JPH0465750A - Input/output control system - Google Patents

Abstract

PURPOSE:To quickly issue interface reset when there is no substitutive channel equipment by providing a channel control device with a status informing means for informing whether the device itself is operatable or not to the other channel control device. CONSTITUTION:In the channel control device 10 e.g., whether a fault is generated in the self-device or not is decided by a processor control part 14, and when the fault is generated, an operation status informing signal CHKSTP0 = 1 is outputted to the other channel control device 11. If the other device 11 is failed at the time of generating a fault in the self-device 10, signals CHKSTP0 = 1, CHKSTP1 = 1 are inputted to an AND circuit 17 in an exclusive information reset issuing means 15 and a signal RESETRQ = 1 specifying interface reset is outputted from the circuit 17. When plural channel control devices are successively disabled by faults, the exclusiveness of an I/O device is automatically reset.

Description

[Detailed Description of the Invention] [Summary] Regarding the input/output control method of channel control devices, a plurality of computer systems each have a plurality of unique channel control devices, with the aim of quickly issuing an interface reset in the event of a failure. In a system having channel devices and input/output devices connected via an input/output control device, a plurality of channel control devices sends an operation signal indicating whether the channel control device is operable or not. An operation state notification means that sends each other to other devices, and when a channel control device fails, the operation signal received from each other channel control device controlled by the same computer system is used to notify one of the other channel control devices. If none of the channel control devices can be used, it sends exclusive release information that causes the channel devices under the own device to release exclusive rights to the connected input/output devices. It has a proprietary information release issuing means as a configuration.

[Industrial Application Field] The present invention relates to an input/output control method in a computer system when a channel control device becomes inoperable due to a failure.

In the case of a system that integrates and operates a plurality of computer systems each having its own channel control device and channel device, the input/output device is configured to be shared by the plurality of computer systems.

In such a system, multiple channel control devices with the same function are configured in the same computer system, and if a failure occurs in one channel control device, processing can be performed by another device in the same computer system. By configuring it so that it continues, we aim to increase confidence.

However, if alternative processing cannot be performed by other channel control devices within the same system, the computer system configures the entire system so that the exclusive input/output devices are immediately released to other systems. There is a need.

In a multi-system where a plurality of computer systems share an input/output device, if a channel device or channel control device fails, it can be replaced by another similar device within the same computer system. This provides an input/output control method that continues processing and immediately releases the input/output device to another computer system if there is no alternative device.

[Conventional technology]

The conventional input/output control system will be explained with reference to FIG.

In the figure, 50 is a computer system A, 151 is a computer system B, 52.53 is a channel control device in the computer system A, 54.55 is a channel control device in the computer system B, 56.57 is a computer system A, and a channel control device in the computer system B, respectively. The input/output control device of system B, 58 and 59 are input/output devices such as magnetic disks, computer system A, computer system B, respectively.
CHI to CH17 are channel devices shared through human output control devices 56 and 57, and CH2
- CH2 is controlled by the channel control device 52, CH5 to CH8 are controlled by the channel control device 53, and CHI0 to CH13 are controlled by the channel control device 54.
CH14 to CH17 are controlled by the channel control device 55, and 60 is a management system that manages the entire computer system A and computer system B, and performs system mode setting, system monitoring, etc. at system startup. , 61 is a monitor display device in the management system, 62 is an input device such as a mode setting switch and a keyboard in the management system, and 70 is a device that is set at the time of system startup, for example, when a channel control device fails, input/output control device 56.57. An operation mode setting register having a mode setting such as issuing or not issuing an interface reset by a set value; 71 is an interface reset issue instruction means for instructing the issuance of an interface reset in the interface reset issue mode; 72 is provided in the channel device; , input/output control device 56
57, an interface reset issuing means for issuing an interface reset; 73, an operation mode setting register writing means for writing the value of the operation mode setting register in the management system; and 74, when a failure occurs in the channel control devices 52 to 55, other This is alternative channel control device designation means for instructing the channel control device to perform alternative processing.

Next, the operation of the configuration shown in FIG. 4 will be explained.

