JPH08293897A - Exclusive control system - Google Patents

Abstract

PURPOSE: To dispense with proceedings for setting a lock state as against a management table and setting a value as against the management table with it from a manager by way of an agent. CONSTITUTION: When the agent 4 generates (or erases) a management object 7 in (from) a management information base 3 based on an indication from one of the managers 1 and 2, an operation to write the value 1 (or the value 0) in the applying area of the management table 8 in the management information base 3 is executed at first. At this time, when the value of a writing destination is zero (or one) and the applying area value is changed, it is judged that there is no access from the other manager so that the corresponding management object is generated (or erased). When the value of the writing destination is one (or zero) even if the operation for writing th value 1 (or the value 0) in the applying area of the management table 8 is executed and he applying area value is not executed, it is judged that preceding access from he other manager is executed so that the processing is interrupted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a network management system for monitoring and controlling an information transmission system composed of a plurality of transmission devices, which receives an instruction from a manager among hierarchical network components. The present invention relates to an exclusive control method when an agent creates or deletes a line management object included in a transmission path management object.

[0002]

2. Description of the Related Art In a multi-manager environment in which a plurality of managers request a single agent to operate a management object, according to a conventional method, each corresponding area of a management table indicates lock or unlock. When the agent creates or deletes a management object by providing a lock status display flag, first changes the lock status of each applicable area from unlocked to locked before setting the value in the applicable area of the management table. In many cases, the method of setting the target value after doing is adopted.

[0003]

According to the above-mentioned prior art, in order to update the value of the management table associated with the generation or deletion of the management object, it is necessary to perform the inquiry processing of the lock state without fail. When creating or deleting a managed object that involves the process of rewriting a large number of areas, transmission and reception of messages between the manager and agent increases, and transmission efficiency declines. Also, both manager and agent have poor processing efficiency. Further, there is a drawback that extra system resources such as a disk and a memory are required to hold the lock state.

The object of the present invention is to eliminate the need for setting a lock state for a management table and setting a value for the management table accordingly, via a manager via an agent. Therefore, a system such as a memory for holding a lock state is required. It is to provide an exclusive control method that does not require extra resources.

[0005]

According to the present invention, a plurality of managers that perform management operations of management targets, a management information base that stores management objects that are management targets of the plurality of managers, and the plurality of managers A network management system in a multi-manager environment, which comprises an agent for accessing the management information base on behalf of a management operation instructed by In the above, the management information base manages the usage state of the resources required to generate the management object. Therefore, when one value is set in the area corresponding to the resources required to generate the management object, Is available and another value is set, it means that the corresponding resource is unavailable. The management table, the agent manages the state of the resources occupied by the management objects by the management table, and each of the plurality of managers copies the management table with the same content as the content of the management table. When the agent generates a management object based on an instruction from one of the plurality of managers, when the management table has one area corresponding to the resource required to generate the management object, Performs a write operation of the other value to the area of the management table, and if the value of the area is changed by this operation, it judges that there is no preceding access from the other manager to the area. , When the corresponding managed object generation is executed and the management object generation operation is completed, the request source Even if the manager is notified of the successful creation of the managed object, the management table copy owned by each manager is made to match the management table owned by the agent, and the write operation of the other value to the area is performed, the value of the area If the change is not made, it is judged that the preceding area is being accessed by another manager, and the exclusive control method characterized by interrupting the processing is obtained.

Here, if the agent does not change the value of the area even after performing the writing operation of the other value to the area, the agent makes prior access to the area by another manager. It is judged that
While interrupting the processing, the manager of the request source is notified of the failure of the managed object generation.

