Help Pining Router through Router.

[bstevenson11]

Hi There,

I am having trouble pinging a router through another router. router 4 is trying to ping router 3 through router 1, but can't seem to get it to work. The setup it as follows.

Router4 Int:

Ethernet0/0 - 192.168.0.2 255.255.255.0

Router1 Int:

FA0/0 - 192.168.0.1 255.255.255.0 

FA0/1 - 10.0.0.1 255.255.255.0

Router3 Int:

FA0/0 - 10.0.0.2 255.255.255.0 

I setup a route on router 4 as follows: ip route 10.0.0.0 255.255.255.0 192.168.0.1

I setup a route on router 3 as follows: ip route 192.168.0.0 255.255.255.0 10.0.0.1

Other than that I haven't setup anything else on the router. 

[Richard Burts]

You have given us some information but not enough for us to be able to identify the issue. Can you provide answers to give us more to work with?

- are these real routers and switches? Or is this some software emulated network?

- what model of router are these?

- how are the routers physically connected? Is it straight through cable or is it cross over cable?

- would you post output of show ip interface brief from each of the routers?

- would you post output of show ip route from each of the routers?

HTH

Rick

[bstevenson11]

Rick,

Thanks for the quick reply. These are simulated devices through the Boson Netsim software. I am unable to copy my configs for some reason at the moment, not sure why. I apologize for not being able to provide you with more specific info, but the router are 2811 and 3640 routers connected through Ethernet. From looking at the attached netmap I attached as an image in my post above, and with the little info I provided on the routes and configs of the routers, what would I generally need to do to allow Router4 on a different subnet to communicate with Router3 through Router1?

[Richard Burts · Accepted solution]

It is helpful to know that this is a simulated environment. What you have posted is a reasonable start, and in general should be sufficient to allow router 3 and router 4 to ping each others addresses. Each router should know its own connected subnets and router 3 and router 4 have an appropriate route to the remote subnet.

Since it is not working there are several things that we can check as possible sources of the problem (and these are what I was trying to get at with the questions that I asked). Here are some of the potential issues:

- are the interfaces not correctly connected (wrong type cable or some other physical connection issue).

- are the interfaces in the up/up state (are they perhaps shutdown)

- is ip routing enabled?

- are the local subnets in the routing table? (mostly dependent on interface is up/up)

- are the static routes to remote subnet in the routing table?

HTH

Rick

[bstevenson11]

Rick,

I made a mistake on one of the routes. I guess I forgot to save after creating it yesterday and assumed it was still there. I created the route and saved the config and communication is working great. 

Thanks!

[Richard Burts]

Glad to know that it is working great. And glad that you solved your own problem.

Config changes that are not saved and then go away have happened to all of us. So a question that is frequently useful when troubleshooting issues is: have there been recent config changes

HTH

Rick