Cisco Catalyst 2960 Series, Configuration Manual

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4 The get-bulk command only works with SNMPv2 or later.
SNMP Agent Functions
The SNMP agent responds to SNMP manager requests as follows:
•
Get a MIB variable
—
The SNMP agent begins this function in response to a request from the NMS. The
agent retrieves the value of the requested MIB variable and responds to the NMS with that value.
•
Set a MIB variable
—
The SNMP agent begins this function in response to a message from the NMS.
The SNMP agent changes the value of the MIB variable to the value requested by the NMS.
The SNMP agent also sends unsolicited trap messages to notify an NMS that a significant event has occurred
on the agent. Examples of trap conditions include, but are not limited to, when a port or module goes up or
down, when spanning-tree topology changes occur, and when authentication failures occur.
Related Topics
Disabling the SNMP Agent, on page 452
Monitoring SNMP Status, on page 467
Setting the Agent Contact and Location Information, on page 464
SNMP Community Strings
SNMP community strings authenticate access to MIB objects and function as embedded passwords. In order
for the NMS to access the switch, the community string definitions on the NMS must match at least one of
the three community string definitions on the switch.
A community string can have one of the following attributes:
•
Read-only (RO)
—
Gives all objects in the MIB except the community strings read access to authorized
management stations, but does not allow write access.
•
Read-write (RW)
—
Gives all objects in the MIB read and write access to authorized management stations,
but does not allow access to the community strings.
• When a cluster is created, the command switch manages the exchange of messages among member
switches and the SNMP application. The Network Assistant software appends the member switch number
(@esN, where N is the switch number) to the first configured RW and RO community strings on the
command switch and propagates them to the member switches.
Related Topics
Configuring Community Strings, on page 454
SNMP MIB Variables Access
An example of an NMS is the Cisco Prime Infrastructure network management software. Cisco Prime
Infrastructure 2.0 software uses the switch MIB variables to set device variables and to poll devices on the
network for specific information. The results of a poll can be displayed as a graph and analyzed to troubleshoot
internetworking problems, increase network performance, verify the configuration of devices, monitor traffic
loads, and more.
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
449
Information About SNMP