CHAPTER
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Catalyst2950 and Catalyst2955 Switch Software Configuration Guide
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Configuring SNMP
This chapter describes how to configure the Simple Network Management Protocol (SNMP) on your
Catalyst 2950 o r Catalyst 2955 switch.
Note For complete syntax and usage information for the commands used in this chapter, refer to the 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 28-1
Configuring SNMP, page 28-5
Displaying SNMP Status, page 28-16

Understanding SNMP

SNMP is an application-layer protocol that provides a message format for communication betwee n
managers and agents. The SNMP system consists of a n SN M P m an ager, an S NMP agen t , and a M I B.
The SNMP manager can be part of a network management system (NMS) such as CiscoWorks. The agent
and MIB reside on the switch. To configure SNMP on the switch, you define the relationshi p bet we en
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 managers 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 information about these topics:
SNMP Versions, page 28-2
SNMP Manager Functions, page 28-3
SNMP Agent Functions, page 28-4
SNMP Community Strings, page 28-4