JPH10164060A - Monitoring system in data communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continue communication between a monitoring device and a module to be monitored without interruption and to improve the reliability of a network without disabling monitoring and control from the monitoring device by automatically switching a master module to be monitored when a fault occurs in the master module to be monitored. SOLUTION: Respective modules A2-E6 can be set to the master modules to be monitored and slave modules to be monitored. When a module A2 is set to the master module to be monitored, the modules B3-E6 become the slave modules to be monitored. The module A2 sets a monitoring path 7 for the monitoring device 1 and transmits monitor information and receives control information. Transmission right for health-checking the module A2 is sequentially and endlessly succeeded among the modules B3-E6. Thus, the monitoring control of the module which does not become the fault can be continued until all the modules become the faults.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a monitoring system for a data communication device in a data communication network in which a plurality of modules are connected by a LAN, a bus or the like.

When monitoring and controlling a plurality of modules connected by a LAN, a bus, or the like, it is desirable that the monitoring device sets all modules and logical paths. May not be able to be set. In such a case, one of the plurality of modules sets a monitoring device and a logical path on behalf of the module, and the module sets a path with the remaining modules to indirectly transmit and receive monitoring information. Will be. However, when a module connected to the monitoring device becomes a failure, communication of monitoring information cannot be performed.

[0003]

2. Description of the Related Art FIG. 12 is an explanatory view of a conventional example. FIG.
Is a configuration example of a conventional data communication network. In the figure, 90 is a plurality of data communication devices A to D, 91 is a terminal such as a personal computer connected to the data communication device 90 by a line, and 92 is each data device. A host for data processing and data transmission / reception connected to the data communication device; a communication path such as a LAN or a bus connecting the data communication devices;
Reference numeral 94 denotes a monitoring device for remotely monitoring the states of a plurality of data communication devices, and reference numeral 95 denotes a communication path for connecting with the data communication device 90.

[0004] The data communication device 90 communicates with each terminal 91 connected to a line between another terminal in the same data communication device 90 or a terminal of another data communication device via a communication path 93. And provides a data communication service, and a terminal connects to the host 92 to provide data processing and exchange services.

The monitoring device 94 is provided at a location remote from the installation position of the modules A to D in order to monitor the status of each of the data communication devices 90 (hereinafter, referred to as monitored modules) A to D. The following is a conventional monitoring control method in such a configuration.

One of the monitored modules A to D is configured as a monitored parent module (for example, module A), and the other module is configured as a monitored child module (modules B to D). The monitored parent control function in the monitored parent module A transmits / receives monitoring information to / from the monitored monitoring functions in the other monitored child modules B to D via the communication path 93, and transmits the monitored information. The monitored module A aggregates the monitoring information and transmits the monitoring information to the remote monitoring device 94 via the communication path 95. In this case, a communication path 95 is provided between the monitoring device 94 and the monitored parent module A.
Is provided.

The above method has a problem that if a failure occurs in the monitored parent module A, the entire data communication network cannot be monitored. As a means for avoiding this, there is a method of switching the monitored parent module from the monitoring device.

In the case where the monitoring device cannot specify one of the monitored parent modules as in the above method (the monitoring device and the monitored module do not have a mechanism for switching from a remote monitoring device) Case). In this case, two monitored parent modules are provided, and a main monitored parent module (for example, module A in FIG. 12) and a sub-monitored parent module (module B in FIG. 12).
The sub-monitored parent module constantly monitors the main monitored parent module. Normally, the main monitored parent module collects monitoring information from other modules, and if the main monitored parent module fails, the sub-monitored parent module There is a method in which the monitored parent module detects a failure, transmits and receives monitoring information to and from the monitored child module in place of the main monitored parent module, and transmits and receives the aggregated monitoring information to and from the monitoring device.

[0009]

In the above case, if both the main monitored parent module and the sub-monitored parent module fail, there is a problem that the monitoring control of the data communication network becomes impossible. .

