the secondary queue having the oldest time stamp. The above-described processing of writing the side data to the secondary storage volume 31 cannot be executed.
Therefore, a problem may occur that the secondary storage device 3 cannot execute the above processing to acquire the backup completion time (consistency time) in the data multiplexing system.

The secondary storage device 3 is provided with another primary storage device 2-0 that can transfer secondary data at high speed (or normally).
/ 2-1 / 2-2 (2-0, 2-2 in this example)
Secondary data is sequentially received. Therefore, unprocessed data accumulates only in the corresponding queues 200/210/220 (in this example, the queues 200 and 220 for 2-0 and 2-2). For example, as shown in FIG. An imbalance occurs between the matrices 200, 210, 220. As a result, for example, one queue 200 /
210/220 (in this example, the queue 200 for 2-0) becomes full, and the queue 200/210
/ 220 corresponding to the primary storage device 2-0 / 2-1 / 2-
2 (in this example, the primary storage device 2-0), the secondary data cannot be received any more.

In order to cope with such a problem, the secondary storage device 3 stores, for example, (i) a certain queue 200/210 /
(Ii) the amount of data included in the 2-0 queue 200 exceeds a set threshold as shown in FIG. 3; The ratio of unprocessed data among 200, 210 and 220 exceeds the set ratio, and (iii) the queues 200 and 2
The queue 200/21 indicates that the remaining capacity of the cache memory 34 provided with 10, 220 is less than a set value.
0/220 or that the arrival status of the secondary data managed in the cache memory 34 has reached the set condition (or that it has become unbalanced). Then, upon detecting that the above condition has been reached, the secondary storage device 3 shifts to a temporary processing mode as described below.

<First Temporary Processing Mode> In the first temporary processing mode, the primary storage device 2-0 / 2-
Upon detecting that the arrival status of the secondary data from 1 / 2-2 has reached the set condition, the secondary storage device 3 sends the secondary storage device 3 to the primary storage device 2-0 / 2-1 / 2-2. While instructing to stop the transfer of the secondary data, the other primary storage device 2-0 /
The secondary data from 2-1 / 2-2 is written to the secondary storage volume 31 as usual, and the backup completion time (consistency time) is obtained.

In other words, the secondary storage device 3 is different from the primary storage device (primary storage device 2-0 in the example of FIG. 3).
A command to instruct to stop the transfer of the secondary data is transmitted.

The primary storage device (primary storage device 2-0 in the example of FIG. 3) which has received this instruction stops the transfer of the secondary data and also transfers the difference data that has not been transferred to the secondary storage device 3. Start grasping. In this case, the primary storage device 2-0
For example, the difference data may be stored in the cache memory 24 or another suitable storage medium (not shown). Alternatively, a difference bitmap (not shown) indicating the storage position of the untransferred data in the primary storage volume 21 is provided in, for example, the cache memory 24 or another appropriate storage medium (not shown), and the secondary data is not transferred. In order to indicate that there is, a bit corresponding to the storage position of the untransferred data on the primary storage volume 21 in the difference bitmap may be turned ON.

On the other hand, the secondary storage device 3 receives secondary data as usual from other primary storage devices (2-1 and 2-2 in the example of FIG. 3). Then, each primary storage device 2-0,
Sub-side data from all of 2-1 and 2-2 is stored in each queue 2
00, 210, 220 (ie, FIG. 2
When the state of (B) is reached), the secondary storage device 3 checks each of the queues 200, 210, and 220 from the head side as usual, and based on the time stamp attached to each secondary data, Transfer the data to the corresponding secondary storage volume 3
1 are written in the order of the timestamp time.

Further, the secondary storage device 3 uses the time stamp of the secondary data lastly written to the secondary storage volume 31 as the backup guaranteed time (consistency time) of the entire data multiplexing system as usual. ,
The data is stored in the cache memory 34 or another appropriate storage medium (not shown).

When the processing of the secondary data in the queue 200 progresses and the unbalanced state (for example, the state shown in FIG. 3) between the respective queues 200, 210 and 220 is resolved, the secondary storage device 3 An instruction is transmitted to the side storage device 2-0 to transfer the untransferred differential data in the temporary processing mode and to restart the transfer of the secondary data as usual.

According to the first temporary processing mode, for example, in each of the primary storage devices 2-0 while consistently grasping and guaranteeing up to which time data has been backed up in the entire data multiplexing system, it is guaranteed. , 2-1 and 2-2, it is possible to eliminate the unbalanced state of the arrival status of the sub-side data from the sub-data.

