JP2003085017A - Data assurance system - Google Patents

Abstract

(57) [Summary] In remote copy processing, data transfer between a central processing unit and a master disk controller and between a master disk controller and a remote disk controller are performed in parallel, and the central processing unit The purpose of the present invention is to realize reception from a remote disk controller and transmission to a remote disk controller on the same port. Utilizing bidirectional data transfer and multiplex processing, which are characteristics of Fiber Channel, and using a header conversion circuit composed of a header conversion buffer and a header conversion control unit, a frame received from a central processing unit is mastered. The problem is solved by temporarily storing the data in a header conversion buffer in the side disk device, converting the header portion of the frame for transmission to the remote side disk device, and transmitting the converted data. The data transfer between the central processing unit and the master disk device and between the master disk device and the remote disk device can be performed in parallel, thereby improving the processing performance. Also, reception from the central processing unit and transmission to the remote disk device can be realized by the same port.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a central processing unit (hereinafter referred to as CPU) such as a mainframe or an open system server and a master disk control unit (hereinafter referred to as MCU).
And a remote disk control unit (hereinafter referred to as RCU) configuration, the present invention relates to a synchronous remote copy processing system connected by using a fiber channel,
The present invention relates to a data guarantee system intended to perform remote copy processing between U and RCU at high speed and with a single port.

[0002]

2. Description of the Related Art MCU (master disk controller) and R
A CU (remote disk controller) is a controller of a disk subsystem, to which disk drives are connected.

The MCU controls the I / O operation from the host processor to the disk drive on the master side and the copy operation between the disk drive on the master side and the disk drive on the remote side. In addition, the MCU provides the function of managing the status and configuration of remote copy.

The RCU performs the write operation indicated by the MCU. As a conventional technique for performing the synchronous remote copy, the CPU, the MCU, and the RCU are connected between the ESCON (Ente
rprise System Connection) protocol (known example Enter
priseSystems Architecture / 390 ESCON I / O Interfac
Peer-to-Peer in the configuration connected by e)
There is Remote Copy (known example IBM Enterprise
Storage Server Peer-toPeer Remote Copy, a function to maintain consistency by placing duplicates of the same data on multiple Enterprise Storage Servers).

The information processing system comprises a plurality of channel devices and one or a plurality of input / output devices connected to the channels. A channel uses a channel command word (CCW: Channel Command Word) containing a command code, count, and data address for the input / output device.
I / O operations to be performed are specified. The CCW is first prepared in the main memory of the CPU by a program. C
The CW has a command chain flag, and the channel executes the CCW having this flag set to "1" and then executes the next CCW continuously. This operation is called a command chain.

Generally, in the case of the synchronous remote copy process using the ESCON protocol, since it is a protocol for transmitting a status indicating whether the command is normally completed for each command chain between the CPU and the MCU, the MCU is called. When the write data on the side is confirmed, RCU
To transfer data to.

For example, when writing two records, DX (Define Extext) / LOC (LOCate reco
rd) / WRUPD (Write Update Data) / WRUPD
CCW chain of (using known example IBM 3990/9390 Sto
rage Control Reference). "DEFINE EXTENT", "LOC
ATE RECORD "(The number of records to be processed and the data length are given by the LOCATE RECORD command) These are disk control commands that specify the alignment of the disk head on the device specified by the channel, and" Write Update Data
a ”directs the updating of data there. FIG. 2 shows the operation sequence between the CPU and the MCU when the CCW chain is issued, and the data transfer timing and operation sequence from the MCU to the RCU side.

First, the first command D from the CPU
An X command frame (DX CMD) is transmitted to the MCU (201). Upon receiving this, the MCU receives a command response frame (CM
(R) is transmitted to the CPU (202).

