CCNA 200-301 Portable Command Guide, 5th Edition

Chapter 11. Spanning Tree Protocol

This chapter provides information and commands concerning the following topics:

• Spanning Tree Protocol definition

• Enabling Spanning Tree Protocol

• Changing the spanning-tree mode

• Configuring the root switch

• Configuring a secondary root switch

• Configuring port priority

• Configuring the path cost

• Configuring the switch priority of a VLAN

• Configuring STP timers

• Configuring optional spanning-tree features

  • PortFast

  • BPDU Guard (2xxx/3xxx series)

  • BPDU Guard (9xxx series)

• Enabling the extended system ID

• Verifying STP

• Troubleshooting Spanning Tree Protocol

• Configuration example: PVST+

Spanning Tree Protocol Definition

The spanning tree standards offer the same safety that routing protocols provide in Layer 3 forwarding ...