Further, according to the present invention, a plurality of managers that perform management operations of management targets, a management information base that stores management objects that are management targets of the plurality of managers, and management instructed by the plurality of managers In the network management system of a multi-manager environment, the management information comprising: an agent acting on behalf of and accessing the management information base, wherein the plurality of managers requests a single operation of the management object to the single agent. The base manages the usage status of the resources required to generate the management object. Therefore, when a value is set in the area corresponding to the resources required to generate the management object, the corresponding resources are available. , When another value is set, it indicates that the corresponding resource is unavailable. The agent manages the state of the resource occupied by the management object by this management table, and each of the plurality of managers has a management table copy having the same contents as the contents of the management table. However, when the agent creates a management object based on an instruction from one of the plurality of managers, the area of the management table corresponding to the resource required for creating the management object is N (2).
In the case of the above integers), as long as the other value is written to each of the N areas of the management table, the value of each of the N areas is changed as a result. , It judges that each of the N areas is not precedently accessed by another manager, and performs the write operation of the other value to the next one of the N areas, thereby When all the values in the area have been changed, the corresponding managed object is created, and when the managed object creation operation is complete, the manager of the request source is notified of the successful creation of the managed object. ,
Even if the management table copy owned by each manager is matched with the management table owned by the agent, and the write operation of the other value to each of the N areas is performed, the value of each of the N areas is changed. When the above is not performed, it is determined that the preceding access from another manager is being performed on each of the N areas, and the exclusive control method characterized by interrupting the processing is obtained.

Here, if the agent does not change the value of each of the N areas even after performing the write operation of the other value to the N areas,
It is determined that each of the N areas is being pre-accessed by another manager, the processing is interrupted, and the value of each area whose value has already been changed is returned to the original value. Notify the manager that the managed object creation failed.

Further, according to the present invention, a plurality of managers that perform management operations of management targets, a management information base that stores management objects that are management targets of the plurality of managers, and management instructed by the plurality of managers In the network management system of a multi-manager environment, the management information comprising: an agent acting on behalf of and accessing the management information base, wherein the plurality of managers requests a single operation of the management object to the single agent. The base manages the usage status of the resources required to generate the management object. Therefore, when a value is set in the area corresponding to the resources required to generate the management object, the corresponding resources are available. , When another value is set, it indicates that the corresponding resource is unavailable. The agent manages the state of the resource occupied by the management object by this management table, and each of the plurality of managers has a management table copy having the same contents as the contents of the management table. However, when the agent deletes a management object based on an instruction from one of the plurality of managers, if there is one area in the management table corresponding to the resource required to delete the management object, If the one value is written to the area of the management table and the value of the area is changed by this operation, it is determined that there is no prior access from another manager to the area, and the action is taken. When the management object deletion is performed and the management object deletion operation ends, the requesting manager Notifying the success of the management object deletion, changing the value of the area even if the management table copy owned by each manager is made to match the management table of the agent and the operation of writing the one value to the area is performed. If the above is not performed, it is determined that the preceding access is being performed from another manager to the area, and the exclusive control method characterized by interrupting the processing is obtained.

Here, if the agent does not change the value of the area even after performing the write operation of the one value to the area, the agent accesses the area in advance by another manager. It is judged that
The process is interrupted, and the manager of the request source is notified of the failure to delete the managed object.

Further, according to the present invention, a plurality of managers that perform management operations of management targets, a management information base that stores management objects that are management targets of the plurality of managers, and management instructed by the plurality of managers In the network management system of a multi-manager environment, the management information comprising: an agent acting on behalf of and accessing the management information base, wherein the plurality of managers requests a single operation of the management object to the single agent. The base manages the usage status of the resources required to generate the management object. Therefore, when a value is set in the area corresponding to the resources required to generate the management object, the corresponding resources are available. , When another value is set, it indicates that the corresponding resource is unavailable. The agent manages the state of the resource occupied by the management object by this management table, and each of the plurality of managers has a management table copy having the same contents as the contents of the management table. However, when the agent deletes a management object based on an instruction from one of the plurality of managers, the management table area corresponding to the resource required to delete the management object is N (2).
In the case of the above integers), as long as the operation of writing the one value to each of the N areas of the management table is performed and thereby the value of each of the N areas is changed. , It judges that there is no prior access from other managers to each of the N areas, and performs the write operation of the one value to the next one of the N areas. When all the values in the area have been changed, the corresponding managed object deletion is executed, and when the management object deletion operation is completed, the manager of the request source is notified of the successful management object deletion. ,
Even if the management table copy owned by each manager is matched with the management table owned by the agent, and the write operation of the one value to each of the N areas is performed, the value of each of the N areas is changed. If the above is not performed, it is determined that the preceding access is being performed from another manager to each of the N areas, and the exclusive control method characterized by interrupting the processing is obtained.

