CN1610309A

CN1610309A - Development method of management agent for supporting simple network management protocol

Info

Publication number: CN1610309A
Application number: CN 200310101730
Authority: CN
Inventors: 刘美丽; 曹诗勇; 徐庆伟; 张先萍
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2003-10-22
Filing date: 2003-10-22
Publication date: 2005-04-27
Anticipated expiration: 2023-10-22
Also published as: CN100337431C

Abstract

The present invention discloses one kind of simple network management protocol agent (SNMP Agent) developing method. The method includes the following steps: the step A for the management information base (MIB) compiler to create separate MIB tree files, Get/GetNext/Set processing flow files and inform sending interface files based on designated MIB files; the step B to program low layer data operation function preserved in the Get/GetNext/Set processing flow files and to perfect the processing flow codes; the step C to add the MIB subtree and Get/GetNext/Set processing flow of the MIB tree files into SNMP Agent, and call directly corresponding inform sending interface file functions in where inform sending is needed; and step D for the compiler to co-compile the processing codes obtained in the last step and SNMP Agent kernel codes to create SNMP Agent program.

Description

A kind of development approach of supporting the administration agent of Simple Network Management Protocol

Technical field

The present invention relates to a kind of data communication technology, relate to the development approach of a kind of employing MIB (MIB) compiler or rather the administration agent (Agent) of support Simple Network Management Protocol (SNMP).

Background technology

SNMP is the most popular network management standard of industry, but all relies on this network management protocol to carry out communication between manager and the nearly all management equipment.As most of data communications equipment, comprise router, access server, ATM(Asynchronous Transfer Mode) switch, LAN switch (LAN SWITCH), ADSL (Asymmetric Digital Subscriber Line) (ADSL) etc., all need support snmp protocol naturally.

Along with the extensive use of SNMP, all to support SNMP Agent in the communication equipment side, so that snmp management station (SNMP Manager) manages communication equipment.SNMP Agent is the software module that resides on the communication equipment, accept the webmaster operation requests that SNMP Manager sends, and should ask to ask for management information or carry out corresponding operating to other protocol module, carry out corresponding bookkeeping, and SNMP Agent also reports the current state information of managed devices to SNMP Manager.

Fig. 1 is in the SNMP V1 version, carries out the schematic diagram of message interaction between SNMP Manager and the SNMP Agent, and for other versions such as the V2c among the SNMP, V3, the flow process of message interaction flow process and SNMP V1 version is similar.SNMP Manager sends the request that comprises GetRequest, GetNextRequest, SetRequest through physical network to SNMP Agent, SNMP Agent is according to the request that receives, utilize the mib file in the MIB storehouse that the communication equipment of being managed is operated, then, SNMP Agent sends the result of GetResponse response to SNMP Manager return, and, SNMP Agent can also by send to SNMP Manager Trap with the state information notification of managed devices to SNMP Manager.Wherein, an above-mentioned mib file is exactly the description to a managed object set, in this set, defined the attribute such as name, identifier, type of each managed object, defined the needed notice of this set simultaneously, the different different incidents of notice representative take place, and have specified in the notice and will tell SNMP Manager the value of which managed object, and different mib files has been described different managed object set; Above-mentioned GetRequest, GetNextRequest, SetRequest, GetResponse and Trap are the protocol operations among the SNMP, and their implication is as follows:

GetRequest: be used to obtain the request message of specifying by the value of management variable;

GetNextRequest: be used for obtaining continuously one group of request message of being managed the value of variable;

SetRequest: the request message that is used to be provided with the managed object of appointment;

GetResponse: to obtaining/be provided with the request responding message;

Trap: the notice message, SNMP Agent initiatively reports the announcement information of SNMP Manager, and the state notifying of the managed object of being correlated with the current event of communication equipment and when incident takes place is given SNMP Manager.

