I have docker installed on CentOS 7 and I am running firewallD.
From inside my container, going to the host (default 172.17.42.1)
With firewall on
container# nc -v 172.17.42.1 4243 nc: connect to 172.17.42.1 port 4243 (tcp) failed: No route to host
with firewall shutdown
container# nc -v 172.17.42.1 4243 Connection to 172.17.42.1 4243 port [tcp/*] succeeded!
I've read the docs on firewalld and I don't fully understand them. Is there a way to simply allow everything in a docker container (I guess on the docker0 adapter) unrestricted access to the host?