According to the present invention, when the switching control of the monitored parent module cannot be performed from the monitoring device as described above,
One or two monitored parent modules fail,
This solves the problem that the entire data communication network cannot be monitored and controlled. The data communication network can continue monitoring and controlling modules that are not in trouble until all the modules that make up the data communication network fail. The purpose of the present invention is to provide a monitoring method.

[0011]

FIG. 1 is a diagram showing the principle of the present invention, and FIG. 2 is a diagram showing the structure of a table. In FIG. 1, 1 is a remote monitoring device, and 2 to 6 are data communication devices (denoted by modules A to E) which configure a data communication network connected to a terminal (not shown) or a host (not shown) by a line, respectively. , 7 are monitoring paths (communication paths used for monitoring) for communicating between the monitoring device 1 and the current monitored parent module, and 8 is an LA connecting the modules.
This is a communication path composed of N or a bus. Note that a logical path 7 'is always set between the monitoring device 1 and each of the modules A to E as indicated by a dotted line. The logical path is a path in a state where the path to the monitoring device can be activated at any time.

In the present invention, any module can be a monitored parent module. In the example of FIG. 1, when module 2 (module A) is first set as the monitored parent module, the other modules 3 to 6 (module B to E) are monitored child modules. The monitored parent module A sets a monitoring path 7 indicated by a solid line to the monitoring device 1 by the path setting means 2c using the logical path 7 and communicates with the monitoring device 1 to transmit monitoring information and receive control information. I do. Further, the monitored parent module A receives the health check (inquiry of the module device and line status) transmitted from the monitored child module having the health check transmission right, and indicates the status (normal or abnormal). The response is transmitted by the health check reception monitoring means 2a, and the monitored child module having the right to transmit the health check is abnormal if the time is monitored and the next health check is not received within a predetermined time from the reception of the previous health check. Then, the health check transmission right possession module determination notifying unit 2b is activated, and the health check transmission right possession module determination notification unit 2b determines the health check transmission right possession module as another monitored module and performs notification.

The transmission right to check the health of the monitored parent module is successively endlessly inherited between the monitored child modules without being fixed to a specific monitored child module. Each of the modules A to E has a table shown in FIG. 2 in which all modules are registered, and the status of the data communication network is grasped from the table.

In the table of FIG. 2, among the modules A to E shown in FIG. 1, a current monitored parent module, a faulty module, and a module having a transmission right are set.

First, when the module B has the right to transmit the health check, the health check transmission / reception means 3a transmits a health check to the monitored parent module A, and when a normal response is returned, the health check transmission right transfer notifying means 3b. Notifies the next monitored child module C registered in the table of the transfer of the health check transmission right, and sets a module having the transmission right when the response of the transmission right transfer acknowledgment is returned from the next monitored child module C. The module transmits the updated table to other modules, and each module updates its own table according to its contents and changes the state to the state shown in the table to execute processing such as transmission of a health check. Parent module A monitored by health check
If the response from the server is abnormal or no response is returned, the monitored parent module A is determined to be faulty, the monitored parent module parent determination notifying means 3c is activated, and the next module is determined as the monitored parent module. The table in which the contents are set is notified to another module.

The monitored parent module 2 (including the monitored parent module to be changed) communicates with the monitoring device 1 via the monitoring path 7 to send the network management information of each module constituting the data communication network to the monitoring device 1. connect.

As described above, since each of the modules A to E is operated as both the monitored parent module and the monitored child module, each of the modules A to E operates as a module provided in the module A and a module B provided in the module B in FIG. Has both.

[0018]

FIG. 3 shows the configuration of an embodiment of a data communication device (module). In FIG. 3, 10 is a data communication device (module), 11 is a line corresponding unit that accommodates a line connected to a plurality of terminals (and a remote monitoring device),
Reference numeral 12 denotes a transmission / reception control unit for transmitting and receiving a table and frames of data and the like to other modules in the data communication network via Ethernet (TCP / IP), and 13 stores a table (see FIG. 2) and software. A central processing unit for updating a table, generating a command / response of a frame, managing a timer, and moving a transmission right of a health check;
Denotes a monitored function control unit which controls communication with the monitoring device and is driven only by the monitored parent module, and 16 denotes an Ethernet LAN.

