JP5170169B2 - Remote copy processing system, processing method, and processing program between disk array devices - Google Patents

Description

  The present invention relates to a remote copy processing system and a remote copy processing between disk array devices that enable copying with guaranteed order to a remote site between a main site and a remote site of a storage configuration connected via a communication line. The present invention relates to a method and a processing program.

  2. Description of the Related Art Conventionally, a data replication system is known in which data is multiplexed and held by remote copying between disk array apparatuses installed at a main site and a remote site, respectively. Data transfer methods for executing the remote copy processing are roughly classified into a synchronous copy method, a semi-synchronous order guaranteed copy method, and an asynchronous copy method.

  Of these, the synchronous copy method writes the update IO (IN, OUT) from the host to the logical disk on the remote site in synchronization with the write to the logical disk on the main site side, and completes writing to both logical disks. This is a method of returning the completion report to the host later.

  The semi-synchronous order-guaranteed copy method writes the update IO from the host to the logical disk at the main site and saves the update IO in the order-guaranteed buffer at the main site. At this time (update IO from the host to the logical disk at the remote site) The end report is returned to the host. Thereafter, the updated IO stored in the order guarantee buffer is periodically applied to the logical disk at the remote site. Here, the order guarantee means that the data update order at the remote site is the same as the data update order at the main site in order to ensure data consistency.

  Asynchronous copy method writes update IO from the host to the logical disk at the main site, and returns the completion report to the host when the write is completed, and the only difference is the range of the logical disk at the main site that has been updated. The update data is stored as information, and the update data is written to the remote site according to the capacity of the communication line, and the range in which this difference exists is remotely copied asynchronously with the writing to the logical disk at the main site.

  These methods are as follows from the viewpoint of data loss in the remote chassis when a disaster or the like occurs on the main site side and the main site loses its function.

  In the synchronous copy method, data is written and stored in the logical disk at the remote site in synchronization with the writing of data on the logical disk at the main site. Therefore, the amount of data loss is the smallest among these three methods.

  Next, in the semi-synchronous order-guaranteed copy method, the erasure amount is the maximum amount stored in the order-guaranteed buffer, which is larger than that in the synchronous copy method.

  In the asynchronous copy method, when there is a lot of difference information in the update range, the maximum amount of the difference information is lost when the remote copy is not completed when a disaster occurs.

  These methods are as follows from the viewpoint of response to the host.

  The synchronous copy method responds to the host after writing to the remote chassis is completed, so there are problems with response delay due to the line distance from the main site to the remote site, and response delay due to the capacity of the line to which data is transferred. Become.

  Next, the semi-synchronous order-guaranteed copy method responds to the host when the copying to the order-guaranteed buffer is completed, so that the responsiveness is better than the synchronous copy method. However, when writing exceeding the line capacity occurs, if there is not enough buffer for order guarantee, there is a disadvantage that the buffer overflows and the buffer waiting state occurs.

  In the asynchronous copy method, a response is made when writing to the logical disk at the main site is completed, and only the update status is stored, so there is no delay in response to the host. However, in the asynchronous copy method, the update data at the main site is managed as difference information only for the address at which the logical disk was written, and the main site can be remotely controlled without guaranteeing the update data temporal writing order. Sending data to the site sequentially. In addition, the amount of data to be updated is increasing, and updating is performed on duplicate address data on the logical disk. Therefore, when there is a difference (when the difference information has not been sent to the remote site), the data at both sites is inconsistent, so a disaster occurred at the main site and the logical disk data was lost. In this case, the data at the main site cannot be restored using the data at the remote site.

  By the way, as this type of related technology, for example, Patent Documents 1 to 2 shown below can be cited.

  Patent Document 1 discloses an I / O in which a disk array device at a primary site and a secondary site are connected by a communication line, and a disk array device at a primary site writes update data to a cache when there is a write request for update data. O processing unit, group registration means for registering a group of logical disks that guarantees data consistency, and multiple updates to the storage buffer by copying the update data written in the cache so that they are packed into the storage buffer in order from the top A technology has been proposed that includes a concentrator that transfers the packing data to the disk array device at the secondary site when the data is packed, thereby executing a remote data copy method with the disk array device at the secondary site.

  Patent Document 2 discloses a technique in which a write request to a disk being backed up is trapped regarding storage of digital data. According to this technique, if the disk location being written has not yet been backed up, the original contents are copied to an alternative temporary storage so that the backup can continue. Eventually, this temporary storage is also copied to the backup.

JP 2003-167684 A JP-T-2004-504645

  However, in the technique disclosed in Patent Document 1, the packing data is only asynchronously transferred to the disk array device at the secondary site when a plurality of update data is packed in the storage buffer, and the order is guaranteed. We couldn't provide a function that guarantees the order with a few buffers. In addition, since all control information and update data for order guarantee are stored in the buffer, there is a problem that the buffer overflows due to the relationship between the buffer amount, the line capacity between the disk array devices, and the update data amount from the host. It was.

  In addition, the technique disclosed in Patent Document 2 intends to provide a temporary data save area for the purpose of suppressing a write delay when data is written to the master disk during backup. It does not guarantee order.

[Object of invention]
Therefore, the present invention has been made in view of such circumstances, and a remote copy processing system, a remote copy processing method between disk array devices capable of realizing asynchronous order-guaranteed copying with a small capacity buffer, and The purpose is to provide a processing program.

