Controller: The management node of a cloud environment. Typically, you have one controller per cloud region or more in high-availability (HA) environments. The controller manages all subsequent models in each environment.
Kubectl: The command line configuration tool for Kubernetes.
Kubelet: A service that runs on nodes and reads the container manifests to ensure the defined containers are started and running.
Node: Either bare metal or virtual machines that host the Kuberenetes orchestration system and application workloads.
Master: The node on which the Kubernetes control plane is installed.
Agent: These are nodes that host application workloads orchestrated by Kubernetes.The Kubernetes master controls them.
Pod: A group of one or more containers deployed to a single node. All containers in a pod share an IP address, IPC (interprocess communication), hostname, and other resources. This ensures you can move containers around the cluster more easily.
Replica Set: This controls how many identical copies of a pod you can have in a cluster.
Service: This decouples work definitions from the pods. Kubernetes service proxies automatically get service requests to the right pod—no matter where it moves to in the cluster or even if it’s been replaced.
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