3.3.12 Packet Tracer - Vlan Configuration.pka Today

He walked off. The switches hummed.

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

But when Alex tried to ping from PC1 (Accounting) to PC5 (Engineering)… 3.3.12 packet tracer - vlan configuration.pka

The Switch that Forgot How to Listen

On S1, G0/1:

“Wait,” Alex frowned. “That’s good. But why can’t PC1 ping PC3?”

Packet Tracer’s simulation mode revealed the truth: red packets dropping at the trunk port, rejected like a bouncer checking an expired ID. He walked off

“Right,” Alex groaned. “The switch doesn’t know which PC belongs to which VLAN. It’s like a hotel front desk that doesn’t ask for your room key.” Back on S1:

interface fastEthernet 0/1 switchport mode access switchport access vlan 10 exit interface fastEthernet 0/2 switchport mode access switchport access vlan 20 F0/3 → VLAN 30. F0/4 → VLAN 10. And so on. But when Alex tried to ping from PC1

“Walls built,” Alex said, leaning back. But Professor Lasky’s note glowed again: “VLANs are islands. How do islands talk?” Alex realized: S1 knows VLAN 10 exists on its own ports. S2 knows VLAN 10 exists on its own ports. But between switches? Silence.