Deleting a VLAN on a Cisco switch is a one-line command — but it has ripple effects that are easy to miss if you don’t understand what happens to the ports that were using it. This guide covers the straightforward case of removing a single VLAN, the more surgical approach of pulling a VLAN off... » read more
Every 802.1Q trunk link has exactly one VLAN that behaves differently from all the others — the native VLAN, whose traffic travels untagged. Left at its default setting, it’s also one of the more commonly overlooked security gaps in a switched network, and one of the most common causes of a trunk that looks “up”... » read more
Getting a VLAN running on a Cisco switch is usually the easy part — assigning a port, creating the VLAN, and confirming connectivity takes just a few commands. The harder parts show up later: understanding why VLAN IDs above 1005 behave differently, and diagnosing exactly why a device suddenly can’t ping across a VLAN it... » read more
Whether you’re segmenting a small office network or managing dozens of switches across an enterprise campus, VLAN configuration follows the same core logic everywhere — even though the exact commands and menus differ from vendor to vendor. This guide starts with the fundamental concepts, walks through a full Cisco CLI configuration step by step, compares... » read more