In order to solve the above problems, a remote copy processing system between disk array devices according to the present invention is such that a disk array device at a main site and a disk array device at a remote site are connected via a remote line, and the disk array device at the main site A remote copy processing system between disk array devices for copying data stored in the disk array device at the remote site,
The disk array device at the main site is
When there is a request for writing update data from the host computer, at least the updated data of the update data write control information in synchronization with the storage process of the update data in the cache provided in the disk array device A transmission management buffer in which order guarantee information including update range information representing a range of
When there is an update data write request from the host computer, the update range information included in the order guarantee information regarding the update data of the request and the update data of the previous request from the host computer stored in the transmission management buffer Information duplication determination means for determining whether or not the update range information included in the order guarantee information regarding
When it is determined by the information duplication determination means that the update range information included in the order guarantee information regarding the two update data is duplicated, the update data of the previous request stored in the cache is read. A data buffer for transmission in which the read update data is stored;
Update data stored in the transmission data buffer and update data stored in the cache are copied to the remote site disk array device asynchronously with the update data storage processing in the main site disk array device. A transmission copy control means;
It is characterized by having.

In order to solve the above-mentioned problem, a remote copy processing method between disk array devices according to the present invention is such that a disk array device at a main site and a disk array device at a remote site are connected via a remote line, and the disk at the main site is In a remote copy processing system between disk array devices for copying data stored in an array device to a disk array device at the remote site,
When there is a write request for update data from the host computer, the update range information included in the order guarantee information related to the update data of the request and the previous request stored in the transmission management buffer provided in the disk array device at the main site Whether or not the update range information included in the order guarantee information related to the update data is duplicated is determined by the information duplication determination means equipped in the disk array device,
When it is determined by the information duplication determination means that the update range information included in the order guarantee information related to the two update data is duplicated, the I / O processing unit equipped in the disk array device performs the disk Storing the update data of the previous request from the host computer stored in the cache provided in the array device in a transmission data buffer provided in the disk array device;
Subsequently, the I / O processing unit stores in the cache update data relating to the request for which update data has been requested from the host computer, and also transmits order guarantee information relating to the update data of the request to the transmission management Memorize it in the buffer,
The transmission copy control means installed in the disk array device at the main site sends the update data stored in the transmission data buffer and the update data stored in the cache to the disk array device at the remote site. The update data storage process in the disk array device at the main site is copied asynchronously.

In order to solve the above problems, a remote copy processing program between disk array devices according to the present invention is such that a main site disk array device and a remote site disk array device are connected via a remote line, and the main site In a remote copy processing system between disk array devices for copying data stored in a disk array device to a disk array device at the remote site,
An update data storage processing function for storing the update data in a cache provided in the disk array device of the main site when there is a write request for update data from the host computer;
Order guarantee information storage processing for storing order guarantee information including update range information related to the update data in a transmission management buffer provided in the disk array device of the main site in synchronization with the update data storage processing to the cache function,
When there is an update data write request from the host computer, the update range information included in the order guarantee information related to the update data of the request, and the update data of the previous request from the host computer stored in the transmission management buffer Information duplication judgment function for judging whether or not the update range information included in the order guarantee information related to
When it is determined by the information duplication determination function that the update range information included in the order guarantee information regarding the two update data is duplicated, the update data stored in the cache is read and the read update A duplicate update data storage processing function for storing data in a transmission data buffer provided in the disk array device of the main site;
Update data stored in the transmission data buffer and update data stored in the cache are copied to the remote site disk array device asynchronously with the update data storage processing in the main site disk array device. With remote copy function,
Each of these functions is realized by a computer.

  According to the present invention, when there is an update data write request from the host computer, not all the requested update data is stored in the buffer, but only the update data that overlaps the previous update data for which there was a write request. Is stored in the buffer, so that remote copy that can guarantee the order asynchronously with a small amount of buffer memory can be realized.

1 is a block diagram showing an embodiment of a remote copy processing system between disk array devices according to the present invention. FIG. It is a chart which shows the example of the order guarantee information memorize | stored in the management buffer for transmission in embodiment disclosed in FIG. 2 is a flowchart showing a processing operation of a data update request from a host in FIG. 3 is a chart showing order guarantee information stored in a table of a transmission management buffer when a duplicate update data write request is issued from a host in FIG. 1. 3 is a flowchart showing a copy processing operation of update data to a remote site disclosed in FIG. 1; It is a chart which shows the example of the position information of the update data memorize | stored in the table of the data buffer for transmission, and the data content. 2 is a flowchart showing a processing operation when copying to a remote site in FIG. 1 fails.

  Hereinafter, an embodiment of a remote copy processing system between disk array devices according to the present invention will be described with reference to FIGS.

  As shown in the block diagram of FIG. 1, the main site 1 and the remote site 2 are connected via a remote line (communication line) 40.

  The main site 1 includes a host (host computer) 10 that functions as an information processing device, and a disk array device 20 as a data storage device that is communicably connected to the host 10 via a communication network. . Similarly, the remote site 2 includes a host 15 and a disk array device 30. The main site 1 and the remote site 2 are installed in, for example, a remote place as a measure against information loss due to a disaster.

  The hosts 10 and 15 transmit read request commands, write request commands, and the like to the disk array devices 20 and 30. The hosts 10 and 15 may be any computer such as a server, a network desktop, a laptop computer, an information device having a wireless / wired communication function such as a large computer system, or a similar computer.

  The disk array device 20 functions as an input / output (I / O) processing unit 21 that performs update data write processing, a cache 22 that functions as a temporary storage unit for information, and a unit that performs logical disk group registration. It includes a group registration means 25, concentrators 26 and 27 for controlling data update order guarantees, a group 23 consisting of logical disks A and B and a group 24 consisting of logical disks C and D accessed from the host 10. Has been.

  The I / O processing unit 21 has a function of writing update data to a cache 22 provided in the disk array device 20 when there is a write request for update data from the host 10. In addition, when the execution of the process of writing the update data to the cache 22 is completed, the I / O processing unit 21 returns a response to the update data write request to the host 10 before executing the remote copy to the remote site 2. .

