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  • About This Document

Loopback Detection

Loopback Detection (LBD) is a feature on the switch that provides protection against loops by transmitting loop protocol packets out of ports where loop protection has been enabled. When the switch sends out a loop protocol packet and then receives the same packet, it shuts down the port that received the packet. LBD operates independently of Spanning Tree Protocol (STP). After a loop is discovered, the port that received the loops is placed in the Shut Down state. A trap is sent and the event is logged.

To activate the Loopback Detection

1. Navigate to Policies > Policy Hierarchy > Switch Policy.
2. Select the System tab and scroll down to the Loopback Detection section.
3. Enable the toggle bar, Loopback Detection.