JPH03265036A - Duplexing computer system - Google Patents

Abstract

PURPOSE:To surely identify the abnormality of the other machine and the disconnection of a cable providing one set of switching device being in common to two sets of computer devices, and executing a switching command and the information of a status through the signal line of 2 bits. CONSTITUTION:By detecting a fact that (0, 0) is inputted to terminals AS1, AS2 or BS1, BS2, the disconnection detection of signal lines 6A, 6B is executed, and by deciding a fact that (1, 1) is inputted to the terminals AS1, AS2 or BS1, BS2, the abnormality of computer devices 1A, 1B is decided. When the abnormality of the computer device is the abnormality of an A system, (0, 1) is outputted to output terminals O1, O2, and when it is the abnormality of a B system, (1, 0) is outputted to the terminals O1, O2. In such a manner, the abnormality of the other machine and the disconnection of a cable can be identified surely.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an improvement in a redundant computer system that requires high real-time performance and high reliability.

(Prior Art) Conventionally, in this type of redundant computer system, two computer devices each executing application processing are installed in parallel, and one of them is used as an online machine and the other as a standby machine. At the same time, the standby machine constantly monitored the status of the online machine via a predetermined cable, and a control system was adopted in which the status of the online machine was automatically promoted from the standby machine to the online machine when any abnormality was detected.

However, in such conventional redundant computer systems, since the standby computer must constantly monitor the status of the online computer, a portion of its processing capacity is used to monitor the other side. Therefore, there was a problem in that it interfered with the original application processing.

In addition, the computer device that is set as a standby machine is immediately promoted to an online machine in response to the computer device on the online machine side being determined to be abnormal, so if the monitoring cable is disconnected, etc. There is also the possibility that a situation may arise in which both computer devices compete as online devices by misunderstanding that the other party's machine is malfunctioning.

(Problems to be Solved by the Invention) As mentioned above, in the conventional redundant computer system, the standby computer must constantly monitor the status of the online computer, so the processing A portion of the computer's capacity must be used to monitor the other party, which may interfere with the original application processing.In addition, if the cable connecting the other party's computer is disconnected, it may be necessary to use the There is a problem in that both computer devices go online at the same time due to the misidentification as a failure.

This invention was made in view of the above problems,
The purpose of this is to enable both computer devices to execute application processing by making full use of their capabilities, and to ensure that even if a cable break occurs, it will not be mistaken as a malfunction in the other party's computer. An object of the present invention is to provide a redundant computer system that prevents the occurrence of problems.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the first invention of this application includes two computer devices parallel to each other that respectively execute application processing; one switching device provided in common to all computer devices, and one switching device provided for each computer device, each connected to its own computer device via a shared memory, and connected to the switching device. It also consists of two duplex control modules that exchange information via two systems of 2-bit signal lines, one for switching command notification and one for status notification, and each of the duplex control modules has a shared The status of the computer device notified via the memory is notified to the switching device via the status notification signal line, and the status is notified via the shared memory in accordance with a command transmitted from the switching device via the switching command notification signal line. The switching device is provided with a function of giving instructions to its own computer device, and the switching device monitors the abnormality of each computer device via a status notification signal line, and in response to the detection of an abnormality occurrence, the switching device The present invention is characterized in that it is provided with a function of giving a startup command to a backup computer device via a switching command notification signal line.

In addition, in the second invention of this application, in order to achieve the above object, the 2-bit signal line for notifying the switching command has the bit order exchanged with each other after being output from the common terminal on the switching device side. It is characterized in that it is wired to terminals on the side of each duplex control module.

(Operation) According to such a configuration, in the first invention, first,
Work that was conventionally performed by the computer itself is now entrusted to one switching device and two duplex control modules, allowing each computer to fully utilize its processing power for its original application processing. be able to.

In addition, notification of the switching command and notification of the status are each performed via a 2-bit signal line, so for example, 00
By assigning statuses such as (disconnection state), 01 (online state), 10 (offline state), 11 (abnormal state), etc., it is possible to reliably identify an abnormality in the other party's machine and a cable breakage.

