Understanding Snmp - Cisco WS-C3550-12G Software Configuration Manual

Configuring SNMP
This chapter describes how to configure the Simple Network Management Protocol (SNMP) on your
switch.
For complete syntax and usage information for the commands used in this chapter, refer to the
Note
Catalyst 3550 Multilayer Switch Command Reference for this release and to the Cisco IOS
Configuration Fundamentals Command Reference for Release 12.1.
This chapter consists of these sections:
Understanding SNMP, page 18-1
•
• Configuring SNMP, page 18-4
Displaying SNMP Status, page 18-10
•

Understanding SNMP

SNMP is an application-layer protocol that provides a message format for communication between
SNMP managers and agents. The SNMP manager can be part of a network management system (NMS)
such as CiscoWorks. The agent and management information base (MIB) reside on the switch. To
configure SNMP on the switch, you define the relationship between the manager and the agent.
The SNMP agent contains MIB variables whose values the SNMP manager can request or change. A
manager can get a value from an agent or store a value into the agent. The agent gathers data from the
MIB, the repository for information about device parameters and network data. The agent can also
respond to a manager's requests to get or set data.
An agent can send unsolicited traps to the manager. Traps are messages alerting the SNMP manager to
a condition on the network. Traps can mean improper user authentication, restarts, link status (up or
down), MAC address tracking, closing of a TCP connection, loss of connection to a neighbor, or other
significant events.
This section includes this conceptual information:
• SNMP Versions, page 18-2
SNMP Manager Functions, page 18-2
•
SNMP Agent Functions, page 18-3
•
• SNMP Community Strings, page 18-3
Using SNMP to Access MIB Variables, page 18-3
•
78-11194-03
C H A P T E R
Catalyst 3550 Multilayer Switch Software Configuration Guide
18
18-1