Routing Issue with Multiple Segments

[ccshack]

I have three networks that have been operating independently and now need merged. One building contains a Cisco 800 series router that routes all traffic for the wireless network (6 sites) all configured on the 192.168.X.X network and can only ping 192.168.X.X addresses. At this same location I have added a Cisco 3700 series router to connect this location to another location across town. This router contains an ethernet address on the 192.168.X.X and a second card on the 10.2.X.X address. From this router, I can ping any 192.168.X.X and any 10.X.X.X addresses on the WAN. On the third router across town I can ping any 10.X.X.X address but not any 192.168.X.X addresses. I feel like the issue is on the middle router with the 192.168 and 10.2 address. I can ping it from either side but not across it. I have not had to deal with passing traffic to different IP schemes before. Any input on how to do this would be greatly appreciated. Do I do it with VLAN's, bridging, not sure what?

 

[lgarner]

First question, does the crosstown router have a route to 192.168, and does the 800 router have a route to crosstown? Are you using a dynamic routing protocol?

 

[gtmoore]

Like lgarner said you will need routes on the crosstown router to the 192.168.x.x. Also on the crosstown router I am going to guess you have a LAN there too. You will need to put a static route in both the 800 and 3700 to reach the crosstown LAN.

If these are the only 3 networks you are probably better just using static routes with default gateways. Here is a quick example:

Crosstown router:
ip route 0.0.0.0 0.0.0.0 10.2.x.x(ip address of 3700 wan)

3700 router
ip route x.x.x.x(address of LAN on crosstown side) y.y.y.y(subnet mask of crosstown network) 10.2.z.z (address of crosstown router WAN interface)

800 Router
ip route 0.0.0.0 0.0.0.0 192.168.x.x (address of 3700 LAN interface)

Hope this helps.

Greg