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What is SNMP


An SNMP-managed network consists of three key components:
  1)     Managed device
  2)     Agent — software which runs on managed devices
  3)     Network management station (NMS) — software which runs on the manager

The SNMP agent receives requests on UDP port 161. The manager may send requests from any available source port to port 161 in the agent. The agent response will be sent back to the source port on the manager. The manager receives notifications (Traps and InformRequests) on port 162. The agent may generate notifications from any available port. When used with Transport Layer Security or Datagram Transport Layer Security requests are received on port 10161 and traps are sent to port 10162.

•       UDP port 161 used for polling
•       UDP port 162 used for receiving trap/notifications from managed devices.
•        Every device that implements SNMP must use these port numbers as the defaults, but some vendors allow you to change the default ports in the agent’s configuration.

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