A specialized operator sets the value of the operation mode setting register 70 to reset the interface of the input/output control device (exclusive use of the input/output device (58, 59)) when a failure occurs in the channel control device (52, 53). It is set to a value corresponding to the mode in which the information release request (information release request) is issued or not.

This is taken into the computer system A (50) from the management system 60 when the system is started up (when the power is turned on).

For example, if there is only one channel control device (52, 53) in the computer system A, the interface reset issue mode is set and the channel control device (52, 53)
3) If a failure occurs, an interface reset is automatically issued.

In addition, when there are multiple channel control devices as in the computer system A shown in the figure, the interface reset non-issuance mode is set. For example, if the channel control device 52 fails, the channel control is performed without issuing an interface reset. The device 53 performs alternative processing.

[Problem to be solved by the invention]

In a multisystem in which input/output devices are shared by multiple computer systems each having its own channel control device and channel device as shown in FIG. 4, if a channel failure occurs during operation, Since the channel control device suspends operation while retaining exclusive rights to the input/output device, the input/output device cannot be used by other computer systems during that time.

Therefore, if there is no channel control device within the same computer system that can be used instead, the input/output device must be immediately opened to another computer system.

Furthermore, if there is a channel control device that can perform processing in place of another within the same computer system, it is possible to continue processing using that channel control device.

L7: When instructing alternative processing, the computer system having the faulty channel control device must maintain exclusive rights to the input/output device.

This is because, if exclusive rights are transferred, between the occurrence of a failure and the start of alternative processing, other computer systems can access data on the magnetic disk device that was previously exclusive to the failed channel control unit. If the software is rewritten, the logical consistency of the software will no longer be maintained.
This is because the system becomes stuck.

Therefore, if a failure occurs in the channel control device,
Immediately allow other channel control devices in the same computer system to continue processing while maintaining exclusive rights, or promptly confirm that there is no alternative channel control device and immediately It is necessary to issue an interface reset to transfer the input/output device to another computer system.

Incidentally, the value of the operating mode setting register cannot be changed by either software or the operator while the system is in operation.

Therefore, for example, in a computer system with two channel control devices, if the interface reset non-issuance mode is set and the other channel control device is also faulty, the exclusive use of the input/output device The computer system may go down without being released.

Additionally, due to configuration control of the computer system, even if the number of channel control devices that can operate while the computer system is running is changed due to installation/disconnection of channel control devices, it is not possible to perform alternative processing for channel control devices. As a result, the system sometimes went down without releasing exclusive use of the input/output device.

SUMMARY OF THE INVENTION An object of the present invention is to obtain an input/output control method that automatically determines the presence or absence of an alternative channel device when a failure occurs in a channel control device, and promptly issues an interface request if there is no alternative channel device. do.

[Means to solve the problem]

The present invention provides a channel control device with a status notification means that informs other channel control devices whether or not its own device is operable, and when a channel control device becomes inoperable, other channel control devices in the same computer system can be controlled. It inputs the status notification signal from the device, automatically determines whether it can be replaced by another channel control device, and if it cannot be replaced by another channel control device, the channel device under the faulty channel control device is An interface reset is now automatically issued.

The basic configuration of the present invention will be explained with reference to FIG.

In the figure, 1 is a computer system A, 1° is a computer system B, 3 is a management system, 4 is an input/output control device, and 5-
○ to 5-2 are input/output devices such as magnetic disks, and 6.7 is a central processing unit H (CPU).

CPU1), 8 is the main memory control unit (MCU), 9 is the main memory unit (MSU), 10.11.10゛11' is the channel control unit (IOPO, l0PIL 13 is the channel control unit?&10.11 is the computer system 12.12' is a channel device, 14.14' is a process in the channel control device such as notifying the operating state of the channel control device 10.11. 15. 15' is a processor control unit (including an operating state notification means) which outputs a signal instructing the channel device to release the exclusive use of the input/output device exclusively owned by the channel control device; 16.
16" is an OR circuit, 17.17" is an AND circuit, 18.
18" are fault occurrence notification means for notifying the management system of the occurrence of a fault in the channel control device 10 and 11, 19 is a port connecting the channel device and the input/output control device, and 20 has connection information for each computer system and each port. A proprietary information table 21 is an input/output control unit that controls input/output devices based on input signals from ports, and 22 is a service processor (SVP) that executes management of the computer system.

