1、首先，在华为核心交换机开启DHCP服务（华为默认是没有开启DHCP服务的）
2、DHCP enable 开启DHCP服务
3、DHCP enable 开启DHCP服务
vlan 20
quit
int vlan k20
ip add 192.168.20.254 24
dhcp select global
ip pool vlan20
network 192.168.20.0 mask 24
gate-list 192.168.20.254
dns-list 202.96.128.166 114.114.114.114
lease day 1
excluded-ip-address 192.168.20.1 192.168.20.100