dockerfile jenkins:latest -> jenkins/jenkins:latest

Hi,

I ran your docker container this way

docker run --net=isolated_nw
-e DOCKER_API_VERSION='1.23'
-p 88:8080 -p 50000:50000
-v /var/run/docker.sock:/var/run/docker.sock
-v /volumes/jenkins/jenkins_home:/var/jenkins_home
-v /volumes/jenkins/ansible_inventory:/etc/ansible
--hostname=jenkins --name jenkins
-d stefanprodan/jenkins

As my docker version is Docker version 1.11.2, build bac3bae and running on CoreOS stable, i checked there https://docs.docker.com/engine/reference/api/docker_remote_api/ and have guessed i should specify '1.23' for the environment variable DOCKER_API_VERSION.

When running the build job from the Pipeline sample you provide by your groovy script, i can see this in the Console Output

Started by user admin
[Pipeline] node
Running on master in /var/jenkins_home/workspace/Test pipeline
[Pipeline] {
[Pipeline] stage
[Pipeline] { (aspnetcore)
[Pipeline] sh
[Test pipeline] Running shell script

• docker inspect -f . microsoft/aspnetcore-build

Cannot connect to the Docker daemon. Is the docker daemon running on this host?
[Pipeline] sh
[Test pipeline] Running shell script

• docker pull microsoft/aspnetcore-build
  Using default tag: latest
  Warning: failed to get default registry endpoint from daemon (Cannot connect to the Docker daemon. Is the docker daemon running on this host?). Using system default: https://index.docker.io/v1/
  Cannot connect to the Docker daemon. Is the docker daemon running on this host?
  [Pipeline] }
  [Pipeline] // stage
  [Pipeline] }
  [Pipeline] // node
  [Pipeline] End of Pipeline
  ERROR: script returned exit code 1
  Finished: FAILURE

I'm getting nothing relevant using docker logs jenkins.

I can assure you that /var/run/docker.sock is a valid path as the ls -lah /var/run/d* command returns me this

-rw-r--r--. 1 root root 4 Nov 4 20:05 /var/run/docker.pid
srw-rw----. 1 docker docker 0 Nov 4 20:05 /var/run/docker.sock

So i guess CoreOS is not different enough from other systems to cause the issue, don't you think ?
Moreover there's this ls -lah /var/run/d* command result executed in the precedently ran container ( passed thanks to this command docker exec -it jenkins /bin/bash)

srw-rw----. 1 233 233 0 Nov 4 20:05 /var/run/docker.sock
The user or group "233" are unknown (can't see anything like that when i cat /etc/passwd or cat /etc/group, no need to copy their content here i think).

docker -v displays Docker version 1.12.3, build 6b644ec from within the container