title: Docker Plugin for Jenkins Pipeline - No user exists for uid 1005
body: <p>I'm trying to execute an SSH command from inside a Docker container in a Jenkins pipeline. I'm using the <a href="https://wiki.jenkins-ci.org/display/JENKINS/CloudBees+Docker+Pipeline+Plugin" rel="noreferrer">CloudBees Docker Pipeline Plugin</a> to spin up the container and execute commands, and the <a href="https://plugins.jenkins.io/ssh-agent" rel="noreferrer">SSH Agent Plugin</a> to manage my SSH keys. Here's a basic version of my Jenkinsfile:</p>
  
  <pre><code>node {
    step([$class: 'WsCleanup'])
    docker.image('node').inside {
      stage('SSH') {
        sshagent (credentials: [ 'MY_KEY_UUID' ]) {
          sh "ssh -vvv -o StrictHostKeyChecking=no ubuntu@example.org uname -a"
        }
      }
    }
  }
  </code></pre>
  
  <p>When the SSH command runs, I get this error:</p>
  
  <pre><code>+ ssh -vvv -o StrictHostKeyChecking=no ubuntu@example.org uname -a
  No user exists for uid 1005
  </code></pre>