install docker cent os code example

Example 1: install docker centos 8

dnf config-manager --add-repo=https://download.docker.com/linux/centos/docker-ce.repo

Example 2: install docker centos 7

$ sudo yum remove docker \
                  docker-client \
                  docker-client-latest \
                  docker-common \
                  docker-latest \
                  docker-latest-logrotate \
                  docker-logrotate \
                  docker-engine