H3C XE 200/2000 IP, Operation Manual

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Operation Manual – System Management
H3C XE 200/2000 IP PBX
Chapter 7 SNMP Configuration
7-1
Chapter 7 SNMP Configuration
7.1 SNMP Overview
7.1.1 Introduction to SNMP
Simple network management protocol (SNMP) is a widely used industry standard. Its
purpose is to ensure the transmission of management information between any two
points so that the network administrator can retrieve the information at any point on the
network and perform appropriate modification, troubleshooting, fault diagnosis, and
capacity planning and reporting. It adopts polling mechanism and offers the most
essential functionality set, so it is appropriate for networks of high speed and low cost.
The only requirement of unacknowledged transport layer protocol UDP makes it widely
supported.
Structurally, SNMP is divided into two parts: NMS (network management station) and
Agent. The NMS is a workstation running the client programs. The commonly used
network management platforms are Sun NetManager and IBM NetView. The Agent is
server-side software running on network devices. The information exchange between
NMS and Agent is performed by the following way: The NMS sends packets of
GetRequest, GetNextRequest, GetBulkRequest, and SetRequest to the Agent. Once
the Agent receives request packets from the NMS, it performs Read or Write operation
on management variables according to the type of the packets and generate Response
packets and return it to the NMS. On the other hand, if any exception happens to the
device, like a warm/cold restart, the Agent also sends a trap packet to the NMS on its
own initiative for an event report.
7.1.2 SNMP Versions and MIBs Supported
The managed objects in the device are described with management variables in SNMP
packets. In order to identify a managed object uniquely in the device, SNMP uses a
hierarchical naming convention to distinguish different managed objects. The
hierarchical structure is like a tree with its nodes representing managed objects. Each
node is identified uniquely by the path from the root. See Figure 7-1 .