This shows that SNMP Agent need have corresponding processing code, thereby support above-mentioned GetRequest, GetNextRequest, SetRequest, GetResponse and Trap operation.Current, adopt mib compiling device to generate above-mentioned processing code as SNMP Agent aid.SNMP Agent can generate some automatically and handle code, for the developer takes out some data operating interfaces, shielded the detail of snmp protocol, make the developer under the situation that SNMP is not understood in depth, develop high-quality SNMP Agent in the short period of time and handle code, the processing code that utilizes the mib compiling device to generate automatically mainly contains the following aspects:

1, MIB tree C file: tree structure has been adopted in the definition of MIB, and it is exactly the form of one tree that all managed objects string together, and each managed object all has a position in tree, and this position can identify out, is called the identifier of managed object; During managed object of SNMP Manager operation, be to be which managed object by specifying its position in tree to indicate.MIB tree C file is articulated in SNMP Agent, is which managed object so that SNMP Agent can parse by identifier;

2, the Get/GetNext/Set protocol operation of Get/GetNext/Set handling process C file: SNMP is to concrete managed object, all to develop processing code to the managed object that defines in each mib file to the Get/GetNext/Set request message, this work has repeatability, and needs the developer familiar to snmp protocol.For reducing development difficulty, improve the speed of exploitation, can extract the general character in the processing code of Get/GetNext/Set request message, and generate with the mib compiling device; The Get/GetNext/Set handling process C file that the mib compiling device generates has automatically been contained the processing to all managed objects that define in the mib file, shield snmp protocol and handled details, only reserve some concrete data manipulation functions and fill realization to the developer, these concrete data manipulation functions are realized because of concrete application different, need handle according to the situation of using defined;

3, notice transmission interface C file: though different notice content differences, but the process that sends a notice is the same, send the processing code so also can generate notice automatically with the mib compiling device, the mib compiling device all generates a notice transmission interface function to each notice that defines in the mib file, the managed object that defines in the notice imports into as notice transmission interface function parameters, different notice transmission interfaces have different number of parameters, notice transmission interface function receives uses the parameter of being imported into, to finish the inspection of the managed object that notice is comprised in the message and to the packing of notice message, coding, processes such as transmission, at the description of above-mentioned message, above-described notice is the Trap message in the above-mentioned message;

After adopting the mib compiling device, the C file that the mib compiling device is generated compiles, and generates the program among the SNMP Agent, thereby finishes the development process of SNMP Agent.

Below in conjunction with an instantiation, the development approach that realizes SNMP Agent in the prior art is described.

Suppose that SNMP Agent has supported MIB1, MIB2 and MIB3, SNMP Agent needs further to support MIB4 now, referring to shown in Figure 2, realizes in the prior art that the process of SNMP Agent exploitation specifically may further comprise the steps:

A, all mib files of specifying SNMP Agent to be supported: MIB1, MIB2, MIB3 and MIB4, generate new MIB tree file with the mib compiling device, replace original MIB tree file with this newly-generated MIB tree file;

B, appointment MIB4 file use the mib compiling device to generate the Get/GetNext/Set handling process C code that MIB4 is handled, and generate the notice transmission interface processing C code to the MIB4 processing, to support Trap and GetResponse operation;

C, write concrete data manipulation function, the processing code described in the filling step B according to concrete application of MIB4;

D, with newly-generated MIB tree file with handle code and the binding of administration agent core code, just can generate the abundanter SNMP Agent of MIB characteristic and handle code, wherein, the administration agent core code provides the basic support that snmp protocol is handled, it is the basis of whole administration agent, handle code after carrying out binding, compile, generate the new administration agent program of supporting MIB4 by the C compiler.

Wherein, among the above-mentioned steps B, the mib compiling device all can generate a notice message transmission interface to each notice that defines in the mib file, the object of definition defined packing and sends to webmaster by snmp protocol during notice message transmission interface will be notified, and the notice message transmission interface transaction module of its generation as shown in Figure 3;

As can be seen, before the call notification transmission interface, need to provide local address, public realm name, object value from the notice message transmission interface model shown in Figure 3.Wherein, local address is the address of SNMP Agent; Object value is the value of the object in the notice definition; Public realm name is a notion among the SNMPv1/v2c, be similar to password, use it to do common discriminating, need be bundled in the message of SNMPv1/v2c, because SNMPv3 has strengthened the fail safe of whole agreement, introduced new notion and do not re-use the public domain name in message, therefore, this notice transmission interface only is applicable to SNMPv1/v2c.

