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Let's say I have two networks. One network is 10.241.0.1/24, and my
VMs are on that network. The other network is a provider network with
a CIDR of 192.168.100.0/22.

There's an illustration of what I mean here:

https://developer.rackspace.com/blog/neutron-networking-l3-agent/

Okay, so here's my question:
There's a router between the two networks. Is the routing being done
by a *physical* router, or by a *neutron* router?


Here's the reason that I ask:
When I set these networks up, I generally set up a neutron router
between the first network and the second network. But in my current
project, there's a physical router at 192.168.100.1. So it seems like
my Neutron router would be in conflict with the physical router at
192.168.100.1.

IE, I can't have two routers running on the same subnet. Or am I
missing something?