  The cache 22 is an internal cache of the disk array device 20 and functions as a temporary storage unit for information. Update data requested from the host 10 is temporarily stored in the cache 22 and further written to a physical disk (hard disk) by background processing.

  The logical disks A, B, C, and D are disks that are accessed from the hosts 10 and 15 and have a combination of a plurality of physical disks to provide redundancy.

  The logical disks A and B at the main site 1 and the remote site 2 constitute one database and are registered as a logical disk group 23 that guarantees data consistency. The logical disks C and D also constitute one database at each site and are registered as a logical disk group 24 that guarantees data consistency.

  The group registration means 25 is a means for registering a group of logical disks that guarantees the data consistency.

  The concentrator 26 is a line concentrator provided with a transmission function for controlling data update order guarantee in asynchronous transfer. When data is copied between the disk array devices via the remote line 40, the data update order in the disk array device 30 at the remote site 2 is changed to the disk array device 20 at the main site 1 in order to guarantee data consistency. It is necessary to carry out in the same manner as the order of data update in. This guarantee of order is called data update order guarantee.

  The concentrator 26 receives information duplication judgment means 26A for judging whether or not requests from the host 10 are duplicated, transmission copy control means 26B for copying update data to the remote site 2, and order guarantee information (control information). A transmission management buffer (order guarantee buffer) 26C for saving and a transmission data buffer 26D for saving update data are included.

  The concentrator 27 is a concentrator provided separately from the concentrator 26, and the content of the function is the same as that of the concentrator 26. Asynchronous transfer means that an end response signal is returned to the host as soon as the data update in the disk array device 20 at the main site 1 is completed, and remote copy of data to the disk array device 30 at the remote site 2 is performed. A copy method that is performed asynchronously.

  The transmission management buffer 26C constituting a part of the concentrator 26 is a buffer for storing the order guarantee information. The order guarantee information is control information for making the data update order at the remote site 2 the same as the data update order at the main site 1, and the disk array device 20 at the remote site 2 from the disk array device 20 at the main site 1. Data transfer to 30 is managed. Every time an update IO (IN, OUT) command is received from the host, the order guarantee information regarding the update data is stored in the transmission management buffer 26C. Each information constituting the order guarantee information will be described later. The transmission management buffer 26C is configured by a memory for storing information, but may be configured by, for example, a disk that is a readable / writable medium.

  The transmission data buffer 26D is a buffer for storing update data transferred from the disk array device 20 at the main site 1 to the disk array device 30 at the remote site 2. The transmission data buffer 26D is composed of a memory for storing data, but may be composed of, for example, a disk that is a readable / writable medium.

  In FIG. 1, the transmission management buffer 26C and the transmission data buffer 26D are shown as separate buffers. However, the present invention is not limited to this. For example, one transmission buffer is provided and the order is guaranteed in the buffer. The transmission management buffer 26C area for storing information and the transmission data buffer 26D area for storing update data may be provided.

  The information duplication determination unit 26A is a unit that determines whether or not the range of the write request from the host 10 overlaps with the order guarantee information stored in the transmission management buffer 26C.

  The transmission copy control unit 26B is a unit that performs the guaranteed copy of the update data to the remote site 2 based on the ordered guarantee information stored in the transmission management buffer 26C. Details will be described later in (3) Copy operation to remote site.

  When a plurality of databases are stored in the disk array device 20, a plurality of logical disk groups that guarantee data consistency are registered (groups 23 and 24), and each concentrator 26, 27 are provided.

  The disk array device 30 includes an I / O processing unit 31, a cache 32, a group 33 composed of logical disks A and B, and a group 34 composed of logical disks C and D. The functions of the parts are the same as the functions of the corresponding constituent parts of the disk array device 20 described above.

  Next, the operation of the remote copy processing system between the disk array devices will be described in detail.

(1) Group Registration The group registration means 25 shown in FIG. 1 registers a logical disk group that guarantees data consistency. Specifically, the number of each group and the logical disk belonging to each group, and the number of the concentrator assigned corresponding to each group are registered.

  In this embodiment, each of the logical disks A and B and the logical disks C and D constitutes one database. Therefore, the logical disks A and B are grouped into the logical disk group 23, and the concentrator 26 is provided correspondingly. assign. Further, the logical disks C and D are set as a logical disk group 24, and a concentrator 27 is allocated correspondingly.

  Therefore, in this embodiment, the group registering means 25 registers the group 23 composed of the logical disks A and B and the concentrator 26 assigned corresponding thereto. In addition, a group 24 composed of logical disks C and D and a concentrator 27 assigned in correspondence therewith are registered.

  The concentrators 26 and 27 have copy status information for determining whether or not they are ready to copy (transfer) update data to the remote site 2 side. When copying to the remote site 2 fails, this information is rewritten (details will be described later). Note that the copy state initially stored in the concentrator is set to the copy ready state.

(2) Data Update Operation The update IO (IN, OUT) from the host 10 is composed of order guarantee information that is control information for updating data and update data of the data to be updated. The write information to the logical disk group 23 requested from the host 10 is stored in the transmission management buffer 26C as the order guarantee information indicating the update status. As shown in the buffer table of FIG. 2, the order guarantee information includes an “order guarantee number” 51 indicating the data update order, the write order to the logical disk, and the “logical disk number” indicating the number of the logical disk to be written. 52, an “update range” 53 representing the data update range of the logical disk, a “copy destination disk array device” 54 representing the storage device (disk array device) to which the data is copied, and a logical disk to which the data is to be copied “Copy destination logical disk number” 55, “Data copy presence / absence to buffer” 56 indicating whether or not the data has been copied to the transmission data buffer 26 D, and “Copy data storage destination” indicating the data storage destination 57. Note that the “logical disk number” 52 and the “update range” 53 are requested to be transmitted as control information from the host 10 to the disk array device 20 together with the update data.

