After a VLAN is configured, VLAN configurations can be validated using Cisco IOS show commands.

Figure 1 displays the show vlan and show interfaces command options.

In the example in Figure 2, the show vlan name student command produces output that is not easily interpreted. The preferable option is to use the show vlan brief command. The show vlan summary command displays the count of all configured VLANs. The output in Figure 2 shows seven VLANs.

The show interfaces vlan vlan-id command displays details that are beyond the scope of this course. The important information appears on the second line in Figure 3, indicating that VLAN 20 is up.

Use the Syntax Checker in Figure 4 to display the VLAN and switch port information, and verify VLAN assignments and mode.