JPH086887A - Server connection switching method - Google Patents

Abstract

PURPOSE:To improve the performance of a client server system by efficiently performing the server connection switching of the system. CONSTITUTION:At the time of the switching of a server 131 of the client server system, a server (backup server 120) at a switching destination informs clients 141 and 142, previously selected and specified among respective clients 141-143, of switching indication information including the connection destination address of the switching-destination server (backup server 120) (backup reports 340 and 350) to indicate the switching of the server, and the clients 141 and 142 having received the switching indication information switch a previously set origination destination from the server 131 at the switching source to the server (backup server 120) at the switching destination on the basis of the connection destination address.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a server backup technology in a client / server system, and more particularly to a server for controlling connection between a mainframe and a client in an online system configuration for performing main business processing on the mainframe. The present invention relates to a server connection switching method suitable for efficiently performing backup of the above according to the operation of the system.

[0002]

2. Description of the Related Art Conventionally, in an online system, a mainframe, a disperser, and a terminal are generally connected by a line.
AN (Run / Local Area Network,
There is a tendency to shift to a configuration in which a server or client on the local information network is replaced. In this configuration, there is one server and many clients on the LAN, and the server and the mainframe are connected by a line. For example, if there are a plurality of bases such as a branch office, the base has one LAN, the server of each LAN is connected to the mainframe,
The client is connected to the mainframe via the server. In this system, main tasks are processed in the mainframe, so the server mainly relays messages between the client and the mainframe. As described above, all the messages addressed to the mainframe go through the server, so that if the server is stopped due to a failure or the like, the work is completely disabled.
For this reason, a spare server is prepared, and when the original server is stopped, the spare server on the backup side is switched to.

Generally, in a client / server system, the client side provides a transaction trigger, and the server waits for it. Therefore, switching of the connection between the client and the server is performed, for example, in Japanese Patent Laid-Open No. 2-13
It is performed as described in Japanese Patent No. 5550. That is, if the server “downs” and the workstation (client) does not succeed after logging on for about 6 times, the workstation logs on to the backup server instead.

However, in such a conventional technique, since switching to the backup server is performed from the client side, each client is previously provided with information (connection destination address) for connecting to the backup server. You have to register. Therefore, if a new backup server is provided for the purpose of improving the operational efficiency of the system, etc., if the backup server connection destination address is new, all registered contents of each client must be changed. I won't. Also, for example, when the number of clients requesting connection with the mainframe increases and the load on the server increases, the backup server processes connection requests from some clients to improve system operation efficiency. Although it is effective to improve, in the conventional technique, the client side repeats logon about six times before switching the connection destination, so that the communication traffic from each client to the server increases and the response speed of the system increases. It becomes slow and system performance deteriorates.

[0005]

The problem to be solved is that, in the conventional technology, the client side controls the switching to the switching destination server such as the backup server, which causes a change in the operating mode of the system. This is a point that cannot be dealt with easily. An object of the present invention is to provide a server connection switching method that solves the problems of the conventional techniques and can improve the performance of a client / server system that constitutes an online system that performs main business processing on a mainframe. That is.

[0006]

In order to achieve the above object, the server connection switching method of the present invention is such that, at the time of switching the connection of the server, each client 14 is switched from the switching destination server 131.
1 to 143, the switching instruction information including the connection destination address of the switching destination server (backup server 120) is notified to the clients 141 and 142 that are selected and designated in advance (backup notification 340, 350). The clients 141 and 142 that have instructed the switching and received the notification of the switching instruction information, based on the connection destination address,
It is characterized in that the preset call destination is switched from the switching source server 131 to the switching destination server (backup server 120).

[0007]

In the present invention, the client switches the connection of the server according to an instruction from the switching destination server such as the backup server. In other words, the client side should always be able to accept outgoing calls from the switching destination server, and the switching destination server should connect its own device to each preregistered client when the server goes down. A message instructing switching of the connection destination including the destination address is notified. Then, the client receiving this message switches the connection of the server. As a result, only these specific clients can log on to the switching destination server. In this way, since the connection switching of the server is made to selectively perform only a specific client,
For example, in an online system in which main tasks are processed by a mainframe and a message is mainly relayed between a client and a mainframe, a load can be distributed to a plurality of servers. Further, when installing a new server having a different connection destination address, the connection destination information on each client side can be automatically changed from the newly installed server. Further, by registering all the clients in advance, it is possible to cope with connection switching to the backup server when the main server goes down.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a sequence diagram showing an embodiment of the processing operation of a client / server system according to the server connection switching method of the present invention, and FIG. 2 is an example of the configuration of a client / server system that performs the server connection switching processing. It is a block diagram shown. As shown in FIG. 2, in the client / server system of this example, the mainframe 1
Below 10 is a backup server 120 and servers 131 and 132 of each sales office.
In the LAN 151, 152, the client 1
41 to 143 and clients 144 to 146 are connected. In addition, the backup server 120
ISDN160 (Integrated Serv)
LANs 151 of each sales office, via the Ices Digital Network, integrated digital communication network, etc.
It is connected to 152. Furthermore, LAN 151, 15
2 is connected to the ISDN 160 via the routers 151a and 152a, and the backup server 120 is connected to the ISDN 160 via the router 120a.

