I have a server with docker that hosts 2 docker containers. These containers are running a Spring boot 2 application. In 1 container I want to connect to the other container and I am having timeout issues. The reason has to do with iptables. When I set the input policy to ACCEPT then everything works however when I set the INPUT policy to drop I get a timeout exception.
Container 1 is trying to connect to container 2 through the outside domain name. So Container 1 tries and connects to subdomain.domain.com. I beleive this means that docker eventually connects through eth0 instead of through docker internally. Is this the reason that the container cant connect to the other container and I must set the INPUT policy to ACCEPT?
How can I setup iptables so that a docker container may connect to another docker container if using the "outside" domain name?
You can also make the two containers as part of service stack and either link the containers or even possibly create a separate network and then link the containers thereby isolating the two containers.
This link provides a simple example