We've got multiple routers in our organisation and i can't get routing working as expected.
We have the following routers.
The problem is this.
If R5 int g2 is in a shutdown state, NAT works correctly throughout the network. Specifically computers on the 172.16.0.0/24 network that are using R4 as a gateway are able to browse the internet going through R4, R3, R2 and R1 (which is the border router).
However, when I bring R5 int g2 up (i.e. the interface which has a public ip on it), but which I don't to use as a default gateway, i find that internet traffic on the internal 172.16.0.0/24 network stops. When i run a traceroute, I find that traffic is trying to go out via R4, R3, R5 instead.
So the question is, would can i force traffic via R1/Nat router rather than R5?
There are at least 2 issues in this post which make it difficult to give you good advice.
The first issue is that you tell us that you have a /28, that you want to use an address from this subnet on R1 connecting to the ISP and that you want to use another address from this subnet on R5. How can you have /1 on R1 and .2 on R5?
The second issue is that obviously you are attempting to disguise your addressing. But you make it very difficult for us to understand your environment and to give you helpful advise. You tell us that you have a /28 block of addresses. Then you tell us that
Has a public ip on 100.x.x.1 with a default gateway of 100.x.x.254
Unfortunately .1 and .254 do not fit into a /28. If we can not trust this how can we trust anything else that you tell us?
Please start over again. Please give us a drawing showing the devices and how they are connected, and the subnets found on each device.
I'll make a better attempt. Sorry for the confusion
ip block is more like this:
100.x.x.10 - 100.x.x.14
gateway is 100.x.x.9
We are using
100.x.x.13 for R1
100.x.x.14 for R5
I've been discussing this locally and it seems some method of adding cost to a route would be the way to go. I will investigate this going forwards
I am still not clear about the topology of this network and not clear how you are using .13 for R1 and .14 for R5. Perhaps a diagram might clarify this. Or posting the configuration of the router interfaces for R1 and R5 might help.