在三层交换机上创建三个VLAN，其中2个VLAN的ID需与二层交换机相同。将与二层交换机的两个接口设置为trunk模式，另外一个接口设置为access模式并配置归属为第三个VLAN。最后配置这三个VLAN的 IP地址。配置命令填入表中

| 配置命令 |
| ---------------------------------------- |
| vlan 10 |
| vlan 20 |
| vlan 30 |
| interface GigabitEthernet0/1 |
| switchport mode trunk |
| switchport trunk allowed vlan 10,20 |
| interface GigabitEthernet0/2 |
| switchport mode trunk |
| switchport trunk allowed vlan 10,20 |
| interface GigabitEthernet0/3 |
| switchport mode access |
| switchport access vlan 30 |
| interface vlan 10 |
| ip address 192.168.10.1 255.255.255.0 |
| interface vlan 20 |
| ip address 192.168.20.1 255.255.255.0 |
| interface vlan 30 |
| ip address 192.168.30.1 255.255.255.0 |