Ubuntu
$ curl -fsSL https://apt.dockerproject.org/gpg | sudo apt-key add -
$ sudo apt-key fingerprint 0EBFCD88
$ sudo apt-add-repository "deb https://apt.dockerproject.org/repo ubuntu-$(lsb_release -cs) main"
$ sudo apt-get update
$ apt-cache madison docker-ce
$ sudo apt-get install docker-ce=<VERSION_STRING> docker-ce-cli=<VERSION_STRING> containerd.io
CentOS
$ sudo curl -SsL https://download.docker.com/linux/centos/docker-ce.repo -o /etc/yum.repos.d/docker-ce.repo
$ sudo yum --showduplicates list docker-ce
$ sudo yum install docker-<VERSION_STRING> docker-ce-cli-<VERSION_STRING>