How to have topics publish and subscribe both ways between host and docker container?

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I have roscore running in docker. I have a bunch of topics, some are started by nodes inside the docker container, some are outside of the container, on host. I need some of these topics to subscribe to eachother. I can subscribe from host to topics that are inside docker and I can echo what's being published to them. But in the container I can't echo topics that are published on host.

For example, what I can do:
Inside docker: rostopic pub /dummy std_msgs/String "data: 'dummy text'" -r 10
On host: rostopic echo /dummy and I see dummy text being printed

What I can't do:
On host: rostopic pub /dummy std_msgs/String "data: 'dummy text'" -r 10
Inside docker: rostopic echo /dummy dummy text should be printed, but nothing is coming out

What I have tried:

• --net=host, -e ROS_IP=172.17.0.1 and -e ROS_MASTER_URI=http://172.17.0.1:11311 in in docker run which made the first part work (publish topic in docker and echo from host)
• modifiy /etc/hosts in docker container and on host
• all sorts of combinations for ROS_IP, ROS_MASTER_URI and ROS_HOSTNAME
• running roscore on host and setting ROS_IP, ROS_MASTER_URI and ROS_HOSTNAME accordingly

rostopic list works fine on host and in docker no matter where roscore runs. I can ping host from docker and vice versa. I also tested with netcat, both ways works fine, yet topics don't want to send data from host to docker.

In docker I have ros indigo (I can't decide what ros version is used) and on host I have melodic (I can install indigo if anyone thinks that might a problem).

UPDATE:
By using --net=host, ROS_IP=127.0.0.1 and ROS_MASTER_URI=http://localhost:11311 and running the subscriber from docker before the publisher from host I got it working. But this means subscriber must always run before publisher for my scripts to work.