ZyXEL Communications GS1510-16 -, Руководство пользователя

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Chapter 22 SNMP
GS1510 Series User’s Guide
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next figure illustrates an SNMP management operation. SNMP is only available if
TCP/IP is configured.
Figure 77 SNMP Management Model
An SNMP managed network consists of two main components: agents and a
manager.
An agent is a management software module that resides in a managed network
device (the Switch). 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 the device. Examples of variables
include number of packets received, node port status and so on. 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.
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:
Table 42 SNMP Commands
COMMAND DESCRIPTION
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.