JPH1021202A - Network connection system of duplex computer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the network connection system which can connect computers constituting a duplex system and switch the systems without adversely adversely affecting other computers in the network. SOLUTION: The same network address is set for master-system and slave- system computers 2A and 2B, which are coupled by a signal line for monitoring the operation of the computer of the master system and a signal line for resetting the opposite computer; and both the computers are provided with exclusive control software which makes the connection function of only the master-system computer effective for the network 1, and disconnects the master-system computer from the network 1 and switches the slave-system computer as a master- system the master-system computer becomes abnormal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network connection system for connecting a computer system constituting a duplex system to a network.

[0002]

2. Description of the Related Art In order to connect a computer system constituting a dual system to a network, two computers, a main system and a slave system, constituting a dual system are different from each other so as not to adversely affect the entire network. Set the network address by software.

The master and slave computers constituting the dual system exchange data periodically via a network. In the slave system, when an abnormality is detected in the data, the master computer is activated. The system is switched based on the judgment that it is abnormal.

[0004]

Since the network addresses of the master and slave computers constituting the dual system are different, other computers connected to the network access the master computer via the network. In order to do so, it is necessary to determine which of the two computers constituting the dual system is the main system computer and access the network address of the computer.

Therefore, application software of another computer on the network becomes complicated.

When an error occurs in the main computer of the computers constituting the dual system and the system is switched, the computer in which the error has occurred remains connected to the network, so that erroneous data is output. May be output to the network, thereby causing other computers on the network to malfunction.

[0007] It is an object of the present invention to provide a network connection system capable of connecting computers constituting a dual system and switching systems without adversely affecting other computers on the network.

[0008]

[Means for Solving the Problems]

(1st invention) The present invention relates to connecting a computer system constituting a dual system of a master system and a slave system to a network, by setting the same network address to the master system and the slave computer and establishing a connection with the network. Exclusive control means is provided for the connection, the exclusive control means is means for enabling only the master computer to enable the connection function with the network, and the slave computer monitors the master computer, and When an abnormality occurs in the main computer, the main computer becomes a main computer after performing a remote reset for disconnecting the main computer from the network.

(Second Invention) According to the present invention, in connecting a computer system constituting a dual system of a master system and a slave system to a network, the same network address is set for the master and slave computers. Exclusive control means is provided for connection to the network, and the exclusive control means is configured such that the two computers are connected to each other via a digital input / output interface to take in digital outputs from each other, and when the two computers are started up, they receive digital inputs from the other computer. When there is no digital input, it waits for a digital input from the other computer while performing digital output by itself, and when there is no digital output from the other computer, it uses itself as the main system and when there is digital output from the other computer. Stop own digital output Characterized by themselves as slave repeatedly treated with different time periods from the other computer.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIG. 1 is a system configuration diagram showing an embodiment of the present invention. When a computer 2 forming a dual system is connected to another network 3 together with a network 1, the computer 2 includes a signal line for mutual monitoring and a signal line for remote reset between computers 2A and 2B to be a main system and a sub system. Connected by a signal line (transmission cable).
2C is a storage device such as a magnetic disk device shared by both computers.

The signal line for mutual monitoring is used to monitor the operation of the main computer, and the main computer changes the state of the signal line at regular intervals, and this change is monitored by the subordinate computer. If there is no state change in the signal line within a certain time, it is determined that an abnormality has occurred in the main computer.

A remote signal line is provided for resetting a partner computer by turning on the signal.

Two computers 2 constituting a dual system
The same network address is set in A and 2B. However, the network function is enabled by performing the initial setting of the network when the computer is started up, and by activating the software means shown in FIG. Exclusive control is performed so that the setting is valid.

The exclusive control processing procedure of FIG. 2 will be described below. When the software is started, first, it checks whether or not the other party is operating as a main system from the state of the mutual monitoring signal line (S1).

In this confirmation, if the other computer is not the main system, the computer itself becomes the main system (S2), initializes the network to enable the network connection (S3), and starts the application (S4). Thereafter, the state of the mutual monitoring signal line is changed at a constant cycle (S5). With this signal, a signal indicating that the master computer is operating normally is continuously sent to the slave computer.

In the judgment S1, if the partner computer is the master computer, the computer itself becomes the slave computer (S1).
6) The main computer is continuously monitored based on whether or not there is a state change in the mutual monitoring signal line for a certain period of time (S7). (S8), and when it is determined that the abnormality has occurred, a reset signal of the master computer is sent to the remote reset signal line to remotely reset the partner computer (S9). As a result of this remote reset, the network connection of the partner computer becomes invalid, and the computer itself becomes the main computer (S2), and performs the processing after the initial setting of the network (S3).

Therefore, in the present embodiment, in the computer system constituting the dual system, the same network address is set to the two computers, the main system and the sub system, and only the main system computer is always started when the computers start up. Exclusive control is performed so that the initial setting of the network is performed and the connection with the network becomes valid.