FIG. 4 shows the configuration of the format of a frame communicated between modules. This frame format corresponds to TCP / IP, but has a command / response portion provided in a user data field. That is, a MAC (Medium Access Control) header is placed at the top, an IP (Internet Protocol) header is placed next, and a "command / response section" according to the present invention is provided in the user data field thereafter, followed by "data" and finally an error check. FCS (Frame Check Sequence).

The command / response portion is represented by a 2-byte code. As shown in detail in FIG. 4, the command is "health check" (code 01), the response is "normal response" (code 02), and the "abnormal response" (Code 0
3), "Response reception completed" (code 04), "Transmission right transfer request" (code 05) as command, "transmission right transfer acknowledged" (code 06) as response, and "table transmission" (code 07) ) To transmit the table data. In the case of an abnormal response, the cause and the diagnostic code are returned as data. The user data is represented by a code 08. The module receiving the frame determines the control operation by looking at the code of the command / response section. For example, if the command / response part is 01
The module that receives the frame activates a health check application. The health check inquires about the current device status / line status of the module.

FIG. 5 shows a configuration of mapping of a table on a memory, and shows an example in which five modules A to E are provided. The first four bytes of the table (columns represented by 0 to 7 at the top of the table) indicate the IP address of each module, and the subsequent one bit (column represented by 8 at the top of the table) indicates the parent module (monitored parent module) , The next one bit (the column indicated by 9 at the top of the table) is a flag indicating a module which is a fault ("1" indicates a fault and "0" indicates normal), and the next one bit (a table in the table). The upper 10 column indicates a module having a transmission right ("1" indicates transmission right), and the remaining 3 bits (the upper 11 to 13 columns in the table) can be used for other purposes. It is. Each module has the table shown in FIG. 5, and when another module transmits the latest table, it is received by each of the other modules and rewrites the table in each memory. When a failure is detected, the table is updated and transmitted to another module.

FIG. 6 shows a configuration example of a data communication network to which the present invention is applied. In this configuration, modules A to E having the configuration shown in FIG. The monitored parent module (to be referred to as module A) communicates with the monitoring device and transmits network management information of each module constituting the data communication network to the monitoring device. A monitoring path is always established between the monitoring device and the monitored parent module.

FIG. 7 shows the transmission / reception operation between the monitoring device and the monitored parent module. The monitoring device periodically sends an inquiry about the device status (the period is X) to the monitored parent module. Done using The monitored parent module that has received the inquiry transmits a response to the monitoring device using the monitoring path. The monitoring path is used by setting a logical path for monitoring, and is used only by the monitored parent module. When it becomes necessary to notify the monitoring device of a failure or a change in configuration in the data communication network, the content is asynchronously transmitted to the monitoring device as an autonomous message. A logical path is set between the other monitored child module and the monitoring device, but setting as a monitoring path (a communication path using the logical path) is performed until the monitored module becomes a monitored parent module. Absent.

FIG. 8 shows an operation sequence according to the present invention, and shows a part of an operation sequence of a monitoring operation between modules in the configuration example shown in FIG. First, the module A is the monitored parent module, and the module B is the health check transmission right possessing module. Description will be made below in the order of.

A health check is transmitted from module B to module A. A response is transmitted from module A to module B. Module B notifies module A of the completion of the response. As a result, the health check is completed, and thereafter, the process moves to the transfer of the health check transmission right.

The request for transferring the health check transmission right is transmitted from the module B to the module C. The module C sends a health check transmission right transfer acknowledgement to the module B.

A health check is transmitted from module C to module A. A response is transmitted from module A to module C. Module C notifies module A of the completion of the response reception. As a result, the health check is completed, and thereafter, the process moves to the transfer of the health check transmission right.

