JPS6321943B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a switching system for dual-system computers, and particularly to a switching system for dual-system computers that is optimal for computers in which both systems share different tasks and one system requires continuity. In a multiplex system using computers, the load sharing multiplex system (LOAD SHARED SYSTEM) in which computers share the processing of multiple tasks is basically a switching method that temporarily puts the system in a standby or stopped state. It's started and running. On the other hand, when computer operations require high continuous processing performance, one of the duplicated computers is used as the main system and the other as the slave system, creating a standby dual system (DUPLEX) system. The process is being performed and is on standby. In recent years, in order to increase the operating rate of each computer, duplex systems have adopted standby duplication, while the backup standby side is used to perform other tasks, and when the main task is backed up, it is stopped. The LOAD SHARED DUPLEX method has been adopted. In these devices, switching from the main system to the slave system as a standby dual system is particularly important when the main system fails, the slave system recognizes the failure information of the main system, and based on that judgment, the slave computer immediately switches to the main system. Measures are being taken to continue operations. In addition, in a load-balanced system, business switching is
First, stop one function, start the operation of the own system to perform the work of the other system, then stop the other system,
Instead, start it up with another functional task,
Business changes are being made intermittently. FIG. 1 is a block diagram showing a conventional dual system computer. In the example shown in Figure 1, while the computers are duplicated,
In normal times, it is used as a regular load balancing and standby redundant computer that performs other tasks on the standby system. In normal times, #1 computer 1 is in charge of online business, and #2 computer 2 is in charge of offline business. The #1 computer 1 exclusively uses each of the system common processing section 3a, the online business processing section 4a, the A input/output device 6, and the B input/output device 7, and the #2 computer 2 has the system common processing section 3b, the offline business processing section 5b, It exclusively uses the C input/output device 8. The offline business processing unit 5a and the online business processing unit 4b, which correspond to other businesses for each computer, are both in a dormant state. The mode selection switches 10 and 11 are used to determine whether each computer is to execute online or offline operations.
When it is set to the side, it is offline, and the system common processing units 3a and 3b are connected in either mode. In the configuration shown in Figure 1, processing operations (software)
Because the resources of the I/O devices and the resources of the I/O device group (hardware) are collectively managed, it is possible to monopolize the resources on both systems at the same time.
This is not allowed because it causes inconvenience, and in the case of two-way switching, it is necessary to first set the mode changeover switch 11 to neutral, then switch the mode switch 10 from A mode to B mode, and then switch the mode switch 11 to A mode. The reason for switching to each mode after releasing all functions is to avoid confusion in processing, but during this switching period,
It mainly supported the continuous processing of main system operations. In order to minimize interruptions when switching business processes, a shared memory (management memory) is placed between both computers, and various systems are used to confirm mutual operation status as the status of other systems and perform business switching. This method has also been tried. However, the installation of a common main memory or the installation of a shared auxiliary memory requires a dual (multiple) access device for the memory, and
The disadvantage is that the hardware configuration is quite expensive, such as duplicative installation for reliability reasons. SUMMARY OF THE INVENTION An object of the present invention is to provide a switching method for a dual-system computer that can switch modes in a dual-system computer without having a memory shared by both systems. The present invention switches input/output devices in advance so as not to interrupt the main business process, and mutually communicates the switching in order to minimize the input/output device switching incidental to the main business process. By doing so, the main business is not interrupted during the switchover. Specifically, an information exchange device is provided between both systems,
This is done by checking the sequential information of business and input/output device connections and releases in light of the sequence progress, and prevents the simultaneous use of input/output devices in duplicate systems.
In addition, the communication response confirmation time is mutually monitored for traffic jams, the transition step for business switching is mutually monitored, and business software that requires continuity is synchronized with the equipment switching in order to run continuously. It also manages the start and stop of business software, and in particular aims to ensure continuous processing of main online operations. FIG. 2 is a block diagram showing an embodiment of the present invention. In FIG. 2, #1 computer 1 and #2 computer 2 do not have shared memory and are installed independently from each other, with an information exchange device 14 for computer 1 and An information exchange device 15 for the computer 2 is connected to exchange control information between the own system and other systems. The input/output devices A16, B17, C18, D19 used in shared switching for both computers are the input/output bus switching devices A20, B21, C22, respectively.
The devices are configured so as to be connected to the dual input/output buses 12 and 13 via D23. Although the processing unit is not shown in FIG. 2, it is capable of processing similar to the configuration shown in FIG. 1, as well as online monitoring processing and processing.
Operation processing, data input processing, etc. are provided. Further, the mode switching command is automatically or manually issued to each bus line 12, 13 by the command device 24. This command device 24 has a built-in alarm circuit that displays the mode status and issues necessary warnings to the operator. Table 1 is a table that summarizes the processing in the configuration of FIG. 2 for each mode. Table 1 shows the case where computer 1 is the main system and computer 2 is the slave system.

[Table] In independent processing, if the main system and slave system are switched, the processing will also be switched, and other processing will not change in either mode. The information exchange devices 5 and 6 perform an exchange operation through system common processing of each computer. FIG. 3 is an operation time chart of an embodiment of the present invention. Before going into detailed explanation, the outline of the operation of the present invention will be compared with that of the conventional example, and the order of operation will be shown in a table as follows (the equipment is as shown in FIG. 1).

