如何在 Jenkins 中正确安装 docker？

Question

I'm running jenkins/jenkins image from dockerhub, I've installed the docker plugin, still not able to find docker inside a pipeline, what am i missing

pipeline {
  agent any

  stages {
    stage('Running') {
      agent {
        docker {
          image 'node:14-alpine'
        }
      }


      steps {
        echo 'preparing the flow'
      }
    }

    stage('Build') {
      agent {
        docker {
          image 'node:14-alpine'
        }
      }

      steps {
        sh """
          npm install
        """
      }
    }
  }
}

/var/jenkins_home/workspace/multibranch_PR-1@2@tmp/durable-5bf3a454/script.sh: 1: /var/jenkins_home/workspace/multibranch_PR-1@2@tmp/durable-5bf3a454/script.sh: docker: not found
[Pipeline] isUnix
[Pipeline] sh
+ docker inspect -f . hub.docker.com/node:14-alpine
/var/jenkins_home/workspace/multibranch_PR-1@2@tmp/durable-dea9bcb7/script.sh: 1: /var/jenkins_home/workspace/multibranch_PR-1@2@tmp/durable-dea9bcb7/script.sh: docker: not found
[Pipeline] isUnix
[Pipeline] sh
+ docker pull hub.docker.com/node:14-alpine
/var/jenkins_home/workspace/multibranch_PR-1@2@tmp/durable-b25ea3a8/script.sh: 1: /var/jenkins_home/workspace/multibranch_PR-1@2@tmp/durable-b25ea3a8/script.sh: docker: not found

Answer 1

The plugin is only a utility layer to use docker from your pipelines it does not install docker and still needs access to the docker socket.

Generally there a two ways to achieve this. Install docker inside the jenkins container (with apt) or mount the docker socket of the host inside the container. For the latter you can follow this