After that, although not shown in FIG. 8, when the normal operation is performed, the transmission right is transferred to the module D, and the transmission right is transferred to the module E through the same sequence as described above. After E, the transmission right returns to module B.

Module A as a monitored parent module
As shown in FIG. 8, when a health check from each module is received (in FIG. 8), the timer is started, and when the next health check is received within the time set in the timer, the timer is reset, and Restarts, but if a health check is not received within a predetermined time, the timer is not reset and a time-over output is generated,
Processing for detecting that a failure has occurred in a module having a transmission right (either the source or destination of the transmission right) and corresponding processing (see FIG. 10 described later).

FIG. 9 shows the operation of the failure detection by the monitored child module. In the operation sequence of FIG. 8, when the module B transmits a health check to the module A (monitored parent module), no response is returned from the module A within a preset time. In this case, module A is set as an abnormal status (failure state) in the table shown in FIG. 5 to indicate that module A has a failure, and the table is transmitted to another module and recognized by the other module. In this case, the monitored parent module moves by processing of the monitored child module described later (see FIG. 11 described later).

FIG. Is a case where the transmission right transfer request is transmitted, and the response of the transmission right transfer acknowledgment is not returned within the time set by the partner module. In the example shown in the figure, since no response is returned from the module C to which the transmission right has been transferred, the module B detects that a failure has occurred in the module C and performs processing such as setting in a table (see FIG. 11 described later).

FIG. 10 shows the processing flow of the monitored parent module. Each module has this processing function and executes this processing when it is determined from the table that the module itself has become the monitored parent module.

When the monitored parent module receives a health check from another monitored child module (S 10 in FIG. 10).
1) The device status and line status of the own module are transmitted as a response (S2). At the same time, the timer is started (S3), the reception of the next health check is periodically determined (S4), and if it is received, a response is transmitted in step S2. If the time has not expired, the process returns to step S4 to further wait for a health check. If a timeout occurs, the module to be monitored that has the transmission right is recognized as abnormal, the failed module in the table (see FIG. 5) is marked, and the module that has the health check transmission right is set to the next module. The table is transferred to all modules, and a failure is notified. Note that FIG.
Although not shown in the figure, after transmitting the response of the health check, the completion of the health check is received by receiving the reception completion of the response from the module. Further, the sequencer processing shown in FIG. 7 is executed for the monitoring device.

FIG. 11 is a processing flow of the monitored child module having the health check transmission right. Each module has this processing function, and executes this processing when the module itself becomes the monitored module having the health check transmission right according to the table.

In response to the request to move the health check transmission right from the previous module, the monitored child module that has transmitted the move acknowledgement transmits a health check to the monitored parent module (S1 in FIG. 11). On the other hand, it is determined whether a normal response has been received from the monitored parent module (S2), and if the response is normal, a response completion is transmitted to the monitored parent module (S3). If a normal response cannot be received (no response for a fixed time or a response indicating an abnormal state), the monitored parent module is marked as a failure on the table (see FIG.
4), the change of the monitored parent module is performed by marking the table (the monitored child module adjacent to the current monitored parent module is set as the monitored parent module);
The table is transmitted to another module (S5).

Following the above step S3 or S5,
The transmission right transfer request of the health check is transmitted to the next module (S6 in FIG. 11). It is determined whether an acknowledgment for this transfer request has been received within a predetermined time (S7). If not, it is determined that an error has occurred in an adjacent module, the module is marked as faulty on the table, and the table is transferred to all modules. To notify the failure (S
8). Thereafter, the process returns to step S6, and transmits a request to move the health check transmission right to the module registered next to the module. In addition, when the transfer approval is received, the table is transmitted to all the modules as the next module having the right to transmit the health check (FIG. 1).
1 S9).

When a failure occurs in a plurality of modules, the transfer of the health check transmission right is continued until a normal module is found, but the monitored parent module and the health check transmission right possession module simultaneously fail. Only when this happens, switching of the modules becomes impossible, but in the case of a data communication network composed of a large number of modules, the probability of such occurrences is extremely low.