Further, according to the second invention of this application, after the 2-bit signal line for switching command notification is output from the common terminal on the switching device side, the bit order is exchanged with each other for each duplex control module. Since the wiring is to the side terminal, for example, by assigning the switching command as 10 (online switching command) or 01 (offline switching command), the same switching command content can be sent to both duplex control modules. It is possible to reliably prevent this from occurring.

(Embodiment) Fig. 1 is a block diagram showing an embodiment of a duplex computer system according to the present invention, Fig. 2 is a flowchart showing control details on the switching device side, and Fig. 3 is a duplex control module. 3 is a flowchart showing control details on the side.

As shown in FIG. 1, the redundant computer system of this embodiment includes two parallel computer devices IA and IB that each execute application processing, and One common switching bag! ! 2, and a shared memory 3 provided for each of the computer devices IA and IB, respectively.
A, 3B are connected to own computer devices IA, IB, and two systems of 2-bit signal lines 5A, 5B and 5B are connected to the switching device 2, one for switching command notification and one for status notification. 6A.

It is composed of two duplex control modules 4A and 4B that communicate information via 6B.

In each of the duplex control modules 4A and 4B,
The status of the computer devices IA and IB notified via the shared memories 3A and 3B is notified to the switching device 2 via the status notification signal lines 6A and 6B, and the switching device 2 also sends a switching command notification signal line 5A. , 5B is provided with a function of giving instructions to its own computer devices IA, IB via the shared memories 3A, 3B.

The switching device 2 also includes a status notification signal line 6A.
, 6B to each computer device IA.

The switching command notification signal line 5A monitors abnormalities in the IB and responds to detection of abnormality occurrence.

Backup computer equipment (IA) via 5B
, or IB).

Furthermore, the 2-bit signal lines 5A, 5 for notifying the switching command
After B is output from the common terminals 01 and 02 on the switching device 2 side, it is wired to the terminals II and 12 on the respective duplex control modules 4A and 4B with the bit order exchanged.

Next, the operation of the duplex computer system having the above configuration will be explained with reference to the flowcharts of FIGS. 2 and 3.

When the process starts in FIG. 2, first the terminals AS,
By detecting that (0, 0> has been manually input to AS2 or BS, □BS2), disconnection of the signal lines 6A and 6B is detected (step 201).

Here, if a disconnection occurs in any of the signal lines, a disconnection alarm process is performed (step 202).

Next, the (1
, 1) is input, it is determined whether the computer devices IA, IB are abnormal.

Here, if it is normal (step 203 NO), the abnormality disconnection detection process (step 201) and the abnormality determination process (step 203) are repeated.

In contrast, any computer device IA, IB
When an abnormality occurs in (step 203 YES), if the abnormality is an A system abnormality, the output terminals 01 + 02 are (
0, 1) (step 205), and if the B system is abnormal, (1°0) is output to the output terminals o, o2 (step 206).

Here, as described above, there are two signal lines 5A.

5B is output from the common terminals o, , o2 on the switching device 2 side, and then sent to the terminals 1., . ．． 12, so when (0, 1) is output from output terminals o, o2, a standby command is issued to the A-system computer device IA, and a standby command is issued to the B-system computer device IB. Online instructions are given.

Conversely, when (1, O) is output from the output terminals o, , o2, an online command is given to the A-system computer device IA, while the B-system computer device IB
A standby command is given to the

In this way, opposite commands are always given to both computer devices IA and IB, and the same command is given at the same time, thereby making it possible to prevent conflicts between the computer devices.

After that, check for normal responses from each computer device IA and IB (step 207), and if there is a normal response, the process ends, but if there is no normal response (step 207).
07 NO), an alarm process is performed as both sides are abnormal (step 208).

Next, the processing on each of the duplex control modules 4A and 4B will be explained with reference to the flowchart in FIG.

