试用route-map一例

让除10.1.0.0/16 、内网之间、访问分校外必经10.1.0.6（PRoxy）

!

ip access-list extended Proxy
 deny   ip 10.1.0.0 0.0.255.255 any
 deny   ip 10.45.0.0 0.0.255.255 any
 deny   ip 10.0.0.0 0.255.255.255 10.0.0.0 0.255.255.255
 deny   ip 10.0.0.0 0.255.255.255 172.16.0.0 0.0.255.255
 permit ip 10.0.0.0 0.255.255.255 any

!

route-map Proxy permit 10
 match ip address Proxy
 set ip next-hop 10.1.0.6
!     
interface Vlan24
 description Lab Subnet
 ip address 10.14.0.1 255.255.0.0
 ip access-group 101 in
 ip helper-address 10.1.0.6
 no ip directed-broadcast
 ip pim sparse-mode
 ip policy route-map Proxy