JPH1168749A - Network system monitoring method and apparatus - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To suppress a load due to network management and automatically detect a change in state of an end-to-end communication link. A network management device and an end device are connected to communication processing devices connected to each other via individual networks. The link table creating means 21a of the link monitoring device 21 stores the network configuration information of the table 11b and the communication devices 31 to 3
5 and obtains a link table 21b indicating the link from one of the communication nodes of the entire network to the other by the metric number of the shortest path. Upon receiving the failure event from the communication processing device, the link creating unit 21a reacquires the route control table of the communication device linked to the failed device with the metric of 1, and updates the link table 21b. The link status display means 21c displays a link status between arbitrary end devices on the display 11d based on the link table 21b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a network system management apparatus, and more particularly, to a network link monitoring method and its means.

[0002]

2. Description of the Related Art A network management device manages the configuration and status of a network constituted by a plurality of devices and transmission paths, or a network system constituted by connecting a plurality of terminals and computers via the network. Therefore, a network management protocol is implemented in the network component device, and the network management device uses the protocol to request the network component device to provide information and receive the information.

When a state change such as a failure or power on / off occurs in a network component, an event is issued from the network component to the network management device, and the network management device receives the event. Detects a change in the state of the network. Upon detecting a failure of a network component device, the operator of the network management device determines the influence on end-to-end communication between end devices using the network based on the information of the failed device and the location of the device on the network. Was determined.

As another management method of end-to-end communication, communication link information for determining a communication path is obtained from a communication device on a network, and the communication path is analyzed. In the case of this method, the state of the end-to-end communication at the time of a failure is determined by acquiring path control information and the like from the communication devices on the communication link of the limited two end devices and examining the link state. .

[0005]

SUMMARY OF THE INVENTION A method for detecting the state of an end-to-end communication link based on configuration information such as fault information of network components and network topology information has been described by an operator of a network management apparatus. The analysis and judgment by a skilled network administrator require a considerable amount of time. A method of analyzing the experience of these skilled operators in a database is also being studied, but maintenance of the network configuration information database is required, and enormous analysis is required to analyze the link state of a large-scale network. Needs time.

The method of collecting communication link information such as path control information from network components can be applied to a method of monitoring the state of a relatively small number of communication links. However, when applied to a large-scale network, there is a problem that not only the load on the network management device but also the load on the network itself is greatly increased, and the communication function of the network is reduced.

SUMMARY OF THE INVENTION An object of the present invention is to overcome the problems of the prior art, suppress an increase in load due to network management, and apply the present invention to a large-scale network, and to realize the state of an end-to-end communication link in real time. An object of the present invention is to provide a network monitoring method and apparatus for detecting.

[0008]

In order to analyze the link state of a network, a method of constantly acquiring and analyzing path control information from all communication devices on the network, and a method of storing the current link state in a database or the like, There is a method according to the present invention in which when an event that causes a change in the link state is detected, necessary information is acquired and analyzed using the event as a trigger.

According to the present invention, there is provided a method for monitoring a network system comprising a plurality of communication processing apparatuses and a communication node including a plurality of networks. Based on the path control information obtained from each of the above, the number of metrics reflecting the link state from one of the communication nodes to the other in the entire system is obtained and managed for the shortest path, and the change in the link state of the network is measured by the number of metrics. And is monitored.

When the link state is changed, for example, when the communication processing device fails or recovers, the route control information after the change is obtained from the changed communication processing device or the communication processing device linked to the communication processing device with the metric number 1. The method is characterized in that the number of metrics between nodes in the range of influence of extraction or change between nodes that cannot communicate is calculated, and the number of metrics reflecting the link state is updated.

The calculation of the number of metrics on the shortest path is included in the path control information of the communication processing apparatus serving as the source node, and the one or more communication processing apparatuses serving as the next transfer destination are transmitted to the first reception destination. As a node, a metric number of 1 is set for all the links between the source and destination nodes, then the first destination node is set as the source node, and the metric set for the link between the destination nodes is set. This can be realized by adding 1 to the number, setting the value to the link between the first source node and the current destination node, and repeating this process.