In response to this, the CPU sends a command response reception frame (ACPT CMR) indicating reception of the command response to the MCU (203). C
Following this, the PU follows the DX command data frame (DX
(DATA) is transmitted to the MCU (204). MCU
In response to this, the DX command process is executed, and if the DX command ends normally, a status frame (STS'0C ') indicating that the DX command has ended normally is transmitted to the CPU (20
5).

In response to this, the CPU receives the command chain of the LOC command frame (LOC CM
(D) is transmitted to the MCU (206). Upon receiving this, the MCU sends a command response (CMR) indicating that it has received the LOC command to the CPU (20
7).

In response to this, the CPU transmits a data frame (LOC DATA) of the LOC command to the MCU (208). Upon receiving this, the MCU executes the processing of the LOC command, and if it is completed normally, the status frame (STS'0C ') indicating that the LOC command is completed normally.
Is transmitted to the CPU (209).

In response to this, the CPU commands the LOC command to chain the WRU for writing record 1.
A PD command frame (WRUPD # 1 CMD) is transmitted to the MCU (210). In response to this, the MCU transmits a command response frame (CMR) indicating that the WRUPD command of record 1 has been received (211).

Upon receipt of this, the CPU receives the WRU of record 1.
A PD data frame (WRUPD # 1 DATA) is transmitted to the MCU (212). The MCU sends a command frame (WR CMD) indicating that writing is started from the record 1 of the track of the disk drive to the RCU at the timing of receiving this (251).

The MCU is the W of record 1 in the MCU.
When the processing of the RUPD command is executed and the processing ends normally, a status frame (STS'0C ') indicating that the WRUPD of record 1 has ended normally is transmitted to the CPU (213).

In response to this, the CPU receives the WRU of record 1
WRUPD command frame (WRUPD # 2 CM) for writing record 2 command chaining to PD command
(D) is transmitted to the MCU (214). In response to this, the MCU sends a command response frame (CMR) indicating that it has received the WRUPD command of record 2 to the CPU.
To (215).

Upon receipt of this, the CPU receives the WRU of record 2.
A PD data frame (WRUPD # 2 DATA) is transmitted to the MCU (216). On the other hand, the RCU receives the command frame indicating that there is a write from the record 1 and transmits a command response frame (CMR) indicating that the command frame has been received to the MCU (25
2).

In response to this, the MCU checks whether or not the last data of the CCW chain or the last data of the track (all data frames of record 2 in this figure) has been received. All the data frames are in a waiting state, and if they have been received, data is transmitted to the RCU according to the requested amount of write data (WR DATA) of record 1 and record 2 (253).

The MCU receives the data frame of the WRUPD of the record 2 and receives the WRUPD of the record 2 in the MCU.
If command processing is executed and the processing ends normally, the status frame (STS'08 ') indicating the channel end is sent to the CPU in order to temporarily disconnect the connection between the CPU and MCU until data writing to the RCU is completed. To (217).

In response to this, the CPU transmits a status reception frame (STS ACPT) indicating that the last status of the CCW chain has been received to the MCU (21
8). Upon receiving this, the MCU transmits a device level acknowledge frame indicating that the status reception frame has been received to the CPU (219).

On the other hand, the RCU receives the data frames of the record 1 and the record 2 and executes the write processing in the RCU. If the RCU completes normally, a status frame (STS'0C ') indicating the normal completion is sent to the MCU. (254). In response to this, the MCU receives the status, and receives the status. Status reception frame (STS ACPT)
To the RCU (255).

In response to this, the RCU transmits a device level acknowledge frame (DEVACK) indicating that the status reception frame has been received to the MCU (25
6) The writing process to the remote side is completed.

Further, the MCU receives the normal end status from the RCU, judges that the write processing to the remote side is completed, and at this occasion, the MCU re-executes to report the device end status. A request connection frame (REQ CON) which is a connection request is transmitted (220).

In response to this, the CPU transmits a connection reception frame indicating that the reconnection request has been received to the MCU (221). Upon receiving this, the MCU recognizes that the reconnection has been accepted, and transmits a status frame (STS'04 ') indicating the device end to the CPU (222).

