Читать книгу CCNP Enterprise Certification Study Guide: Implementing and Operating Cisco Enterprise Network Core Technologies - Ben Piper, David Higby Clinton - Страница 83

Loop Guard is a Spanning Tree extension that places a Spanning Tree port into a loop-inconsistent state if it fails to receive BPDUs for a VLAN. Unlike UDLD aggressive mode, which disables an interface, Loop Guard blocks ports on a per-VLAN basis. You can enable Loop Guard using the interface command spanning-tree guard loop.