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Troubleshooting › SNMP Queries Using Investigations › Situation 1-- Server Incident › Analyze the SNMP Performance Data › Analyze the SNMP Trace Route Data

Analyze the SNMP Trace Route Data

The report presents a route with multiple hops. For detailed analysis, select the performance statistics for the hop with the largest delay. Click the Report icon in the far right column. The SNMP performance report for the router opens in a new window. For network incidents, follow the checklist for determining the root cause of a network issue.

  1. Check the CPU and Memory utilization of the device. If the either the memory or CPU usage is high, the router is being overloaded by a large configuration or burdened with excessive packet processing. Oftentimes CPU usage can rise if of a virus outbreak or DDOS attack on the device when it is being flooded with erroneous packets.

    Follow the troubleshooting process for the type of device to reduce CPU or memory utilization to return performance levels to normal.

  2. Ensure that all interfaces are listed correctly and the status is Up. If the interface in question has failed over to a secondary interface, ensure that the speeds are the same. If the secondary interface has a lower speed, network latency can increase until the primary interface is returned to functioning properly.
  3. Verify that the interface is not seeing any discards or errors. If the discards or errors are being reported, log into the router and troubleshoot the interface connectivity for issues relating to the media type of the interface. Discards and errors tend to indicate a problem with the connectivity between that interface and the connecting router or device.
  4. Ensure that the interface utilization is not exceeding capacity. The interface ingress bits per second must be less than the circuit rating. If the utilization of the circuit is a problem, look into the traffic flows on the interface to identify what is causing the sudden congestion.
  5. If the device is operating as expected, then check the remaining hops investigated via SNMP following the same workflow to identify and resolve any potential issues with the network latency between the end-user and the servers affected by the network incident.