Overview

By identifying where issues can occur in a Spanning Tree environment, and defining why these issues occur can make it easier to isolate the problems when they occur. Enhancements have been made to the STP protocol to help reduce the likelihood of anomalous STP conditions if they are implemented. Forwarding Loops and Black Holes are conditions that can result from improper Spanning Tree operation. These conditions can be detected and prevented through the execution of specific troubleshooting and configuration commands. Two major enhancements have been made to original 802.1D specifications for Spanning Tree. Rapid Spanning Tree, 802.1w, provides a faster and more resilient means of adapting to topology change in a switched environment. Multiple Spanning Tree provides an alternative to Per VLAN and Common Spanning Tree by requiring only a minimal number of STP instances in a switched environment.