In response to this, the CPU transmits a status reception frame indicating that the status of the device end has been received to the MCU (223). In response to this, the MCU sends a device level acknowledge frame (DEVACK) indicating that it has received the status reception frame to the CPU.
(224), and the writing process from the CPU is completed.

As described above, in the general remote copy processing in the ESCON protocol, the CPU to the MCU
The CPU-MCU is a processing method that starts data transfer from the MCU to the RCU when the data transfer to the end of the CCW chain to the end of the track is completed.
The data transfer between the MCU and the MCU-RCU is not performed in parallel, which affects the performance.

Next, the fiber channel technology will be described. The foundation of Fiber Channel is the AN
SI's FC-PH (Fibre Channel PHysical and signa)
lling). By conforming to FC-PH, a higher-level protocol using Fiber Channel can operate a plurality of higher-level protocols on a common Fiber Channel. In FC-PH, bidirectional simultaneous data transfer, which is a characteristic of Fiber Channel, is defined, which allows data to be transmitted and received in parallel.

The concept of exchange is defined in FC-PH. A series of transmission / reception sequences of command frames and data frames exchanged with the disk control device for one input / output command issued by the CPU to the disk subsystem is called exchange. By using this exchange, multiple processing is possible.

In FC-PH, a general fiber channel frame structure is defined. Frame is
SOF (Start_of_Frame), Frame Header, DataField, CRC
(Cyclic Redundancy Check character), EOF (End_of
_Frame), of which the Frame Header includes D_ID (Destination_ID) indicating the destination address and S_ID (Source_ID) indicating the source address. Common D_ID, S defined in this FC-PH
The transmission direction is determined by _ID.

[0029]

SUMMARY OF THE INVENTION An object of the present invention is to perform remote copy processing between CPU-MCU and MCU-RCU.
The data transfer between them is performed in parallel, and the reception from the CPU and the transmission to the RCU are realized by the same port.

[0030]

The data guarantee system of the present invention is a remote copy process using the fiber channel protocol, and utilizes the bidirectional data transfer and multiplex processes which are the features of the fiber channel protocol to convert the header. By using a header conversion circuit composed of a buffer and a header conversion control unit, a frame received from a CPU is temporarily stored in a header conversion buffer in the MCU, and the header part of the frame is converted for RCU transmission and transmitted. To solve.

[0031]

BEST MODE FOR CARRYING OUT THE INVENTION A data guarantee system in a fiber channel according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of a remote copy system using the fiber channel protocol which is an embodiment of the present invention. The configuration of this embodiment is roughly the CPU (101) which is a central processing unit, the MCU (102) which is a master side disk control unit, the DKU (103) which is a master side disk drive unit, and the remote side disk. RCU (104) which is a control unit, DKU (105) which is a disk drive unit on the remote side, and CPU-
A director device (106) for switching the connection between the MCU and the RCU, a fiber cable (107) for connecting the CPU and the director device, and a fiber cable (108) for connecting the director device and the MCU.
It is composed of a fiber cable (109) connecting the director device and the RCU.

The central processing unit may be a mainframe or an open type server. In addition, as a connection configuration, a CPU is used without interposing a director device.
A configuration in which -MCU and MCU-RCU are directly connected by a fiber cable may be used.

Further, there are a plurality of RCUs, which are MC
A configuration in which the director device is connected to multiple RCUs with a single fiber cable between the U-directors, or an MCU
It is also possible to directly connect to a plurality of RCUs.

