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CCNA lab 5

Spanning tree: choose the root bridge per VLAN

Control which switch becomes the root bridge for each VLAN, move to Rapid PVST+, and protect the access ports with PortFast and BPDU Guard.

About 30 minutes 7 devices 5 tasksAdvanced

Scenario

SW1, SW2 and SW3 are cabled in a triangle with trunks, so spanning tree blocks one port per VLAN. With default priorities SW1 (an access switch with the lowest MAC address) wins the root election for every VLAN. Make SW2 the root for VLAN 10 and SW3 the root for VLAN 20, each switch the backup root for the other VLAN, run Rapid PVST+ everywhere, and make the PC ports edge ports that shut down if a switch is ever plugged into them.

Gi0/1Gi0/1Gi0/2Gi0/1Gi0/2Gi0/2Fa0/1eth0Fa0/2eth0Fa0/1eth0Fa0/2eth0SW2SW2 — Switch (Catalyst 2960-24)SW3SW3 — Switch (Catalyst 2960-24)SW1SW1 — Switch (Catalyst 2960-24)PC1PC1 — PCPC2PC2 — PCPC3PC3 — PCPC4PC4 — PC

Your tasks

  1. SW2 is the root bridge for VLAN 10, and PC1 still reaches PC3.
  2. SW3 is the root bridge for VLAN 20, and PC2 still reaches PC4.
  3. If a root fails, the other distribution switch takes over: SW3 is the VLAN 10 backup root and SW2 the VLAN 20 backup root.
  4. All three switches run Rapid PVST+.
  5. The four PC ports are PortFast edge ports with BPDU Guard.

The lab checks the result, not the exact commands. For example, a ping task passes only when the ping really succeeds through the network you built.

Start the lab