拓扑图如下：
SW-1配置命令如下:
基础配置为进系统视图，修改主机名.
<Huawei>system-view //进系统视图
Enter system view, return user view with Ctrl+Z.
[Huawei]sysname SW-1 //修改主机名为SW-1
创建vlan，配置工作模式，将接口加入到vlan配置
[SW-1]vlan batch 10 20 30 //创建vlan 10 20 30
[SW-1]int g0/0/1 //进g0/0/1接口
[SW-1-GigabitEthernet0/0/1]port link-type access //配置工作模式为access
[SW-1-GigabitEthernet0/0/1]port default vlan 10 //将g0/0/1接口加入到vlan10
[SW-1-GigabitEthernet0/0/1]int g0/0/2 //切换接口
[SW-1-GigabitEthernet0/0/2]port link-type access //配置工作模式为access
[SW-1-GigabitEthernet0/0/2]port default vlan 20 //将g0/0/2接口加入到vlan20
[SW-1-GigabitEthernet0/0/2]int g0/0/3 //切换接口
[SW-1-GigabitEthernet0/0/3]port link-type access //配置工作模式为access
[SW-1-GigabitEthernet0/0/3]port default vlan 30 //将g0/0/3接口加入到vlan30
[SW-1-GigabitEthernet0/0/3]q //退到上一层
进入虚接口，配置IP地址和子网掩码
[SW-1]int Vlanif 10 //进入vlanif 10 接口
[SW-1-Vlanif10]ip address 192.168.10.254 24 //配置IP地址和子网掩码
[SW-1-Vlanif10]int vlanif 20 //切换接口
[SW-1-Vlanif20]ip address 192.168.20.254 24 //配置IP地址和子网掩码
[SW-1-Vlanif20]int vlanif 30 //切换接口
[SW-1-Vlanif30]ip address 192.168.30.254 24 //配置IP地址和子网掩码