JPS6344248A - Automatic switching system for inter-duplex system communication - Google Patents

Abstract

PURPOSE:To switch a system without taking synchronization, by constituting the system so that one adaptor of an opposite system can be recognized, in communication between dualized systems performed through a local area network. CONSTITUTION:Each system in a master system can perform the communication among the systems in the master system only by applying the data to a node 51 through a link adaptor 6. For example, it is not necessary to be conscious of whether a communication opponent is a system B1, or a system B2, judging from the standpoint of a system A1. At this time, when a fault is generated in the system B2, the switching of the master/slave system is performed in the communication being performed through a network 5' between dualized control programs executed in the systems B1 and B2. The fact is informed from the master system to a supervisory device 3, and also, the communication control program for the link adaptor on the master system is switched synchronously with the above switching.

Description

[Detailed description of the invention] [Summary] Link adapter (LINA) and local area network
In communication between two duplexed systems via a network (LAN), the main system is connected to a monitoring device (SUP) under the control of a duplex control program executed within each duplexed system. Notify the monitoring device (
StlP), by providing a mechanism to control the switch circuit and connect the primary side system of each duplex system to the local area network (LAN), the duplex control performed in each of the above systems is implemented. When the program switches between the main system and the slave system and notifies the main system to the monitoring device (SUP), the monitoring device (SUP) connects to the local area network (LAN).
The switch circuit for the main system side link adapter (L
INA) to enable continuous communication between the main systems of the duplex system.

[Industrial application field]

The present invention relates to an automatic switching method for communication between two duplex systems via a link adapter (LINA) and a local area network (LAN).

With the recent spread of computer systems, for example, so-called local area networks (local area networks) using optical fibers, etc.
Construction of data processing systems using LAN is becoming popular.

In this case, as the data processing system goes online,
It is necessary to improve the reliability of the system, and one of these is, for example, the local area network (LA
N) A system in which each of the above systems is duplicated has come into practical use.

Via the above local area network (LAN),
When communicating between the duplexed systems, it is necessary that the application programs executed on the respective systems (specifically, the systems on the main side of the duplexed system) can communicate effectively with each other.

[Prior art and problems to be solved by the invention] FIG. 2 is a diagram illustrating a conventional automatic switching system for communication between duplex systems.

Now, for convenience of explanation, two duplicated systems A1 and each system A1 (11) of system B2,
A2 (12), system Bl (21), B2
(22) between each corresponding node (N
il, N12. N21. Consider a case where communication is performed via a network (N22) and a local area network (LAN) 5.

In this case, each system Al(11), A2(12),
Or, in the application program executed on each of systems Bl (21) and B2 (22), first, 2
In each of the two systems A1 and B2, a master/slave relationship is determined by communication using a specific protocol between one-to-one local area networks (LANs) 5' via link adapters (LINA) 6, and system (system At(11) or system Bl(21) in this figure) is the partner system A1.
Or, when attempting to communicate with the main system of system B2, the main system, for example, system Al (11)
From this point, the other system (ie, system B 2) can see two systems: the main system Bl (21) and the slave system B2 (22). That is, link adapter (LINA) 6
There will be two.

Therefore, by communicating with each system again using the protocol on the other side, the main system of the other system,
Or it was necessary to recognize the subordinate system.

Furthermore, in this case, the communication control program that controls the link adapter (LINA) 6 and the other party's application program beyond it operate independently of each other.
It was necessary to maintain software synchronization (ie, responses and confirmations) between the two communication control programs.

Normally, the slave system is often down, so even if you communicate according to the above protocol, you may not receive a response.In this case, it is recognized that there is no response, It will be recognized that the slave system is down.

In view of the above-mentioned conventional drawbacks, the present invention makes it necessary to configure the communication path between application programs and synchronize communication control programs by always making the link adapter (LINA) of the other system visible as one. The purpose of this invention is to provide an automatic switching method for communication between duplex systems without any interference.

[Means for solving problems]

FIG. 1 is a diagram showing a configuration example of an automatic switching method for communication between duplex systems.

In the present invention, in the communication between the two duplex systems 1.2 via the link adapter (LINA) 6 and the local area network (LAN) 5, within each duplex system 1.2, means for notifying the monitoring device 3 of the main system side (11, or 12, 21. or 22) under the control of the duplex control program to be executed; and the monitoring device 3
Based on instructions from
A switch circuit 41. which connects the main side system of the duplex system to each node 51 on the LAN) 5.
42, and in the communication between the duplex system 1.2, the link adapter (L
INA) is also configured to continuously communicate with the other party's main system by automatically switching to the main system side.

