docker client (docker 1.12/centos) http: server gave HTTP response to HTTPS client

http docker

It needs to explicitly define that your registry is not secure:

{  ..  "insecure-registries" : [    "10.10.2.1:2376"  ],  ..}

sudo service docker restart

http docker

Port 2376 is for TLS communication.Use port 2375 instead.

DOCKER_HOST=tcp://10.10.2.1:2375

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