CCNA Port Security 5: Violation Shutdown & Manual Recovery

Bundle lab · $29.99

Hands-on CCNA L2 switching lab: build a small campus with a distribution switch and two access switches carrying a shared user VLAN over 802.1Q trunks. Harden access ports with sticky port-security in violation shutdown mode. Intentionally seed and diagnose broken trunks/host VLANs, restore end-to-end host reachability, then trigger a port-security violation to observe err-disabled behavior and perform manual recovery.

Learning objectives

• Create a user VLAN and place host-facing ports in that access VLAN on L2 access switches
• Build 802.1Q trunks between access and distribution switches, with a hardened native VLAN and allowed list
• Enable switchport port-security on user access ports, using sticky MAC and violation mode shutdown
• Trigger a port-security violation and identify the err-disabled state and counters
• Manually recover an interface from err-disabled using shutdown/no shutdown and re-verify host connectivity

Troubleshooting focus

• Verify every link's interface status and IP addressing (`show ip interface brief`) and correct any interface that is down or misaddressed.
• Confirm each device's running configuration matches the lab objective, and bring any interface, route, or service that is not in its expected state back to health.
• Trace end-to-end reachability with ping/traceroute and isolate the first hop where forwarding fails.