Snmp Configuration; Snmp Overview; Snmp Operation Mechanism; Snmp Versions - H3C S3100 Series Operation Manual

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SNMP Configuration

SNMP Overview

The simple network management protocol (SNMP) is used for ensuring the transmission of the
management information between any two network nodes. In this way, network administrators can
easily retrieve and modify the information about any node on the network. In the meantime, they can
locate faults promptly and implement the fault diagnosis, capacity planning and report generating.
As SNMP adopts the polling mechanism and provides basic function set, it is suitable for small-sized
networks with fast-speed and low-cost. SNMP is based on user datagram protocol (UDP) and is thus
widely supported by many products.

SNMP Operation Mechanism

SNMP is implemented by two components, namely, network management station (NMS) and agent.
An NMS can be a workstation running client program. At present, the commonly used network
management platforms include QuidView, Sun NetManager, IBM NetView, and so on.
Agent is server-side software running on network devices (such as switches).
An NMS can send GetRequest, GetNextRequest and SetRequest messages to the agents. Upon
receiving the requests from the NMS, an agent performs Read or Write operation on the managed
object (MIB, Management Information Base) according to the message types, generates the
corresponding Response packets and returns them to the NMS.
When a network device operates improperly or changes to other state, the agent on it can also send
trap messages on its own initiative to the NMS to report the events.

SNMP Versions

Currently, SNMP agent on a switch supports SNMPv3, and is compatible with SNMPv1 and SNMPv2c.
SNMPv3 adopts user name and password authentication.
SNMPv1 and SNMPv2c adopt community name authentication. The SNMP packets containing invalid
community names are discarded. SNMP community name is used to define the relationship between
SNMP NMS and SNMP agent. Community name functions as password. It can limit accesses made by
SNMP NMS to SNMP agent. You can perform the following community name-related configuration.
Specifying MIB view that a community can access.
Set the permission for a community to access an MIB object to be read-only or read-write.
Communities with read-only permissions can only query the switch information, while those with
read-write permission can configure the switch as well.
Set the basic ACL specified by the community name.

Supported MIBs

An SNMP packet carries management variables with it. Management variable is used to describe the
management objects of a switch. To uniquely identify the management objects of the switch, SNMP
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