In a system in which a plurality of input/output devices are shared by a plurality of computer systems, exclusive use of the input/output devices is generally taken in accordance with the system. In the computer system, information on which computer system the port is connected to is given to the input/output control device as proprietary information. For example, the illustrated example tqX Uni computer system A
When port AO-An is connected to AO, if a request for exclusive use of input/output device 0 is accepted from baud 1-AO, it becomes possible for other ports A1 to An to also exclusive use of input/output device 0. Become.

In other words, input/output operations to input/output device 0 from A O = A n can be executed, but operation requests to input/output device O from other ports cannot be performed when the input/output device is in operation. A response is returned.

The illustrated proprietary information table 20 is a table of the above-mentioned proprietary information, and is for computer system A.
~An is connected to computer system B)B
This shows that O is connected.

[Effect]

The operation of the basic configuration of the present invention will be explained with reference to FIG. Refer to FIG. 1 if necessary.

In FIG. 2, 25 and 26 are channel control devices corresponding to l0P0 and 10P1 in FIG. 1, respectively.

As an example, a case where a failure occurs in 10PO will be explained according to the circled numbers shown in the figure.

■ The processor control unit 14 determines whether a failure has occurred in its own device.
is to judge.

Proprietary information release issuing means 15 for input/output devices in own device
For example, a signal with a value of 1, which means that a failure has occurred, is input to the AND circuit 17 in .

(2) If a failure has occurred in (2), an operating state notification signal CHKSTPO=1 is notified to other channel control devices.

Furthermore, the management system 3 is also notified of the occurrence of the fault by the fault occurrence notification means 18.

(2) If no fault has occurred in the own device, output an operating state notification signal CHKSTPO=0 indicating normality to other devices.

(2) If a failure has occurred in the own device, the exclusive information release issuing means 15 determines whether the other device is normal based on the signal CHKSTP1 sent from the other device (IOPI).

For example, if another device 10PI is out of order, CHKST
The signal of PI-1 is input to the OR circuit, and the AND circuit 17
A signal of CHKSTPO=1 indicating that a failure has occurred in the own device and a signal of CHKSTP1=1 indicating that a failure has occurred in another device are input.

As a result, the AND circuit 17 outputs a signal RESET RQ=1 instructing interface reset.

Further, online connection information ONLI NEI of another device is input to the OR circuit 16 .

For example, if l0PI is not connected online,
Assuming that NLINE1=O, the OR circuit outputs a signal of value 1, which is the same as when l0PI is faulty, even if CHKSTP 1 = O, since other devices are normal. Then, the AND circuit 17 outputs a signal RESET RQ-1 indicating an interface reset for releasing the exclusive use of the input/output control device.

Further, when the own device is normal or the other device is normal, the AND circuit 17 outputs a signal RESETRQ-0.

■ Output R3ETRQ-1 of proprietary information release issuing means 15
If so, the subordinate channel devices 12 (CH0 to 3) are
An interface reset signal is output to the interface including the port of the input/output control device 4.

As a result, the connection information between the computer system A and the port in the exclusive information table 20 is cleared, and the exclusive use of the input/output devices (5-0, 5-1, 5-2) by the computer system A is released.

(2) Output of AND circuit 17 RESET If RQ=0, an interface reset is not output from the subordinate channel control device 12 (CH0 to CH3) to the interface including the port of the input/output control device 4.

Then, the channel control device 11 (IOPI) automatically performs alternative processing for the input/output device that was previously exclusive to the channel control device 10 (IOPO).

Then, l0PI performs input/output processing instead.

Furthermore, in the present invention, even if functions such as data transfer become malfunctioning due to a failure in the channel control device, the interface reset output is configured by a simple hardware logic circuit, and the channel device remains operational. Therefore, it is possible to output the interface reset signal as described above.

Furthermore, in the above description, the present invention has been mainly described in the case where the 10PO has failed, but the present invention operates in the same way even when other IOPIs have failed.

