Configuring static routes at the network edge

Question

We have some Cisco 1750 routers at the edge of our network which are running RIP. We were advised to use static routes on the router, since there was only one route (across a WAN link) for traffic to go from the hub connected to the router, as RIP would only waste the limited bandwidth to the router. We posted this problem previously and got a response which stated :You could set up a default static route on your edge router, run RIP on your internal routers in order to propagate the default, but block the RIP to the outside.
On your edge router, make a default route to your external link. Keep RIP running as before, but add the line redistribute static in your rip configuration. That will get the default route propagated.
Now to stop the RIP on the external interface: If the link is on a different major IP network to your internal network, you can simply not include it in the network commands under rip. But if it is in the same network, then RIP will be enabled on the interface, so you will have to add passive-interface xxxxx, where xxxxx refers to the interface carrying your external link,
Alternatively, you could define your default route using the ip default-network command. This will get propagated automatically into the RIP even without the redistribute command.
We tried it, the problem is that the router is unreachable, via the serial or Ethernet, although if connected to the router via console port, with the configuration screen , you are able to ping external locations, and are able to telnet into the router, but he PC's on the Ethernet side of the router cant see the network.
Assistance\Advice requested.
attached you wll find , the actual reply , and a copy of some info from our work file.

Answer 1

Ernie
I have looked at the config that you posted and I see several issues. The serial interface on Salvage is 172.20.2.2. Your message indicates that it is connected via serial to a 3640 which your message seems to indicate is 172.20.1.4. But that makes the 3640 on a different subnet. Connections over a serial link should be in the same subnet on both ends. (The exception to that is when you are using the ip unnumbered feature - which you are not). I suspect that part of your problem is that the routers do not see themselves on a connected subnet. When you run RIP over the link it can compensate for that to some degree. But when you stop RIP the problem has impact.
Also I see that you have a static default route as Kevin suggested. And in RIP you have redistribute static. But there is no default metric defined. To redistribute into RIP you need a default metric. Another aspect of the problem with the default route is that the next hop for the default route is 172.20.1.4, but without RIP running I believe that Salvage has no idea how to get to that address. You can confirm this by doing show ip route 172.20.1.4 on Salvage. I suspect that you will get an error about route not in table.
Beyond these issues I believe that there is a larger problem of misunderstanding. When I look at your original post in this thread it talks about not running RIP over the serial link. And when I read Kevin's response the first paragraph is describing not running RIP over the serial interface when it says do static default on your edge router and run RIP on your internal router. If you are not running RIP over the serial interface then I see no reason to run RIP on Salvage at all. There is one piece of this that Kevin did not address. If you do not run RIP over the serial link then how does the 3640 know about the Ethernet subnet at Salvage. I believe that the answer is that the 3640 needs to configure a static route to 172.20.27.0 with the 1750 serial interface as the next hop. And if there are other routers that the 3640 communicates with via RIP then the 3640 needs to redistribute static into RIP (remembering to have a default metric).
If you address these issues I believe that you will have connectivity from the central network to the remote subnet on Salvage.
HTH
Rick