Simple Network Management Protocol (SNMP) consists of a set of network management standards, including an application layer protocol, a database schema, and a set of resource objects. This protocol enables network management systems to monitor devices connected to the network for any management concerns. This protocol is part of the internet protocol suite defined by the Internet Engineering Task Force (IETF). The goal of SNMP is to manage the software and hardware platforms produced by many manufacturers on the Internet, so SNMP is also greatly influenced by the Internet standard network management framework. SNMP has come out to the third version of the protocol, and its functions have been greatly enhanced and improved.
1. What is SNMP?
SNMP is the abbreviation of "Simple Network Management Protocol", which means Simple Network Management Protocol in Chinese. It is an application layer protocol defined by the Internet Working Group in RFC1157 for exchanging management or monitoring information between network entities or nodes.
Second, why do you need SNMP?
As operation and maintenance personnel, a large part of our work is to ensure that our network can operate normally and stably. Therefore, monitoring, controlling, and managing various network devices has become our daily work. In the early days of the rise of the network, the maintenance method was that the operation and maintenance personnel squatted at the near end to perform various operations on the equipment. Such near-end maintenance is also nearly impossible. Therefore, the need for remote management of the network is increasingly urgent, and SNMP emerges as the times require. Using SNMP, a workstation running network management software can monitor and collect information from thousands of network devices, which can be used to construct a network or locate problems in the network.
Third, the advantages of SNMP
As the name suggests, this protocol is simple to understand and has little overhead to deploy. Because it is simple enough, it is widely accepted, in fact it has become the main network management standard. Implementing SNMP management on a network device is simpler and more straightforward than most other management methods.
Using SNMP will bring the following benefits:
Standardized protocol: SNMP is a standard network management protocol for TCP/IP networks. Internet standard protocols are open, non-proprietary voluntary contributions by Internet organizations, and SNMP maintenance and all future enhancements will be based on existing protocol standards.
Widely recognized: All major vendors support SNMP. All SNMP managed devices use the same management interface to support a common set of management messages.
Portability : SNMP is independent of operating system and programming language. The functional design of SNMP is also portable. At the same time, it defines a set of core operations, which all devices supporting SNMP need to support this set of operations.
Lightweight: SNMP enhances device management capabilities without impacting device operation or performance. Network devices can add SNMP management support at the expense of minimal resource consumption and a slight load.
Scalability: The same set of core operations is supported on all SNMP-managed devices. SNMP also supports the interaction of various types of device information in computer network devices, and it becomes easier for devices to join the network.
Widespread deployment : SNMP is the most popular management protocol, most concerned by equipment vendors, and is widely deployed on a wide variety of devices.
working principle
In typical SNMP usage, many systems are managed, and one or more systems manage them. A software element called an agent runs on each managed system and reports information to the management system via SNMP.
Basically, SNMP agents present management data in variables. The management system retrieves information through GET, GETNEXT and GETBULK protocol commands, or the agent uses TRAP or INFORM to transmit data without being asked. The management system can also send a request for configuration update or control to achieve the purpose of actively managing the system through the SET protocol command. Configuration and control commands are only used when the network infrastructure needs to change, while monitoring commands are usually the norm.
Variables accessible through SNMP are combined in a hierarchical fashion. These hierarchies and other metadata (such as variable types and descriptions) are described in management information bases (MIBs).
SNMP is a network management standard based on the TCP/IP protocol suite, and is a standard protocol for managing network nodes (such as servers, workstations, routers, switches, etc.) in an IP network. SNMP enables network administrators to improve network management efficiency, find and solve network problems in a timely manner, and plan network growth. Network administrators can also receive notification messages from network nodes and alarm event reports through SNMP to learn about network problems.
The network managed by SNMP mainly consists of three parts:
managed device
SNMP agent
Network Management System (NMS)