How do I troubleshoot VLAN misconfigurations?
VLAN misconfigurations break connectivity in predictable ways. Start with the symptoms, then work through the layers: switch ports, trunk links, routing, spanning tree, and end devices. 1. Identify the Symptoms Devices in the same VLAN can’t talk to each other. Devices can’t reach other VLANs (inter-VLAN routing failure). Specific users or services report connectivity loss. […]