Design Principles of the Linux SNMP protocol

Generally, we use the SNMP protocol, most of which is performed in Windows. However, Linux SNMP is widely used. Now let's take a look at the content related to Linux SNMP. See how the specific design is implemented. In fact, Linux SNMP is designed to be protocol-independent, so it can be used on IP addresses, IPX, AppleTalk, OSI, and other transport protocols.

Linux SNMP is a series of protocol groups and specifications that provide a method to collect Network Management Information from devices on the network. Linux SNMP also provides a way for devices to report problems and errors to network management workstations.

MIB: Management Information Library

SMI: Structure and identifier of Management Information

Linux SNMP Algorithm

There are two methods to collect data from managed devices: one is to only polling-only), and the other is to interrupt-based.

If you only use the round-robin method, the network management workstation is always under control. The defect of this method lies in the real-time information, especially the real-time error. How often do you perform round robin on devices?

If the polling interval is too small, too much unnecessary traffic will be generated. If the polling interval is too large and the order is incorrect during the polling, the notifications about some major catastrophic events will be too delayed. This violates the proactive network management of Linux SNMP.

When an exception occurs, you can immediately notify the network management workstation of the interruption-based method. Assume that the device has not crashed, and there is still an available communication channel between the managed device and the management workstation ).

However, this method is not without its defects. First, system resources are required to generate errors or self-traps. If you have to forward a large amount of information, the managed device may have to consume more time and system resources to generate self-traps, this affects the implementation of its main functions against the principles of Network Management 2 ).

Moreover, if several self-traps of the same type occur in succession, a large amount of network bandwidth may be occupied by the same information, which violates the principle of network management 1 ). This is especially bad if we are stuck with network congestion issues.

One way to overcome this defect is to set a threshold value threshold for the managed device ). However, unfortunately, this method may once again violate principle 2 of network management, because the device must consume more time and system resources to determine whether a trap should be generated.

As a result, the combination of the above two methods: trap-ccted polling for the Self-trapped polling method) may be the most effective method for implementing network management in Linux SNMP. Generally, the network management workstation polls the agent in the managed device to collect data, and displays the data in the console in a digital or graphical representation. This allows the network administrator to analyze and manage devices and network traffic.

The agent in the managed device can report errors to the network management workstation at any time, such as pre-defined threshold out-of-bounds. The agent does not need to wait until the management workstation polls the agent to receive these errors. These errors are known as Linux SNMP traps ).