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- CentOS 7 (minimum supported version);
- at least 2 GB of RAM and 2 CPUs per machine;
- opening doors on the control plane (6443, 2379-2380, 10250-10252) and on the worker (10250, 30000-32767);
- uniqueness uniqueness of MAC address and product_uuid for each node;
- complete connectivity between the cluster nodes;
- swap disabled on nodes.
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In order for a Linux node's iptables to correctly view bridged traffic (see here), verify that net.bridge.bridge-nf-call-iptables is set to 1 in your sysctl config
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