title: Dockerfile Unknown flag: chown
body: <p>My Dockerfile is failing on the below step: </p>
  
  <pre><code>ADD --chown=user:user test.py /etc/test
  </code></pre>
  
  <p>Any suggestions on how can I fix it? I am using AWS EC2 instance RHEL 7.6
  Updating with docker version output below:</p>
  
  <pre><code>Client:
   Version:         1.13.1
   API version:     1.26
   Package version: docker-1.13.1-88.git07f3374.el7.x86_64
   Go version:      go1.10.2
   Git commit:      07f3374/1.13.1
   Built:           Thu Dec  6 07:01:49 2018
   OS/Arch:         linux/amd64
  
  Server:
   Version:         1.13.1
   API version:     1.26 (minimum version 1.12)
   Package version: docker-1.13.1-88.git07f3374.el7.x86_64
   Go version:      go1.10.2
   Git commit:      07f3374/1.13.1
   Built:           Thu Dec  6 07:01:49 2018
   OS/Arch:         linux/amd64
   Experimental:    false
  </code></pre>
  
  <p>Please advice on how to update to more latest verison of docker if that's the issue</p>