Multi-homed host breaks networking

I built an host to run ansible from. I made it a multi-homed host, following these instructions ( The point is to lock it down and limit access, since ansible has the keys to the kingdom.
I installed the AWX project (open source version of Tower,, which creates several containers.

My problem is that the containers can’t access anything off the host.
I’ve tried a couple of settings in my daemon.json file, but no joy.

"ip": "",
"default-gateway": "",
"bip": ""

I can’t find anything referencing multihomed hosts with docker at all. Anyone have any ideas here?