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Create a simple web services (of type NodePort), analogous to those encountered in the previous chapter but of type NodePort, that are listening on a HTTP server on port 80(for example the dashboard service present here). When you create a Service of type NodePort, Kubernetes makes your Service available on a randomly selected high port number (in the range 30000-32767) on all the nodes in your cluster.
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Using a browser or the curl command, you should be able to access the backend service by sending HTTP request to the domain name specified in the Ingress resource (remember to hook the hostname to the FIP in the /etc/hosts of the machine from which the request to the service starts)
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A speech remained pending. I'm talking about the ConfigMap manage-security-groups key. If set to true, a new group would appear in the Project/Network/SecurityGroups tab, containing the NodePorts of the implemented services (in this case the ports 31156 and 30458 of the coffee and tea services). In this way, the group can be associated with cluster instances. Why did I recommend setting the value to false? Because it would be useless, since the ports are already open. In fact, when installing Kubeadm (see "Preliminary steps" in cap. 2), it is recommended to open the range of ports 30000-32767 for WorkerNodes, which corresponds to the range in which a NodePort can be generated.