Further, there are a plurality of CPUs, which are MC
Between the U-directors, a single fiber cable may be used to connect the director device to a plurality of CPUs, or the MCU may be directly connected to a plurality of CPUs. The internal structure of the MCU on which the present invention is based includes a receive buffer (111) for receiving a frame from a CPU or RCU,
A transmission buffer (112) for transmitting a frame to the CPU or RCU, and a header for converting a frame received from the CPU into a header and transferring it to the RCU, or a header for converting a frame received from the RCU into a header and transferring to the CPU. An internal buffer (114) including a conversion buffer (113) and a header conversion buffer, which is a temporary data storage area for transferring a frame received from the CPU to the CACHE (115) in the MCU, high-speed processing, etc. CACHE (11 that stores some drive information for the purpose of
5), a fiber protocol control unit (116) that controls header conversion processing for RCU transmission, and a channel adapter control unit (117) that controls data processing between the internal buffer (114) and CACHE (115). , CA
It is composed of a disk adapter controller (118) that controls data processing between the CHE (115) and the disk drive.

For example, a FIC which is a mainframe fiber channel for connecting between the CPU, the MCU and the RCU
ON (Fibre Channel Connection) is an FC-SB-2 (FIBRE CHANNEL SINGLE-BYT) standardized by ANSI.
E COMMAND CODE SET-2 MAPPING PROTOCOL) is the base. As a feature of this FICON, since the fiber channel protocol is used, transmission / reception can be performed bidirectionally, and a unit called exchange can be processed in multiple.

That is, CPU to MC on a single cable
While receiving CCW chain data for write processing to U,
It is possible to transmit CCW chain data for write processing from MCU to RCU. In addition, FICON also has a feature of transmitting a command chain in a pipeline, which allows commands to be issued continuously in a pipeline without receiving the status of normal completion for each command in the CCW chain. . With this configuration, the CPU
Store the frame issued from the
If the CON protocol control unit performs frame analysis processing and, as a result, a frame that needs to be transferred to the RCU on the remote side, transfers it to the internal buffer, performs header conversion processing, and transfers it to the transmission buffer to the RCU. It becomes possible to perform parallel processing.

FIGS. 3 and 4 are diagrams showing the overall processing flow from the reception of the frame. First, when a frame is received, it is determined whether the frame is a frame received from the CPU or RCU (301). If the frame is received from the CPU or RCU, frame information, command information, and parameter information are fetched from the reception buffer (302).

Next, it is determined whether the received frame is received from the CPU (303). If it is a frame received from the CPU, it is determined whether the remote copy target CCW chain information is confirmed or unconfirmed (304).

If the remote copy target CCW chain information is uncertain, it is determined whether the remote copy non-target CCW chain information is definite or uncertain (305). If the remote copy non-target CCW chain information is uncertain, the remote copy necessity analysis processing is performed using the command information and the parameter information (306). This analysis process will be described in detail with reference to FIG.

Next, it is judged from the analysis result of 306 whether the remote copy required information is set to required (30
7). If the remote copy required information is uncertain, it is determined whether the remote copy unnecessary information is set to be unnecessary (308). If the remote copy unnecessary information is uncertain, the received frame is transferred to the internal buffer and stored until the necessity of remote copy is determined by the subsequent command frame analysis processing (309).

Next, the processing of the frame in the MCU is executed (310) and the processing returns to the frame receiving processing. If 30
If the remote copy unnecessary information is set to be unnecessary in the determination process of No. 8, since the remote copy process is unnecessary, the frame accumulated in the internal buffer until now is released (311).

Next, information indicating that the CCW chain is a remote copy non-target CCW chain is set (312). Next, the process of the frame in the MCU is executed (313), and the process returns to the frame receiving process. if,
If the remote copy required information is set to necessary in the determination processing of 307, the remote copy processing is necessary, so the frame information is first transferred to the internal buffer (321).

Next, the header conversion process is executed together with the frames accumulated so far in the internal buffer (32
2). Details of the header information that is the target of this header conversion will be described with reference to FIG. Next, the frame with the converted header is transferred to the transmission buffer and transmitted to the RCU (32
3). Next, information indicating that the CCW chain is a remote copy target CCW chain is set (32
4).

