Cisco端配置：（仅仅DHCP）
service dhcp
ip dhcp relay information trust-all
interface Vlan4
ip address 192.168.4.254 255.255.255.0
ip helper-address 10.0.0.11
!
interface Vlan6
ip address 192.168.6.254 255.255.255.0
ip helper-address 10.0.0.11
!
2、DHCP的常用配置：
ip dhcp excluded-address 192.168.10.1 192.168.10.20
ip dhcp excluded-address 192.168.10.240 192.168.10.254
ip dhcp excluded-address 192.168.20.1 192.168.20.20
ip dhcp excluded-address 192.168.20.240 192.168.20.254
ip dhcp pool 192.168.10.0/24
network 192.168.10.0 255.255.255.0
default-router 192.168.10.254
dns-server 10.0.0.3 202.96.134.133
!
ip dhcp pool 192.168.20.0/24
network 192.168.20.0 255.255.255.0
default-router 192.168.20.254
dns-server 10.0.0.3 202.96.134.133
ip dhcp pool foriosDEV1
host 192.168.7.28 255.255.255.0
client-identifier 0168.5b35.9d90.ea
!
ip dhcp pool foriosDEV2
host 192.168.7.22 255.255.255.0
client-identifier 0110.ddb1.d7e2.f6