  The operation in the update process from the host will be described based on the flowchart of FIG.

  In the disk array device 20 at the main site 1, for example, it is assumed that there is a request for writing update data (Z0) to the logical disk A from the host 10. At this time, it is assumed that the previous update data for which the copy processing to the remote site 2 has not yet been completed remains in the disk array device 20 of the main site 1.

  First, the I / O processing unit 21 receives a request from the host 10. The I / O processing unit 21 that has received the request copies “whether or not the concentrator 26 is ready to perform the copy process” based on the recorded items of the concentrator 26 that manages the group 23 of the logical disk A. State determination is performed (step S101). The concentrator 26 is registered with one of the copy processing enabled / disabled states. This point will be described later in the column of (4) Operation when copying fails.

  If the result of determination in step S101 is “copy not possible” in which copy processing cannot be performed, it is determined that the concentrator 26 is in an abnormal (failed) state, and the processing for the write request from the host 10 ends abnormally. Is done.

  On the other hand, if the result of the determination is “copying possible”, the information duplication determining unit 26A of the disk array device 20 subsequently writes the write range to the logical disk A (update data requested to be written). Whether or not the “update range” of the order guarantee information (Z01) relating to (Z0) overlaps with the order guarantee information relating to the update data for which there was a previous write request registered and stored in the transmission management buffer 26C. Is determined (step S102). However, the duplication confirmation target here is registered as “None” for “Data copy presence / absence 56 to buffer (data buffer for transmission)” (see FIG. 2) stored in the transmission management buffer 26C. Order guarantee information.

  If the result of determination in step S102 is “no duplication”, the I / O processing unit 21 performs processing for writing the current update data (Z0) requested to be written from the host 10 to the cache 22 (step S104). . The update data (Z0) written to the cache 22 is written to the logical disk A by background processing.

  Further, the I / O processing unit 21 performs “order guarantee number” 51, “logical disk number” 52, “update range” 53, and “copy destination disk array device” 54 in the table of the transmission management buffer 26C shown in FIG. , “Copy destination logical disk number” 55, “data copy presence / absence to buffer” 56, and “copy data storage destination” 57, an order representing the update status regarding the update data (Z 0) while guaranteeing the order Each data “0001”, “A”, “0000-0001”, “30”, “A”, “none”, “invalid” of the guarantee information (Z01) is stored (step S105). Here, in the column of the order guarantee number 51, a serial number indicating the order of writing from the host 10 to the logical disk group 23 is stored.

  Next, in the disk array device 20 at the main site 1, for example, it is assumed that there is a request for writing update data (Z1) from the host 10 to the logical disk A.

  In this case, similarly to the case where the update data (Z0) is requested to be written to the logical disk A, the copy state is determined in the flowchart of FIG. 3 (step S101), and the determination result is the copy ready state. If there is, the overlap determination is performed (step S102).

  As a result of the duplication determination in step S102, if it is determined that the current update data (Z1) requested to be written overlaps with the previous update data (Z0) described above, first, the update data (Z0) is determined. The update data (Z0) written in the cache 22 in step S104 is copied (saved) to the transmission data buffer 26D provided in the concentrator 26 (step S103).

  Then, the order guarantee information (Z01) of the update data (Z0) shown in FIG. 2 stored in the transmission management buffer 26C table is rewritten with the order guarantee information (information of the row with the order guarantee number “0001”) shown in FIG. Remember. That is, as shown in the table of FIG. 4, the location information (9000-9001) of the transmission data buffer 26D in which the update data (Z0) is copied (saved) is stored in the "copy data storage destination" 57 column. Then, the “present” data is stored in the “data copy presence / absence to buffer” 56 column. It is possible to determine that the update data of the order guarantee number “0001” has been copied to the transmission data buffer 26D based on the “present” data stored in the “data copy presence / absence to buffer” 56 field. it can.

  Subsequently, the update data (Z1) requested to be written from the host 10 is written into the cache 22 (step S104). The update data (Z1) written to the cache 22 is written to the logical disk A by background processing.

  Then, the “order guarantee number” 51, “logical disk number” 52, “update range” 53, “copy destination disk array device” 54, “copy destination logical disk number” 55 of the transmission management buffer 26C shown in FIG. In each column of “data copy presence / absence to buffer” 56 and “copy data storage destination” 57, each data “0002”, “A”, “0000-0002” of the order guarantee information (Z11) related to the update data (Z1) is stored. “,” “30,” “A,” “none,” and “invalid” are stored (step S105). With such a processing operation, data is accumulated in the transmission data buffer 26D only when the host 10 makes a write request to the same area, so that the capacity of the buffer to be used can be reduced.

  If the update data (Z1) is not duplicated with the update data (Z0) as a result of the duplication determination in step S102, the update data (Z1) is related to the update data (Z0) as in the process related to the update data (Z0). Steps S104 and S105 are performed. That is, the update data (Z1) is stored in the cache 22 in which the update data (Z0) is stored without saving the update data (Z0) in the transmission data buffer 26D.

(3) Copy Operation to Remote Site Data copy operation processing to the remote site will be described based on the flowchart of FIG.
The transmission copy control means 26B provided in the concentrator 26 operates periodically (for example, every predetermined time, every time there is a request to write from the host, etc.), and guarantees the order of the update data to the remote site 2 based on the order guarantee information. Copy processing is being executed.

  First, the transmission copy control means 26B performs a copy status determination of “whether or not the concentrator 26 is ready for copying” based on the recorded items of the concentrator 26 that manages the logical disk group 23 (see FIG. Step S110).

