JPH09101929A - Trap transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely deliver TRAP generated at a node to be managed to a managing station in a network management or system management using SNMP. SOLUTION: MIB 75 for TRAP reception confirmation is defined and at the time of TRAP reception, a managing station 1 transmits a SET request so that the value of MIB for TRAP reception confirmation in response to the received TRAP can be set at a value expressing the completion of reception. After the TRAP is transmitted by a node 2a to be managed, the value of MIB for TRAP reception confirmation in response to the transmitted TRAP is monitored and when that value is not set to the value expressing the completion of reception even after the lapse of certain fixed time, the retransmitting processing of TRAP is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to network management or system management using SNMP, and more particularly to a device for notifying an event occurring in a managed node as a TRAP to a management station.

[0002]

2. Description of the Related Art SNMP, which is a standard management protocol for TCP / IP networks, will be explained, and then SN
The transmission means of the standard TRAP defined in MP is shown as the prior art.

SNMP is, for example, M. T. Written by Rose / Translated by Takeshi Nishida TCP / IP Network Management Primer As described in Toppan Co., Ltd., management information is collected from nodes in the network, setting processing is performed, and notification processing of events that occur in nodes is performed. This is a network management protocol specified for performing the communication, and is realized by the manager program in the management station and the agent program in the managed node sending and receiving messages to and from each other. Here, in SNMP, management information is called MIB and event is TR.
Call it AP. Then, UDP / IP is recommended as a lower protocol of SNMP, and most of the SNMP-related products follow this.

That is, the manager program in the management station collects / sets MIBs (message route information, traffic information such as the number of transmitted / received messages, fault information, etc.) using UDP / IP packets in the managed node. Send a request message to the agent program. The agent program collects / sets the requested information, sets the result in a response message, and sends it in a UDP / IP packet to the manager program. In addition, the managed node voluntarily sends TRAP without request from the management station.
Send in DP / IP packet to the management station. In UDP, there is no guarantee that the message will reach the other party without retransmission processing. Further, since TRAP only exchanges one-way messages from the management node to the management station and has no response, it is possible to confirm that the TRAP will be delivered even if it is sent to the management station, and to confirm whether or not it has arrived. Can not.

Currently, the standard TRAP defines a TRAP that is transmitted when the state (UP / DOWN) of the network interface changes or when an invalid request is received from the management station. And
These TRAPs are sent by the agent program,
The message transmission process is executed only once, and no confirmation is made as to whether it has reached the management station.

[0006]

In a management system using SNMP, management is generally performed by polling monitoring from a management station to a managed node. However, in polling monitoring, since a request / response message flows on the network every time monitoring is performed, there are problems that the network load increases when the number of managed nodes increases, and the overhead of the management station increases. Then, in order to realize management in more real time, it is necessary to perform processing such that monitoring is performed by the managed node and TRAP is transmitted to the management station only when an abnormality occurs.

Under such circumstances, the SNMP T
Using RAP does not guarantee that it will reach the other party. And because TRAP has disappeared, there is a possibility that a failure cannot be detected or a failure can be sent.
There was a problem that important management could not be performed.

Reliable communication (eg TCP / IP)
However, in this case, all the TRAP transmission / reception methods between the management station and the managed node must be changed, which results in a unique management method.

An object of the present invention is to reliably deliver a TRAP to a management station using SNMP standard management.

[0010]

Means for Solving the Problem The above problem is that when a management station receives TRAP, it provides means for transmitting a message indicating normal reception of TRAP to a TRAP transmission source using SNMP. TRA
P Received message indicating normal reception is monitored, and when no message is received after waiting for a certain period of time, TRAP
For retransmitting the packet, and TRA after the TRAP is retransmitted
This is achieved by providing means for repeatedly performing the TRAP retransmission process until a message representative of P normal reception is received.

When the TRAP transmitted from the managed node is lost by the above means, the message indicating the normal reception of TRAP from the management station is not transmitted to the TRAP transmission source. Then, after a certain period of time, TRAP
Is retransmitted. This TRAP retransmission processing is repeatedly executed until the message indicating the normal reception of TRAP from the management station is received.
Even if P is continuously lost, TRAP can be reliably delivered to the management station.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) In this embodiment, it is assumed that network management or system management is realized using SNMP.