[0038]

According to the present invention, in a data communication network in which a plurality of modules are connected by a LAN, a bus or the like, monitoring is performed by automatically switching the monitored parent module when a failure occurs in the monitored parent module. Communication between the device and the module to be monitored can be continued without interruption, monitoring and control from the monitoring device will not be disabled, and the network will be monitored by grasping the situation at the time of failure and continuing monitoring of other normal modules. Reliability can be improved.

If the probability of one module becoming a fault is α, the probability of being unmonitored by the conventional method of monitoring by a monitored module is α ² , but according to the present invention, the number of modules is N The probability that the entire data communication network becomes an obstacle = (α ² ) / (N−1). Therefore, the failure occurrence probability of the data communication network of the present invention decreases as the number of modules increases, and the reliability improves.

[Brief description of the drawings]

FIG. 1 is a principle configuration diagram of the present invention.

FIG. 2 is a diagram showing a configuration of a table.

FIG. 3 is a diagram illustrating a configuration of an embodiment of a data communication device (module).

FIG. 4 is a diagram showing a configuration of a format of a frame communicated between modules.

FIG. 5 is a diagram showing a configuration of mapping of a table on a memory.

FIG. 6 is a diagram showing a configuration example of a data communication network to which the present invention is applied.

FIG. 7 is a diagram illustrating an operation of transmission and reception between a monitoring device and a monitored parent module.

FIG. 8 is a diagram showing an operation sequence according to the present invention.

FIG. 9 is a diagram showing an operation of failure detection by a monitored child module.

FIG. 10 is a diagram showing a processing flow of a monitored parent module.

FIG. 11 is a diagram showing a processing flow of a monitored child module having a health check transmission right.

FIG. 12 is an explanatory diagram of a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Monitoring device 2-6 Data communication device (module AE) 2a Health check reception monitoring means 2b Health check transmission right possession module determination notification means 3a Health check transmission / reception means 3b Health check transmission right transfer notification means 3c Monitoring parent module determination Notification means 7 Monitoring path 7 'Logical path 8 Communication path

Claims (4)

[Claims] 1. A monitoring method for monitoring a plurality of monitored modules constituting a data communication network by a monitoring device provided at a remote place, comprising a communication means between the monitoring device and the plurality of monitored modules. The plurality of monitored modules include means for communicating with each other via a communication path, wherein one of the monitored modules is a monitored parent module, another monitored module is a monitored module, and one of the monitored modules is a monitored module. One module is set as a health check transmission right possessing module, and the health check transmission right possessing module transmits a health check to the monitored parent module and checks a response, and another monitored module receives a normal or abnormal response. Means for informing one of the child modules of the transfer of the health check transmission right; Means for determining the next monitored parent module when an abnormality is detected in response to the lock and notifying all other modules, and the monitored parent module performs a response indicating a state upon receiving a health check, and Means for monitoring that a health check is received within a set time since the last health check reception, and means for determining a health check transmission right possession module and notifying another module if the health check is not received within the set time. A monitoring method in a data communication device, comprising: 2. The monitoring method according to claim 1, wherein said monitored module comprises means for setting a logical path to said monitoring device when the monitored module becomes a monitored parent module. 3. The monitored parent module and the monitored child module according to claim 1, wherein the monitored parent module and the monitored child module each include a table indicating a current parent module and a current transmission right possessing module for all the modules. The notification of the ownership determination of the health check transmission right from the parent module The notification of the transfer of the health check transmission right from the monitored child module and the notification of the determination of the monitored parent module are set in the table with the changed contents, A monitoring method in a data communication device, wherein the monitoring method is performed by transmitting to a module. 4. The module according to claim 1, wherein the health check transmission right possessing module transmits a health check to the monitored parent module and, after receiving a response, transmits the health check to the monitored child module in the next order. Transmitting a health check transmission right transfer request and receiving a response from the next monitored module that acknowledges the transfer of the health check transmission right to complete the transfer of the transmission right. Monitoring method.