  If the result of determination in step S110 is “copy not possible”, it is determined that the concentrator 26 is in an abnormal (failed) state, and the transmission copy control means 26B ends the copy process.

  On the other hand, if the result of the determination in step S110 is “copying possible”, then the transmission copy control means 26B, based on the order guarantee information stored in the transmission management buffer 26C, It is determined whether there is data to be copied to the remote site 2 (step S111). This determination can be made based on whether or not there is data that is not “invalid” in the “order guarantee number” 51 column of the transmission management buffer 26C.

  If the result of the determination in step S111 is “no data to copy”, the transmission copy control means 26B ends the copy process.

  On the other hand, if the result of the determination in step S111 is “there is data to be copied”, the transmission copy control means 26B displays the “data copy presence / absence to buffer” 56 column in the transmission management buffer 26C table. The presence / absence of copy data is determined based on the information (“present / not present”) stored in (step S112).

  Here, it is assumed that the order guarantee information shown in FIG. 4 is stored in the transmission management buffer 26C. The order guarantee information shown in FIG. 4 is the order guarantee information (Z01) and (Z11) related to the update data (Z0) and (Z1) requested to be written by the host 10 in the above-mentioned “(2) Data update operation”. is there. In this case, since there are data “0001” and “0002” that are not “invalid” in the column of “order guarantee number” 51, the determination result of step S111 is determined to be “copy present”.

  The data determination of the transmission management buffer 26C (FIG. 4) is determined in order from the younger number (hereinafter referred to as “young number”) in the “order guarantee number” 51 column. Therefore, first, determination is made based on the data of the young number “0001”, and “Yes” data is stored in the “data copy presence / absence to buffer” 56 column of this line. The result is determined as “copy data present”.

  The copy data is stored in the transmission data buffer 26D, and the buffer number (9000-9001) of the storage destination is shown in the “copy data storage destination” 57 column of FIG. FIG. 6 shows a table of the transmission data buffer 26D. As shown in FIG. 6, the table stores a buffer number and update data (Z0). Specifically, “data in logical disk A update range 0000” is stored in buffer number “9000”, and “data in logical disk A update range 0001” is stored in buffer number “9001”. .

  If it is determined that there is “copy data” in the determination in step S112, the transmission copy control means 26B uses the update data (Z0) copied (saved) in the transmission data buffer 26D to the disk at the remote site 2. Remote copy is performed to the array apparatus 30 via the remote line 40 (step S113). Further, the transmission copy control means 26B reads out the order guarantee information relating to the update data (Z0) from the transmission management buffer 26C and performs remote copy to the disk array device 30 at the remote site 2 via the remote line 40. Note that the update data (Z0) written to the disk array device 30 at the remote site 2 is stored in the logical disk A of the disk array device 30 by background processing (see the column “copy destination logical disk number” 55 in FIG. 4). Is written to.

  Subsequently, when the copying to the remote site 2 is successful / completed, a signal to that effect is returned from the remote site 2 side, so that the transmission copy control means 26B sends the “order guarantee number” in the transmission management buffer 26C. The data “0001” stored in the column 51 is rewritten to “invalid” (step S115), and the copy process is terminated.

  Next, when copy processing by the next transmission copy control means 26B that is periodically executed is started, copy state determination processing is performed in the flowchart of FIG. 5 in the same manner as the copy processing described above (step S110). If the determination result indicates that copying is possible, the presence / absence of copying is determined (step S111), and if it is determined that copying is present, the presence / absence of copy data is determined (step S112).

  Here, it is assumed that the order guarantee information shown in FIG. 4 is stored in the transmission management buffer 26C. However, the data in the “order guarantee number” 51 column of the transmission management buffer 26C has been rewritten from “0001” to “invalid” by the previous copy process (step S115) by the transmission copy control means 26B.

  Then, the data in the row of the young number “0002”, which is the next lower number after the order guarantee number in FIG. 4, is read and determined. Since “invalid” is stored in the “copy data storage destination” 57 of the data in this row, the determination result in step S112 is determined to be “no copy data”. Then, as shown in FIG. 4, “None” is stored in “Copy to buffer” 56 in the young number “0002” in the “Sequence Assurance Number” column, so copy to the remote site 2. It can be determined that the data is not copied (saved) in the transmission data buffer and is stored in the logical disk A of the group 23. Accordingly, the transmission copy control means 26B reads the update data (Z1) stored in the logical disk A (or cache 22) from the corresponding area and remotely copies it to the disk array device 30 at the remote site 2 via the remote line 40. (Step S114).

  The update data (Z1) written to the disk array device 30 at the remote site 2 is written to the logical disk A (refer to the “copy destination logical disk number” 55 column in FIG. 4) by background processing.

  Subsequently, when the copying to the remote site 2 is successful / completed, a signal to that effect is returned from the remote site 2 side, so that the transmission copy control means 26B sends the “order guarantee number” in the transmission management buffer 26C. The data “0002” stored in the column 51 is rewritten to “invalid” (step S115), and the copy process is terminated.

  Further, the update data (Z0) is copied (saved) to the transmission data buffer 26D, and the update data (Z1) is stored in the cache 22, and the remote data of these update data (Z0) and (Z1) is stored. In the state where the remote copy processing to the site 2 has not been completed yet, when update data (Z2) is requested to be written further from the host 10, the above-described operation is as follows.

  Duplication determination is performed between the order guarantee information of the update data (Z1) stored in the cache 22 and the order guarantee information of the update data (Z2) requested to be written. If the result of determination is that there is an overlap, update data (Z1) is copied (saved) to the transmission data buffer 26D.

