---

R1

enable
configure terminal
hostname R1
no ip domain-lookup
interface g0/0
 description LAN_to_S1
 ip address 192.168.10.1 255.255.255.0
 ip helper-address 10.1.1.2
 no shutdown
exit
interface s0/0/0
 description WAN_to_R2
 ip address 10.1.1.1 255.255.255.252
 no shutdown
exit
ip route 192.168.20.0 255.255.255.0 10.1.1.2
ip route 192.168.30.0 255.255.255.0 10.1.1.2
ip route 10.2.2.0 255.255.255.252 10.1.1.2
end
write



R2


enable
configure terminal
hostname R2
no ip domain-lookup
ip dhcp excluded-address 192.168.10.1 192.168.10.10
ip dhcp excluded-address 192.168.30.1 192.168.30.10
ip dhcp pool R1-LAN
 network 192.168.10.0 255.255.255.0
 default-router 192.168.10.1
 dns-server 192.168.20.254
exit
ip dhcp pool R3-LAN
 network 192.168.30.0 255.255.255.0
 default-router 192.168.30.1
 dns-server 192.168.20.254
exit
interface g0/0
 description LAN_to_S2
 ip address 192.168.20.1 255.255.255.0
 no shutdown
exit
interface s0/0/0
 description WAN_to_R1
 ip address 10.1.1.2 255.255.255.252
 clock rate 128000
 no shutdown
exit
interface s0/0/1
 description WAN_to_R3
 ip address 10.2.2.2 255.255.255.252
 clock rate 128000
 no shutdown
exit
interface g0/1
 description WAN_to_ISP
 ip address dhcp
 no shutdown
exit
ip route 192.168.10.0 255.255.255.0 10.1.1.1
ip route 192.168.30.0 255.255.255.0 10.2.2.1
end
write



R3


enable
configure terminal
hostname R3
no ip domain-lookup
interface g0/0
 description LAN_to_S3
 ip address 192.168.30.1 255.255.255.0
 ip helper-address 10.2.2.2
 no shutdown
exit
interface s0/0/1
 description WAN_to_R2
 ip address 10.2.2.1 255.255.255.252
 no shutdown
exit
ip route 192.168.20.0 255.255.255.0 10.2.2.2
ip route 192.168.10.0 255.255.255.0 10.2.2.2
ip route 10.1.1.0 255.255.255.252 10.2.2.2
end
write