CCNA Day 2: VLANs and Port Security

Archive lab

Configure a compact branch LAN with router-on-a-stick inter-VLAN routing, two access switches, and two user VLANs. Implement VLANs, 802.1Q trunks with a hardened native VLAN, secure user-facing ports with port-security, and verify end-to-end reachability from the hosts. Includes realistic troubleshooting of VLAN assignment, trunk allow-lists, and port-security violations.

Learning objectives

• Create and name VLANs and map them to IP subnets in a branch LAN
• Configure access and trunk ports, including native VLAN hardening and allowed VLAN lists
• Implement sticky MAC port-security on user-facing access ports with proper violation handling
• Verify and troubleshoot VLAN, trunk, and port-security issues from end hosts

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.