1-11 SNMP ConfigurationWhen configuring SNMP, go to these sections for information you are interested in:z SNMP Overviewz SNMP Configurationz Configuring SNMP Loggingz Configuring SNMP Trapz Displaying and Maintaining SNMPz SNMPv1/SNMPv2c Configuration Examplez SNMPv3 Configuration Examplez SNMP Logging Configuration ExampleSNMP OverviewSimple Network Management Protocol (SNMP) offers the communication rules between amanagement device and the managed devices on the network; it defines a series of messages,methods and syntaxes to implement the access and management from the management device to themanaged devices. SNMP has the following characteristics:z Automatic network management: SNMP enables network administrators to search and modifyinformation, find and diagnose network problems, plan for network growth, and obtain reports onnetwork nodes.z SNMP shields physical differences between various devices and thus realizes automaticmanagement of products from various vendors. Offering only the basic set of functions, SNMPmakes the management tasks independent of both the physical features of the managed devicesand the underlying networking technologies. Thus, SNMP achieves effective management ofdevices from different vendors, especially in small, high-speed and low-cost networkenvironments.SNMP MechanismAn SNMP-enabled network comprises a Network Management Station (NMS) and agents.z An NMS is a station that runs the SNMP client software. It offers a user-friendly interface,facilitating network administrators to perform most network management tasks.z An agent is a program resides in the device. It receives and handles requests sent from the NMS.Only under certain circumstances, such as interface state change, will the agent inform the NMS.An NMS is a manager in an SNMP enabled network, whereas agents are managed by the NMS. TheNMS and agents exchange management information through the SNMP protocol.SNMP provides the following four basic operations:z Get operation: The NMS gets the value of one or more objects of the agent.z Set operation: The NMS can reconfigure the value of one or more objects in the agent MIB(Management Information Base) by means of this operation.z Trap operation: The agent sends traps to the NMS through this operation.