  Then, the position information of the saved transmission data buffer 26D is stored in the “copy data storage destination” 57 column of the order guarantee information (data in the row of the order guarantee number 51) regarding the update data (Z1) in FIG. “Yes” data is stored in the “data copy presence / absence to buffer” 56 column. The position information of the transmission data buffer 26D is stored from the buffer number 9002 following the buffer number 9001 shown in FIG. Specifically, the buffer number “9002” has “logical disk A update range 0000 data”, the buffer number “9003” has “logical disk A update range 0001 data”, and the buffer number “9004” has “logical disk”. "Data in the update range 0002 of A" is stored.

  Subsequently, the update data (Z2) requested to be written by the host 10 is written into the cache 22. Then, each data of the order guarantee information (Z21) relating to the update data (Z2) is stored in the table of the transmission management buffer 26C shown in FIG. The update data (Z2) written to the cache 22 is written to the logical disk A by background processing.

(4) Operation at Copy Failure The operation process when data copy to the remote site has failed will be described based on the flowchart of FIG.

  When the copy to the remote site 2 fails, the transmission copy control means 26B provided in the concentrator 26 determines whether or not the failure is due to a path failure between the disk array devices 20 and 30 ( Step S120).

  As a result of the determination in step S120, if the copy failure is due to a path failure, the processing at the time of the copy failure is terminated and waits until the path is recovered.

  On the other hand, if the copy failure is due to a factor other than the path failure, it is determined whether the copy process has been retried (step S121).

  If the result of the determination in step S121 is that the copy process has been retried, the copy permission / prohibition state stored in the concentrator 26 that manages the group is changed to a copy prohibition state (step S122).

  On the other hand, if the copy process has not been retried, a copy retry process is performed (step S123). When the above operation process is executed and the copy failure continues, the subsequent copy process operation is stopped, so that the logical disk at the remote site 2 can maintain the order guarantee state immediately before the copy failure. .

  By using the remote copy processing system between the disk array devices as described above, when there is a request for writing update data from the host computer 10 to the disk array device 20 at the main site 1, the order guarantee information regarding the requested update data ( Control information) is stored in a transmission buffer (transmission management buffer 26C) provided in the disk array device 20 every time update data is requested. On the other hand, the requested update data itself is not all stored in the transmission buffer (transmission data buffer 26D), but is the previous update data for which a write request has been received from the host 10, and the remote site. Only the update data that has not yet been copied to the second disk array device 30 and that overlaps the update data stored in the cache 22 is stored. Therefore, it is possible to reduce the memory of the buffer for storing the update data, and it is possible to realize the remote copy that ensures the order guarantee based on the control information.

  Compared to the semi-synchronous order-guaranteed copy method in which update data is stored in the buffer each time update data is requested, this method only copies (saves) duplicate update data to the buffer. The amount of data stored in the buffer can be suppressed, and the occurrence of performance degradation (for example, a buffer empty waiting state) due to overflow of stored data can be suppressed. Asynchronous order-guaranteed remote copy with a good response to the host can be realized by using a small number of buffers.

  Here, a part or all of the functions executed by each component of the remote copy processing system between the disk array devices according to the embodiment of the present invention is constructed as a program, and the program is executed by the computer. Good. In this case, the same effect as that described in the above embodiment can be obtained.

  About each embodiment mentioned above, if the summary of the novel technical content is put together, it will become as follows. A part or all of the above-described embodiment is as follows as a novel technique, but the present invention is not necessarily limited to this.

(Supplementary Note 1) A disk array device in which a disk array device at a main site and a disk array device at a remote site are connected via a remote line, and data stored in the disk array device at the main site is copied to the disk array device at the remote site A remote copy processing system between
The disk array device at the main site is
When there is an update data write request from the host computer, the order guarantee information, which is the update data write control information, is stored in synchronization with the update data storage processing in the cache provided in the disk array device. Management buffer for transmission,
When there is an update data write request from the host computer, the order guarantee information regarding the update data of the request and the order guarantee information regarding the update data of the previous request from the host computer stored in the transmission management buffer are Information duplication determination means for determining whether or not to overlap,
When the information duplication determination unit determines that the order guarantee information regarding the two update data is duplicated, the update data of the previous request stored in the cache is read and the read A data buffer for transmission in which update data is stored;
Update data stored in the transmission data buffer and update data stored in the cache are copied to the remote site disk array device asynchronously with the update data storage processing in the main site disk array device. A transmission copy control means;
A remote copy processing system between disk array devices.

(Supplementary Note 2) The order guarantee information related to the update data stored in the transmission management buffer is:
Order guarantee number information indicating the order of the updated data, update range information indicating the range of the updated data, copy destination disk array device name information indicating the copy destination of the data, and update data are the data buffer for transmission Data copy presence / absence information indicating whether or not the data has been copied to the transmission data buffer, and copy data storage destination information indicating the buffer number of the transmission data buffer in which the data is stored. The remote copy processing system between disk array devices according to appendix 1, wherein

(Supplementary Note 3) The information duplication determination unit stores that there is no data copy presence / absence information in the transmission data buffer among the order guarantee information regarding the update data of the previous request stored in the transmission management buffer. The remote copy processing system between disk array devices according to appendix 1 or 2, wherein the order guarantee information is subject to duplication determination.

(Additional remark 4) The said transmission copy control means copies to the disk array apparatus of the said remote site based on the data copy existence information to the transmission data buffer among the order guarantee information memorize | stored in the said transmission management buffer. 4. The remote copy processing system between disk array devices according to any one of appendices 1 to 3, wherein the copy source of each update data to be determined is discriminated.

