Cisco Sx350 Cli Manual page 1139

Spanning-Tree Commands
Cisco Sx350 Ph. 2.2.5 Devices - Command Line Interface Reference Guide
Syntax
spanning-tree loopback-guard
no spanning-tree loopback-guard
Parameters
N/A
Default Configuration
N/A
Command Mode
Global
User Guidelines
This enables shutting down all interfaces if a loopback BPDU is received on it.
Example
switchxxxxxx(config)# spanning-tree loopback-guard
58
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