〔Example〕

The present invention will be explained in detail with reference to FIG.

In the figure, 30 is computer system A, 30'' is computer system B, 32.33 is a channel control device (IOPOlIOPI) in computer system A, and 34
．． 35 is the channel control device (IOP2, l0P3) of computer system B, and 36 is the channel device (CH0
~7), CH0-3 are under the channel control device 32, CH4-7 are under the channel control device 33, and 37 is the channel device (C
H10-17), CHI0-13 are under the channel control device 34, CH14-17 are under the channel control device 35, 38 is the port, and 39 is the input/output control device A on the computer system A side. 40 is the input/output control device B on the computer system B side, which corresponds to ports 4 to 7, and 41.42 are the input/output device 1 and input/output device 2, respectively. be.

And CHO of computer system A is port 01CH4
is connected to port 1, and CHlo of computer system B is connected to port 4, CH14Ik'-to5.

I/O device 1 and I/O device 2 are system A and system B.
is shared by.

An example of input/output control of the illustrated system will be described in the case where the channel control device 32 (IOPO) has failed.

(1) l0PO causes a failure and at the same time l0P1
If the problem also occurs.

10PO issues an interface reset for the input/output control device, clears the data indicating the connection between computer system A and ports θ~3 on the proprietary information table to 0, and resets the connection between computer system A and input/output device 1.2. Disconnect.

(2) When l0PO has failed but l0PI works.

10PO does not issue an interface reset.

For example, if the CHO is updating the input/output device 1, the port 1 connected to the same computer system A will also be enabled for the input/output bag W1, so the channel control device 33 (IOPI) will update the port 1. , the channel control device 32 (IOPO) monopolizes the input/output device 1 that was previously performing update processing and automatically performs alternative processing.

〔Effect of the invention〕

According to the present invention, when channel control devices become inoperable one after another due to a failure, exclusive rights to input/output devices can be automatically and immediately released.

Therefore, the operation of the computer system becomes efficient.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the basic configuration of the present invention. FIG. 2 is an explanatory diagram of the operation of the basic configuration of the present invention. FIG. 3 is a diagram showing an embodiment of the present invention. FIG. 4 is a diagram showing a conventional input/output control method. In FIG. 1, 1: two computer systems A, 1': computer system B, 3: management system, 4: input/output control device, 5-0 to 5-2 two-person output devices, 6.7 = central processing unit , 8: Main memory control device, 9: Main memory device, 10.11.10', 11': Channel control device, 12.12': Channel device, 13: Configuration control register, 14.14': Processor control unit (operation status a notification means), 15.15°: Proprietary information release issuing means, 16.16'
: OR circuit, 17.17° : AND circuit, 18: WH damage occurrence notification means, 19: Boat, 20: Proprietary information table, 21: Input/output control unit, 22: Service processor (SVP).

Claims (1)

[Claims] Consisting of a plurality of computer systems (1, 1') that share an input/output device and an input/output control device, each computer system has a plurality of unique channel control devices (10, 11,
10', 11'), and a plurality of channel control devices (10, 11, 10', 11') in each computer system.
In a multi-system having at least one channel device (12, 12') connected to the same input/output control device (4), each of the above-mentioned channel control devices (1
0, 11, 10', 11') each has an operation status notification means (14, 14'), and if any channel control device (10) becomes inoperable due to a failure, an operation signal received from another channel control device (11) in the same computer system causes the other channel to be activated. Determine whether any of the control devices (11) are available and determine whether any of the other channel control devices (11) are available.
) is also unavailable, the connected input/output device (5-0
5-2), and proprietary information release issuing means (15, 15') that issues a proprietary release request to release the proprietary information, and when any channel control device (10) becomes inoperable, the same computer If there is another channel control device in the system that can be replaced, control the channel that can be replaced without releasing the exclusive use of the input/output devices (5-0 to 5-2) controlled by the own device (10). Enable alternative control by the device (11), and if none of the other channel control devices (11) described above can be substituted, exclusive use of the input/output devices (5-0 to 5-2) that are exclusive to the device itself. An input/output control method characterized in that the input/output control method is released so that it can be used by another computer system (1').