[0012] According to this, data communication for obtaining the routing control information can be minimized, the load on the network and the communication device is not increased, and the link state is analyzed at high speed with the minimum information. Real-time state detection becomes possible.

The execution of the monitoring method of the present invention includes the steps of: generating and storing path control information of the own node;
In a network connecting between them, a monitoring device of a network system including an end device connected to the communication processing device, a transmission / reception unit for receiving an event or acquiring data, and a network including the communication processing device and the end device. A network configuration table for storing component device information and information on networks and branch lines; a network management device connected to one of the communication processing devices; And obtains the path control information from each communication processing device in the system via the network, and links from one (transmission source node) of the communication processing device or the communication node including the network in the entire system to the other (reception destination node). Link table showing the state by the number of metrics of the shortest path It made possible by providing the link table creating means for creating.

Furthermore, for any specified end device, the link table is referred to, and based on the number of metrics of the corresponding source node and destination node, whether or not communication between the end devices is possible and / or a communication path is provided. Is provided, the link state can be immediately grasped.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a LAN (Embodiment 1) and a composite LAN (Embodiment 2) will be described as embodiments of the present invention.
This will be described.

[Embodiment 1] FIG. 2 is a block diagram showing an example of a network system to which the network link monitoring method of the present invention is applied. In networks 51-56,
Communication processing devices 31 to 35 having a network control protocol and having a path control function are connected, and end devices 42 to 45 such as terminals, computers or servers are connected to branch lines 62 to 65 from the communication processing devices 32 to 35. ing.
The end devices 42 to 45 are non-management systems. Also,
A network management device 11 is connected to a branch line 61 from the communication processing device 31 to enable management of the communication processing devices 31 to 35 and acquisition of information from the end devices 42 to 45 using a network management protocol. Further, a link monitoring device 21 that manages a communication link state is connected to the network management device 11.

FIG. 1 is a functional block diagram showing the configuration and data flow of a network monitoring system according to one embodiment of the present invention. This system includes a network management device 1
1 and a link monitoring device 21.

The network management device 11 has basically the same configuration as the conventional one, and is a communication processing device 3 to be managed.
An event receiving function 11a for detecting a failure event or a recovery event from 1 to 35, a network configuration table 11b for storing network configuration definition information, a data acquisition function 11c for collecting route information and the like from a device to be managed, and displaying these information It has a display device 11d.

The link monitoring device 12 is configured as an additional function of the network management device 11, and is based on a link table 21b for managing a link state and route control information acquired from the communication processing devices 31 to 35 via the data acquisition function 11c. Link table creating means 21a for creating a link state of the network, a link table 21b for storing the created link state, and a link table 21b.
It has a link status display means 21c for displaying on the display device 11d based on the link status of b.

The communication processing devices 31 to 35 have a routing control table creating means 30a and a routing control table 30b in addition to a transmission / reception function (not shown) as in the prior art. The route control table creating means 30a edits the current destination network IP of the own node, the number of metrics between them, and the node IP to be the next transfer destination, and stores them in the route control table 30b.

The link monitoring device 21 starts operation,
From the network configuration table 11b, the communication processing device 31
Obtain the IP addresses of ~ 35. FIG. 3 shows a network configuration table. (A) is a component device table,
For example, the communication processing devices 31 to 35 have 3 to 4 respectively.
IP address and host name are set. (B)
Is a network table in which network addresses and network names of the networks 51 to 56 and the branch lines 61 to 65 are defined.

Next, using the data acquisition function 11c of the network management device 11, a request for transmission of a routing control table (routing table) is made to the communication processing devices 31 to 35 to acquire the respective routing control information. Then, the obtained route control information is edited, and a link table 21b indicating the link state of the network is created.