Next, the processing of the frame in the MCU is executed (325), and the processing returns to the frame reception processing. If 3
If the remote copy non-target CCW chain information is confirmed in the determination processing of 05, since the remote copy processing is not necessary, the processing proceeds to 311 and thereafter. If 3
If the remote copy target CCW chain information is confirmed in the determination processing of 04, since remote copying is necessary, the processing proceeds to 321 and thereafter. If it is a received frame from the MCU in the determination processing of 303, the MCU
It is determined whether the processing corresponding to the received frame on the side has been completed (331). If the processing is completed, CP
Since it is necessary to transmit a frame to U, the frame information is first transferred to the internal buffer (332). next,
A header conversion process is executed (333).

Next, the header-converted frame is transferred to the transmission buffer and transmitted to the CPU (334), and the process returns to the frame reception process. If the processing corresponding to the received frame on the MCU side is not completed in the determination processing of 331, information indicating that the processing on the frame is completed by the RCU is set (341), and the frame reception processing is performed. Return to.
If the frame is inside the MCU in the judgment processing of 301, it is judged whether the processing corresponding to the received internal frame on the RCU side is completed (351).

If the processing is completed, a transmission frame is generated in the transmission buffer and transmitted to the CPU (35
2) Return to the frame receiving process. If the processing corresponding to the received internal frame on the RCU side has not been completed in the determination processing of 351, information indicating that the frame has been processed by the MCU is set (361), and frame reception is performed. Return to processing.

FIG. 5 is a diagram showing a flow for analyzing the necessity of remote copy from the command information and the parameter information in the received frame. First, command information and parameter information are fetched (401). Then the command is R
It is determined whether the command has a possibility of EAD (read processing) or WRITE (write processing) (402).
If the command can be READ or WRITE, it is determined whether it is a READ or WRITE system control command (403).

If the command is a READ or WRITE type control command, parameter information and M
From the remote copy target area information managed by the CU,
The CCW chain concerned is WR to the remote copy target range
It is determined whether it is an ITE access (404).

If the WRI to the remote copy target range
If the TE access cannot be determined, the command chain condition is determined from the command information (40
5). If the command chain is not performed, it means that the CCW chain is not a remote copy target, so remote copy unnecessary information is set (406), and the process proceeds to the next process. If a command chain is made in the determination processing of 405, the necessity of remote copy is uncertain, so the remote copy information remains uncertain, and the next processing is performed. if,
In the determination processing of 404, WR to the remote copy target range
If it is ITE access, since remote copy is required, remote copy required information is set (41
1), move to the next processing.

If it is the READ or WRITE command itself in the judgment processing of 403, the WRI
It is determined whether it is a TE command or a READ command (421). If it is a READ command, the command chain condition is judged from the command information (422).

If the command chain is not performed, it means that the CCW chain is not a remote copy target, so remote copy unnecessary information is set (423), and the process proceeds to the next process. If a command chain is made in the determination processing of 422, the necessity of remote copy is uncertain, so
The remote copy information remains uncertain, and the next processing is performed.
If it is a WRITE command in the determination processing of 421, it is determined from the remote copy target area information managed by the MCU whether the access is to the remote copy target range (431).

If the remote copy target range is to be accessed, remote copy is necessary. Therefore, remote copy required information is set (432), and the process proceeds to the next step.
If it is determined in step 431 that the remote copy target range is not accessed, remote copy is not necessary, so remote copy unnecessary information is set (441), and the process proceeds to the next process.

If there is a command that does not have the possibility of READ or WRITE in the judgment processing of 402, remote copy is unnecessary, so remote copy unnecessary information is set (451) and the process proceeds to the next processing.

FIG. 6 is a diagram showing a FICON device level frame format and information to be converted in the header conversion process. The FICON device level frame consists of 4 bytes of Start of Frame (SOF) and FC-PH Frame.
Header 24 bytes (501), FC-SB-2 Header 8 bytes (502), IU Header 8 bytes, DIB Header
12 bytes, FC-SB-2 LRC 4 bytes, DIB Data 0
From 2016 bytes, FC-PH LRC 4 bytes, End of
Frame (EOF) It consists of 4 bytes.