(Supplementary Note 5) A disk array device in which a disk array device at a main site and a disk array device at a remote site are connected via a remote line, and data stored in the disk array device at the main site is copied to the disk array device at the remote site In the remote copy processing system between
When there is an update data write request from the host computer, the order guarantee information related to the update data of the request and the order guarantee related to the update data of the previous request stored in the transmission management buffer installed in the disk array device at the main site Whether the information is duplicated or not is determined by the information duplication determination means equipped in the disk array device,
When it is determined by the information duplication determination means that the order guarantee information regarding the two update data is duplicated, an I / O processing unit provided in the disk array device is provided in the disk array device. Storing the update data of the previous request from the host computer stored in the cache being stored in a transmission data buffer provided in the disk array device;
Subsequently, the I / O processing unit stores in the cache update data relating to the request for which update data has been requested from the host computer, and also transmits order guarantee information relating to the update data of the request to the transmission management Memorize it in the buffer,
The transmission copy control means installed in the disk array device at the main site sends the update data stored in the transmission data buffer and the update data stored in the cache to the disk array device at the remote site. A remote copy processing method between disk array devices, wherein copy processing is performed asynchronously with update data storage processing in the disk array device at the main site.

(Supplementary note 6) In the remote copy processing method between disk array devices according to supplementary note 5,
The order guarantee information related to the update data stored in the transmission management buffer includes order guarantee number information representing the order of the updated data, update range information representing the range of the updated data, and a data copy destination. The copy destination disk array device name information to be represented, the data copy presence / absence information to the transmission data buffer indicating whether or not the update data is the data copied to the transmission data buffer, and the data are stored Contains copy data storage location information that represents the buffer number of the data buffer for transmission,
In determining whether or not the order guarantee information related to the two update data is duplicated, the information duplication determination means includes the order guarantee information related to the update data of the previous request stored in the transmission management buffer. A method of remote copy processing between disk array devices, wherein duplication determination is made for the order guarantee information stored as having no data copy presence / absence information in the data buffer for transmission.

(Supplementary note 7) In the remote copy processing method between disk array devices according to supplementary note 6,
When asynchronously copying update data to the disk array device at the remote site, the transmission copy control means includes data copy presence / absence information to the transmission data buffer in the order guarantee information stored in the transmission management buffer. The remote copy processing method between disk array devices, wherein the copy source of each update data to be copied to the disk array device at the remote site is determined based on the above.

(Supplementary Note 8) A disk array device in which a disk array device at a main site and a disk array device at a remote site are connected via a remote line, and data stored in the disk array device at the main site is copied to the disk array device at the remote site In the remote copy processing system between
An update data storage processing function for storing the update data in a cache provided in the disk array device of the main site when there is a write request for update data from the host computer;
An order guarantee information storage processing function for storing the order guarantee information related to the update data in a transmission management buffer provided in the disk array device of the main site in synchronization with the update data storage process in the cache;
When there is an update data write request from the host computer, the order guarantee information related to the update data of the request and the order guarantee information related to the update data of the previous request from the host computer stored in the transmission management buffer are Information duplication judgment function for judging whether or not they overlap,
When it is determined by the information duplication determination function that the order guarantee information regarding the two update data is duplicated, the update data stored in the cache is read out, and the read update data is read out from the main site disk. Duplicate update data storage processing function for storing in the transmission data buffer provided in the array device,
Update data stored in the transmission data buffer and update data stored in the cache are copied to the remote site disk array device asynchronously with the update data storage processing in the main site disk array device. With remote copy function,
A program for remote copy processing between disk array devices, wherein each of these functions is realized by a computer.

(Supplementary note 9) In the remote copy processing program between the disk array devices according to supplementary note 8,
The order guarantee information related to the update data stored in the transmission management buffer includes order guarantee number information representing the order of the updated data, update range information representing the range of the updated data, and a data copy destination. The copy destination disk array device name information to be represented, the data copy presence / absence information to the transmission data buffer indicating whether or not the update data is the data copied to the transmission data buffer, and the data are stored Contains copy data storage location information that represents the buffer number of the data buffer for transmission,
The information duplication determination function is the order guarantee information stored as no data copy presence / absence information to the transmission data buffer among the order guarantee information regarding the update data of the previous request stored in the transmission management buffer. A program for remote copy processing between disk array devices, wherein the computer is made to realize this function.

(Supplementary note 10) In the remote copy processing program between the disk array devices according to supplementary note 9,
The remote copy function is based on the data copy presence / absence information to the transmission data buffer in the order guarantee information stored in the transmission management buffer. A program for remote copy processing between disk array devices, characterized in that a copy source is discriminated and this function is realized by the computer.

  For example, it can be used in the computer industry. Specifically, the present invention can be used in a manufacturing industry that manufactures storage devices.

1 Main site 2 Remote site 10, 15 Host (host computer)
20, 30 Disk array device 21, 31 I / O processing unit 22, 32 Cache 23, 24, 33, 34 Group 25 Group registration means 26, 27 Concentrator 26A Information duplication judgment means 26B Transmission copy control means 26C Transmission management buffer 26D Data buffer for transmission 40 Remote line (communication line)
51 Order guarantee number 52 Logical disk number 53 Update range 54 Copy destination disk array device 55 Copy destination logical disk number 56 Presence of data copy to buffer 57 Copy data storage destination

Claims (10)

