how to make docker client connect to docker daemon over http

Question

I've got a host running docker daemon with those options:

dockerd -H tcp://0.0.0.0:2376 ...

From a remote host I want to connect to the docker API of this instance with docker-machine but I always get the following message:

http: server gave HTTP response to HTTPS client

My host is well responding over http:

root$ curl -v  http://10.228.38.30:2376/v1.15/version
* Hostname was NOT found in DNS cache
*   Trying 10.228.38.30...
* Connected to 10.228.38.30 (10.228.38.30) port 2376 (#0)
> GET /v1.15/version HTTP/1.1
> User-Agent: curl/7.38.0
> Host: 10.228.38.30:2376
> Accept: */*
> 
< HTTP/1.1 200 OK
< Content-Type: application/json
* Server Docker/1.12.3 (linux) is not blacklisted
< Server: Docker/1.12.3 (linux)
< Date: Wed, 14 Dec 2016 12:25:45 GMT
< Content-Length: 196
< 
{"Version":"1.12.3","ApiVersion":"1.24","GitCommit":"6b644ec","GoVersion":"go1.6.3","Os":"linux","Arch":"amd64","KernelVersion":"3.16.0-4-amd64","BuildTime":"2016-10-26T21:39:14.007365648+00:00"}
* Connection #0 to host 10.228.38.30 left intact

How to tell docker client (ie docker-machine here) to talk with the daemon over http and not https ?

I don't need https because I'm on a test environment.

Answer 1

First you need to configure your Docker daemon to use HTTP instead of HTTPS.

Then you can add a docker machine with a generic driver, something like this:

$ docker-machine create \
  --driver generic \
  --generic-ip-address=203.0.113.81 \
  --generic-ssh-key ~/.ssh/id_rsa \
  vm