The message format of SNMPv1/v2c is the same, all is made up of version number, public realm name and snmp protocol data cell (PDU) three parts.SNMP PDU has specified protocol operation type (GetRequest, GetNextRequest, SetRequest, GetResponse or Trap), and the managed object that will obtain or be provided with tabulation.The notification type that is provided in SNMPv1 is TRAP, and SNMPv2 has expanded a kind of new notification type SNMPv2-Trap on the basis of SNMPv1, these two kinds of notices belong to different protocol operations in SNMP, the PDU form difference that is adopted need be according to PDU form packing separately.These two kinds of notices are presented as respectively in the definition of mib file and adopt TRAP-TYPE and NOTIFICAITON-TYPE to define, the mib compiling device is by being that TRAP-TYPE definition or NOTIFICATION-TYPE definition generate different notice transmission interface functions in the identification mib file, according to message format packing separately.In the SNMP of reality Agent uses, sending according to any notification type is to determine according to current snmp protocol version, that SNMPv1 uses is TRAP, that SNMPv2c/v3 uses is SNMPv2-Trap, if SNMP Agent supports above-mentioned three versions of SNMP, then determine the type of notice according to the current configuration of notice, like this, just need be to twice of the definition of the notice in the mib file, once define with TRAP-TYPE, another time is with the NOTIFICATION-TYPE definition, to generate two kinds of different notice transmission interface functions for routine call.According to above-mentioned narration, can obtain, before call notification transmission interface function, also need the developer to do following coding:

1, obtains local address;

2, obtain public realm name;

3, judge current snmp protocol version information and notice configuration information, call any notice transmission interface function with decision;

Before calling each notice transmission interface function, all need three above-mentioned codings of developer oneself exploitation, workload is bigger, and, increasing under the situation that SNMP v3 is supported, because notice transmission interface function used parameter can be more, concern also more complicatedly, the work of being done before calling the transmission interface function will be more.

As seen, the prior art of foregoing description has following shortcoming:

1, all mib files must be compiled together and output on MIB tree file, this will cause MIB tree file very big, and some compiler is not supported the compiling of big file; Increase or deletion simultaneously, also be unfavorable for the reduction of module: if to the support of a MIB, must generate MIB with the compiling of mib compiling device again and set file;

2, the notice transmission interface is not supported SNMPv3, and autgmentability and maintainability are all bad, and it is bigger to send function used parameter and agreement correlation, need appointment parameter and the content relevant with snmp protocol, developer's workload is big, is unfavorable for control and expansion in management.

Summary of the invention

In view of this, main purpose of the present invention is to provide the development approach of a kind of SNMP Agent, this method supports different MIB defined file compilings to output on the different MIB tree files, the too big problem of file when having avoided compiling, and strengthen the tailorability of MIB by the MIB macro switch; By supporting more independently to notify the notice transmission interface model of transmission interface, not be used in and carry out any and the processing snmp protocol correlation before the notice transmission interface function, thereby reduced developer's workload.

The invention discloses a kind of development approach of supporting the administration agent (SNMP Agent) of Simple Network Management Protocol, it is characterized in that this method may further comprise the steps:

Steps A: management information bank (MIB) compiler generates MIB tree file, Get/GetNext/Set handling process file separately and notifies the transmission interface file at the mib file of each appointment respectively;

Step B: the low layer data operations function that is reserved in the Get/GetNext/Set handling process file that generates in the steps A is programmed, the code of this handling process is additional complete;

Step C: MIB subtree and Get/GetNext/Set handling process in each MIB tree file that is generated in the steps A are joined among the SNMP Agent, directly call the function in the corresponding notice transmission interface file in the place of needs transmission notice;

Step D: compiler with execution in step C after resulting processing code and SNMP Agent core code carry out binding, compiling generates SNMP Agent program then.

Wherein, generating MIB tree file described in the steps A comprises:

The mib compiling device is that the mib file of each appointment generates a static subtree and the pairing subtree loading function of this static state subtree.

Wherein, this method further is included in the head and tail generation macro switch of described static subtree.

Wherein, described in the step C each MIB subtree joined among the SNMP Agent and comprises:

Subtree loading function in described each MIB tree file is joined in the principal function of SNMP Agent.