<Second temporary processing mode> In the second temporary processing mode, the primary storage device 2-0 / 2-
When detecting that the arrival status of the secondary data from 1 / 2-2 has reached the set condition, the secondary storage device 3 is transferred from each of the primary storage devices 2-0, 2-1 and 2-2. The incoming secondary data is not processed in chronological order based on the time stamp, but is written to the secondary storage volume 31 in the order of arrival.

FIG. 3 will be described as an example. When the mode shifts to the second temporary processing mode, the secondary storage device 3 first stores the start time when the mode shifts to the temporary processing mode in the cache memory 34 or an appropriate storage medium (not shown). The secondary storage device 3 does not wait for the secondary data to arrive from the primary storage device 2-1 and the secondary data to be arranged in each of the queues 200, 210, and 220. Is written to the secondary storage volume 31.

In the second temporary processing mode, the secondary data is not processed in chronological order based on the time stamp, but in the secondary storage volume 31 in the order of arrival.
In the entire system (that is, across the primary storage devices 2-0, 2-1 and 2-2).
It is not possible to consistently grasp up to which time data the secondary storage device 3 has completed the backup. Therefore, when shifting to the second temporary processing mode, the secondary storage device 3 acquires the time stamp of the secondary data written to the secondary storage volume 31 as the backup guaranteed time (consistency time) of the entire system. Is not performed.

When the processing of the secondary data in the queue 200 progresses and the unbalanced state (for example, the state shown in FIG. 3) between the queues 200, 210, and 220 is eliminated, the secondary storage device 3 The second temporary processing mode is ended, and the processing returns to the normal processing mode. At this time, the secondary storage device 3 stores the end time at which the temporary processing mode has ended in the cache memory 34.
Alternatively, it is stored in an appropriate storage medium (not shown).

According to the second temporary processing mode, for example, each primary storage device 2-0, 2-1 and 2-2 can be transferred to each primary storage device without interrupting the transfer of the secondary data. It is possible to eliminate the unbalanced state of the arrival status of the sub-side data from the side storage devices 2-0, 2-1 and 2-2. Further, since the start time and end time of the second temporary processing mode are stored in the secondary storage device 3, the user can know during which time the secondary data is not processed in chronological order. .

<Third Temporary Processing Mode> In the third temporary processing mode, the primary storage device 2-0 / 2-
When the secondary storage device 3 detects that the arrival status of the secondary data from 1 / 2-2 has reached the set condition, the secondary storage device 3 determines that the host computer 1 has the primary storage device 2-0 / 2-1-2-2. 2
While the transmission of data to the secondary storage device 2-0 is stopped, the secondary data from the other primary storage device 2-0 / 2-1 / 2-2 is written to the secondary storage volume 31 as usual, and the backup completion time ( Consistency time).

That is, the secondary storage device 3 is connected to the primary storage device (the primary storage device 2-0 in the example of FIG. 3).
The host computer 1 transmits a command instructing to stop transmitting data to the primary storage device 2-0.

The primary storage device 2-0 receiving this command
Sends an instruction to the host computer 1 to stop data transmission. The host computer 1 receiving this command stops transmitting data to the primary storage device 2-0.

Thereafter, if the secondary data which has not been transferred to the secondary storage device 3 exists in the cache memory 24, the primary storage device 2-0 stores the secondary data as usual.
Transfer to

The secondary storage device 3 receives the secondary data as usual. Then, each primary storage device 2-0, 2-1,
The secondary data from all of 2-2 is in each queue 200,2
When the data is stored in the queues 10 and 220 (that is, when the state shown in FIG. 2B is reached), the secondary storage device 3 checks the queues 200, 210 and 220 from the top as usual, and Based on the time stamp attached to the data,
The secondary data is written to the corresponding secondary storage volume 31 in ascending order of the time stamp.

As usual, the secondary storage device 3 uses the time stamp of the secondary data last written in the secondary storage volume 31 as the backup guaranteed time (consistency time) of the entire data multiplexing system. ,
The data is stored in the cache memory 34 or another appropriate storage medium (not shown).

When the processing of the secondary data of the queue 200 proceeds and the unbalanced state (for example, the state shown in FIG. 3) between the queues 200, 210, and 220 is resolved, the secondary storage device 3 An instruction is sent to the side storage device 2-0 to instruct the host computer 1 to resume transmission of data to the primary storage device 2-0 as usual.

According to the third temporary processing mode, for example, in each data multiplexing system, each primary storage device 2-0 is consistently grasped and assured up to which time data has been backed up in the entire data multiplexing system. , 2-1 and 2-2, it is possible to eliminate the unbalanced state of the arrival state of the sub-side data from the sub-side data.