However, in the hierarchy of FC-SB-2, 819
Since data is handled in units of 2-byte information unit (hereinafter referred to as IU), if the total IU from FC-SB-2 Header to DIB Data exceeds 2048 bytes, Start of Frame (SOF) 4 Byte and FC-PH Fram
e Header 24 bytes (501) and DIB Data 0 to 2
048 bytes, FC-PH LRC 4 bytes, End of Frame
(EOF) A frame consisting of 4 bytes.

Of these, 501 FC-PH Frame Header
Is R_CTL Field 1 byte, D_ID Field 3 bytes (511), CS_CTL Field 1 byte, S_ID Field
3 bytes (512), TYPE Field 1 byte, F_CTL
Field 3 bytes, SEQ_ID Field 1 byte, DF_CTL
Field 1 byte, SEQ_CNT Field 2 bytes, OX_ID
Field 2 bytes (513), RX_ID 2 bytes, Par
ameter Field It consists of 4 bytes. Also, 502
FC-SB-2 Header is Reserved 1 byte and Channel I
mage ID 1 byte (521) and Reserved 1 byte,
Control-Unit ImageID 1 byte (522) and Device
It consists of Address 2 bytes (523) and Reserved 2 bytes.

In the header conversion processing for transmitting the frame received from the CPU to the RCU, the transmission destination of the frame is first determined based on the pair information of the pair volume created by remote copy managed in the MCU. Indicates D_ID
(511) is converted from the MCU D_ID to the RCU D_ID. Also, the S_ID (512) indicating the transmission source of the frame is set to C
Convert S_ID of PU to S_ID of MCU. CCW
OX_ID (513) indicating the chain exchange is C
Convert OX_ID managed by PU to OX_ID managed by MCU. Also, the CH Image ID (521) of the logical path to be processed in the CCW chain is converted from the CH Image ID of the logical path between the CPU and MCU to the CH Image ID of the logical path between the MCU and RCU.

Further, the CU Image ID (522) of the logical path to be processed by the CCW chain is converted from the CU Image ID of the logical path between the CPU and MCU to the CU Image ID of the logical path between the MCU and RCU. Also, the Device Address (523) that is the processing target of the CCW chain is set to the MCU De
vice address to remote copy pair of RCU
Convert to Device Address.

On the other hand, the frame received from the RCU is CP
In the header conversion process for transmitting to the U, first, the D_ID (511) indicating the destination of the frame is converted from the D_ID of the MCU to the D_ID of the CPU based on the remote copy pair information managed in the MCU. . Also, the S_ID (512) indicating the transmission source of the frame is converted from the S_ID of the RCU to the S_ID of the MCU.

Further, the OX_ID (513) indicating the exchange of the CCW chain is converted from the OX_ID managed by the RCU to the OX_ID managed by the MCU. Also, CH Image ID (52 of the logical path to be processed in the CCW chain)
1) is converted from CH Image ID of the logical path between MCU and RCU to CH Image ID of the logical path between CPU and MCU. In addition, the logical path to be processed in the CCW chain
The CU Image ID (522) is the CU Image ID of the logical path between the MCU and the RCU and the CUIma of the logical path between the CPU and the MCU.
Convert to ge ID. Also, the Device Address (523) that is the processing target of the CCW chain is set as the Device Addre of the RCU.
Device Add of MCU that becomes a remote copy pair from ss
Convert to ress.

FIG. 7 shows a CPU and MC when the present invention is applied.
It is a figure which shows the operation sequence between U, the data transfer timing from MCU to the RCU side, and an operation sequence.
First, a CPU sends a DX (Define Extext) command and a CMD + DATA frame (DX CMD + DATA) including a DX parameter to the MCU (60).
1). The MCU receives this and analyzes the frame. From the parameter of the DX command, it is uncertain whether the CCW chain concerned is the target of remote copy, so RC
Accumulate in internal buffer without sending to U.

