Copyright (c) 2026 MindMesh Academy. All rights reserved. This content is proprietary and may not be reproduced or distributed without permission.

6.3.1. Switching and Routing Problems

STP Issues:
  • Broadcast storm: STP not working, loops present—network overwhelmed
  • Root bridge selection: Wrong switch is root, traffic takes suboptimal paths
  • Port in wrong state: Stuck blocking, not transitioning to forwarding
VLAN Issues:
  • Wrong VLAN assignment: Device in wrong VLAN, can't reach intended resources
  • Trunk misconfiguration: VLANs not allowed on trunk, or native VLAN mismatch
Routing Issues:
  • Missing route: No path to destination in routing table
  • Wrong next-hop: Packets sent to wrong router
  • AD/metric issues: Suboptimal path selected
Alvin Varughese
Written byAlvin Varughese
Founder•15 professional certifications