Cannot connect to the Docker daemon at tcp://XX.XX.XX.XX:2375

Hi,
trying to get my docker up and running for days now.
I use a vagrant / ubuntu host.
I cannot connect to my docker management port 2375 in any case I tryied.
This is the sequence of commands I use, any help would be great.

vagrant init ubuntu/xenial64

vagrant ssh

wget -qO- https://get.docker.com/ | sh

sudo usermod -a -G docker ubuntu

{Logout / Login}

docker info

Containers: 0
Running: 0
Paused: 0
Stopped: 0
Images: 0
Server Version: 17.04.0-ce
Storage Driver: aufs
Root Dir: /var/lib/docker/aufs
Backing Filesystem: extfs
Dirs: 0
Dirperm1 Supported: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins:
Volume: local
Network: bridge host macvlan null overlay
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary:
containerd version: 422e31ce907fd9c3833a38d7b8fdd023e5a76e73
runc version: 9c2d8d184e5da67c95d601382adf14862e4f2228
init version: 949e6fa
Security Options:
apparmor
seccomp
Profile: default
Kernel Version: 4.4.0-72-generic
Operating System: Ubuntu 16.04.2 LTS
OSType: linux
Architecture: x86_64
CPUs: 2
Total Memory: 992.2MiB
Name: ubuntu-xenial
ID: W4NP:S7RE:K2UK:JA4B:FUSJ:G4XA:BSGL:WYYE:NNXT:G3E7:JFMB:3ZEK
Docker Root Dir: /var/lib/docker
Debug Mode (client): false
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Experimental: false
Insecure Registries:
127.0.0.0/8
Live Restore Enabled: false

ifconfig

docker0 Link encap:Ethernet HWad
dr 02:42:bb:2b:cf:5f
inet addr:172.17.0.1 Bcast:0.0.0.0 Mask:255.255.0.0
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

enp0s3 Link encap:Ethernet HWaddr 02:03:81:8c:20:c6
inet addr:10.0.2.15 Bcast:10.0.2.255 Mask:255.255.255.0
inet6 addr: fe80::3:81ff:fe8c:20c6/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:156692 errors:0 dropped:0 overruns:0 frame:0
TX packets:23837 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:201647295 (201.6 MB) TX bytes:1619619 (1.6 MB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:20 errors:0 dropped:0 overruns:0 frame:0
TX packets:20 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1
RX bytes:1000 (1000.0 B) TX bytes:1000 (1000.0 B)

docker -H 10.0.2.15 info
Cannot connect to the Docker daemon at tcp://10.0.2.15:2375. Is the docker daemon running?