I installed Docker-ce(ver 17.03.1-ce-mac12 17661) on macOS Sierra(ver 10.12.5)
I created a container and run a simple socket echo server. And then attempted to connect to the container's echo server from the host.
Initially, when the number of open sockets reached 370, a connection failure occurred, I found the following via Google search.
https://github.com/docker/for-mac/issues/1009
To summarize, the docker for mac has its own maximum number of connections. I modified the maximum number of connections moderately according to this content.
And I connected to the docker host in the following way.
http://pnasrat.github.io/2016/04/27/inside-docker-for-os-x-ii
I changed the ulimit configuration of the docker host as well, and changed the osx and container settings accordingly.
And again, I tried again, but this time the number of sockets exceeded the 370 limit mentioned above, but it is also blocked at about 930 ~ 940.
I try to change the settings like this, but it does not get better.
Note that a docker running on top of an Ubuntu server does not need to change any settings, and works well without any socket restrictions.
An echo server running inside the container of a docker running on Ubuntu can maintain at least 4000 sockets.
The problem only occurs with the docker for mac.
If you are aware of this situation, can anyone suggest a solution? Thank you.