How to manage SNMP protocols

Next we will explain the SNMP protocol management. We all know that for the SNMP protocol, it is a collection of multiple protocols, so its multiple functions can effectively help us complete the management of the network.

We understand the SNMP implementation method. In order to provide a means to traverse the management information library, SNMP uses a tree naming method in its MIB to name each SNMP protocol management object instance. The name of each object instance is composed of an object class name and a suffix. The names of object classes are not repeated, so there is little danger of duplicate names between object instances of different object classes.

In the definition of a community, it is generally necessary to specify the scope of SNMP protocol management objects authorized by the community, and correspondingly specify which object instances are the "jurisdiction" of the Community. Accordingly, the definition of a community can be imagined as a multi-Cross Tree, providing a means to traverse all SNMP management object instances in alphabetical order. With this method, SNMP can use the get-next operator to sequentially locate the next object from an object.

The result returned by the get-next (object-instance) operation is an object instance identifier and its related information. The object instance is placed behind the specified identifier and bject-instance object in the preceding multi-tree. The advantage of this method is that, even if you do not know the specific name of the SNMP management object instance, the management system can find it one by one and extract its relevant information.

The process of traversing all SNMP management objects can start with the first object instance (this instance must be provided), and then use get-next, until an error (indicating that an SNMP management object instance does not exist) is returned (completing traversal ).

The SNMP protocol management agent determines whether the SNMP protocol management object access (operation) requested by other members of the community is allowed through the pre-defined access modes and permissions. The SNMP Protocol community concept is also applicable to the Proxy agent, except that the object contained in the conversion agent is mainly the content of other devices.

The SNMP application entity operates on the management objects in the Internet management information library. A subset of management objects that an SNMP application entity can operate on is called the snmp mib authorization range. The SNMP application entity still has further access control restrictions on access to management objects within the authorization scope, such as read-only and read/write.

Because the information is stored in the form of a table (a data structure), in the management concept of SNMP, all tables are considered as Subtrees, one of which is a table (and its name) is the root node of the corresponding subtree. Each column is the subnode under the root, and each row in a column is the subnode under the column node, and is the leaf node of the subtree.

Therefore, based on the previous sub-tree traversal idea, table traversal is to first access all elements in the first column, then access all elements in the second column ......, Until the last element. If you try to get the "Next" element of the last element, an error mark is returned.

The knowledge of SNMP management objects is explained here.