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Switching and VLANs

Trunks, access ports, inter-VLAN routing, spanning tree, and link bundling, the layer-2 core.

5 challenges · ~3 h · every step earns its own verified proof

0/5 solved
Start: VLAN 10 and VLAN 20 can't talk →
  1. VLAN 10 and VLAN 20 can't talkmedium~45 min

    Router-on-a-stick. See how the trunk's tags and the router subinterfaces have to line up.

  2. A native VLAN mismatch on the trunkmedium~35 min

    A native VLAN mismatch bridges the wrong traffic. Align both ends of the trunk.

  3. VLAN 20 can't reach VLAN 10medium~45 min

    Move inter-VLAN routing onto the switch itself, an SVI per VLAN.

  4. The wrong switch is the spanning-tree rootmedium~40 min

    Decide the spanning-tree root on purpose instead of letting MAC addresses pick it.

  5. The link bundle won't come upmedium~40 min

    Bond two links into one with LACP, and learn why both ends have to agree.