Each Get/GetNext/Set handling process that wherein, will generate described in the step C joins among the SNMPAgent and comprises:

Main entrance function in described each Get/GetNext/Set handling process file is registered to SNMP Agent.

Wherein, described notice transmission interface function generates the processing code of realizing following steps after carrying out the described compiling of step D:

Step D1:

The content of the managed object that the notice transmission interface will report directly sends to the notice control centre of SNMP Agent;

Step D2:

Notice control centre receives the data that the notice transmission interface is brought, and checks SNMP Agent present configuration information, according to the version structure notification message of this configuration information, encodes and sends to and dispose notification received SNMP Manager.

As seen, the present invention has following beneficial effect:

1, allows different mib files to output in the different MIB tree files, reduce MIB tree file size, the file size problem in the time of needn't worrying to compile again; Simultaneously each MIB tree is increased the compiling macro switch, be convenient to the reduction of MIB.

2, support more independently to notify transmission interface, only need to specify the data message that will report management work station, handle relevant problem with snmp protocol and need not consider.

Description of drawings

Fig. 1 is in the SNMP V1 version, carries out the schematic diagram of message interaction between SNMP Manager and the SNMP Agent.

Fig. 2 is a SNMP Agent development process schematic diagram in the prior art.

Fig. 3 is the schematic diagram of notice message transmission interface transaction module in the prior art.

Fig. 4 is SNMP Agent development process schematic diagram among the present invention.

Fig. 5 sets the structural representation of file for the MIB that generates among the present invention.

Fig. 6 is the notice transmission interface model schematic diagram among the present invention.

Embodiment

The present invention is the development approach of a kind of SNMP Agent, and this method can be set file at the MIB that different mib files generates separately, supports more independently to notify transmission interface, only needs to specify the content of the managed object that will notify webmaster to get final product.

Describe the present invention below in conjunction with accompanying drawing.

Referring to SNMP Agent development model shown in Figure 4, the present invention realizes that the development approach of SNMP Agent may further comprise the steps:

Steps A: the mib file of specifying SNMP Agent to support, at the mib file of these appointments, the mib compiling device generates each MIB that specifies mib file tree file, Get/GetNext/Set handling process C file and notice transmission interface C file respectively; Adopt the C language in the embodiment of the invention, in other embodiments of the invention, also can adopt other programming language to realize the present invention;

Step B: the low layer data operations function that is reserved in the Get/GetNext/Set handling process C file that generates in the steps A is programmed, replenish the whole C code complete;

Step C: MIB subtree in each MIB tree file that is generated in the steps A and the handling process in the Get/GetNext/Set handling process C file are joined among the SNMP Agent, specifically comprise:

Subtree loading function in each MIB tree file that generates in the steps A is joined in the principal function of SNMPAgent, thereby the MIB subtree is joined among the SNMP Agent, make SNMPAgent to inquire defined object in each mib file according to the subtree loading function;

Main entrance function in each Get/GetNext/Set handling process C file that is generated in the steps A is registered to SNMP Agent; By registering to SNMP Agent, make SNMP Agent obtain for the pairing processing function of the mib file of an appointment, when SNMP Agent receive that SNMP Manager sends to the Get/GetNext/Set request of some objects the time, SNMP Agent can be according to log-on message, find and the corresponding processing function of this object, and finish operations such as obtaining or be provided with this object by this processing function;

Step D: the local directly call notification transmission interface function that sends notice at needs;

Step e: the C compiler compiles processing code in the file that generates in the above-mentioned steps and the binding of SNMP Agent core code then, generates SNMP Agent program.

