Hello Cameron
If I’m not mistaken, this is from the MPLS Layer 3 VPN Configuration lesson so I moved your post to this thread.
The behavior you are seeing is normal. You haven’t configured anything wrong. The purpose of such an implementation is to allow the remote networks to communicate with each other. You should be able to ping the 1.1.1.1 network from the 5.5.5.5 network using a ping on CE2 that uses the loopback as the source of the ping. Similarly, you should be able to ping the 5.5.5.5 network from 1.1.1.1, again using the local loopack as the source.
There is no requirement that the CE/PE/P routers should be able to ping each other. Indeed, under normal circumstances, the CE1 router should not be able to ping the Ge0/0 interface of the CE2 router or visa versa. See this NetworkLessons notes below:
- MPLS Layer 3 VPN communication between CE routers
- MPLS Layer 3 VPN communication between CE and PE routers
The same is true about the direct communication between P routers and the CE router networks. The role of the backbone network (PE and P routers) are to ensure that the next hop IP issued by BGP is reachable. That’s all, and that’s part of the benefits of MPLS. MPLS itself doesn’t need to know how to reach all networks or all routers, it just needs to be able to reach the next hop to make it work.
If there is no mask showing up that means that the classful subnet mask is being used. The classful subnet mask for this particular address is indeed 255.255.255.0. If you issue a network command with a mask that is different from the classful one, then it will appear in the running configuration.
I hope this has been helpful!
Laz