FIGS. 4 and 5 show the route control tables (a) to (e) obtained from the communication processing devices 31 to 35, respectively. In the path control table, the network IP and metric number of the other party of the communication processing apparatus, and the IP address of the communication processing apparatus to be the next transfer destination are set. The metric is
It represents the number of communication processing devices on the communication path reaching the target node, and is the number of metrics according to the communication path.

FIG. 6 shows an example of the created link table. The link table 21b manages metrics from a transmission source to a reception destination in the network.
The intersection of the source node in the vertical column of the table and the destination node in the horizontal column is used as a link, and communication processing devices of all networks and unit networks (including branch lines) are arranged at each node.
By setting the number of metrics for the links between the nodes, it is devised that the link state between the nodes in the network can be easily grasped dynamically.

FIG. 7 shows a flow chart for creating a link table. The link table creation unit 21a is configured to transmit the communication processing devices 31 to 35 from the network configuration table 11b.
Is obtained (s10). Next, the routing control table is sequentially requested by the IP address, and when the routing control table can be obtained (s20), the number of metrics with the network and the name of the communication processing device to be transmitted next are obtained (s30). If the routing control table cannot be obtained, the process skips step s30. Next, the communication processing device 3
When the routing control table can be obtained from all of the nodes 1 to 35 (s40), the number of metrics that is the shortest route between the source and destination nodes is calculated and set in the link table (s50).

FIG. 8 shows a detailed procedure of the process s50.
First, the name of the communication processing device to be the next transfer destination is obtained from each of the route control tables of the communication processing devices 31 to 35 (s51). In the link table, the metric number 1 is set to all the links between the communication device of the transmission source node and the communication device (name acquisition) as the transfer destination thereof to the reception destination node (s52).

Then, in the order of the transmission source nodes on the link table, first, the communication device linked to the transmission source node with the metric 1 and the metric number m of the reception destination node are acquired on the link table (s53). ). Next, m is added to the link between the transmission source node and the reception destination node in step s53.
A metric number of +1 is set (s54).

In the process s54, the link is initially acquired from the link of m = 1, but the link of m = 2 or more gradually increases, and the number of metrics of all communicable links is set. Here, the link between the transmission source node and the reception destination node is sequentially traced starting from the one having the relationship of m = 1 in order to minimize the linking route.

The above process is repeated for all the source nodes until the link table setting process is completed (s5).
5) If there is an undetermined link in the link table after the end, communication is not possible between the nodes, and the metric number (for example, m = 16) indicating that is set (s5).
6).

The link status display means 21c pre-registers the end devices to be managed and, based on the created link table 21b, provides a graphical overview of the current link status between the end devices and the details of the link path. To be displayed.

FIG. 12 shows an example of an end network in the network.
FIG. 4 shows a link state diagram for two-to-end communication. (A) is a schematic diagram showing the current availability of communication between registered end devices (this example is all possible), and (b) is a detailed diagram of a link path between end devices. Thus, the network administrator can grasp at a glance the link state between the registered end devices. The name of the communication processing device displayed on the link route is accumulated in the process of obtaining the metric number of the shortest route when creating the link table.

Next, the operation of the system when the link state of the network changes will be described. For example, when a failure occurs in the communication processing device 34 to make it inoperable, the communication processing device 34 sends a failure event, which is one function of a network management protocol, to the network management device 11. Note that the other communication processing device is the communication processing device 34.
May be detected, and a failure event may be transmitted to the network management apparatus 11. Upon receiving the failure event, the network management device 11 transmits failure information of the communication processing device 34 to the link monitoring device 21.

The link monitoring device 21 searches the link table 21a using the failure information as a trigger, and detects the communication processing devices 32, 33, and 35 to which the failed communication processing device 34 is linked with metric = 1. When there is a communication processing device linked to an arbitrary communication processing device with a metric of 1, the link state is called a network link.