FIG. 2 shows the overall configuration of a system to which the present invention is applied. The management station 1 and the managed nodes 2a to 2d are connected to a LAN 3, and communication is performed on this LAN using TCP / IP.

A software configuration of the management station 1 and the managed nodes 2a to 2d is shown.

As shown in FIG. 3, the software structure of the management station is the SNMP-API 31 for realizing the SNMP.
And a TRAP receiving process 32 for receiving a TRAP from the managed node.

As shown in FIG. 4, the managed nodes 2a and 2b include an SNMP-API 41 for realizing SNMP, an agent 42 for processing an SNMP request from a management station, a TRAP transmission command 43, and a TRAP.
It is composed of a reception confirmation monitoring process 44 and a TRAP management table 45.

The TRAP transmission command 42 is a command for transmitting an event generated in the managed node as a TRAP to the management station. On the managed node,
When status / fault monitoring is executed and an event is detected, TRAP is transmitted using this command. In this embodiment, the processing for detecting an event in the managed node is omitted.

Here, a process when an event is detected in the managed node and the TRAP transmission command is activated will be described.

The command parameter is data required when creating a TRAP message, and in order from the first parameter, the TRAP transmission destination address, the enterprise ID, the agent address, and the generic-
It is a trap, a specific-trap number, and a variable list.

The enterprise ID is an ID for identifying the agent, and the agent address is T
IP address of the node that generated the RAP, generi
The c-trap and the specific-trap numbers are numbers representing the content of this TRAP, that is, the factor that has occurred. A number is determined in advance for this generic-trap, and 6 must be used for a unique TRAP, but a number can be freely determined for the specific-trap. The variable list specifies information about TRAP and can be omitted if unnecessary.

When the parameters are specified and the TRAP transmission command is activated, the flow shown in FIG. 5 is executed. When activated, first, a check process of designated parameters is performed (process 51). Then, after obtaining the time stamp value, a TRAP message is created (processes 52, 5).
3). The time stamp is the time elapsed since the agent was last started, and this value uniquely identifies the TRAP.

The format of the TRAP message is shown in FIG.
Shown in

Enterprise ID, agent address, generic-trap and specific-t
Areas 61 to 66 for setting a rap, a time stamp, and a variable list. Here, all the fields other than the time stamp are parameters specified when the command is started, and the specified values are set.

The variable list is name (areas 6a, 6
c) and value (areas 6b and 6d). The ID of the management information to be set is set in name, and the value indicated by the ID is set in value. The number of names and values match the number of information to be set, and this field is omitted unless otherwise specified.

After the TRAP message is created in the process 53, the TRAP information is registered in the TRAP management table (process 54). This table is accessed by the agent 42 and the TRAP reception confirmation monitoring process 44, and is a table necessary for executing the TRAP reception confirmation and the retransmission processing.

As shown in FIG. 7, the TRAP management table 45 is composed of fields 71 to 75 for setting a serial number, a timer value, a transmission address, a TRAP message, and a TRAP reception confirmation MIB. A time stamp value is set in the serial number, and a timeout time is set in seconds in the timer value. In the TRAP reception confirmation MIB, the SET processing of the field value is performed by the SNMP request from the management station. When registering, set the value to 0. In this embodiment, the object type of the TRAP reception confirmation MIB is defined as 1.2.3, and when the value is 0, the reception has not been confirmed, and when the value is 1, the reception has been confirmed. TR
After registering each data in the AP management table, TRAP is transmitted to the designated destination (process 55).

Next, the processing when the management station receives the TRAP is shown.

The TRAP is received by the TRAP receiving process and executes the flow shown in FIG. When TRAP is received, the contents of TRAP are set to the time, source address (I
It is displayed in a window together with (P address) to notify the user that an event has occurred (process 81, 82). Next, a SET request message indicating that TRAP has been normally received is created (process 83). The request message and the response message have the same format and are shown in FIG. The request ID (code for identifying management information collection or setting) of the message, areas 91 to 93 for setting an error status and error INDEX, and an area 94 for setting a variable list. The error status and the error INDEX are areas that are valid at the time of the response message, and error information (whether the processing has ended normally or not, and details of the error if abnormal) is set. The variable list is the same as the TRAP message.
(Areas 9a and 9c) and value (Areas 9b and 9)
d). The ID of the requested management information is set in name, and the value indicated by the ID is set in value.

