Snmp Manager Functions; Snmp Agent Functions - Cisco 2950G 24 - Catalyst Switch Software Configuration Manual

Chapter 24 Configuring SNMP
Table 24-1 SNMP Security Models and Levels
Model Level
SNMPv1 noAuthNoPriv
SNMPv2C noAuthNoPriv
SNMPv3 noAuthNoPriv
SNMPv3 authNoPriv
You must configure the SNMP agent to use the SNMP version supported by the management station.
Because an agent can communicate with multiple managers, you can configure the software to support
communications with one management station using the SNMPv1 protocol, one using the SNMPv2C
protocol and another using SNMPv3.

SNMP Manager Functions

The SNMP manager uses information in the MIB to perform the operations described in
Table 24-2 SNMP Operations
Operation
get-request
get-next-request
get-bulk-request
get-response
set-request
trap
1. With this operation, an SNMP manager does not need to know the exact variable name. A sequential search is performed to
2. The get-bulk command only works with SNMPv2 or later.

SNMP Agent Functions

The SNMP agent responds to SNMP manager requests as follows:
•
•
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.
78-14982-01
Authentication
Community string No
Community string No
Username
MD5 or SHA
Description
Retrieves a value from a specific variable.
Retrieves a value from a variable within a table.
2
Retrieves large blocks of data, such as multiple rows in a table, that would
otherwise require the transmission of many small blocks of data.
Replies to a get-request, get-next-request, and set-request sent by an NMS.
Stores a value in a specific variable.
An unsolicited message sent by an SNMP agent to an SNMP manager when some
event has occurred.
find the needed variable from within a table.
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.
Encryption Result
Uses a community string match for authentication.
Uses a community string match for authentication.
No Uses a username match for authentication.
No Provides authentication based on the HMAC-MD5
or HMAC-SHA algorithms.
Catalyst 2950 Desktop Switch Software Configuration Guide
Understanding SNMP
Table
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24-2.
24-3