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Determine RKE and Docker versions
Under RKE to use 17.03 anymore - grab the latest version Don't just use the latest docker version - check the RKE release page to get the version pair - 0.15/17.03 and 0.16/18.06 - see https://github.com/docker/docker-ce/releases - currently https://github.com/docker/docker-ce/releases/tag/v18.06.3-ce
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