In SNMP, the ID actually specified when operating the management information is a value obtained by adding an instance index to the suffix of the object type of the defined management information. What is this instance index?
For uniquely identifying management information, if there is only one in a node ,. 0 is used, and if there are a plurality of them, an interface number, an IP address, etc. are generally used to specify individual information. Here, in order to uniquely identify TRAP,
The time stamp set in TRAP is used for the instance index.

As shown in FIG. 1, for the TRAP receipt confirmation MIB for the received TRAP, a SET request message for setting the MIB value to 1 is created, and TRAP is created.
It is transmitted to the transmission source node (process 84). Set a code indicating the SET request in the request ID, and set val
ue is a value obtained by adding the time stamp value set in the received TRAP to the object type of the MIB for confirming the reception of the TRAP (when the time stamp value is 50, 1.
2.3.50) and 1 is set in name.

When the transmission process is completed normally, the next TRA
If it enters P reception waiting state and ends abnormally, S again
The ET request message is transmitted (process 85). S
The ET request has a response of GET response, and this message confirms that the SET process has been normally completed. The GET response complies with the SNMP regulations.

Next, FIG. 10 shows the processing for the SET request in the managed node.

All SNMP requests from the management station are processed by the agent. The agent is waiting for receiving an SNMP request (Processing 10
1) When the request is received, the request type (SE
T / GET), and name and value are checked, collection / setting processing is performed on the management information specified by name, and the result is transmitted to the management station as a GET response message (processing 102 to 10).
4).

In the management information collecting / setting process of process 102,
When a SET request for the TRAP reception confirmation MIB is received, the processing shown in FIG. 11 is executed. First, nam
A time stamp value is acquired from the ID designated by e (process 111). Next, the serial number area in the TRAP management table is sequentially checked and an entry having the same value as the time stamp value is searched (process 112). Then, the TRAP reception confirmation MIB of that entry is set to the value specified by value (process 113).

By these processes, T
When sending RAP, the TRA is sent by the TRAP send command.
Registration in the P management table is performed, and when the management station receives the TRAP, it transmits a request request for setting a value to the reception confirmed MIB (= 1) for the TRAP reception confirmation MIB for the received TRAP. Then, the agent in the managed node confirms the reception of the TRAP reception confirmation MIB in the TRAP management table (=
1) is set.

Next, the processing of the TRAP reception confirmation monitoring process will be described. This process is activated every 1 second and executes the flow shown in FIG. The TRAP reception confirmation MIB is sequentially checked for all entries in the TRAP management table (processes 121 and 122). Confirmed receipt (= 1)
If so, go to the check process for the next entry. If reception is not confirmed (= 0), it is checked whether the timer value is 0 or not. If the timer value is not 0, the timer value is decremented (process 124). If the timer value is 0, the timer value is set to the initial value and the TRAP retransmission process is executed (processes 125, 1).
26). A TRAP message and a destination address are set in each entry, and TRA is used by using this data.
Send P again. After the above processing is performed for all the entries in the table (processing 127), the processing ends.
As a result, the TRAP retransmission process is repeated until the value of the TRAP reception confirmation MIB is set to reception confirmed (= 1) before the timer value becomes 0.

When the TRAP transmitted from the managed node disappears by the processing of the management station and the managed node, the TRAP reception process in the management station does not execute the SET request request for the TRAP reception confirmation MIB. The TRAP reception confirmation MIB value in the TRAP management table in the managed node remains the initial reception unconfirmed state (= 0), and the TRAP reception confirmation monitoring process decrements the timer value at 1-second intervals, and the timer value When T becomes 0, the TRAP retransmission processing is performed. This TRAP retransmission processing is repeatedly executed by the SET request from the management station until the TRAP reception confirmation MIB value becomes reception confirmed (= 1), so that TRAP can be reliably transmitted to the management station. .