With this exclusive control, other computers accessing the dual computer system via the network can always access the primary computer by always accessing the same network address. Becomes very simple.

Further, the computer system constituting the dual system is designed so that when an abnormality occurs in the main computer,
System switching is performed by remotely resetting the master computer from the slave computer. This allows
It is possible to prevent an abnormal computer from outputting erroneous data on a network.

(Second Embodiment) In the configuration of FIG.
Both computers 2A and 2B need to be connected to each other by a signal line (transmission cable) for exclusive control. Also, exclusive control software using input / output interfaces for signal lines is required.

Furthermore, when the two computers perform exclusive control of switching between the master system and the slave system at the time of startup, if the other computer has already been started or the other computer has not been started yet, the switching can be performed without any problem. However, when both computers are started at the same time, exclusive control is performed so that both computers become the primary computers, and there is a risk that simultaneous access and data rewriting may be performed on the shared storage device 2C and the like.

The present embodiment for solving these problems will be described below.

In the configuration of FIG. 1, computers 2A,
Instead of using a transmission cable (signal line) for signal exchange for exclusive control between 2B, digital input / output functions of both computers are used.

As a result, the connection between the two computers 2A and 2B by the transmission cable and the interface using the connection line are not required.

Next, the exclusive control of the two computers 2A and 2B enables the exclusive control even when they are started simultaneously in the processing shown in FIG. Hereinafter, the exclusive control will be described with reference to FIG.

The activated computer waits for a digital input from the partner computer within a predetermined time (S1).
1) When there is no digital input for a fixed time (S
12) When digital output is performed (S13), a digital input is waited for a fixed time at the same time (S14).

If there is a digital input within the waiting time (S15), the computer stops its digital output (S16), and after a relatively long delay time of several seconds (S17), the computer receives a digital signal from the other computer. The process returns to waiting for input (S11).

At this time, a random number is used as the delay time, and the random number is determined to be different from each other, such as a serial number unique to a computer. As a result, it is possible to perform exclusive control that allows time for determining whether or not there is a digital output from a partner in both computers.

In step S15, when there is no digital input from the partner computer, the started computer continues to perform digital output using itself as the main system (S18), and performs processing on the main system such as mounting the shared storage device 2C (S19). Start.

Next, if there is a digital input from the partner computer in the judgment in the process S12, the started computer waits for a digital input for a certain period of time as its own slave computer (S20). When there is an input (S21), a repetitive process for returning to waiting for a digital input again (S20) is performed.

When there is no digital input from the partner computer in this repetitive processing, the digital output is performed by itself (S22), and the digital output of the main system is continued (S18).

Therefore, in this embodiment, both computers check whether or not there is a digital input at the time of their startup, and if there is a digital input, determine that the other computer is the master and switch themselves to the slave.

When there is no digital input, instead of switching to the main system immediately, instead of waiting for digital input from the other computer for different times while performing digital output, both computers can be started simultaneously. Prevents the computer from switching to the main system.

[0034]

As described above, according to the present invention, the same network address is set to the master and slave computers, only the master computer enables the network connection function, and the master computer is connected to the master computer. When an error occurs, the master computer is disconnected from the network and the slave computer switches to the master computer for exclusive control, so that other computers on the network can always access the same address. The software configuration is simplified. Further, when an error occurs in the main computer, erroneous data is not output on the network.

Also, the present invention utilizes a digital input / output interface to input / output the status of both computers, and checks the presence / absence of digital output from the other computer at a time period different from that of the other computer. However, since exclusive control for switching to the master or slave system is performed, it is not necessary to connect both computers with a transmission cable, and it is possible to eliminate the inconvenience of switching both computers to the master system when both computers start up at the same time. it can.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an embodiment of the present invention.

FIG. 2 is a procedure of an exclusive control process in the embodiment.

FIG. 3 shows a procedure of an exclusive control process according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Network 2 ... Computer system which comprises a duplex system 2A, 2B ... Computer 2C ... Shared storage device 3 ... Other computer on a network

Claims (2)

[Claims] In connecting a computer system constituting a dual system of a master system and a slave system to a network, the same network address is set for the master system and the slave system, and exclusive control means is used for connection to the network. Provided, the exclusive control means, means for only the main computer to enable the connection function with the network, the subordinate computer monitors the main computer,
A dual computer network connection method, wherein a remote computer that disconnects the primary computer from the network when a failure occurs in the primary computer, and then becomes a primary computer by itself. 2. When connecting a computer system constituting a dual system of a master system and a slave system to a network, the same network address is set to the master system and the slave computer, and exclusive control means is used for connection to the network. The exclusive control means, wherein the two computers are connected to each other by a digital input / output interface to receive each other's digital output, and when the two computers start up, they wait for a digital input from the other computer, and when there is no digital input, The process of waiting for digital input from the partner computer while performing digital output by itself, stopping itself when there is no digital output from the partner computer, and stopping its own digital output when there is digital output from the partner computer The other computer A dual computer network connection method characterized in that the computer is repeatedly used at different time periods from each other.