Remote copy between disk array devices that connect the disk array device at the main site and the disk array device at the remote site via a remote line and copy the data stored in the disk array device at the main site to the disk array device at the remote site A processing system,
The disk array device at the main site is
When there is a request for writing update data from the host computer, at least the updated data of the update data write control information in synchronization with the storage process of the update data in the cache provided in the disk array device A transmission management buffer in which order guarantee information including update range information representing a range of
When there is an update data write request from the host computer, the update range information included in the order guarantee information regarding the update data of the request and the update data of the previous request from the host computer stored in the transmission management buffer Information duplication determination means for determining whether or not the update range information included in the order guarantee information regarding
When it is determined by the information duplication determination means that the update range information included in the order guarantee information regarding the two update data is duplicated, the update data of the previous request stored in the cache is read. A data buffer for transmission in which the read update data is stored;
Update data stored in the transmission data buffer and update data stored in the cache are copied to the remote site disk array device asynchronously with the update data storage processing in the main site disk array device. A transmission copy control means;
A remote copy processing system between disk array devices. The order guarantee information regarding the update data stored in the transmission management buffer is:
And order assurance ID information indicating the order of the updated data, and the destination disk array device name information indicating the destination of the data, whether the data updating data is copied into the transmit data buffer 2. The data copy presence / absence information to the transmission data buffer representing, and copy data storage destination information representing the buffer number of the transmission data buffer in which data is stored are included. Remote copy processing system between disk array devices.   The information duplication determination means is the order guarantee information stored as no data copy presence / absence information to the transmission data buffer among the order guarantee information regarding the update data of the previous request stored in the transmission management buffer. 3. The remote copy processing system between disk array devices according to claim 1, wherein the system is a target of duplication determination.   The transmission copy control means includes each update data to be copied to the disk array device at the remote site based on the data copy presence / absence information to the transmission data buffer among the order guarantee information stored in the transmission management buffer. The remote copy processing system between disk array devices according to any one of claims 1 to 3, wherein the copy source is discriminated from one another. Remote copy between disk array devices that connect the disk array device at the main site and the disk array device at the remote site via a remote line and copy the data stored in the disk array device at the main site to the disk array device at the remote site In the processing system,
When there is a write request for update data from the host computer, the update range information included in the order guarantee information related to the update data of the request and the previous request stored in the transmission management buffer provided in the disk array device at the main site Whether or not the update range information included in the order guarantee information related to the update data is duplicated is determined by the information duplication determination means equipped in the disk array device,
When it is determined by the information duplication determination means that the update range information included in the order guarantee information related to the two update data is duplicated, the I / O processing unit equipped in the disk array device performs the disk Storing the update data of the previous request from the host computer stored in the cache provided in the array device in a transmission data buffer provided in the disk array device;
Subsequently, the I / O processing unit stores in the cache update data relating to the request for which update data has been requested from the host computer, and also transmits order guarantee information relating to the update data of the request to the transmission management Memorize it in the buffer,
The transmission copy control means installed in the disk array device at the main site sends the update data stored in the transmission data buffer and the update data stored in the cache to the disk array device at the remote site. A remote copy processing method between disk array devices, wherein copy processing is performed asynchronously with update data storage processing in the disk array device at the main site. The remote copy processing method between disk array devices according to claim 5,
Order assurance information on update data stored in the transmission management buffer, the order assurance ID information indicating the order of the updated data, and the destination disk array device name information indicating the destination of the data, updating Data copy presence / absence information to the transmission data buffer indicating whether the data is copied to the transmission data buffer, and copy data indicating the buffer number of the transmission data buffer in which the data is stored Contains storage location information,
In determining whether or not the order guarantee information related to the two update data is duplicated, the information duplication determination means includes the order guarantee information related to the update data of the previous request stored in the transmission management buffer. A method of remote copy processing between disk array devices, wherein duplication determination is made for the order guarantee information stored as having no data copy presence / absence information in the data buffer for transmission. The remote copy processing method between disk array devices according to claim 6,
When asynchronously copying update data to the disk array device at the remote site, the transmission copy control means includes data copy presence / absence information to the transmission data buffer in the order guarantee information stored in the transmission management buffer. The remote copy processing method between disk array devices, wherein the copy source of each update data to be copied to the disk array device at the remote site is determined based on the above. Remote copy between disk array devices that connect the disk array device at the main site and the disk array device at the remote site via a remote line and copy the data stored in the disk array device at the main site to the disk array device at the remote site In the processing system,
An update data storage processing function for storing the update data in a cache provided in the disk array device of the main site when there is a write request for update data from the host computer;
Order guarantee information storage processing for storing order guarantee information including update range information related to the update data in a transmission management buffer provided in the disk array device of the main site in synchronization with the update data storage processing to the cache function,
When there is an update data write request from the host computer, the update range information included in the order guarantee information related to the update data of the request, and the update data of the previous request from the host computer stored in the transmission management buffer Information duplication judgment function for judging whether or not the update range information included in the order guarantee information related to
When it is determined by the information duplication determination function that the update range information included in the order guarantee information regarding the two update data is duplicated, the update data stored in the cache is read and the read update A duplicate update data storage processing function for storing data in a transmission data buffer provided in the disk array device of the main site;
Update data stored in the transmission data buffer and update data stored in the cache are copied to the remote site disk array device asynchronously with the update data storage processing in the main site disk array device. With remote copy function,
A program for remote copy processing between disk array devices, wherein each of these functions is realized by a computer. The remote copy processing program between disk array devices according to claim 8,
Order assurance information on update data stored in the transmission management buffer, the order assurance ID information indicating the order of the updated data, and the destination disk array device name information indicating the destination of the data, updating Data copy presence / absence information to the transmission data buffer indicating whether the data is copied to the transmission data buffer, and copy data indicating the buffer number of the transmission data buffer in which the data is stored Contains storage location information,
The information duplication determination function is the order guarantee information stored as no data copy presence / absence information to the transmission data buffer among the order guarantee information regarding the update data of the previous request stored in the transmission management buffer. A program for remote copy processing between disk array devices, wherein the computer is made to realize this function. The remote copy processing program between disk array devices according to claim 9,
The remote copy function is based on the data copy presence / absence information to the transmission data buffer in the order guarantee information stored in the transmission management buffer. A program for remote copy processing between disk array devices, characterized in that a copy source is discriminated and this function is realized by the computer.

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