JPH08249200A - Redundant system computer system - Google Patents

Abstract

PURPOSE: To allow a computer, either of a normal service system computer and a standby system computer, to execute diagnostic chechs on itself even if it is not connected to an object device so as to improve reliability. CONSTITUTION: A redundant system computer system where a turn-back control means 10 in a switch controller 3 returns a signal transmitted from the computer which is not connected to the object device 6 to the computer, either of the normal service system computer 1 and the standby system computer 4, and self-diagnosis means 11 and 12 in the computer execute a self-diagnosis processing based on a signal returned from the turn-back control means is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a redundant computer system in which a regular computer or a standby computer is selectively connected to a target device via a switching control device, and particularly to a computer not connected to the target device. A redundant computer system capable of self-diagnosis and improving reliability.

[0002]

2. Description of the Related Art Conventionally, in the field of a system consisting of a computer and peripheral devices, a redundant computer system in which a regular computer or a standby computer is selectively connected to a target device through a switching control device has been widely used. There is.

FIG. 4 is a block diagram showing the configuration of this type of redundant computer system. In this redundant computer system, the regular computer 1 is connected to the switching control device 3 via the regular control line 2, and the standby computer 4 is connected to the switching control device 3 via the standby control line 5. ing. The switching control device 3 selectively connects either one of the regular computer 1 and the standby computer 4 to a peripheral device (target device) 6 such as a printer. Here, the regular computer 1 is selected. It is physically connected to the peripheral device 6.

Here, the normal system computer 1 and the standby system computer 4 have the same configuration as each other, and the peripheral device 6 can be accessed from the peripheral device control sections 1a and 4a, which are individually provided, through the switching control device 3. . Further, the regular computer 1 and the standby computer 4 can perform self-diagnosis by accessing the peripheral devices 1a and 4a.

[0005]

However, in the redundant computer system as described above, when the regular computer 1 makes a self-diagnosis by accessing the peripheral device 6 through the switching control device 3, the standby computer 4 is better than the standby computer 4. Peripheral device 6
There is a problem that the self-diagnosis cannot be performed because the user cannot access the.

That is, in the standby system computer 4, even if there is some abnormality in the control line leading to the peripheral device control section 4a or the switching control device 3, no abnormality is detected, and the standby system computer 1 is switched. When the peripheral device 6
However, there is a problem that the reliability is significantly deteriorated due to the impossibility of using.

The present invention has been made in consideration of the above-mentioned circumstances, and one of the normal system computer and the standby system computer, which is not connected to the target device, can be self-diagnosed and the reliability can be improved. The purpose is to provide a system.

[0008]

The invention according to claim 1 is a redundant computer system in which a regular computer or a standby computer is selectively connected to a target device through a switching control device. The switching control device has a loopback control means for returning to the computer a signal transmitted from the computer that is not connected to the target device among the regular computer or the standby computer, and both computers are The redundant computer system includes a self-diagnosis unit that executes a self-diagnosis process based on a signal returned from the loopback control unit.

According to a second aspect of the present invention, in the redundant computer system according to the first aspect, the self-diagnosis means is based on a comparison result of the transmitted signal and the returned signal. This is a redundant computer system that executes self-diagnosis processing.

[0010]

Therefore, in the invention corresponding to claim 1, by taking the above-mentioned means, the loopback control means in the switching control device is one of the normal system computer and the standby system computer.
The signal transmitted from the computer not connected to the target device is returned to the computer, and the self-diagnosis means in the computer executes the self-diagnosis processing based on the signal returned from the loopback control means. Further, the self-diagnosis can be executed even by the computer which is not connected to the target device among the standby system computers, and thus the reliability can be improved.

In the invention according to claim 2, the self-diagnosis means according to claim 1 executes the self-diagnosis process based on the result of comparison between the transmitted signal and the returned signal. The same action as the action corresponding to Item 1 can be achieved.

[0012]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a redundant computer system according to an embodiment of the present invention.
The same reference numerals are given to the same portions as those and detailed description thereof will be omitted, and only different portions will be described here.

That is, the system of this embodiment enables self-diagnosis of the computer which is not connected to the peripheral device 6 among the regular computer 1 and the standby computer 4.
Specifically, compared to the device shown in FIG. 4, the switching control device 3 sends a signal sent from the computer, which is not connected to the peripheral device 6, of the regular computer 1 and the standby computer 4, to the computer. And a standby system computer 4 are provided with self-diagnosis processing units 11 and 12 for executing self-diagnosis processing based on the signals returned from the return control unit 10, respectively. It has been configured. The self-diagnosis processing unit 11 is provided in the regular computer 1, and the self-diagnosis processing unit 12 is provided in the standby computer 4.

The turn-back control section 10 operates in response to the switching operation in the switching control device 3.
As shown in FIG. 2, a regular computer 1 and a standby computer 4
Of the control lines 2 and 5 from the computer 1 or 4 which is not connected to the peripheral device 6 among the control lines 2 and 5 from the switch control device 3 to the switching control device 3, the transmission line and the reception line in the control lines 2 and 5 are targeted. And are connected in pairs.

For example, as in the case of using RS232C, the control lines 2 and 5 have transmission data SD and reception data R.
D, transmission request RS, transmission possible CS, data set ready D
When composed of a plurality of signal lines respectively corresponding to R, data terminal ready ER, and carrier detection CD, the loopback control unit 10 sets the transmission data SD and the reception data RD as a set, and makes a transmission request RS and a transmission enable CS. Data set ready DR, data terminal ready ER and carrier detection C
The relay 10a is used so that D and D are connected as a set.