Following this, the CPU continues to the LOC (LOCate rec
ord) command and CMD + DAT including parameters
The A frame (LOC CMD + DATA) is transmitted to the MCU (602). The MCU receives this and analyzes the frame. The parameter of the LOC command includes information capable of determining whether the CCW chain is a remote copy target.

If it is determined that the remote copy is required, the DX which has been received first and is being accumulated in the internal buffer.
The header conversion process of CMD + DATA is performed and it is transmitted to the RCU (651). In addition, following this, LOC C
MD + DATA header conversion processing is performed and transmission is performed to the RCU (652).

The CPU continues to 602 and then WR of record 1
UPD (Write Update Data) command and CMD + DATA frame (WRUPD # 1) including data of record 1
(CMD + DATA) is transmitted to the MCU (603). MC
In response to this, since the CCW chain has already been targeted for remote copy, U performs WRUPD # 1 CMD + DATA header conversion processing and sends it to the RCU (65
3).

The CPU follows 603 and then the WR of record 2
CMD including UPD command and record 2 data
A + DATA frame (WRUPD # 2 CMD + DATA) is transmitted to the MCU (604). In response to this, the MCU has already targeted the CCW chain for remote copy, so WRUPD # 2 CMD + DATA is converted to the header and R
It is transmitted to the CU (654).

The RCU receives the DX CMD + DATA of 651,
A command response frame (CMR) indicating that a DX command has been received is transmitted to the MCU (65
5). Upon receipt of this, the MCU receives the DX command, and if the reception processing of the DX command has been completed, it performs the CMR header conversion processing and sends it to the CPU (605).

RCU follows 655, followed by LOC CMD + DATA,
WRUPD # 1 CMD + DATA, WRUPD # 2 CMD + DATA processing is executed,
WRUPD # 2 When CMD + DATA processing ends normally, WRUP
A status frame (STS'0C ') indicating that D # 2CMD + DATA has ended normally is transmitted to the MCU (656).
Upon receiving this, the MCU receives the W of record 2 inside the MCU.
If processing of the RUPD command is completed normally, ST
Header conversion processing of S'0C 'is performed and transmitted to the CPU (606). In response to this, the CPU transmits a status reception frame (STS ACPT) indicating that the status of normal termination has been received to the MCU (607).

In response to this, the MCU performs STS ACPT header conversion processing and sends it to the RCU (657), and C
The processing of the CW chain is completed. As described above, it is understood that the data transfer can be performed in parallel as described above, and the processing performance is obviously improved by comparing the prior art example (FIG. 2) showing the data transfer timing and the operation sequence with FIG. 7.

[0070]

The data guarantee system of the present invention is based on the FIC.
It is a remote copy process using the ON protocol, and C
The frame received from the PU is temporarily stored in an internal buffer in the MCU, the header part of the frame is converted for RCU transmission, and the frame is transmitted to the CPU-MCU and MCU-R.
Data transfer between CUs can be performed in parallel, improving processing performance. Further, the reception from the CPU and the transmission to the RCU can be realized by the same port.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a remote copy system using a fiber protocol.

FIG. 2 CPU and MCU on ESCON protocol
FIG. 6 is a diagram showing an operation sequence between the two, data transfer timing from the MCU to the RCU side, and an operation sequence.

FIG. 3 is a diagram showing an overall processing flow from reception of a frame.

FIG. 4 is a diagram showing an overall processing flow from reception of a frame.

FIG. 5 is a diagram showing a flow of analyzing the necessity of remote copy from command information and parameter information in a received frame.

FIG. 6 is a diagram showing a device level frame format and information to be converted in a header conversion process.

