Chapter 25 Access Control
Figure 94 Console Port Priority“Local administrator is configuring this device now!!! Connection to host lost.”
25.3 About SNMP
Simple Network Management Protocol is a protocol used for exchanging management information between network switches. SNMP is a member of TCP/IP protocol suite. A manager station can manage and monitor the switch through the network via SNMP version one (SNMPv1) and/or SNMP version 2c. The next figure illustrates an SNMP management operation. SNMP is only available if TCP/IP is configured.
Figure 95 SNMP Management Model
An SNMP managed network consists of two main components: agents and a manager.
An agent is a management software module that resides in a managed switch (the GS). An agent translates the local management information from the managed switch into a form compatible with SNMP. The manager is the console through which network administrators perform network management functions. It executes applications that control and monitor managed devices.
The managed devices contain object variables/managed objects that define each piece of information to be collected about a switch. Examples of variables include such as number of packets received, node port status etc. A Management Information Base (MIB) is a collection of managed objects. SNMP allows a manager and agents to communicate for the purpose of accessing these objects.
SNMP itself is a simple request/response protocol based on the manager/agent model. The manager issues a request and the agent returns responses using the following protocol operations:
Table 63 SNMP Commands
COMMAND | DESCRIPTION |
Get | Allows the manager to retrieve an object variable from the agent. |
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GetNext | Allows the manager to retrieve the next object variable from a table or list within |
| an agent. In SNMPv1, when a manager wants to retrieve all elements of a table |
| from an agent, it initiates a Get operation, followed by a series of GetNext |
| operations. |
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