Summary:

 

1.  Configure a static, default route on R1 pointing to the ISP.

2. Configure a static default route on R2 pointing to R1

3. Configure a static default route on R3 pointing to R2.

4. Option: using RIP for R2 and R3 rather than the static default routes.

 

 

 

1.  Configure a static, default route on R1 pointing to the ISP.

R1.
ip route 0.0.0.0 0.0.0.0 192.168.1.100


#Test: add a couple of loopback IPs on ISP so we can test

int l0
 ip address 4.2.2.2 255.255.255.255
int l1
  ip address 8.8.8.8 255.255.255.255

 

2.  Configure a static default route on R2 pointing to R1

R2.

ip route 0.0.0.0 0.0.0.0 10.24.0.1

#Test: you can't ping 4.2.2.2 at this point because ISP doesn't have a route back to R2 since ISP doesn't know anything about 10.24.0.0/24 network. However, you can test ping to R1's serial port because R1 does know how to get back to R2.

 

 

3. Configure a static default route on R3 pointing to R2.

 

R3.


ip route 0.0.0.0 0.0.0.0 10.15.1.13

#Test: ping to R1's serial/WAN port

4. Option: using RIP for R2 and R3 rather than the static default routes.

R2.

no ip route 0.0.0.0 0.0.0.0 10.24.0.1

R3.

no ip route 0.0.0.0 0.0.0.0 10.15.1.13

R1.

router rip
default-information originate

#Test:

-Yu