3.2.4 Docker Engine Requirements

Kubernetes is used to manage containers running on a containerization platform deployed on several systems. On Oracle Linux, Kubernetes is currently only supported when used in conjunction with the Docker containerization platform. Therefore, each system in the deployment must have the Docker engine installed and ready to run. Support of Oracle Linux Container Services for use with Kubernetes is limited to usage with the latest Oracle Container Runtime for Docker version available in the ol7_addons repository on the Oracle Linux yum server and in the ol7_x86_64_addons channel on ULN.

Please note that if you enable the ol7_preview repository, you may install a preview version of Oracle Container Runtime for Docker and your installation can no longer be supported by Oracle. If you have already installed a version of Docker from the ol7_preview repository, you should disable the repository and uninstall this version before proceeding with the installation.

Install, the Docker engine on all nodes in the cluster:

# yum install docker-engine

Enable the Docker service in systemd so that it starts on subsequent reboots and you should start the service before running the kubeadm-setup.sh tool.

# systemctl enable docker
# systemctl start docker

See Oracle® Linux: Oracle Container Runtime for Docker User's Guide for more information on installing and running the Docker engine.