Routing

Note: The descriptions for each interface should be ignored. Fast Ethernet 0/0 is not the path to the ISP any longer; Ethernet1/0 is.

Just a question on how your hosts are configured. Do you have a default gateway configured on all of the hosts? If not that could explain being able to ping your local router interface while not being able to ping hosts in the other subnets.

A routing protocol won't help you in your situation. All three of the subnets you're trying to reach are directly connected subnets from the perspective of the router.

-Dan

Sounds like the hosts on the networks don't have routes to the other network/default gateway.

Chris.

Thanks for your input!

My hosts are configured to DHCP from another router. I understand what you mean, and will attempt to correct that issue at the next opportunity (I am only able to work on this once a week; all of this is a volunteer effort at a local youth center).

Thanks again,

nbuuck

Here's an update with a diagram to help better illustrate my situation (this is not the actual application, but the test environment I have setup here at home):

Diagram

Desktop 3: Able to get to the ISP, WWW, and the c3620 @ 192.168.0.2 but not beyond to 10.10.100.1. LinkSys : Same connectivity as Desktop 3. c3620 : Can communicate with all hosts on the 10.10.100.0/24 network, but not on the 192.168.0.0/24. Desktop 1: Can reach the router at 10.10.100.1, not beyond. Desktop 2: Same connectivity as Desktop 1.

I have attempted to add static routes in the following form:

c3620# (conf-t) ip route 192.168.0.0 255.255.255.0 192.168.0.1 c3620# (conf-t) ip route 0.0.0.0 255.255.255.255 192.168.0.1

However, these measures have no effect. I must be missing something generally basic, but I cannot figure out what. Any further help would be greatly appreciated.

First, you do not need that first static route above. The cisco router will know how to get to directly connected networks, and will send out an arp on those networks when it has traffic destined for a node there. You will however need to keep that static default route.

Second, your problem is that your linksys router does not have a route to the 10.10.100.1 network. Linksys routers by default will only get a default route from their internet/wan port, and therefore nothing on

192.168.0.X knows how to get to 10.10.100.x. You need to put a static route on the Linksys that points to 192.168.0.2 for 10.10.100.0/24.

One more note, you need to add a route (on your internet/wan router) to 10.10.100.0/24 via 172.16.15.2, or whatever your linksys wanIP is. As he will not know how to get to 10.10.100.0/24 either......

In a test environment in which these neighboring routers were not present, these problems still occurred. The router would not even route between the two directly-connected networks. Will the measures that you suggested still overcome this issue?

Sadly, there was a firewall issue that made it seem as if there was no route to the hosts I was attempting to ping - sorry. I'm still working on getting the default route to the WWW (i.e. the provider's first hop), but this has been very helpful.

Thanks all. If I find that I'm unsuccessful in my attempts to get the default route working, I'll know where to go (which reminds me, should the Gateway of last resort be defined in the router configuration?).

Alright, I'm having a bit of an issue with the route out to the WWW. To get anywhere up or through my ISP's network, I have to statically define the route all the way up the hierarchy of private networks.

I've enabled RIP and added all of the networks and neighbors of which I'm aware, but nothing has changed.

Configuration:

Any ideas?

Also, what are the capabilities of a Cisco Fast Ethernet interface? Does it have the same capabilities as an Ethernet interface?

Ethernet is 10 meg, FastE is 100 meg, no other notable differences...

Your cisco box is not the problem. Its everything above it. Your cisco box has interfaces in 192.168.0.0/24 and 10.10.100.0/24. So long as it has a default gateway to get to any other networks (via

192.168.0.1), then anything connected behind the cisco box should box (provided you don't add other networks).

The issue is that once traffic gets into the 192.168.0.0/24 network or beyond, it does not know how to get back to 10.10.100.0/24. Your internet router for example (172.16.15.1). It knows how to get to

172.16.15.X (whatever you wan IP is), and all of your connections behind that are natted. Therefore, and I was wrong here yesterday, because you are running NAT, your internet router doesn't have to know anything.

The core of your issue is the linksys router. The cisco router passes

10.10.100.0/24 traffic to the linksys router, but it is not NATed according to your config. Therefore, the linksys router is getting a source address of 10.10.100.0/24 which it does not have in its route table. So the linksys will route traffic out the internet, but once the internet sends it back to the linksys, the linksys doesn't know to send it to the cisco router. I'm hoping this makes sense.....

Either: A) Put a static route on the linksys to 10.10.100.0/24 through

192.168.0.2 B) Enable rip on the cisco router for both networks and enable rip on the linksys and make sure they are exhanging routes (more important that the linksys is getting routes from the cisco, not the other way around) C) consider using NAT on the cisco router.

Thanks to all that have contributed. I have finally built a successful route and the network is now fully operational. I greatly appreciate all of your help.