• KubeAPI server is a process running on master nodes that manages the cluster. The kubelet services running on each node communicate with the kube-apiserver to share information about each node in the cluster.
• When we interact with the cluster using kubectl tool, it sends API requests to KubeAPI server which then authenticates the request, checks if the user is authorized to perform the required action and then saves the state in etcd.
• It is the only component of the cluster that directly interacts with etcd. All the other components of the cluster (eg. scheduler or kubelet) use API server to interact with the cluster.
• When setting up the cluster from scratch, download the kube-api binary and run it as a service.
• If the cluster is set up using KubeAdmin, the kube-api server is automatically deployed as a static pod in the kube-system namespace on the master node. The config is present at /etc/kubernetes/manifests/kube-apiserver.yaml