Snmp Agent Functions; Snmp Community Strings; Using Snmp To Access Mib Variables - Cisco C3201FESMIC-TP= - 3201 Fast EN Switch Mobile Interface Card Expansion Module Software Configuration Manual

Simple Network Management Protocol

SNMP Agent Functions

The SNMP agent responds to SNMP manager requests as follows:
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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.

SNMP Community Strings

SNMP community strings authenticate access to MIB objects and function as embedded passwords. In
order for the NMS to access the WMIC, the community string definitions on the NMS must match at
least one of the three community string definitions on the WMIC.
A community string can have one of these attributes:
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Using SNMP to Access MIB Variables

An example of an NMS is the CiscoWorks network management software. CiscoWorks 2000 software
uses the 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.
As shown in
of certain events) to the SNMP manager, which receives and processes the traps. Traps are messages
alerting the SNMP manager to a condition on the network such as improper user authentication, restarts,
link status (up or down), MAC address tracking, and so forth. The SNMP agent also responds to
MIB-related queries sent by the SNMP manager in get-request, get-next-request, and set-request format.
Figure 1
SNMP manager
For information on supported MIBs and how to access them, see
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.
Read-only—Gives read access to authorized management stations to all objects in the MIB except
the community strings, but does not allow write access
Read-write—Gives read and write access to authorized management stations to all objects in the
MIB, but does not allow access to the community strings
Figure 1, the SNMP agent gathers data from the MIB. The agent can send traps (notification
SNMP Network
get-request, get-next-request,
NMS
get-bulk, set-request
get-response, traps
Network device
MIB
SNMP agent
Cisco 3200 Series Wireless MIC Software Configuration Guide
Understanding SNMP
"Supported MIBs."
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