Have you tried this ? node.ml
Set to true (default) to identify the node as a machine learning node.
If set to false in elasticsearch.yml, the node cannot run jobs. If set to true but xpack.ml.enabled is set to false, the node.ml setting is ignored and the node cannot run jobs. If you want to run jobs, there must be at least one machine learning node in your cluster.xpack.ml.enabled
Set to true (default) to enable machine learning on the node.
If set to false in elasticsearch.yml, the machine learning APIs are disabled on the node.