Further, the self-diagnosis processing units 11 and 12 operate in the computers 1 and 4 which are not connected to the peripheral device 6, and, for example, when the transmission request SD is transmitted, it is abnormal depending on whether or not the transmission permission CS is received. It is possible to determine whether or not there is an error, and it is also possible to determine whether or not there is an abnormality depending on whether or not the same received data RD as the transmitted data is received when the transmitted data SD is transmitted.
When R is transmitted, the presence / absence of abnormality can be determined by whether or not the data terminal ready ER and the carrier detection CD are received. Here, the transmission data S
The determination process when D is transmitted can be executed by comparing the transmission data and the reception data RD.

Next, the operation of the redundant computer system configured as described above will be described. Now, the regular computer 1 is connected to the peripheral device 6 via the switching control device 3,
On the contrary, the standby computer 4 is not connected to the peripheral device 6 by the switching control device 3.

In the standby system computer 4, the loopback control unit 10 connects the transmission data SD and the reception data RD among the signal lines in the standby system control line 5 to each other, and the transmission request RS and the transmission enable. CS is connected to each other, and data set ready DR and data terminal ready ER
And the carrier detection CD are connected to each other.

Therefore, in the self-diagnosis processing section 12 of the standby system computer 4, as shown by the arrow in FIG.
When D is transmitted, the presence or absence of an abnormality is determined by whether or not the transmission enabled CS is received. When there is no abnormality, and subsequently, when the transmission data SD is transmitted, the transmission data and the reception data RD are compared, and the reception data S identical to the transmission data SD
Whether or not there is an abnormality is determined by whether or not D has been received. Similarly, when there is no abnormality, when data set ready DR is transmitted, data terminal ready ER and carrier detection CD
The presence or absence of abnormality is determined by whether or not is received. Here, when there is no abnormality, the self-diagnosis processing unit 12 of the standby-system computer 4 diagnoses its own system as normal. On the other hand, when even one of the above-mentioned determinations determines that there is an abnormality, an alarm is output to notify the abnormality.

By the switching operation of the switching control device 3,
When the standby computer 1 is disconnected from the peripheral device 6 and the standby computer 4 is connected to the peripheral device 6, the loopback control unit 1
0 connects the normal system control line of the normal system computer 1 in the same manner as described above. In addition, the self-diagnosis processing unit 11 of the regular computer 1
Performs the self-diagnosis process by determining the presence or absence of abnormality as described above.

As described above, according to the present embodiment, the loopback control unit 10 in the switching control device 3 has the normal-use computer 1
Alternatively, a signal transmitted from the computer 4 which is not connected to the peripheral device 6 among the standby system computers 4 is returned to the computer 4, and the self-diagnosis processing unit 12 in the computer 4 is returned from the loopback control unit 10. Since the self-diagnosis processing is executed based on the signal, the regular computer 1 and the standby computer 4
Among them, the self-diagnosis can be executed even by the computer that is not connected to the peripheral device 6.

Thus, when an abnormality occurs, an alarm is output to notify the abnormality to prompt the repair of the abnormal portion, thereby preventing an unexpected abnormality at the time of switching,
Therefore, reliability can be improved.

Further, according to the present embodiment, the self-diagnosis processing unit 12 executes the self-diagnosis processing based on the comparison result between the transmitted signal and the returned signal, so that a slight transmission error occurs. Also, the abnormality can be detected.

In the above embodiment, the case where the presence or absence of abnormality is determined by comparing the transmission data SD and the reception data RD and determining whether the reception data RD is the same as the transmission data SD has been described. Transmission data S
Even if the presence / absence of abnormality is determined when the reception data RD is received when D is transmitted, the same effects can be obtained by implementing the present invention in the same manner. Other,
The present invention can be implemented with various modifications without departing from the gist thereof.

[0025]

As described above, according to the first aspect of the present invention, the loopback control means in the switching control device is transmitted from the computer which is not connected to the target device among the regular computer and the standby computer. The signal is returned to the computer, and the self-diagnosis means in the computer executes the self-diagnosis processing based on the signal returned from the loopback control means, so it is not connected to the target device among the regular computer and the standby computer. It is possible to provide a redundant computer system that can improve reliability because even one computer can execute self-diagnosis.

According to the invention of claim 2, claim 1
Since the self-diagnosis means corresponding to the step 1 performs the self-diagnosis processing based on the comparison result between the transmitted signal and the returned signal, a redundant computer system capable of achieving the same effect as that of claim 1 is provided. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a redundant computer system according to an embodiment of the present invention,

FIG. 2 is a schematic diagram for explaining a connection configuration of a loopback control unit and a control line around the loopback control unit in the embodiment,

FIG. 3 is a schematic diagram showing a signal path during self-diagnosis processing in the same embodiment;

FIG. 4 is a block diagram showing a configuration of a conventional redundant computer system.

[Explanation of symbols]

1 ... Regular computer, 1a, 4a ... Peripheral device controller, 2 ...
Normal system control line, 3 ... Switching control device, 4 ... Standby system computer, 5 ... Standby system control line, 6 ... Peripheral device, 10 ... Return control unit, 10a ... Relay, 11, 12 ... Self-diagnosis processing unit.

Claims (2)

[Claims] 1. A redundant computer system in which a normal system computer or a standby system computer is selectively connected to a target device via a switching control device, wherein the switching control device is the normal system computer or the standby system computer. Among them, it has a loopback control means for returning a signal transmitted from the computer that is not connected to the target device to the computer, the both computers, respectively self-diagnosis based on the signal returned from the loopback control means A redundant computer system comprising self-diagnosis means for executing processing. 2. The redundant computer system according to claim 1, wherein the self-diagnosis means executes self-diagnosis processing based on a comparison result between the transmitted signal and the returned signal. Redundant computer system.