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- CentOS 7 (minimum supported version);
- at least 2 GB of RAM and 2 CPUs per machine;
- install Docker on the nodes (https://docs.docker.com/engine/install/centos/);
- opening doors on the control plane (6443, 2379-2380, 10250-10252) and on the worker (10250, 30000-32767);
- install Docker on the nodes (https://docs.docker.com/engine/install/centos/);
- complete connectivity between the cluster nodes and uniqueness of MAC address and product_uuid for each node;
- swap disabled on nodes.
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