What Is SNMP Huawei

An SNMP system consists of four key components: network management system (NMS), SNMP agent, managed object, and management information base (MIB). The NMS manages network elements on a network.

Each managed device contains an SNMP agent process, a MIB, and multiple managed objects. The NMS interacts with the SNMP agent on a managed device. When receiving an instruction from the NMS, the SNMP agent performs operations in the MIB on the managed device.

Figure 1-1 Components in an SNMP system

NMS
The NMS is a network manager that uses SNMP to manage and monitor network devices. The NMS software runs on NMS servers to implement the following functions:

* Sends requests to SNMP agents on managed devices to query or modify variables.

* Receives SNMP traps from SNMP agents on managed devices to learn the device status.

SNMP Agent
An SNMP agent is a process running on a managed device. It maintains data on the managed device, responds to requests from the NMS, and returns management data to the NMS. * Upon receiving a request from the NMS, the SNMP agent performs the required operation in the MIB and sends the operation result to the NMS.

* If a fault or event occurs on a managed device, the SNMP agent sends an SNMP trap containing the current device status to the NMS.

Managed Object
A managed object is an object to be managed on a network device. A managed device may contain multiple managed objects, for example, a hardware component and parameters configured for the hardware or software (such as a routing protocol).

MIB
A MIB contains the variables that a managed device maintains. The MIB defines the attributes of the managed device, including the name, status, access rights, and data type of managed objects. The MIB can be regarded as an interface between the NMS and SNMP agent. Through this interface, the NMS queries and sets the variables maintained by a managed device.

A MIB uses a tree structure to store data, as shown in Figure 1-2. A tree node indicates a managed object, which is uniquely identified by a path starting from the root. This path is called an object identifier (OID). For example, the OID of system is 1.3.6.1.2.1.1, and the OID of interfaces is 1.3.6.1.2.1.2.

A subtree can be identified by the OID of the root node of the subtree. For example, the OID of the subtree with private as the root node is the OID of private, that is, {1.3.6.1.4}.

Figure 1-2 OID treeYou can specify the MIB objects that the NMS can access in MIB views. A MIB view is a subset of a MIB. You can set the status of objects in a MIB view to exclude or include. exclude indicates that the current view does not contain all nodes of the MIB subtree. include indicates that the current view contains all nodes of the MIB subtree.