VLAN

Virtual LANs and Layer 2 switching, the foundation of every campus network. Articles tagged VLAN cover fundamentals, trunking, inter-VLAN routing, EtherChannel, troubleshooting, and campus design on Cisco Catalyst switches.

29 posts

VLAN

Mastering ‘Show Interface Status’ in Cisco: Top 5 Essential Tips

show interface status tells you more than up/down. Here are five tips for reading it quickly: port status, VLAN, speed/duplex, errdisable, and description use.

Dec 23, 2024 4 min read

VLAN

EtherChannel Fundamentals: Link Aggregation, PAgP vs LACP, and Load Balancing

EtherChannel presents multiple physical links as a single logical interface to the spanning tree algorithm, eliminating blocked ports and enabling true line-rate redundancy.

Dec 23, 2024 7 min read

VLAN

VLAN Naming, Ranges, and Management Best Practices on Cisco IOS XE

Deep dive into VLAN naming conventions, the difference between standard and extended range VLANs, and best practices for VLAN management and deletion on Cisco Catalyst switches.

Dec 23, 2024 6 min read

VLAN

Troubleshooting SVI Up/Down Issues on Cisco Catalyst Switches

An SVI stuck in up/down means something is wrong with the underlying VLAN — no active ports, a deleted VLAN, or STP blocking every path. Here is how to diagnose and fix every cause.

Dec 23, 2024 6 min read

VLAN

VLAN Trunking Explained: 802.1Q, Allowed Lists, and Trunk Negotiation

Learn why VLAN trunks exist, how 802.1Q tagging works, the difference between ISL and 802.1Q, and how allowed VLAN lists and trunk negotiation function in Cisco networks.

Dec 21, 2024 7 min read