Next, the detected communication processing devices 32, 33,
A transmission request of the routing control table is made only to the server 35. FIG.
9 shows a routing control table acquired from the communication processing devices 32, 33, and 35. Compared to FIGS. 4 and 5, the route via the communication processing device 34 is deleted from these route control tables, indicating that the link is broken. As described above, the link table 21b can be updated using only the route control information of the communication processing device that has been network-linked to the inoperable communication processing device 34.

FIG. 10 shows a flowchart of the link table updating process. This process is started with the failure information as a trigger. With respect to the failed node from the failure information, the presence / absence of a corresponding node that is network-linked is searched from the link table 21b (s110). Next, the presence or absence of the corresponding node for acquiring the routing control table is checked (s1
20), if there is, an acquisition request is transmitted to acquire the routing control table (s130), and FIG.
To update the link table (s14).
0). Steps s150 and s160 are executed in the case of a second embodiment described later.

FIG. 11 shows a link table updated when a failure occurs in the communication processing device 34. For example, when RIP, which is a routing protocol for route control, is used, the maximum metric is 15, and therefore, a metric indicating that communication is not possible is represented by 16. The portion that has changed from the metric before the failure of the communication processing device 34 (FIG. 6) is shown in black. Transmission and reception of the communication processing device 34 and transmission and reception of the branch line 64 from the communication processing device 34 are all disabled. Further, the mutual metric of the communication processing device 33 and the branch line 63 and the mutual metric of the communication processing device 35 and the branch line 65 change, indicating the link state and the range of influence of the end-to-end communication due to the failure of the communication processing device 34.

FIG. 13 shows the end server updated due to the failure.
FIG. 4 shows a link state diagram for two-to-end communication. Compared to FIG. 12 before the failure of the communication processing device 34, the schematic diagram of FIG.
The link between the end device 42 and the end device (CRT) 44 and the link between the end device 43 and the end device (CRT) 44 are defaulted (double line), and a fault is displayed.
In the detailed diagram (b), the communication path of the fault display unit is deleted, and for example, the communication path from the end device 43 to the end device (CRT) 45 is the communication processing device 33, 34, 35 before the failure. Is changed from a route with a metric of 3 to a detour route with a metric of 4 through the communication processing devices 33, 32, 31, and 35.

From the schematic diagram and the detailed diagram shown in FIG. 13, the network administrator can check the communication failure between the end devices 42 and 43 and the end device 44 and the change in the link state between the end devices 42 and 43 and the end device 45. Can be grasped immediately. Also, in response to a complaint from the user such as an increase in network load, the cause and the range of influence can be answered.

Next, the operation of the system when the communication processing unit 34 recovers from a failure will be described. When receiving the recovery event from the communication processing device 34, the network management device 11 transmits failure information of the communication processing device 34 to the link monitoring device 21. With this as a trigger, the link monitoring device 21 searches the link table, and the communication processing device 34
The communication processing units 32, 33, and 35 with the number of metrics = 16 in a state where communication with the communication processing is impossible are detected. Thereafter, the link table is updated by the processes s120 to s140 of FIG. As a result, the link table is restored to the state shown in FIG. 6 and the link state between the end devices is restored to the state shown in FIG. 12, so that the network administrator can immediately confirm the link state after the restoration.

As described above, according to the network monitoring system of the present embodiment, when the network is started, the link monitoring means added to the network management device uses the network configuration information and the route control information generated by each communication processing device. First, a link table is created and managed which indicates the link relationship between nodes (communication processing devices, networks, and branch lines) in the entire network by the number of shortest path metrics.
When a failure event of the communication processing device is received, the route control information edited after the occurrence of the failure is acquired from each communication processing device having a metric of 1 (network link) with the failed communication processing device, and the route control information between the nodes is obtained. Recalculate the metrics and update the number of metrics in the link table.
The link in which the number of metrics has changed in the updated link table reflects a communication failure due to a failure or a link state of a route change. Therefore, it is possible to easily grasp the state of communication failure between arbitrary end devices in the network due to the occurrence of a failure, and the influence of a failure such as a change in a communication path, and to display it visually.

