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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

LED is off

The Sensor is turned off.

Restore Sensor power.

The Sensor port cable is disconnected.

Check the Sensor cable connections.

Sensor is operational but not monitoring traffic

Network device cables have been disconnected.

Check the cables and make sure they are properly connected to both the network devices and the bypass switch.

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 bypass switch.

Runts or giants errors on switch and routers

Improper cabling or port configuration

Make sure that the transmitting and receiving cables are properly connected to the bypass switch.

The critical fault, Switch absent appears in the Manager System faults page.

The fail-open kit is disconnected.

Check the fail-open kit and make sure it is properly connected to the Sensor.

For more information on troubleshooting steps and faults generated in the Manager, see the Troubleshooting section in Trellix Intrusion Prevention System Product Guide.