An AR3260 router in an office in country N is impacted by SNMP packets, causing a high CPU usage on the main control plane

Root analysis: The SNMP process is overloaded.
Troubleshooting procedure:
1. The NMS fails to manage the AR, therefore corresponding link may not be reached. Perform a ping test, and find that the link is reachable.
2. Check the CPU usage of the AR router, and find that the SNMP process is overloaded (peak: 56.2%). Run the display snmp-agent statistics command, and find a great number of SNMP query packets (shown as below). The fault may be caused by the excessive SNMP query packets received from the intranet NMS. Measure traffic on the Ethernet aggregation link that connects to the intranet server, and find that a great number of SNMP packets are not received from the intranet.
3. Run the debug snmp-agent packet command and find that the packets are sent from a public network address (shown as below). Measure traffic on the WAN interface to confirm the finding. Apply a streaming policy to the WAN interface to filter the SNMP packets. The CPU usage on the main control plane drops back to normal.
For details, see the URL: CPU Usage of the Main Control Plane on the AR3260 Is High Because of Many SNMP Packets.

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