The update of the link table at the time of occurrence of a failure is limited to the communication processing device linked to the failed communication processing device with the minimum metric number, and the route control information is collected. Since only a short amount of processing is required to find the number of metrics for links to be linked, the load on the network and the network monitoring system is small,
There is no degradation of network function. Also, without relying on the experience of the network administrator, the link status in the network due to failure or recovery can be instantly confirmed on the screen by specifying any end device, making it easy to use and easy to manage the network. I do.

[Embodiment 2] Next, a network link monitoring method according to the present invention will be described with reference to a large-scale network (WAN).
A description will be given of an embodiment applied between local networks (LANs) coupled to a network.

FIG. 14 shows a schematic configuration diagram of an application system. Each of the areas 71 and 72 has the same configuration as the network system of FIG. For example,
The area 71 includes the same communication devices 31 to 35, end devices 42 to 45, networks 51 to 56, and branch lines 61 to 6 as in FIG.
5 are collectively shown as a LAN 91. LAN91
Is connected to the network management device 11 to which the link monitoring device 21 is added. The LAN 92 in the area 72 is similarly aggregated, and connects the network management device 12 to which the link monitoring device 22 is added. The area 71 and the area 72 are connected by a WAN 81 via a large-scale network.

Now, in the area 71, as in the case of the first embodiment, it is assumed that a failure has occurred in the communication device 34 shown in FIG. At this time, the network management device 11 that has received the failure event transfers the failure information of the communication device 34 to the link monitoring device 12, and this triggers the link monitoring device 12 to update the link table.

FIG. 15 shows a data flow diagram of the link table update processing. The link monitoring device 12 is a communication device 3
4, the communication devices 32, 33,
35 is detected from the link table 21b, a transmission request of the routing control table is issued to them, and the data acquisition function is set to 1
1c, and updates the link table 21b by performing the update process of FIG. At this time, in steps s150 and 160, the link monitoring device 21 notifies the network management device 12 of the area 72 of the link table update event, and transmits the updated link table 21b to the link monitoring device 22. The link monitoring device 22 manages the received link table 21b and can recognize the link state of the area 71. The same applies when the communication device 34 recovers.

The updated link status is not automatically transmitted to the area 72, and the link table 21b is transmitted to the link monitoring device 22 in response to the request from the area 72 for confirming the link status of the area 71. Is also good. Also,
As in the first embodiment, the network manager of the area 72 can easily check the link status between the end devices on the screen from the received link table 21b.

According to the present embodiment, even in a wide area network connecting a plurality of LANs, a network monitoring device is connected to each LAN to perform real-time management of the link state of the network and to exchange the information comprehensively. As a result, even in a wide area network connecting a plurality of LANs, it becomes possible to automatically and in real time monitor a change in the state of the link of the end-to-end communication of another LAN.

[0048]

According to the present invention, the link state between the nodes of the network is indicated by the metric number, and the change in the link state due to the failure or restoration of the communication processing device is updated and managed in real time. Changes in the state of the two-end communication link can be monitored automatically. In addition, since information required for the update process is limited and can be processed in a short time, an increase in the amount of monitoring traffic is minimized and the communication function of the network is not affected.

Further, since the state change of the communication link can be displayed on the screen between arbitrary end devices, the end user affected by the failure of the network component device can be easily grasped, and the recovery according to the range of influence can be performed. Since measures can be taken, network management becomes easy.

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a network monitoring system according to one embodiment of the present invention.

FIG. 2 is a configuration diagram of a network system according to a first embodiment to which the present invention is applied.

FIG. 3 is a configuration diagram of a network configuration information table according to one embodiment.

FIG. 4 is a configuration diagram of a path control table according to one embodiment.

FIG. 5 is a configuration diagram of a route control table continued from FIG. 4;

FIG. 6 is a configuration diagram of a link table according to one embodiment.

