The following was used to upgrade an antiquated version of docker to the newest community edition on CentOS/RedHat linux:
/bin/cp -avf /etc/docker/ /etc/docker-bak/
yum install -y yum-utils
yum remove -y docker-1.* docker-common-2:1.*
yum-config-manager --add-repo https://download.docker.com/linux/centos/docker-ce.repo
yum install -y docker-ce docker-ce-cli containerd.io
usermod -a -G docker theserviceaccountusedfordocker
/bin/cp /etc/docker-bak/daemon.json /etc/docker/
systemctl start docker; systemctl enable docker