In FIG. 3, when the process starts, first terminal 1. ,
Disconnection detection is performed by determining that (0,0) is input to I2 (step 301).

If it is determined that the wire is disconnected (step 301 YES),
A predetermined disconnection alarm process is performed (step 302).

Next, by determining that the signals at the terminals I+ and 12 have changed, it is confirmed that a switching command of some kind has arrived from the switching device 2 (step 303).

Here, if the switching process does not arrive (step 303N
O), Next, based on predetermined flags on the shared memories 3A and 3B, it is determined whether or not any abnormality has occurred in the own computer devices IA and IB (step 3).
10) If an abnormality has occurred (step 310 YES)
, signal line 6A.

6B to notify the switching device 2 of the abnormal status (step 311).

On the other hand, if a switching command of some kind arrives from the switching device 2 (step 303 YES), it is determined whether the command content is online or standby (step 304).

Then, if it is an online process, an online command is sent (step 305), and if it is a standby command, a standby command is sent (step 306) to the shared memories 3A, 3, respectively.
The information is transmitted to the computer devices IA and IB via B.

Thereafter, after waiting for a normal response to arrive from the computer devices IA and IB (step 3o7), the switching device 2
A normal response is returned to (step 308).

At this time, if a normal response does not arrive from the computer device (step 307), an abnormal response is output to the switching device 2 (step 309).

In this way, according to the system of this embodiment, all the various processes related to the monitoring of each computer device flA, IB are performed by the switching device 2 and the duplex control modules 4A, 4B, so that the individual computer devices IA, IB, The IB can concentrate on the original application processing, thus making full use of the processing power of those computer devices.

In addition, since the signal lines 5A, 5B and 6A, 6B each consist of 2 bits, it is possible to easily distinguish between normal signal transmission and disconnection, which prevents a disconnection from being mistaken for a malfunction in the other device. Therefore, it is possible to avoid simultaneous operation of both computer devices.

Further, the signal lines 5A and 5B are connected to a common terminal o on the switching device 2 side.
,, after being output from 02, terminal 1 of each duplex control module 4A, 4B side with the bit order changed mutually.
．． , I2, the contents of the command given from the switching device 2 to each control module 4A, 4B are as follows.
The meanings and contents are always opposite, and this also makes it possible to reliably avoid simultaneous operation of both computer devices.

[Effects of the Invention] As is clear from the above description, according to the present invention, in this type of redundant computer system, the capabilities of individual computer devices can be fully utilized for application processing. Further, malfunctions due to disconnection of the monitoring cable, etc. can be reliably prevented.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of a duplex computer system according to the present invention, Fig. 2 is a flow chart showing the control contents of the switching device, and Fig. 3 is a flow chart showing the control contents of the duplex control module. It is. IA, IB...Computer device 2...Switching device 3A, 3B...Shared memory

Claims (2)

[Claims] (1) Two computer devices that are parallel to each other and each executes application processing, one switching device that is provided in common to the two computer devices, and a switching device that is provided for each of the computer devices, respectively. Two units that are connected to their own computer device via a shared memory and also exchange information with the switching device via two systems of 2-bit signal lines, one for switching command notification and one for status notification. each duplex control module notifies the switching device via the status notification signal line of the status of the computer device notified via the shared memory, and also controls the switching device. The switching device is provided with a function of giving an instruction to its own computer device via a shared memory in accordance with a command transmitted from the device via a switching command notification signal line, and the switching device is provided with a function to give instructions to its own computer device via a shared memory, A function is provided for monitoring abnormalities in the computer device and, in response to detection of the occurrence of an abnormality, giving a startup command to the backup computer device via the switching command notification signal line; A redundant computer system featuring: (2) After the 2-bit signal line for switching command notification is output from the common terminal on the switching device side, it is wired to the terminal on each duplex control module side with the bit order mutually switched. The duplex computer system according to claim 1, characterized in that: