Layer-2 Trunk EtherChannel Carrying Multiple VLANs

Bundle lab · $29.99

Build a two-link LACP EtherChannel between SW1 and SW2 and convert the Port-channel into an 802.1Q trunk that explicitly carries VLANs 40 and 41. Validate end-to-end host reachability across VLAN 40 and confirm the trunk’s allowed VLAN list and switchport mode on the logical port-channel. Emphasis: deterministic EtherChannel configuration on member interfaces, correct trunking on the Port-channel, and verification with IOS show commands.

Learning objectives

• Create VLANs 40 and 41 on both switches and place access ports accordingly.
• Bundle Ethernet0/0 and Ethernet0/1 with LACP using channel-group 4 mode active on both SW1 and SW2.
• Configure Port-channel4 as an 802.1Q trunk and restrict its allowed VLANs to 40 and 41.
• Harden trunks by setting a non-default native VLAN and disabling DTP negotiation.
• Verify EtherChannel state and trunk operation with IOS show commands and confirm host reachability in VLAN 40.

Troubleshooting focus

• Detect and resolve VLAN allow-list drift on the trunk that prunes a required VLAN.
• Identify and correct native VLAN mismatches on trunks.
• Find and fix incorrect access VLAN assignments on host-facing ports.