FIG. 7 is a flowchart showing a procedure for creating a link table according to the embodiment;

FIG. 8 is a flowchart showing details of a metric setting process of FIG. 7;

FIG. 9 is a configuration diagram of a path control table acquired from a communication device after a failure occurs.

FIG. 10 is a flowchart showing a procedure for updating a link table after a failure occurs.

FIG. 11 is a configuration diagram of a link table after updating.

FIG. 12 is a view showing a link state according to the embodiment;

FIG. 13 is a link state display diagram based on the updated link table.

FIG. 14 is a configuration diagram of a large-scale network system according to a second embodiment to which the present invention is applied.

FIG. 15 is a data flow diagram when the link table is updated in the network monitoring system according to the second embodiment.

[Explanation of symbols]

11, 12: Network management device, 11a: Event transmission / reception function, 11b: Network configuration table, 11
c: Data acquisition function, 21, 22: Link monitoring device, 2
1a: Link table creation means, 21b: Link table, 21c: Link status display means, 31 to 36: Communication device, 42 to 45 ... End device, 51 to 56: Network, 61 to 67: Branch line, 71, 72 ... Area , 81 ... wide area dedicated line (WAN), 91, 92 ... LAN.

Claims (6)

[Claims] 1. A method for monitoring a network system comprising a plurality of communication processing devices and a communication node including a plurality of networks, comprising: when starting up a system, routing control information acquired from each of the communication processing devices; Based on the shortest path, manages the number of metrics reflecting the link state from one of the communication nodes to the other in the entire system, and monitors the change in the link state of the network by reflecting the change in the number of metrics. Network system monitoring method. 2. The path control according to claim 1, wherein, when the link state is changed, for example, when the communication processing device has failed or recovered, the changed communication processing device or the communication processing device linked to the communication processing device with the metric number 1 is changed. A method for monitoring a network system, comprising: acquiring information, calculating the number of metrics between nodes in an affected range of extraction or change between nodes that cannot communicate, and updating the number of metrics reflecting the link state. 3. The communication method according to claim 1, wherein the calculation of the number of metrics in the shortest path is included in path control information of a communication processing apparatus serving as a source node, and one or more communication destinations serving as a next transfer destination are included. With the processing device as the first destination node, the metric number 1 is set for all the links between the source and destination nodes. Next, the first destination node is set as the source node, and the link between the destination nodes is set. A method for monitoring a network system, comprising adding 1 to the number of metrics set for a link, setting the value to the link between the first source node and the current destination node, and repeating this process. . 4. A monitoring system for a network system, comprising: a plurality of communication processing devices for generating and storing path control information of a self-node; a network connecting the plurality of communication processing devices; and an end device connected to the communication processing device. A transmission / reception unit for receiving an event or acquiring data; and a network configuration table for storing information on component devices of a network including the communication processing device and the end device, and information on a network and branch lines, and one of the communication processing devices. A network management device to be connected, and the function of the network management device is attached to be available,
The path control information is obtained from each communication processing device in the system via the transmission / reception means, and one (transmission source node) of the communication processing device or the communication node including the network in the whole system (a destination node) A monitoring apparatus for a network system, comprising: a link table creating unit that creates a link table that indicates a link state to a link by a metric number of a shortest path. 5. The communication between the end devices according to claim 4, wherein, for any specified end device, the link table is referred to, and based on the number of metrics of the corresponding source node and destination node, whether communication is possible between the end devices is determined. And / or a link status display unit for displaying a communication path. 6. A plurality of communication processing devices, a network connecting them, and a plurality of local area networks (hereinafter, referred to as LANs) each including an end device connected to the communication processing devices are connected to a wide area network (WA).
A network system connected by N), wherein each of the LANs is provided with the monitoring device of the network system according to claim 4 or 5, when the link table is created or updated, or when an inquiry from another LAN is made. Accordingly, the information of the link table is stored in another LA.
A monitoring device for a network system, wherein the monitoring device is configured to be able to transmit to the network system.