Customizing docker

Enable the remote API on a new socket

Create a file called /etc/systemd/system/docker-tcp.socket to make Docker available on a TCP socket on port 2375.

[Unit]
Description=Docker Socket for the API
[Socket]
ListenStream=2375
BindIPv6Only=both
Service=docker.service
[Install]
WantedBy=sockets.target

Then enable this new socket:

systemctl enable docker-tcp.socket
systemctl stop docker
systemctl start docker-tcp.socket
systemctl start docker

Test that it's working:

docker -H tcp://127.0.0.1:2375 ps