Here, when the agent does not change the value of each of the N areas even after performing the write operation of the one value to the N areas,
It is determined that each of the N areas is being pre-accessed by another manager, the processing is interrupted, and the value of each area whose value has already been changed is returned to the original value. Notify the manager that the managed object deletion failed.

[0013]

As described above, in the present invention, the lock state display flag corresponding to each area of the management table is not provided, and when an agent creates a management object based on an instruction from a certain manager, first, An operation of writing the other value (for example, the value 1) to the corresponding area of the management table is performed, and at this time, the value of the writing destination is the one value (for example, the value 0), and the value of the corresponding area is changed. If it is determined that there is no access from another manager, the processing is continued, the value of the writing destination is the other value (for example, value 1), and the value of the corresponding area is not changed. Judges that the preceding access is being made from another manager and interrupts the processing.

As a result, the manager does not need to issue another request for generation of the relevant managed object to the agent after checking the lock state display flag and the value stored in the management table one by one, and confirming the value. Transmission processing efficiency between agents is improved.

Similarly, when the agent deletes a managed object based on an instruction from a manager, the operation of writing the one value (for example, the value 0) to the corresponding area of the management table is performed. When the value is the other value (for example, the value 1) and the value of the corresponding area is changed, it is determined that there is no access from another manager, the processing is continued, and the value of the writing destination is the above value. If the value is one value (for example, the value is 0) and the value of the corresponding area has not been changed, it is determined that the preceding access is being made by another manager, and the processing is interrupted.

It is possible to improve the transmission efficiency and the processing efficiency in the same manner as when the management object is generated.

When there are a plurality of corresponding areas corresponding to one management object, the agent repeats the above-mentioned processing a plurality of times, and when all the rewriting processing of the values held in the management table is completed without interruption, the corresponding management object When the generation or deletion is performed and this processing is completed normally, the success of the management object generation or deletion processing is notified to the request source manager.

This makes it possible to deal with a case where a plurality of management table areas are rewritten when one management object is generated.

In the middle of the rewriting process by the agent, if the interruption due to the preceding access from another manager is forced, the values of the respective areas already set are returned to the original values,
Notify the requesting manager that the management object creation or deletion process failed.

As a result, the consistency between the generation / deletion state of the management table and the management object is ensured.

[0021]

Next, an embodiment of the present invention will be described with reference to the drawings.

Referring to FIG. 1, a network management system to which the present invention is applied includes managers 1 and 2 each comprising a workstation and a management information base (MIB:
a mediation device (MD) 5 having a management information base) 3 and an agent 4, and a transmission device
(NE: network element) 6. In this network management system, there are two workstations as managers 1 and 2 which are the main bodies for managing the network, and the two managers 1 and 2 access the intermediary device 5 including one agent 4. It assumes a multi-manager environment. The agent 4 manages the management objects (MO: management
bject) 7 is operated according to the request from the manager 1 or 2. A management table 8 is stored in the management information base 3.

In the illustrated example, the agent 4 and the management information base 3 are provided in the intermediary device 5, but the agent 4 and the management information base 3 do not necessarily have to exist in the intermediary device 5, and for example, the transmission device 6 It may be deployed to.

