title: yum install older version docker
body: <p>I'm using centos7. And a few months ago I install docker 1.12 by running <code>docker install dokcer</code>. Recently, I still use this command and I get docker  1.13. I found yum update extra repo with dokcer 1.13. However I need dokcer 1.12. How can I install the older version 1.12 with yum extra repo? Is there any archive repo I can use ? I don't want to install docker 1.12 through docker's repo.</p>