(Embodiment 2) In the second embodiment, when a TRAP is transmitted by a managed node, a function is provided which can select whether or not reliability is required. When reliability is required, the TRAP is delivered to the management station without fail,
If not, we do not guarantee delivery of TRAP. The process when reliability is required is the same as that in the first embodiment. The difference is that TRAP transmission processing (TRAP
Transmission command) and reception processing (TRAP reception process)
Therefore, when reliability is not required, TRAP can be reliably performed.
Is omitted, and a flag for identifying whether or not reliability is required is added to the TRAP message.

Hereinafter, description will be given with reference to the drawings of the first embodiment.

A reliability request flag for identifying whether to request reliability is added to the parameter of the TRAP transmission command. In the processing flow of the TRAP transmission command (FIG. 5), if reliability is requested by referring to this flag, the processes 51 to 55 are executed as in the first embodiment, but if reliability is not requested. , The TRAP management table is not registered (process 54), and the TRAP transmission process is performed.

A reliability request flag is added to the variable list as management information in the TRAP message. The object type of the reliability request flag is 1.2.4, the value when the reliability is not requested is 0, and the value when the reliability is requested is 1. Here, TR that the reliability request flag means
Since one AP is uniquely identified, 0 is used for the instance index. The name of the variable list is set to 1.2.4.0, and the value is set to either 0 or 1.

In the processing flow of the TRAP receiving process in the management station (FIG. 8), after receiving TRAP and displaying it in the window (processing 81, 82), the reliability request flag set in the variable list is checked, If the reliability is required, the processes 81 to 85 are executed as in the first embodiment. If the reliability is not required, the process 83 is performed.
The process of transmitting the SET request message up to 85 is omitted.

By these processes, the reliable TRAP and the non-reliable TRAP are specified by designating whether or not the reliability is required by the parameter of the TRAP transmission command.
The RAP can be selected and transmitted.

(Third Embodiment) In the first embodiment, it is confirmed by the SET request from the management station whether the TRAP is normally received. In the third embodiment, the TRAP indicating the TRAP reception is received from the management station. By receiving it, it is confirmed whether it is normally received.

The software configuration of the management station is the first embodiment.
Same as the above, but a reception confirmation TRAP reception process is added in the managed node.

As for the TRAP transmission command, TRAP is transmitted by the same processing as in the first embodiment.

The TRAP reception process in the management station executes the flow shown in FIG. First, a TRAP reception waiting state (process 131)
Is displayed in the window (process 132). next,
A TRAP message indicating that TRAP has been normally received is created (process 133).

Spcific-in the TRAP message
The trap number is 100, and the time stamp value set in TRAP is set in the variable list. The managed node refers to these values to determine which T
Receipt confirmation for RAP This is identified as TRAP.

After the TRAP message is created in step 133, the reception confirmation TR is sent to the sender of the TRAP message.
Send AP.

Next, the TRAP receiving process in the managed node will be described.

The TRAP is received by the acknowledgment TRAP receiving process and executes the flow shown in FIG. First, the TRAP reception waiting state (process 141), TR
When the AP is received, it is checked whether or not it is the reception confirmation TRAP by referring to the specific-trap number (Process 14).
2). If it is not the reception confirmation TRAP, the processing returns to step 141, and if it is the reception confirmation TRAP, the time stamp value set in the variable list is acquired (processing 143). next,
The serial number area in the TRAP management table is sequentially checked to search for an entry having the same value as the time stamp value (process 144). Then, the TRAP reception confirmation MIB of the entry is set to reception confirmed (= 1) (process 1
45) Return to processing 141. Although the TRAP reception confirmation MIB is set by the agent in the first embodiment, the TRAP reception confirmation MIB is set by the reception confirmation TRAP reception process in the third embodiment.

The TRAP reception confirmation monitoring process executes the same processing as that of the first embodiment. If the value of the TRAP reception confirmation MIB is not set to 1 within the timeout time, the TRAP retransmission processing is executed. With these processes, TRAP can be reliably delivered to the management station as in the first embodiment.

[0053]

The TRAP generated in the managed node can be reliably delivered to the management station. For this reason,
Events that occur on the managed node cannot be detected or event detection is not delayed.

[Brief description of the drawings]

FIG. 1 is a block diagram of SET request processing that is a feature of the present invention.

