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Troubleshooting the Sensor

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This section lists some common installation problems, the possible causes, and the corresponding solutions.

Problem

Possible Cause

Solution

LEDs are off.

The Sensor is turned off.

Restore Sensor power.

Link LEDs are off.

The Sensor port cable is disconnected, or not seated properly.

Check the cables between the network devices and the Sensor monitoring ports

Sensor is operational but the monitoring ports are not up.

Network device cables have been disconnected.

Check the cables and make sure they are properly connected to the network devices or Active Fail-Open kits.

Sensor is operational and the cables are properly connected but it is not monitoring the traffic.

The Sensor ports have not been enabled in the Manager.

The Sensor will not monitor traffic on the ports unless the ports are enabled in the Manager. Ports are disabled in case of Sensor failure; you must re-enable them for Sensor monitoring to resume.

Network or link problems

Improper cabling or port configuration

Make sure that the transmitting and receiving cables are properly connected to the network devices or Active Fail-Open kits.

Runts or giants errors on switch and routers

Improper cabling or port configuration, or malfunctioning cables

Make sure that the transmitting and receiving cables are properly connected to the network devices or Active Fail-Open kits. Check that the port configurations are matching on both ends or replace the network cables.

The system fault "Switch absent" appears on Faults tab in the Logs page.

The Active Fail-Open Kit is disconnected.

Check the Active Fail-Open Kit and make sure it is properly connected to the Sensor.

You can monitor whether the health status of the Sensor(s) is in the GUID-C395F07B-D0CD-480A-BCC2-FB886010F5DD-low.pngGood state from the Devices → <Admin Domain Name> → Global → Sensor Health → Health Status page. If you encounter any faults, Trellix recommends to take the required actions. For more information on how to check the health status of a Sensor and take actions as per requirement, refer to the section Monitoring Sensor Health in Trellix Intrusion Prevention System Product Guide. For more information on the generated faults, refer to the section Sensor Faults in Trellix Intrusion Prevention System Product Guide.

Note

If any issue still persist or you encounter problems in troubleshooting them, contact Trellix Support for further assistance.