STP Anomaly Detection

The STP Anomaly Detection offers proactive insights by recognizing any STP anomalies in the customer's network and recommending best practices for addressing them.

The following are some of the best practices:

  • If a core or aggregator device is present, an access device should not be configured as the STP root bridge.

  • Any ports that point to clients or access points should not be configured as root ports.

  • Aggregator and core devices should have a higher STP priority than access devices.

  • Highlight any significant Topology Change Notification (TCN) count variations that indicate an unstable network.

To access the insight, complete the following steps:

  1. Access the Insights page. For more information, see Accessing Insights Page.

  2. Click the STP Anomaly Recommender tab.

By default, the 24 hours view is displayed. You can view the following metrics:

  • Actions—Click the View Topology button to view the topology of the site.

  • High Topology Change Notification counts detected—Highlights elevated topology change notifications (TCNs), indicating frequent STP reconvergence. Click View Actions to open a detailed analysis and remediation view for the detected anomaly:

    Figure 1: STP Anomaly - Actions Card

    • Topology Change Count (Top 5 Impacted Devices)—Displays a time-series graph of topology-change counts for the top five impacted devices that have experienced more than 200 topology changes. Use this graph to correlate instability with specific time periods. Hover over the graph to view the exact values.

    • Investigate Uplink Flaps—Identifies uplink interfaces experiencing frequent link flaps. Uplink flaps in the STP topology causes port state to change and contribute to TCN spikes.

    • Investigate Device Reboots (Fix)—Highlights devices that rebooted during the analysis window. Device reboots can trigger STP reconvergence and contribute to topology instability.

    • Set / Stabilize Root Bridge—Recommends anchoring the STP root bridge on a core or aggregation device to prevent frequent root bridge changes. Instability in the topology can often be identified by frequent root bridge changes when the correct priority is not set.

  • Actions – Configure STP Root Bridge on Core/Aggregator Device—The system identifies the current and recommended STP root bridge along with its device serial and model.

  • Actions – Configure Recommended Priority for Core/Aggregate Devices as per best practices—The system suggests optimal STP priority values. You can view the Device Name, Device Serial, Model, IP Address, Current Priority, Recommended Priority. A warning message indicates that changing the switch priority will cause spanning-tree reconvergence and may briefly impact network traffic.