JP2937871B2 - Polling monitoring method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polling system for monitoring the presence or absence of a response from a plurality of monitored devices by a monitoring device, and transmitting an error report for the monitored device having no response from the monitoring device to a higher-level device. Related to monitoring method.

[0002]

2. Description of the Related Art Japanese Patent Laid-Open Publication No. 3-296349 discloses the following monitoring method. First, the control station (monitoring station) polls the subordinate station (monitored station),
Thereby, each dependent station confirms whether or not its own station has been selected. Subsequently, the dependent station, which has been selected as its own station, makes a transmission request to the control station, which is the partner station. Next, the dependent station checks whether or not there is transmission data, and if so, waits for transmission permission from the control station, and transmits text when transmission is possible. On the other hand, if it is determined that there is no transmission data, it waits for transmission permission from the control station.
Transmit the transmission end code. If transmission is not possible due to the down of the control station, it is determined that a failure has occurred and abnormal processing is performed. In this case, by estimating the response time of the partner station, it is determined that the partner station has failed when the predicted time has elapsed.

[0003]

However, in this prior art, when the monitored station (dependent station) is not connected to the monitoring station (control station), a response to polling cannot be received. Has a problem that an error report is erroneously recognized as having occurred on a monitored device or a line, and an unnecessary error report is transmitted to a higher-level device.

An object of the present invention is to prevent transmission of such an unnecessary error report when the monitored station is not connected to the monitoring station.

[0005]

According to the present invention, a table for storing the presence or absence of connection of each monitored device is provided in the storage unit of the monitoring device for each connection position number of the monitored device.

The monitoring device periodically transmits a status request as polling to the monitored device, and activates an individual timer for each monitored device at the time of transmission. The monitored device transmits a status report as a response when receiving the status request from the monitoring device, and specifies a table corresponding to its own connection position number at that time. For the monitored device that has received the status report, the monitoring device sets connection to the table corresponding to the connection position number designated by the monitored device, and stops the timer corresponding to the monitored device. For a monitored device that has not responded to the status report, the time-out of the timer corresponding to the monitored device is regarded as a response non-reception, and the table corresponding to the connection position number of the monitored device is referred to. If the contents are connected, an error report is transmitted to the host device via the line, but if there is no connection, no error report is made.

[0007]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a system configuration for realizing a monitoring method according to the present invention. This system is
A plurality of monitored devices 2 are connected to the
The monitoring device 1 is connected to a host device 4 via a line 5. The monitoring device 1 includes a storage unit 7 in addition to the control unit 6.

As shown in FIG. 2, the storage unit 7 has the same number of tables 8 as the maximum number n connectable to the monitored device 2.
Are prepared, and the arrangement corresponds to the connection position of the monitored device 2. That is, the first table corresponds to the monitored device having the connection position number 1, the second table corresponds to the monitored device having the connection position number 2, and so on.
The third table corresponds to the monitored device with the connection position number n. Then, each monitored device 2 specifies a table corresponding to its own connection position number when reporting a status in response to a status request from the monitoring device 1. The monitoring device 1 that has received the status report refers to the specified connection position number and determines whether or not the corresponding table has a connection status (connected or not connected).
Set. The initial value is set to no connection (not connected).

The monitoring device 1 periodically transmits a status request as polling to the monitored device 2 via the line 3 and activates an individual timer for each monitored device 2 at the time of transmission.
Upon receiving the status request from the monitoring device 1, the monitored device 2 transmits a status report as a response, and specifies the table 8 corresponding to its own connection position number at that time. The monitoring device 1
Regarding the monitored device 2 that has received the status report, the connection status (with connection) is set in the table 8 corresponding to the connection position number of the monitored device 2, and the monitored device 2 is also supported. Stop the timer. Therefore, the timer of the monitored device 2 that has received the status report response does not time out.

On the other hand, the monitored device 2 having no response to the status report
Regarding the above, when the timer corresponding to the monitored device 2 has timed out, the response is not received, and as a result of referring to the table 8 corresponding to the connection position number of the monitored device 2, the monitored device 2 is connected. In this case, an error report is transmitted to the host device 4 via the line 5, but if no connection is made, no error report is made.

FIG. 3 is a flowchart showing the operation of the monitoring apparatus 1 at the time of polling. In the figure, the monitoring device 1 transmits a status request to the monitored device 2 (step S1), and then waits for reception of a status report for a predetermined time (time set by a timer) (step S2). If received (YES in step S3), the fact that the monitored device 2 is connected is stored in the table 8 as described above (step S4). When the status report has not been received (NO in step S3), it is determined whether or not the monitored device 2 is connected with reference to the table 8 of the monitored device 2 (step S5), and the monitoring device 2 is connected. If
An error report is transmitted to the host device 4 (step S
6). If not connected (not connected), no error report is sent.

FIG. 4 is a sequence diagram showing the operation according to the present invention. If the status report has not been received in response to the status request from the start of the system until the monitoring device 1 receives the first status report from the monitored device 2, the monitoring device 2 recognizes that the monitored device 2 is not connected. , The monitored device 2 recognizes that it is not connected, and does not report an error to the host device 4. Thereafter, when the monitored device 2 is connected and receives a status request,
The monitoring device 1 starts the monitoring process. If a status report for a subsequent status request has not been received, the monitoring device 1 recognizes that an abnormality has occurred in the monitored device 2 or the line 3 and reports an error to the host device 4.

[0014]

As described above, the monitoring method of the present invention stores the presence / absence of connection of each monitored device based on the result of monitoring the first response from the monitored device to polling. The storage contents are referred to at the next polling, and if the monitored device is connected and the monitoring result is not responding, an error report for the monitored device is transmitted to the higher-level device, and the stored contents are not connected. Since the error report is not transmitted when the monitoring result is no response, unnecessary transmission of the error report when the monitored device is not connected can be omitted.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a system for realizing a monitoring method according to the present invention.

FIG. 2 is a table configuration diagram of a storage unit of the monitoring device shown in FIG.

FIG. 3 is a flowchart illustrating an operation of the monitoring device at the time of polling.

FIG. 4 is a sequence diagram showing the operation of the monitoring method according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 monitoring device 2 monitored device 3 line between monitoring device and monitored device 4 host device 5 line between monitoring device and host device 6 control unit 7 storage unit 8 table

Claims (1)

(57) [Claims] 1. A polling-type monitoring method for monitoring presence / absence of a response from a plurality of monitored devices by a monitoring device, and transmitting an error report for the monitored device having no response from the monitoring device to a higher-level device. In the storage unit of the monitoring device, a table for storing the presence or absence of connection of each monitored device is provided for each connection position number of the monitored device, and the monitoring device periodically sends a status request to the monitored device as polling. And starts an individual timer for each monitored device at the time of transmission. When the monitored device receives a status request from the monitoring device, it sends a status report as a response and responds to its own connection position number. For the monitored device that has received the status report, the monitoring device sets connection to the table corresponding to the connection position number specified by the monitored device, and sets the monitored Stop the timer corresponding to the device so as not to time out, and for the monitored device that has not responded to the status report, when the timer corresponding to the monitored device times out,
Referring to the table corresponding to the connection position number of the monitored device, if the content is connected, an error report is transmitted to the higher-level device via the line, but if there is no connection, the error report is performed. No polling-type monitoring method.