[Effect]

That is, according to the present invention, in communication between two duplex systems via a link adapter (LINA) and a local area network (LAN),
Double otherness executed within each duplicated system? 11
Monitoring device (SUP) on the main system side based on program control
The monitoring device (SUP) is provided with a mechanism to control the switch circuit and connect the main system of each duplex system to the local area network (LAN). When the redundancy control program executed in each system switches between the main system and the slave system and notifies the monitoring device (SUP) of the main system, the monitoring device (SUP) switches to the local area network (LAN). Since the circuit is automatically switched only to the link adapters (LI to A) on the main side, and communication between the main sides of the duplexed system is performed continuously, the local area network ( Communication between redundant systems via LAN)
This has the effect of allowing you to switch between the main system and the slave system on the other side without being aware of it.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

The above-mentioned FIG.
P) 3. Changeover switches 41, 42. and a duplication control program executed in each system are necessary means to implement the present invention. Note that the same reference numerals indicate the same objects throughout the figures.

The automatic switching method in communication between duplex systems according to the present invention will be explained below with reference to FIG.

It is now assumed that the main system A111 of the system A1 and the main system B121 of the system B2 are communicating.

Specifically, the communication control program connects the link adapter (LIN) based on the instructions of the application program in each main system.
A) Controls 5 and connects to a local area network (LA
N) Communication between both systems is carried out via 5.

At this time, the switch circuits 41 and 42 each select the main system under control from the monitoring device (SUP) 3.

Therefore, each main system connects to the local area network via the corresponding link adapter (LINA) 6.
(LAN) 5': Opposite node (OUL) 51
By simply turning on the monitor, communication between the main systems (specifically, communication between application programs running on each system) can be performed, and the communication between the other systems (for example, when viewed from A111) is possible. There is no need to be aware of whether the communication is with B121 or B222.

Here, for example, a failure occurs on the system B2 side, and each system B121. When switching between the main system and the slave system is performed by communication between the redundant control programs executed in each system B 221 via the local area network (LAN) 5'', the system on the main side (in this example, System B 222) notifies the monitoring device (SUP) 3 of this fact, and the link adapter (LTNA) on the main side
The communication control program for 6 is also switched in synchronization.

In monitoring device (SUP) 3, switch circuit pressure 2
control the local area network (LAN) 5
The link adapter (LINA) 6 connected to the node (OUL) 51 is connected to the main system side (that is, the system B 222 side)
It works like switching to .

Therefore, at this point, the timing of data transfer between the local area network (LAN) 5 and the link adapter (LINA) 6 of the system 8222 example is controlled by the switched communication control program. This means that the synchronization is achieved.

Therefore, the application program running on system A111 is the switched application program of main system B222 on the other side, and the link adapter (LINA) controlled by the communication control program on system B222 side.
6, the system A111
Inputting data from a computer to a local area network (LAN) can be done without being aware of switching systems on the other side, and there is no need to synchronize between programs as in the conventional method. It has the characteristics of an invention.

〔Effect of the invention〕

As explained above in detail, the automatic switching method for communication between duplex systems of the present invention uses a link adapter (LIN
A) In communication between two duplexed systems via a local area network (LAN), the main side is controlled by the duplex control program executed within each duplexed system. Monitoring device (SUP
), and the monitoring device (SUP) controls the switch circuit to connect the main system of each duplex system to the local area network (LAN).
By providing a mechanism to connect to the monitoring device (SUP), the redundancy control program executed in each of the above systems switches between the main system and the slave system, and connects the main system to the monitoring device (SUP).
When notified, the monitoring device (SUP) automatically switches the switch circuit for the local area network (LAN) only to the link adapter (LINA) on the main side, and communication between the main sides of the redundant system is maintained. Since this system is designed to perform continuously, communication between redundant systems via a local area network (LAN) can be performed without being aware of switching between the main system and the slave system on the other side. be.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a configuration example of an automatic switching system for communication between duplex systems according to the present invention. FIG. 2 is a diagram illustrating a conventional automatic switching method for communication between duplex systems. It is. In the drawings, 1 is a system A, and 11 is a system Al. 12 is system A2, 2 is system B. 21 is system 81. 22 is a system 82. 3 is a monitoring device (SUP), and 4L42 is a switch circuit. 5.5 is a local area network (LAN). 51 is a node (OLU). 6 is a link adapter (LINA). Nil to N22 are nodes. are shown respectively.

Claims (1)

[Claims] In communication between two duplex systems (1, 2) performed via a link adapter (LINA) (6) and a local area network (LAN) (5),
Under the control of the duplex control program executed within each duplex system (1, 2), the main system (11 or 1
2, 21, or 22) to a monitoring device (3); and each node (51) on the local area network (LAN) (5) based on instructions from the monitoring device (3).
A switch circuit (41, 42) is provided to connect the main side system of the redundant system, and communication between the redundant system (1, 2) switches between the main system and the slave system at the same time. An automatic switching method for communication between duplex systems, characterized in that the link adapter (LINA) also automatically switches to the main system side, thereby continuously communicating with the other main system.