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Any configuration changes made locally on the switch won't be synchronized with Sophos Central. We recommend making changes from the Sophos Central control panel instead.

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Loopback detection (LBD)

Loopback detection (LBD) protects against loops by sending loop protocol packets out of ports with loop protection turned on. When Sophos Switch sends a loop protocol packet and subsequently receives the same packet, the port that received the packet is shut down, and a trap message is sent.

LBD operates independently of the Spanning Tree Protocol (STP), which means you can use LBD with devices that don't support STP or when STP isn't used in the wider network.

Global settings

To turn Loopback detection status on or off, select Turned on or Turned off.

Port status

The Port status shows whether ports are blocked by the LBD function.