3.3.12 Packet Tracer - Vlan Configuration.pka Apr 2026

The problem slapped Alex in the face: .

Alex smiled at the virtual topology—three separate networks living on the same wires, never arguing, never colliding.

interface gigabitEthernet 0/1 switchport mode trunk switchport trunk allowed vlan 10,20,30 Same on S2’s G0/1 and S3’s G0/2. 3.3.12 packet tracer - vlan configuration.pka

The basement lab of Meridian Community College. Racks of aging but reliable Cisco switches hum in the corner. On a monitor, the Packet Tracer interface glows green.

“This is too friendly,” Alex muttered. “I don’t want Accounting to talk to Engineering. They have nothing in common except coffee.” The problem slapped Alex in the face:

Professor Lasky’s note floated at the top of the instructions: “VLANs don’t just happen. You build walls where there are none.”

“Perfect isolation,” Alex said, closing Packet Tracer. “Almost as good as my weekend plans.” The basement lab of Meridian Community College

But when Alex tried to ping from PC1 (Accounting) to PC5 (Engineering)…

The default port between S1 and S2 (Gig0/1) was just a regular port. It saw a ping from PC1 (VLAN 10, S1) and dropped it before it reached S2.

He walked off. The switches hummed.

The Switch that Forgot How to Listen