CCNA Rapid-PVST+: Converge in Seconds, Not 50

Today's daily lab

Migrate a small campus from legacy PVST+ to Rapid-PVST+ across all switches, harden trunks, mark edge ports, and verify sub-second RSTP behaviours. A three-switch triangle with redundant trunks carries VLAN 10 to two hosts so you can validate end-to-end and observe convergence when a trunk flaps.

Learning objectives

• Convert PVST+ to Rapid-PVST+ consistently across all switches and verify mode agreement.
• Identify and correctly mark host-facing access ports as edge (PortFast) so RSTP skips listening/learning.
• Harden 802.1Q trunks with explicit encapsulation, native VLAN, and allow-lists while ensuring VLAN 10 traverses the triangle.
• Validate RSTP roles (Root/Designated/Alternate) and link types (P2p, Edge) and measure faster convergence by flapping a trunk.

Troubleshooting focus

• If any one switch remains in PVST+, neighbors fall back per-port and the campus does not operate in rapid-pvst mode. Check show spanning-tree summary on every switch.
• If a host port is not marked edge/PortFast, link-up incurs a delay and TCNs may ripple. Verify interface detail shows Edge: Yes or PortFast enabled.
• If VLAN 10 is not allowed across all trunks or native VLANs mismatch, hosts won’t ping. Compare trunk allow-lists and native VLANs on each side.
• If an access port is accidentally left as a trunk, hosts won’t join VLAN 10. Confirm access mode and access VLAN on the client-facing ports.