1.1 Introduction to SNMP
SNMP provides a set of standard protocols for the communication between the network
management station (NM station) and devices, allowing the NM station to normally manage
devices and receive alarms reported by the devices.
1.1.1 SNMP Overview
Get and Set operations can be performed on a managed device that runs the SNMP agent to
manage device objects by NM stations These objects are uniquely identified in the Management
Information Base (MIB).
As network services develop, more devices are deployed on existing networks. The devices are
not close to the central equipment room where a network administrator works. When faults occur
on the remote devices, the network administrator cannot detect, locate or rectify faults
immediately because the devices do not report the faults. This affects maintenance efficiency
and greatly increases maintenance workload.
To solve this problem, equipment vendors have provided network management functions in
some products. These functions allow the NM station to query the status of remote devices, and
devices can send alarms to the NM station in the case of particular events.
SNMP operates at the application layer of the IP suite and defines how to transmit management
information between the NM station and devices. SNMP defines several device management
operations that the NM station can perform and allows devices to send alarms to notify the NM
station of device faults.
An SNMP-managed network consists of three components: NM station, agent, and managed
device. The NM station uses the MIB to identify and manage device objects. The operations
used for device management include GetRequest, GetNextRequest, GetResponse, GetBulk,
SetRequest, and notification from the agent to the NM station. The following sections give details
on the components, MIB, and operations.
SNMP Components
SNMP device management uses the following three components:
l
NM station: sends various query packets to query managed devices and receives alarms
from these devices.
l
Agent: is a network-management process on a managed device. An agent has the following
functions:
–
Receives and parses query packets sent from the NM station.
–
Reads or writes management variables based on the query type, and generates and sends
response packets to the NM station.
–
Sends an alarm to the NM station when triggering conditions defined on each protocol
module corresponding to the alarm are met. For example, the system view is displayed
or closed, or the device is restarted.
l
Managed device: is managed by an NM station and generates and reports alarms to the NM
station.
shows the relationship between the NM station and agent.
Huawei AR150&200 Series Enterprise Routers
Configuration Guide - Network Management
1 SNMP Configuration
Issue 02 (2012-03-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
2