Referring to FIG. 2, a managed object and management table 8 is shown. The managed object is a collection of managed objects 7-1 to 7-5. In the management table 8, when the corresponding area has a value of 1, it indicates that the time slot (TS) is already occupied.
A value of 0 in the corresponding area indicates that the time slot is still empty.

The management table 8 exemplifies an occupancy table of time slots (TS) included in a transmission path in a transmission device forming a leased line network, for example. That is, this management table 8 is 1.5
Assuming that a plurality of 64 Kbps lines are accommodated in the Mbps path, the management table owned by the 1.5 Mbps path is illustrated. In this case, the management table 8 is 1.5M
The status of the 64 Kbps line accommodated by the bps path (that is,
Occupancy of time slots) is managed.

2 and 3, the transmission path of 1.5 Mbps has a time slot of 64 Kbps as a TS.
It has 24 units of 1 to TS24. For example, TS1 is a 64 Kbps line, TS2 to TS7 is a 384 Kbps line, TS8 is a 64 Kbps line, TS18 to TS20 is a 192 Kbps line, and TS21 to TS23 is a 192 Kbps line.
Accommodates a ps line.

If a management object 7-4 or 7-5 for managing a 192 Kbps line is generated in the management information base 3 (FIG. 1), the line accommodating source of 1.5M is used.
In the management table 8 of the bps path, the value 1 is set in the management table area for three time slots (TS18 to TS20 or TS21 to TS23), and then the corresponding target management object 7-4 (MO4) or 7-5 is set.
(MO5) will be generated. Similarly, 64 Kbp
Management objects 7-1 (MO1) and 7 for managing the s line, 384 Kbps line, and 64 Kbps line
-2 (MO2) and 7-3 (MO3) are generated in the management information base 3, the management table 8 sets the value 1 in the management table areas of the time slots TS1, TS2 to TS7, and TS8. Therefore, the corresponding managed objects 7-1, 7-2, and 7-3 are generated.

FIG. 4 is a diagram in which essential parts of the network management system of FIG. 1 relating to the present invention are extracted. As shown in the figure
Each of the plurality of managers 1 and 2 has a copy of the management table in the management information base 3, and a request for generation / deletion of the management object 7 is made by copying the management table of each of the managers 1 and 2. Issue according to the content.

The management table 8 is positioned as a master in the system, and it is premised that requests issued from all managers 1 and 2 are always reflected in this management table 8.

Here, as shown in FIG. 5, the areas of the management table 8 are x1 to x24, and the areas x1 to x2.
It is assumed that each of 4 is set to the value 0. In the sequence described below, 64 Kbps (64 Kbps) from the manager 1 to the position of the time slot TS24 (FIG. 2).
s × 1) line is set, and a 1.5 Mbps line (64 Kbps × 24 line) that occupies the time slots TS1 to TS24 from the manager 2 is set behind the instruction from the manager 1.

First, the above conventional method will be described with reference to FIG.

The manager 1 refers to the copy of its own management table and recognizes that all the time slots TS are free. In the conventional method, the manager 1 then uses x2 to secure the time slot TS24.
Issue a request to the agent to lock area 4.

The agent requests the area x2 according to the request.
Locks 4 and responds to the manager 1 that it has processed normally.

In response to this response, the manager 1 requests the agent to set the content of the management table to "x24 (area corresponding to time slot TS24) = 1" in preparation for generating the management object (M0). Send to.

In response to this, the agent tries to set 1 in the corresponding area, but at this time, since the corresponding area in the management table is 0, it is judged that there is no access from another manager, Value 1 in the relevant area as requested
Set.

The manager 1 is notified by the agent that the reservation of this resource has been normally executed, and then 6
A management object generation request is transmitted to the agent in order to generate a management object (M0) for a 4 Kbps line.

After this, independently of the behavior of the manager 1,
The manager 2 refers to a copy of its own management table, recognizes that all the time slots TS are empty, and then creates a management object (M0) of a 1.5 Mbps line using the time slots TS1 to TS24. To lock each one in turn, and then
The operation of sequentially setting the value 1 is repeated.

In response to this, the agent first locks all the areas x1 to x24 corresponding to the time slot TS1 and then tries to set the value 1 when all the locks are completed. .

Since the areas x1 to x23 are not locked, it is judged that there is no access from another manager. However, the area x24 is already locked by the resource securing operation from the manager 1, Recognize that there is access from another manager and interrupt the processing here.

That is, it is recognized that the request from the manager 2 cannot be executed because the resource cannot be secured.

After this, the agent determines the areas x1 to x2.
For 3, unlock all locks. As a result, the management table returns to the state before the request from the manager 2 occurred.

Further, the resource securing failure notification sent from the agent allows the manager 2 to know that its request has ended abnormally.

After that, when a further time elapses and the management object generation request issued from the manager 1 is normally completed in the processing of the agent and below, the management object (M
O)) is normally generated, and the manager 1 recognizes that the request issued by the manager 1 has been normally completed.

As described above, in the conventional method, the manager locks the relevant area of the management table (MO) one by one, guards against access from other managers, and then sets the value in the management table. Write, all resources (in this case, time slot TS of accommodation path)
Since a management object (OS) generation request is sent at the time when the management object (OS) is secured, there is a drawback that the transmission efficiency between the manager and the agent and the processing efficiency in the manager / agent are poor.

In particular, when a management object (MO) that needs to secure a plurality of areas needs to be generated in the management table, the problem is large.

Next, a sequence example according to the method according to the embodiment of the present invention will be described with reference to FIG.

First, the manager 1 refers to the copy of the management table that it has, and checks all the time slots TS.
Recognize that it is vacant. In the present method, the manager 1 next secures the time slot TS24 by
The content of the management table is "x24 (time slot TS2
A request to set "area corresponding to 4) = 1" is sent to the agent.

In response to this, the agent tries to set 1 in the corresponding area, but at this time, since the corresponding area in the management table is 0, it is judged that there is no access from another manager, and the request is made. The value 1 is set in the corresponding area as per the above.

The manager 1 is notified by the agent that the reservation of this resource has been normally executed, and then 6
A management object generation request is transmitted to the agent in order to generate a management object (MO) of a 4 Kbps line.

After this, independently of the behavior of the manager 1,
After the manager 2 refers to the copy of the management table of its own and recognizes that all the time slots TS are vacant, in order to secure the time slots TS1 to 24, the contents of the management table are set to "x1 to x24 (time A request for "area corresponding to slots TS1 to TS24) = 1" is sent to the agent.

In response to this, the agent tries to set 1 to the corresponding area in order from the area x1 corresponding to the time slot TS1, but from the area x1 to the area x23, the corresponding area of the management table is 0. Since it has become
It is determined that there is no access from another manager, and the value 1 is set in the relevant area as requested.

However, the area x24 is already in the manager 1
Since the value is set to 1 by the resource securing operation from, it is recognized that there is an access from another manager,
The process is interrupted here.

That is, the request from the manager 2 cannot be executed because the resource cannot be secured.

Since the agent restores the state of the management table to the original state, the area x1 corresponding to the time slot TS1
In order from 0, 0 is set in the corresponding area. As a result, the area x1 to the area x23 are all 0 from the agent.
The management table is returned to the state before the request of the manager 2 is generated.

Further, the resource securing failure notification sent from the agent allows the manager 2 to know that its own request has terminated abnormally.

After that, when a further time elapses and the management object generation request issued from the manager 1 ends normally in the processing of the agent and below, the management object (MO) is normal to the manager 1 from the agent. Then, the manager 1 recognizes that the request issued by itself has been completed normally.

As described above, the present system enables efficient processing as compared with the conventional system.

[0058]

As described above, according to the present invention, it is not necessary to set the lock state of the management table and the setting of the value of the management table accompanying the setting via the agent from the manager, so that a large number of areas of the management table can be obtained. Even in the case of generating a management object that involves a process of rewriting a value, the processing efficiency does not deteriorate, and there is an effect that an extra system resource such as a memory is not required.

[Brief description of drawings]

FIG. 1 is a block diagram of a network management system to which the present invention is applied.

FIG. 2 is a block diagram illustrating a management object and a management table of the network management system of FIG.

FIG. 3 is a block diagram for explaining the management table of FIG.

FIG. 4 is a block diagram in which essential parts of the network management system of FIG. 1 according to the present invention are extracted.

FIG. 5 is a diagram used to describe a sequence of a conventional system and a system according to an embodiment of the present invention.

FIG. 6 is a diagram showing a sequence example of a system according to an embodiment of the present invention.

FIG. 7 is a diagram showing a sequence example of a conventional method.

[Explanation of symbols]

 1 Manager 2 Manager 3 Management Information Base (MIB) 4 Agent 5 Mediation Device 6 Transmission Device (NE) 7 Management Object (MO) 8 Management Table

Claims (8)

[Claims] 1. A plurality of managers that perform management operations of a management target, a management information base that stores management objects that are management targets of the plurality of managers, and a management operation designated by the plurality of managers on behalf of the managers. A network management system in a multi-manager environment, comprising: an agent for accessing the management information base, wherein the plurality of managers requests a single agent to operate a management object, wherein the management information base is a management object. In order to manage the usage status of the resources required to create a managed object, when one value is set in the area corresponding to the resource needed to create a managed object, the corresponding resource is available and another value is set. Management table that indicates that the corresponding resource is unavailable, The gent manages the state of the resource occupied by the managed object by this management table, each of the plurality of managers has a management table copy having the same content as the content of the management table, and the agent, When a management object is generated based on an instruction from one of the plurality of managers, if there is one area in the management table corresponding to the resource required to generate the management object, the area in the management table is the corresponding area. Write the other value to the
When the value of the area is changed as a result, it is determined that there is no prior access from other managers to the area, the corresponding managed object is created, and the management object creation operation ends. At that time, the manager of the request source is notified of the success of the management object generation, the management table copy owned by each manager is matched with the management table of the agent, and the other value is written to the area. Even if the value of the area is not changed, the exclusive control method is characterized in that it judges that the area is being pre-accessed by another manager and interrupts the processing. 2. The agent, if the value of the area is not changed even after performing the write operation of the other value to the area, prior access from another manager to the area is performed. The exclusive control method according to claim 1, wherein it is determined that the management object is being executed, and the processing is interrupted, and at the same time, the manager of the request source is notified of the failure of the management object generation. 3. A plurality of managers that perform management operations of management targets, a management information base that stores management objects that are management targets of the plurality of managers, and a management operation designated by the plurality of managers on behalf of the managers. A network management system in a multi-manager environment, comprising: an agent for accessing the management information base, wherein the plurality of managers requests a single agent to operate a management object, wherein the management information base is a management object. In order to manage the usage status of the resources required to create a managed object, when one value is set in the area corresponding to the resource needed to create a managed object, the corresponding resource is available and another value is set. Management table that indicates that the corresponding resource is unavailable, The gent manages the state of the resource occupied by the managed object by this management table, each of the plurality of managers has a management table copy having the same content as the content of the management table, and the agent, When a management object is generated based on an instruction from one of the plurality of managers, when the number of areas of the management table corresponding to the resources required to generate the management object is N (integer of 2 or more) , As long as the other value is written to each of the N areas of the management table, and thereby the value of each of the N areas is changed, It is judged that there is no previous access from another manager to the other area, and the other value is written to the next one of the N areas. When all the values of the N areas have been changed, the corresponding managed object is generated, and when the management object generation operation is completed, the generation of the managed object is successful in the requesting manager. Is notified and the management table copy owned by each manager is matched with the management table owned by the agent, and the write operation of the other value to each of the N areas is performed, If the respective values are not changed, it is determined that each of the N areas is being pre-accessed by another manager, and the processing is interrupted. . 4. If the agent does not change the value of each of the N areas even after performing the write operation of the other value to the N areas, the agent changes the N value.