FIG. 2 is a block diagram of a system suitable for applying the present invention.

FIG. 3 is a block diagram of software of a management station.

FIG. 4 is a block diagram of software of a managed node.

FIG. 5 is a flowchart of a TRAP transmission command.

FIG. 6 is an explanatory diagram of a format of a TRAP message.

FIG. 7 is an explanatory diagram of a TRAP management table.

FIG. 8 is a flowchart of a TRAP reception process.

FIG. 9 is an explanatory diagram of a request / response message format.

FIG. 10 is a flowchart of an agent.

FIG. 11 is a flowchart of SET processing for a TRAP reception confirmation MIB.

FIG. 12 is a flowchart of a TRAP receipt confirmation monitoring process.

FIG. 13 is a flowchart of a TRAP receiving process according to the third embodiment.

FIG. 14 is a flowchart of a reception confirmation TRAP reception process of the third embodiment.

[Explanation of symbols]

name ... ID of management information, value ... Value of management information.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomohisa Hatano 1099, Ozenji, Aso-ku, Kawasaki-shi, Kanagawa, Ltd. System Development Laboratory, Hitachi, Ltd. (72) Minor Koizumi 1099, Ozenji, Aso-ku, Kawasaki, Kanagawa Hitachi, Ltd. Manufacturing Systems Development Laboratory (72) Inventor Hiroshi Wataya 5-2-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Omika-Factory (72) Inventor Jun Suzuki 2-5-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Process Computer Engineering Co., Ltd. (72) Inventor Tetsuhiko Hirata 1099, Ozenji, Aso-ku, Kawasaki-shi, Kanagawa Hitachi, Ltd. System Development Laboratory

Claims (6)

[Claims] 1. An M for checking TRAP reception in network management using SNMP or system management.
A means for defining the IB and realizing collection / setting processing for the MIB value, when the management station receives the TRAP, the reception T
Means for transmitting a SET request request to the TRAP transmission source for setting the MIB value for confirmation of TRAP reception for the RAP to the TRAP transmission source, for TRAP reception confirmation for the transmission TRAP after TRAP transmission by the managed node Of the TRAP, the means for performing the TRAP retransmission processing when the value indicating that the reception has been completed is not set even after waiting for a certain period of time, the TRAP reception confirmation MIB value for the retransmission TRAP after the TRAP is retransmitted by the managed node. A TRAP transmitting apparatus comprising means for monitoring and repeatedly performing a TRAP retransmission process until a value indicating that the signal has been received is set. 2. An M for confirming TRAP reception in network management using SNMP or system management.
Define IB and set MIB value from management station
A TRAP transmitting apparatus, which confirms whether or not TRAP is normally received depending on whether or not there is a request. 3. An M for confirming TRAP reception in network management or system management using SNMP.
A TRAP transmission device that defines IB and confirms whether or not TRAP is normally received according to the MIB value. 4. The MIB for confirming TRAP reception, which exists for each TRAP transmitted by a managed node according to claim 3.
In response to the value, the management station uses the time stamp value set in TRAP to specify which TRAP to which the TRAP reception confirmation MIB value SET request is sent. 5. The TRA in the managed node according to claim 1.
Means for selecting whether or not to require reliability when sending P,
And means for setting in the TRAP a flag for identifying whether or not reliability is required according to the selected request, the management station refers to the flag set in the TRAP when the TRAP is received, and Only when sex is required,
A TRAP transmission device provided with means for transmitting, to a TRAP transmission source, a SET request request for setting a MIB value for TRAP reception confirmation for a reception TRAP to a value indicating reception completion. 6. In network management using SNMP or system management, a means for defining a TRAP indicating a normal reception of TRAP, and a TRA at the management station.
When P is received, a means for transmitting a TRAP indicating normal reception of the received TRAP to the TRAP transmission source, and after the TRAP is transmitted by the managed node, the TRA for the transmitted TRAP
P A means for performing TRAP retransmission processing when TRAP indicating normal reception is monitored and TRAP is not received even after waiting for a certain period of time.
The TRA is provided with means for monitoring the TRAP indicating the normal reception of the TRAP with respect to the RAP and repeatedly performing the TRAP retransmission process until the TRAP is received.
P transmitter.