<Others> Designation information for designating which temporary processing should be executed by the secondary storage device 3 is stored in, for example, the host computer 1 operated by the user or the primary storage device connected to the secondary storage device 3 or a management storage device. May be transmitted from the computer (not shown) or the like to the secondary storage device 3 in advance and stored, and the temporary processing may be executed according to the designation information. With such a configuration, a user using the present data multiplexing system can freely designate temporary processing according to needs. In addition, the specification of temporary processing is
The primary storage devices 2-0, 2-1 and 2-2 are replaced with the secondary storage device 3
It may be performed when connecting to.

Alternatively, a program or the like for executing the above-mentioned temporary processing may be prepared in the secondary storage device 3 in advance, and the secondary storage device 3 may select and execute an appropriate temporary processing mode according to conditions. . With such a configuration, the temporary processing mode is flexibly selected in order to eliminate the unbalanced state of the arrival status of the secondary data from each of the primary storage devices 2-0, 2-1 and 2-2. Can be performed.

Further, in order to notify the transition to the temporary processing mode, the secondary storage device 3 is used as the external notification means.
The alarm lamp provided in the sub-storage device 3 may be turned on or blinking, or an alarm may be sounded.
May be transmitted to the host computer 1 or the primary storage device connected to the secondary storage device 3 or the management computer (not shown) as the external notification means.

[0070]

According to the present invention, in a data multiplexing system including a plurality of primary storage devices and secondary storage devices, the processing capability of the entire system can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an embodiment of a data multiplexing system according to the present invention.

FIG. 2 is a diagram showing a queue included in a secondary storage device in one embodiment of the data multiplexing system according to the present invention.

FIG. 3 is a diagram schematically showing a data transfer state in one embodiment of the data multiplexing system of the present invention.

[Explanation of symbols]

1 Host computer 2-0, 2-1 and 2-2 Primary storage device 3 Secondary storage device 20,30 storage controller 21 Primary storage volume 31 Secondary storage volume

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Toru Suzuki             322-2 Nakazato, Odawara-shi, Kanagawa Stock             Hitachi, Ltd. RAID System Division F term (reference) 5B005 JJ01 MM11 WW02 WW15                 5B065 BA01 EA02 EA12

Claims (12)

