I have a Raspberry Pi on which I operate DNS, IDS/IPS servers. The way it is connected in the network and configured is as follows:
Internet -> Router -> Pi (eth0)
Pi is further configured as DNS server on the router.
Now, fundamentally this is fine if I were merely using Pi as a DNS server and it also seems to serve limited purpose in its role as an IDS/IPS on the network (since all outbound traffic is routed through Pi).
But I don't think this is the best network positioning for the Pi especially when it does nothing to block an internal threat- one where a compromised machine attacks another local machine.
I would like to configure it as below with the DHCP on the router itself-
Internet -> Router -> Pi -> All machines on the network
What would that setting be in the router to route all packets only through the Pi? Without wanting to expose the Pi to the internet ahead of the router itself, I would like your views on how to best configure the Pi within the network.