“Check,” Alex whispered, moving to S2 and S3. Repeat. Repeat. VLAN 10, 20, 30. Accounting. Engineering. Staff.

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

On S1, G0/1:

The scenario: VLAN Configuration . Objective: Slice this single broadcast domain into three separate pieces of virtual reality.

Alex cracked knuckles. Time to build walls. On Switch S1 , Alex typed:

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.