FIG. 7 is a diagram showing an operation sequence between a CPU and an MCU, a data transfer timing from the MCU to the RCU side, and an operation sequence when the present invention is applied.

[Explanation of symbols]

101 ... Central processing unit 102 ... Master side disk control device 103 ... Master side disk drive device 104 ... Remote side disk control device 105 ... Remote side disk drive device 106 ... Director Device 107 ... Fiber cable 108 connecting CPU and director device 108 ... Fiber cable connecting director device and MCU 109 ... Fiber cable 111 connecting director device and RCU ... Reception buffer 112 ... .. Transmission buffer 113 ... Internal buffer 114 ... CACHE 115 ... Fiber protocol control unit 116 ... Channel adapter control unit 117 ... Disk adapter control unit

Continued front page    (72) Inventor Masami Maeda             Stock No.2 322 Nakazato, Odawara City, Kanagawa Prefecture             Hitachi, Ltd. RAID System Division (72) Inventor Dai Tsukada             Stock No.2 322 Nakazato, Odawara City, Kanagawa Prefecture             Hitachi, Ltd. RAID System Division F term (reference) 5B018 GA04 HA03 HA04 KA03 MA12                       QA15                 5B065 BA01 CA07 CC08 CE01 CH13                       EA33 ZA01                 5B082 DE05 DE07

Claims (7)

[Claims] 1. Data comprising a central processing unit and a master side disk unit connected by a fiber cable, the master side disk unit and a remote side disk unit connected by the fiber cable, and the master side disk unit having a header conversion circuit. A guarantee system, wherein a frame of a writing process issued from the central processing unit to the master side disk unit is processed in the master side disk unit,
In parallel with the processing, the frame is converted for transmission to the remote side disk device by using the header conversion circuit, the converted frame is issued from the master side disk device to the remote side disk device, and A data guarantee system characterized in that a writing process from a central processing unit to the master side disk device and a writing process to the remote side disk device are performed in parallel. 2. The data guarantee system according to claim 1, comprising a header conversion buffer for temporarily storing the frame of the writing process received from the central processing unit, and a header conversion control unit for converting the header part of the frame. A header conversion circuit for converting the frame for transmission to the remote side disk device, issuing the converted frame from the master side disk device to the remote side disk device, and the central processing unit to the master side. A data assurance system characterized in that a writing process to a disk device and a writing process to the remote side disk device are performed in parallel. 3. The data assurance system according to claim 1, wherein the frame of the write processing issued from the central processing unit to the master side disk unit by using a fiber channel protocol is stored in the master side disk unit. Processing, and in parallel with the processing, the header conversion circuit is used to convert the frame for transmission to the remote disk device, and the converted frame is transferred from the master disk device using the fiber channel protocol. A data guarantee system, which is issued to the remote side disk device, and performs a writing process from the central processing unit to the master side disk device and a writing process to the remote side disk device in parallel. 4. A data guarantee system according to claim 1, 2, or 3, wherein bidirectional data transfer and multiple processing between said central processing unit, said master side disk unit and said remote side disk unit. For processing the frame of the write processing issued from the central processing unit to the master side disk unit in the master side disk unit and performing the header conversion in parallel with the processing. A circuit is used to convert the frame for transmission to the remote side disk device, the converted frame is issued from the master side disk device to the remote side disk device, and the central processing unit to the master side disk device. Data writing process and the remote side disk device writing process are performed in parallel. Guarantee system. 5. The data guarantee system according to claim 1, 2, 3 or 4, wherein one or a plurality of said central processing units and said master side disk unit, and said master side disk unit. And a director device interposed between one or a plurality of the remote disk devices, and the director device and the master disk device are connected by the same physical cable. 6. A data guarantee system according to claim 1, 2, 3 or 4, wherein a plurality of said central processing units are connected to said master side disk unit. 7. The data assurance system according to claim 1, 2, 3, or 4, wherein the master side disk device is connected to a plurality of the remote disk devices.