Below above-mentioned steps is illustrated respectively:

In steps A, referring to shown in Figure 5, the MIB tree file that is generated comprises a static subtree and the pairing subtree loading function of this static state subtree, and with the MIB macro switch MIB being set file at the head and tail of each MIB tree file comprises, when SNMP Agent need support this MIB tree file, the macro switch of this MIB tree file is opened, carry out binding with remaining MIB tree file, after system moves, call the loading function of each MIB subtree successively, make the synthetic MIB of each MIB subtree set; Defined static subtree comprised each object in the MIB defined file name, identifier, type, access rights and with information such as other relation between objects, corresponding processing function; The function of described static subtree loading function is to specify the subtree head pointer that will load, and this subtree is loaded on the main tree of SNMP Agent, so that SNMP Manager inquiry and configuration; Wherein, in embodiments of the present invention, each MIB subtree adopts different MIB macro switches, this macro switch is opened, the MIB subtree that then has this macro switch promptly is loaded into SNMP Agent, and this macro switch is closed, and the MIB subtree that then has this macro switch just can not be loaded into SNMP Agent;

By steps A, the mib compiling device generates a static subtree to each mib file, and a MIB tree that is generated in the prior art is realized in the mode that generates some static MIB subtrees in the present invention, thereby the MIB that has reduced to be generated sets the size of file;

In step B, finish by the developer for the programming that low layer data operations function is carried out.Each object in each mib file has all been stipulated its characteristic in mib file when definition, and in mib file, reserve corresponding low layer data operations function according to the characteristic of this regulation, should not comprise actual content of operation in the low layer data operations function, in step B, the developer need define according to concrete MIB and realize these low layer data operations functions, to finish the function of obtaining, being provided with to the object that defined in the mib file of appointment; For instance, in the time of when an object is set, need carrying out a kind of concrete action, the programming that need hang down the layer data operations function according to this concrete action by the developer, realizing by this function and should specifically move, and above-mentioned this processing to be the mib compiling device can not generate automatically;

In step D, adopt notice transmission interface model shown in Figure 6 to carry out the exploitation of SNMP Agent, for the function of each the notice transmission interface in this model, after compiling, its structure notifier processes code and the process that sends to SNMP Manager are:

Step D1:

The content of the managed object that the notice transmission interface will report directly sends to the notice control centre of SNMP Agent, and control centre handles the work relevant with snmp protocol according to the protocol version of the current support of SNMP Agent with current configuration by notice;

Step D2:

Notice control centre receives the data that the notice transmission interface is brought, and checks SNMP Agent present configuration information, if be SNMPv1, then according to SNMPv1-TRAP PDU and the packing of SNMPv1 message format; If be SNMPv2, with SNMPv2-TRAP and the packing of SNMPv2 message format; If be SNMPv3, then also to add the discriminating enciphered message that needs, with SNMPv2-TRAP and the packing of SNMPv3 message format; If support a plurality of SNMP versions, then adopt which kind of notification type will see what the notice configuration of current SNMP Agent is, the information that needs during packing all obtains from current configuration information, to carry out the inspection of agreement regulation simultaneously to notification data, will construct good notification message coding then and send to and dispose notification received SNMP Manager;

The benefit that adopts above-mentioned notice transmission interface model to carry out the exploitation of SNMP Agent is: at first, before sending function, notice do not need to do any work, directly calling this function gets final product, secondly, when SNMPAgent supports new SNMP version, the notice transmission interface helps expansion and makes change amount minimum: though can call in a lot of places, but because it and protocol-independent, so the place of call notification transmission interface is without any need for change, only need amendment advice control centre, make it support that new snmp protocol version gets final product.

The above only is preferred embodiment of the present invention, and is in order to restriction the present invention, within the spirit and principles in the present invention not all, any modification of being done, is equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims

1, a kind of development approach of supporting the administration agent SNMP Agent of Simple Network Management Protocol is characterized in that this method may further comprise the steps:

Steps A: management information bank mib compiling device generates MIB tree file, Get/GetNext/Set handling process file separately and notifies the transmission interface file at the mib file of each appointment respectively;

2, method according to claim 1 is characterized in that generating described in the steps A MIB tree file and comprises:

3, method according to claim 2 is characterized in that this method further is included in the head and tail generation macro switch of described static subtree.

4, method according to claim 2 is characterized in that described in the step C each MIB subtree joined among the SNMP Agent and comprises:

5, method according to claim 1 is characterized in that each Get/GetNext/Set handling process that will generate described in the step C joins among the SNMP Agent to comprise:

6, method according to claim 1 is characterized in that described notice transmission interface function after carrying out the described compiling of step D, generates the processing code of realizing following steps:

Step D1:

Step D2: