Huawei BM2022, Руководство пользователя

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Chapter 12 Maintenance
BM2022 Users Guide
173
SNMP
An SNMP managed network consists of two main types of component: agents and a manager.
Figure 92
SNMP Management Model
An agent is a management software module that resides in a managed device (the BM2022). An
agent translates the local management information from the managed device into a form
compatible with SNMP. The manager is the console through which network administrators perform
network management functions. It executes applications that control and monitor managed
devices.
The managed devices contain object variables/managed objects that define each piece of
information to be collected about a device. Examples of variables include such as number of
packets received, node port status etc. A Management Information Base (MIB) is a collection of
managed objects. SNMP allows a manager and agents to communicate for the purpose of accessing
these objects. The BM2022 supports MIB II that is defined in RFC-1213 and RFC-1215. The focus of
the MIBs is to let administrators collect statistical data and monitor status and performance.
SNMP itself is a simple request/response protocol based on the manager/agent model. The
manager issues a request and the agent returns responses using the following protocol operations:
Get - Allows the manager to retrieve an object variable from the agent.
GetNext - Allows the manager to retrieve the next object variable from a table or list within an
agent. In SNMPv1, when a manager wants to retrieve all elements of a table from an agent, it
initiates a Get operation, followed by a series of GetNext operations.
Set - Allows the manager to set values for object variables within an agent.
Trap - Used by the agent to inform the manager of some events.