Each of the clients 141 to 146 is always
A call from the backup server 120 can be accepted. Then, for example, LAN 151, 1
When the servers 131 and 132 on the server 52 stop functioning or are overloaded, the backup server 120 uses the router 120a.
And each client 141 via ISDN 160
To 146 or to a client selected and designated in advance, a message (switching instruction information) 200 including an IP address (connection address of the backup server) 230 is sent to switch the server, as shown in FIG. Instruct. The clients 141 to 146 receiving the message 200 shown in FIG.
Based on 0, the preset servers 131, 132
The call destination is switched to the backup server 120.

In this way, each client 141-
146 switches the connection destination server according to an instruction from the backup server 120. Therefore, it becomes possible for the backup server 120 side to notify only the specific client of the switching instruction of the connection destination server, and only these specific clients can notify the backup server 120.
You can log on to. As a result, the connection destination of each of the clients 141 to 146 can be distributed to the servers 131 and 132 and the backup server 120 when the server 131 or 132 is overloaded, not when the server 131 or 132 is down. , Each client 14
The relay processing load of messages between 1 to 146 and the mainframe can be distributed among the servers 131 and 132 and the backup server 120. Further, when a new server or a backup server is provided for the purpose of changing the operation mode of the system or improving the performance, even if the IP addresses of these servers differ, the connection destination of each client 141-146 side Information can be changed automatically.

FIG. 3 is an explanatory diagram showing an example of a backup notification message format transmitted to the client. The message 200 includes a header 210 in which information such as protocol and business-specific information is registered, a backup notification 220 in which information indicating that this message is for backup notification is registered according to the present invention, and a network of backup servers. Information indicating the above address, such as Ethernet (developed jointly by Xerox Corporation, Digital Equipment Corporation (DEC), and Intel Corporation, 19
IP in the bus structure LAN that was commercialized in 1980)
It is composed of an IP address 230 in which the address is registered.

The processing operation according to the present invention when the server 131 in FIG. 2 is stopped will be described below with reference to FIG. First, when server stop 310 occurs, mainframe 1
In FIG. 10, by detecting the line disconnection 320, it is possible to know which office server has a failure. Next, the mainframe 110 instructs the backup server 120 to back up the failed sales office (backup instruction 330). Based on this instruction, the backup server 120 activates the program for transmitting the message 200 shown in FIG. 3, and notifies the pre-designated clients 141 and 142 of the backup notification 340,
Perform 350. The clients 141 and 142 have activated a program waiting for the reception of the backup notification message from the backup server 120, and the backup notification 34 from the backup server 120 has been activated.
Receive message 0,350. Upon receiving this message, the clients 141 and 142 confirm that this message (backup notification 340, 350) is this backup notification by the information of the backup notification 220 in the message 200 of FIG. Looking at 230, the transmission destination of the subsequent business process is switched.

As described above with reference to FIGS. 1 to 3, in the server connection switching method of this embodiment, each client is always in a state of accepting a call from the backup server. Then, when the server is stopped or the like, the backup server sends a backup notification message to the clients under the server, and instructs each client to switch the server connection. Each client switches the connection destination to the spare server based on the received message.

As described above, since each client switches the connection destination server according to the instruction from the backup server, the backup server side notifies only the specific client of the connection destination server switching instruction. ,
Only specific clients can log on to the backup server. As a result, when the server is overloaded, the connection destination of each client can be distributed to the server and the backup server to distribute the load. In addition, when a new server or backup server is installed for the purpose of changing the system operation mode or improving performance, even if the IP addresses of these servers differ, the connection destination information on each client side is automatically It is possible to easily change the system operation easily and efficiently.

The present invention is not limited to the embodiments described with reference to FIGS. 1 to 3, and various modifications can be made without departing from the scope of the invention. For example, in this embodiment, the backup server is the switching destination server, but the switching destination server may be a newly provided server. Also, the connection switching between the server and the backup server in the online system that controls the connection between the mainframe that performs main business processing and the client has been described as an example, but a client that consists of only one server and multiple clients It can also be applied to a server system. It is also possible to instruct all clients to switch the connection from the server to the backup server, and switch the servers not only to a specific client but to all clients.

[0016]

According to the present invention, the connection destination address registered in each client is changed and the connection between the client and the server is switched according to an instruction from the switching destination server. Since unnecessary connection confirmation from each client to the server does not occur, increase in communication traffic can be avoided, it is possible to prevent system performance deterioration due to delay in system response speed, and server connection switching. Can be selectively performed only by specific clients, the load can be distributed to multiple servers, and even when a server with a new connection destination address is provided, it can be easily handled. It is possible to efficiently improve the operation efficiency of the system by installing a new server.

[Brief description of drawings]

FIG. 1 is a sequence diagram showing an example of a processing operation of a client / server system according to a server connection switching method of the present invention.

FIG. 2 is a block diagram showing a configuration example of a client / server system that performs a server connection switching process according to the present invention.

FIG. 3 is an explanatory diagram illustrating an example of a backup notification message format transmitted to a client.

[Explanation of symbols]

 110 mainframe 120 backup server 120a, 151a, 152a router 131, 132 server 151, 152 LAN 141-146 client 160 ISDN 200 message 210 header 220 backup notification 230 IP address 310 server stop 320 line disconnection 330 backup instruction 340, 350 backup notification

Claims (1)

[Claims] 1. A method for switching connection of a server in a client / server system, wherein when switching the connection of the server, the server of the switching destination switches to the client selected and designated in advance among the clients. The switching instruction information including the connection destination address of the server, the switching instruction of the server is instructed, and the client receiving the notification of the switching instruction information switches the preset call destination based on the connection destination address. A server connection switching method, characterized in that the server is switched from the server to the switching destination server.