Free CCNA | Configuring STP (PVST+) | Day 21 Lab | CCNA 200-301 Complete Course

Introduction

In this tutorial, we will cover how to configure Spanning Tree Protocol (STP) using Per VLAN Spanning Tree (PVST+) as part of the CCNA 200-301 curriculum. By following these steps, you will gain hands-on experience with STP, understand its importance in preventing loops in network topologies, and learn how to analyze STP using the Command Line Interface (CLI).

Step 1: Understand STP Basics

• Familiarize yourself with the purpose of STP:
  • Prevents broadcast storms by eliminating loops in switched networks.
  • Works by designating a root bridge and blocking redundant paths.
• Know the key STP terms:
  • Root Bridge: The central switch in the topology.
  • Bridge ID: Unique identifier for each switch, based on priority and MAC address.
  • Port States: The operational status of ports (Blocking, Listening, Learning, Forwarding).

Step 2: Calculate STP Topology

• Identify the switches in your network and determine their Bridge IDs.
• Use the following process to select the root bridge:
  • Compare the Bridge IDs of all switches.
  • The switch with the lowest Bridge ID becomes the root bridge.
• Document the role of each switch in the topology based on STP calculations.

Step 3: Configure STP on Switches

• Access the CLI of each switch using a console connection or SSH.
• Enter global configuration mode:

  configure terminal
  

• Set the priority to influence the root bridge election:

  spanning-tree vlan [vlan-id] priority [priority-value]
  

  • Example for VLAN 1:

  spanning-tree vlan 1 priority 4096
  

Step 4: Verify STP Configuration

• Use the following commands to check STP status:
  • To view the STP status on a switch:

  show spanning-tree
  

  • This command displays information about the root bridge and port states.
• Look for the designated root bridge and ensure that the correct ports are in forwarding or blocking states.

Step 5: Analyze STP with CLI

• Use additional commands to get detailed STP information:
  • To view specific VLAN STP information:

  show spanning-tree vlan [vlan-id]
  

  • Analyze port roles and states for troubleshooting.
• Check for any potential issues or misconfigurations that could lead to loops or inefficient traffic flows.

Conclusion

In this tutorial, you learned how to configure and analyze Spanning Tree Protocol (PVST+) in a network environment. By calculating the STP topology, configuring switches, and verifying their status through CLI commands, you have gained practical skills that are essential for managing network stability. As a next step, consider practicing these configurations in a lab environment using simulation tools like Cisco Packet Tracer or Boson NetSim to reinforce your understanding.