Merge pull request #40113 from shahiddev/master

Update terminology to remove the term "master"

Author: ktoliver

articles/aks/concepts-clusters-workloads.md

@@ -14,7 +14,7 @@ ms.author: mlearned
 
 As application development moves towards a container-based approach, the need to orchestrate and manage resources is important. Kubernetes is the leading platform that provides the ability to provide reliable scheduling of fault-tolerant application workloads. Azure Kubernetes Service (AKS) is a managed Kubernetes offering that further simplifies container-based application deployment and management.
 
-This article introduces the core Kubernetes infrastructure components such as the *cluster master*, *nodes*, and *node pools*. Workload resources such as *pods*, *deployments*, and *sets* are also introduced, along with how to group resources into *namespaces*.
+This article introduces the core Kubernetes infrastructure components such as the *control plane*, *nodes*, and *node pools*. Workload resources such as *pods*, *deployments*, and *sets* are also introduced, along with how to group resources into *namespaces*.
 
 ## What is Kubernetes?
 
@@ -24,41 +24,41 @@ You can build and run modern, portable, microservices-based applications that be
 
 As an open platform, Kubernetes allows you to build your applications with your preferred programming language, OS, libraries, or messaging bus. Existing continuous integration and continuous delivery (CI/CD) tools can integrate with Kubernetes to schedule and deploy releases.
 
-Azure Kubernetes Service (AKS) provides a managed Kubernetes service that reduces the complexity for deployment and core management tasks, including coordinating upgrades. The AKS cluster masters are managed by the Azure platform, and you only pay for the AKS nodes that run your applications. AKS is built on top of the open-source Azure Kubernetes Service Engine ([aks-engine][aks-engine]).
+Azure Kubernetes Service (AKS) provides a managed Kubernetes service that reduces the complexity for deployment and core management tasks, including coordinating upgrades. The AKS control plane is managed by the Azure platform, and you only pay for the AKS nodes that run your applications. AKS is built on top of the open-source Azure Kubernetes Service Engine ([aks-engine][aks-engine]).
 
 ## Kubernetes cluster architecture
 
 A Kubernetes cluster is divided into two components:
 
-- *Cluster master* nodes provide the core Kubernetes services and orchestration of application workloads.
+- *Control plane* nodes provide the core Kubernetes services and orchestration of application workloads.
 - *Nodes* run your application workloads.
 
-![Kubernetes cluster master and node components](media/concepts-clusters-workloads/cluster-master-and-nodes.png)
+![Kubernetes control plane and node components](media/concepts-clusters-workloads/control-plane-and-nodes.png)
 
-## Cluster master
+## Control plane
 
-When you create an AKS cluster, a cluster master is automatically created and configured. This cluster master is provided as a managed Azure resource abstracted from the user. There's no cost for the cluster master, only the nodes that are part of the AKS cluster.
+When you create an AKS cluster, a control plane is automatically created and configured. This control plane is provided as a managed Azure resource abstracted from the user. There's no cost for the control plane, only the nodes that are part of the AKS cluster.
 
-The cluster master includes the following core Kubernetes components:
+The control plane includes the following core Kubernetes components:
 
 - *kube-apiserver* - The API server is how the underlying Kubernetes APIs are exposed. This component provides the interaction for management tools, such as `kubectl` or the Kubernetes dashboard.
 - *etcd* - To maintain the state of your Kubernetes cluster and configuration, the highly available *etcd* is a key value store within Kubernetes.
 - *kube-scheduler* - When you create or scale applications, the Scheduler determines what nodes can run the workload and starts them.
 - *kube-controller-manager* - The Controller Manager oversees a number of smaller Controllers that perform actions such as replicating pods and handling node operations.
 
-AKS provides a single-tenant cluster master, with a dedicated API server, Scheduler, etc. You define the number and size of the nodes, and the Azure platform configures the secure communication between the cluster master and nodes. Interaction with the cluster master occurs through Kubernetes APIs, such as `kubectl` or the Kubernetes dashboard.
+AKS provides a single-tenant control plane, with a dedicated API server, Scheduler, etc. You define the number and size of the nodes, and the Azure platform configures the secure communication between the control plane and nodes. Interaction with the control plane occurs through Kubernetes APIs, such as `kubectl` or the Kubernetes dashboard.
 
-This managed cluster master means that you don't need to configure components like a highly available *etcd* store, but it also means that you can't access the cluster master directly. Upgrades to Kubernetes are orchestrated through the Azure CLI or Azure portal, which upgrades the cluster master and then the nodes. To troubleshoot possible issues, you can review the cluster master logs through Azure Monitor logs.
+This managed control plane means that you don't need to configure components like a highly available *etcd* store, but it also means that you can't access the control plane directly. Upgrades to Kubernetes are orchestrated through the Azure CLI or Azure portal, which upgrades the control plane and then the nodes. To troubleshoot possible issues, you can review the control plane logs through Azure Monitor logs.
 
-If you need to configure the cluster master in a particular way or need direct access to them, you can deploy your own Kubernetes cluster using [aks-engine][aks-engine].
+If you need to configure the control plane in a particular way or need direct access to it, you can deploy your own Kubernetes cluster using [aks-engine][aks-engine].
 
 For associated best practices, see [Best practices for cluster security and upgrades in AKS][operator-best-practices-cluster-security].
 
 ## Nodes and node pools
 
 To run your applications and supporting services, you need a Kubernetes *node*. An AKS cluster has one or more nodes, which is an Azure virtual machine (VM) that runs the Kubernetes node components and container runtime:
 
-- The `kubelet` is the Kubernetes agent that processes the orchestration requests from the cluster master and scheduling of running the requested containers.
+- The `kubelet` is the Kubernetes agent that processes the orchestration requests from the control plane and scheduling of running the requested containers.
 - Virtual networking is handled by the *kube-proxy* on each node. The proxy routes network traffic and manages IP addressing for services and pods.
 - The *container runtime* is the component that allows containerized applications to run and interact with additional resources such as the virtual network and storage. In AKS, Moby is used as the container runtime.