[Table] In FIG. 3, it is assumed that computer 1 is operating in A mode S4, computer 2 is operating in B mode S8, and mode switching is performed by mode switching signal S1. Here, only switching of shared devices will be explained. In particular, the computer processing mode is A mode S4 and S9, which are assigned online work where stagnation and interruption of work is not allowed.
On the other hand, B modes S5 and S8 are assigned offline operations that normally operate as backup systems. Switching of business processes when switching modes shall be in accordance with Table 2, and below, switching of input/output devices will be explained based on FIG. 3. In FIG. 3, the end signals CI1 and CI3 are transmitted from the computer 2 side to the computer 1 by the information exchange device 14.
The information exchange device 15 provides end signals CI2 and CI4 from the computer 1 side to the computer 2 side. Other processing, except for the mode display function,
It is executed in the management program in each computer. It is assumed that the alarm abort signal S26 is exchanged between the information exchange devices 14 and 15. The mode switching signal S1 provides an interrupt signal to the computers 1 and 2 simultaneously, either manually or automatically. Computer 1 starts #1 computer configuration management processing S3 by #1 computer interrupt determination S2, and prepares solutions for input/output equipment operating in A mode by #1 system first step completion S17. At the same time, #2 computer configuration management processing S7 is started, and the first step of #2 system is completed S.
18, prepares to stop the business operating in B mode and releases the connection of input/output equipment (OP1 state and OP2 state in Table 2), and #2B mode display S8
At the same time, the first step of #2 system is completed S13
The response is returned to the #1 system. #1 computer 1 starts #1 system configuration management processing S3 after interrupt determination S2,
#1 system 2nd step completed At S19, the connection of #1 system input/output equipment was released (OP3 state in the table), and A
While the mode is in operation, preparations are made to stop the work, the #1A mode display S4 is erased, and a response is returned to the #2 system as the completion of the second step S14 of the #1 system. After the interrupt determination S6, the #2 computer starts the #2 system configuration management process S7, and in the #2 system second step 20, the #2 system A
In addition to performing the operation tasks of the mode, connects the input/output equipment used in the A mode (OP6 state in the table), displays the #2A mode display S9, and sends a response to the #1 system as the second step of the #2 system is completed S15. Return to. At this point, the computers of both systems are in the #1 computer operation mode S10 while in the A mode actual operation S23.
#2 computer operation mode S11 switches from B mode actual operation S24 to A mode actual operation S23, and A mode operation spans both systems to maintain continuity.
Further, in response to the #2 system second step completion signal S15, the #1 computer starts the #1 system configuration management processing S3 after interrupt determination S2, and executes the #1 system third step S2.
1, A mode actual operation S23 is stopped, B mode actual operation S24 is started, input/output equipment used in B mode is connected, #1B mode display S5 is displayed, and #1 system 3rd step is started. As completion S16, the response #2 is returned. After the interrupt determination S6, the #2 computer starts the #2 system configuration management process S7,
In the third step S22 of the #2 system, it is recognized that the series of switching communication confirmations have been completed, and the process ends. During this time, the #1 configuration management process S3 and the #2 configuration management process S7 of both systems use the traffic congestion monitoring timer S25.
response from the other system (i.e., the first step of the #2 system is completed S13, the second step of the #1 system is completed S14,
Response signals from other systems such as the second step completion S15 of the #2 system and the third step completion S16 of the #1 system are monitored, and in the event of traffic congestion, a warning abort signal S26 is sent to other systems and mode switching is performed. Both systems mutually recognize that this does not hold. The input/output bus switching devices 20 to 23 are switched according to management processing instructions by a switching control device 25 connected to each computer. According to an embodiment of the present invention, various input/output devices shared in a dual-system computer are connected in each business operation mode in which the load is divided among the dual-system computers, with one side exclusively connected. In particular, even for input/output devices that are exclusively used for processing that does not allow interruption of business operations, when switching the business operation mode, the connection release and connection state of input/output devices are separated from the job switching. By communicating these, it is possible to prevent inconveniences caused by simultaneous use of input and output devices without interrupting business processing. As is clear from the above, according to the present invention, by mutually communicating the device connection and release states at the time of switching operation, switching can be performed without interrupting the processing of the main system. When switching input/output devices in advance so as not to interrupt the main business process, the third
There is no need for a processor for determining switching, and the configuration can therefore be simplified accordingly.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional dual system computer system, FIG. 2 is a block diagram showing an embodiment of the present invention, and FIG. 3 is an operation time chart of the embodiment of the present invention. 1...#1 calculator, 2...#2 calculator, 3a,
3b... Common processing unit, 4a, 4b... Online business processing unit, 5a, 5b... Offline business processing unit, 12, 13... Input/output bus, 14, 15...
Information exchange device, 16-19...Input/output device, 20
~23...I/O bus switching device, 24...Command device, 25...Switching control device.

Claims (1)

[Scope of Claims] 1. Two processing devices each having a common processing section and a business processing section and formed of a dual system of a main system and a slave system, and an input/output bus for both processing devices. an input/output device shared by the processing devices of both systems via an input/output bus switching device connected to the dual system computer system for load-sharing operation of automatic processing operations, comprising: An information exchange device provided between the two processing devices exchanges control information of both processing devices and operation information including the connection state of the input/output equipment, and an information exchange device provided between the two processing devices provides switching between the processing devices. A switching control device that performs switching control based on a command causes the input/output bus switching device to switch the input/output bus switching device prior to switching the business processing units of the two processing devices based on the operation information from the information exchange device when switching the processing device. A switching method for a dual-system computer, characterized in that, after all input/output devices connected to the dual-system processing devices are released via a switch, the input/output devices are connected to the switching destination slave processing device side.