[Claims] 1. A primary storage device comprising at least one primary storage volume, and a secondary storage device comprising at least one secondary storage volume and connected to the primary storage devices, By transferring the secondary data having the same content as the primary data stored in the primary storage volume of each primary storage device to the secondary storage device and storing it in the secondary storage volume of the secondary storage device, ,
A control method in a data multiplexing system for multiplex-holding data in the primary storage device and the secondary storage device, wherein the secondary storage device manages an arrival status of the secondary data. A, the secondary storage device, the primary data and the secondary storage device for indicating the time at which the host computer connected to the plurality of primary storage devices transmitted the primary data to each primary storage device. A step B of writing the received secondary data to the secondary storage volume in chronological order based on the time information attached to the data; and setting the arrival status of the secondary data from a certain primary storage device. A step C of performing a condition departure process for causing the arrival status of the secondary data from the certain primary storage device to deviate from the set condition when the set condition is satisfied; Comprising, a control method of a data multiplexing system. 2. When the secondary data to be written to the secondary storage volume received from all of the specific primary storage devices is accumulated in the secondary storage device,
The secondary storage device executes the step B, and when the step B is executed, the secondary storage device acquires the time information of the secondary data last written in the secondary storage volume. A method for controlling a data multiplexing system according to claim 1. 3. The condition departure process in the step C, wherein the secondary storage device stops the process B, and stores the secondary data in the secondary storage device in the order transferred from each of the primary storage devices. 3. The control method for a data multiplexing system according to claim 1, wherein the control method is a process of writing to a volume. 4. The condition departure process in the step C, wherein the secondary storage device transmits an instruction to the certain primary storage device to stop transfer of the secondary data, 3. The control method for a data multiplexing system according to claim 1, wherein the certain primary storage device that has received the command is a process of ascertaining data that has not been transferred to the secondary storage device. 5. The condition departure process in the step C, wherein the secondary storage device issues an instruction that causes the host computer to stop transmitting the primary data to the certain primary storage device. 3. The control method for a data multiplexing system according to claim 1, wherein the process is a process of transmitting data to a certain primary storage device. 6. The condition release process in the step C, the secondary storage device stops the process B, and stores the secondary data in the secondary storage order in the order transferred from each of the primary storage devices. A process of writing to a volume, the secondary storage device transmits an instruction to the certain primary storage device to stop the transfer of the secondary data, and the certain primary storage device receives the instruction. A process in which a side storage device grasps data that has not been transferred to the secondary storage device; and a process in which the secondary storage device stops the host computer from transmitting the primary data to the certain primary storage device. The secondary storage device receives designation information for designating which of the following processes is to be executed: a process of transmitting an instruction that causes the command to be transmitted to the certain primary storage device, and the process C is executed in accordance with the designation information. Claim 1 3. The method for controlling a data multiplexing system according to claim 2. 7. The condition release process in the step C, the secondary storage device stops the process B and stores the secondary data in the secondary storage order in the order transferred from each of the primary storage devices. A process of writing to a volume, the secondary storage device transmits an instruction to the certain primary storage device to stop the transfer of the secondary data, and the certain primary storage device receives the instruction. A process in which a side storage device grasps data that has not been transferred to the secondary storage device; and a process in which the secondary storage device stops the host computer from transmitting the primary data to the certain primary storage device. 3. The control method for a data multiplexing system according to claim 1, wherein the secondary storage device selects and executes any one of a process of transmitting an instruction that triggers the instruction to the certain primary storage device. . 8. When the step C is executed, the secondary storage device indicates to the effect that the secondary storage device is connected to the primary storage device, the host computer, the secondary storage device, and the secondary storage device. The control method for a data multiplexing system according to any one of claims 1 to 7, further comprising a step E of notifying an external notifying means selected from a group consisting of alarm means provided in the data multiplexing system. 9. The set condition of the arrival status of the secondary data from the certain primary storage device, wherein the amount of the secondary data from the certain primary storage device exceeds a set value; The ratio of the amount of the secondary data from each of the primary storage devices has exceeded the set ratio, and the remaining capacity of the storage medium storing the secondary data from each of the primary storage devices has become less than the set value. The method according to claim 1, wherein the method is selected from the group consisting of: 10. A primary storage device comprising at least one primary storage volume, and a secondary storage device comprising at least one secondary storage volume and connected to said primary storage devices, By transferring the secondary data having the same content as the primary data stored in the primary storage volume of each primary storage device to the secondary storage device and storing it in the secondary storage volume of the secondary storage device, A data multiplexing system for multiplexing data in the primary storage device and the secondary storage device, wherein the secondary storage device manages an arrival status of the secondary data; The primary data and the secondary data are added to the primary data to indicate the time at which the host computer connected to the multiple primary storage devices transmitted the primary data to each of the primary storage devices. Means for writing the received secondary data to the secondary storage volume in chronological order based on the received time information, and a condition in which the arrival status of the secondary data from a certain primary storage device is set. 2. The data according to claim 1, further comprising: means for executing a condition departure process for satisfying the condition so that the arrival status of the secondary data from the certain primary storage device deviates from the set condition. 3. The data multiplexing system used in the control method of the multiplexing system. 11. A primary storage device comprising at least one primary storage volume, and a secondary storage device comprising at least one secondary storage volume and connected to the primary storage devices, By transferring the secondary data having the same content as the primary data stored in the primary storage volume of each primary storage device to the secondary storage device and storing it in the secondary storage volume of the secondary storage device, The secondary storage device in a data multiplexing system for multiplexing data in the primary storage device and the secondary storage device, wherein the secondary storage device has an arrival status of the secondary data. Means for managing the primary data, the host computer connected to the plurality of primary storage devices transmitting the primary data to each of the primary storage devices. Means for writing the received secondary data to the secondary storage volume in chronological order based on the time information attached to the secondary data, and arrival of the secondary data from a primary storage device Means for executing a condition departure process for causing the arrival status of the secondary data from the certain primary storage device to deviate from the set condition when the status satisfies a set condition. 2. The secondary storage device used in the control method for a data multiplexing system according to claim 1. 12. The secondary storage device used in the method of controlling a data multiplexing system according to claim 1, wherein: a step A of managing an arrival status of the secondary data; and a connection to the plurality of primary storage devices. Based on time information attached to the primary data and the secondary data to indicate the time at which the host computer transmitted the primary data to each of the primary storage devices, the received secondary data is time-based. Step B of writing to the secondary storage volume in the order of the sequence
When the arrival status of the secondary data from a certain primary storage device satisfies a set condition, the arrival status of the secondary data from the certain primary storage device is the set condition. And a step C of executing a condition departure process for deviating from step C.