It judges that each of these areas is being pre-accessed by another manager, interrupts processing, and restores the values of each area whose values have already been changed to the requesting manager. The exclusive control method according to claim 3, wherein a failure of management object generation is notified. 5. A plurality of managers that perform management operations of management targets, a management information base that stores management objects that are management targets of the plurality of managers, and the management operations designated by the plurality of managers are delegated. A network management system in a multi-manager environment, comprising: an agent for accessing the management information base, wherein the plurality of managers requests a single agent to operate a management object, wherein the management information base is a management object. In order to manage the usage status of the resources required to create a managed object, when one value is set in the area corresponding to the resource needed to create a managed object, the corresponding resource is available and another value is set. Management table that indicates that the corresponding resource is unavailable, The gent manages the state of the resource occupied by the managed object by this management table, each of the plurality of managers has a management table copy having the same content as the content of the management table, and the agent, When deleting a management object based on an instruction from one of the plurality of managers, if there is one area in the management table corresponding to the resource required to delete the management object, the area in the management table Write the above-mentioned one value to
If the value of the area is changed as a result, it is determined that there is no previous access to the area by another manager, the corresponding managed object is deleted, and the management object deletion operation ends. At that time, the manager of the request source is notified of the successful deletion of the managed object, and the management table copy owned by each manager is made to match the management table of the agent, and the one-value write operation to the area is performed. Even if the value of the area is not changed, the exclusive control method is characterized in that it judges that the area is being pre-accessed by another manager and interrupts the processing. 6. The agent, if the value of the area is not changed even after the write operation of the one value to the area is performed, prior access from another manager to the area is performed. The exclusive control method according to claim 5, wherein the process is interrupted when it is determined that the management object is deleted, and the manager of the request source is notified of the failure of deleting the managed object. 7. A plurality of managers that perform management operations of management targets, a management information base that stores management objects that are management targets of the plurality of managers, and a management operation designated by the plurality of managers on behalf of the managers. A network management system in a multi-manager environment, comprising: an agent for accessing the management information base, wherein the plurality of managers requests a single agent to operate a management object, wherein the management information base is a management object. In order to manage the usage status of the resources required to create a managed object, when one value is set in the area corresponding to the resource needed to create a managed object, the corresponding resource is available and another value is set. Management table that indicates that the corresponding resource is unavailable, The gent manages the state of the resource occupied by the managed object by this management table, each of the plurality of managers has a management table copy having the same contents as the contents of the management table, and the agent, When deleting a management object based on an instruction from one of the plurality of managers, if there are N (integer of 2 or more) areas in the management table corresponding to the resources required to delete the management object, , As long as the operation of writing the one value to each of the N areas of the management table is performed to change the value of each of the N areas, It is determined that there is no preceding access to another manager in the above, and the operation of writing the one value to the next one of the N areas is performed. When all the values of the N areas have been changed, the corresponding managed object is deleted, and when the management object deletion operation is completed, the management of the requesting manager succeeds in deleting the managed object. Is notified, and the management table copy owned by each manager is matched with the management table owned by the agent and the write operation of the one value to each of the N areas is performed, If the respective values are not changed, it is determined that each of the N areas is being pre-accessed by another manager, and the processing is interrupted. . 8. If the agent does not change the value of each of the N areas even after performing the write operation of the one value to the N areas, the agent changes the N value.
It judges that each of these areas is being pre-accessed by another manager, interrupts processing, and restores the values of each area whose values have already been changed to the requesting manager. The exclusive control method according to claim 7, wherein a failure in deleting the managed object is notified.