I officially hate how Docker handles host firewalls. I probably said that before, and i'm saying it again, and I'll probably say it in the future! I went to put in a DROP rule for a bad acting IP in the DOCKER-USER chain, just as its stupid documentation says, did iptables-restore < /etc/iptables/rules.v4, and all communication with the server instantly went away. Had to reboot the box to get things working again. Completely ridiculous!