D-Link DES-3326S manual Minimize the number of ports in the blocking state

DES-3326S Layer 3 Fast Ethernet Switch User’s Guide

Organize the redundant links and tune the port cost parameter of STP to force those ports to be in the blocking state.

For each VLAN, know which ports should be blocking in a stable network. A network diagram that shows each physical loop in the network and which ports break which loops is extremely helpful.

Minimize the number of ports in the blocking state.

A single blocking port transitioning to the forwarding state at an inappropriate time can cause a large part of a network to fail. Limiting the number of blocked ports help to limit the risk of an inappropriate transition.

336Understanding and Troubleshooting the Spanning Tree Protocol