Controller manager
The Kubernetes controller manager is a control-plane component that runs controllers to reconcile cluster resources with their desired state.
Acing the Certified Kubernetes Administrator Exam, Second Edition
kube-controller-manager is the Kubernetes control-plane component that runs controller processes regulating cluster state.
- How it is used
- Regulates desired and current cluster state through controllers managing Deployments, ReplicaSets, namespaces, service accounts, and access tokens.
- How deep it goes
- Explains reconciliation and operational placement, then applies logs, manifests, and pod inspection to failure diagnosis without detailing controller internals.
- Examples
- Uses Deployment replica scaling, Pending pods, kube-system listings, control-plane manifests, and crictl or kubectl logs during failures.
- What you can do after
- Diagnose/debug with kubectl, crictl, logs, describe output, and static-pod manifests when reconciliation or control-plane components fail.
Google Anthos in Action
kube-controller-manager is the Kubernetes control-plane component that runs controllers to reconcile cluster resources toward their desired state.
- How it is used
- Maintains Kubernetes resources in their declared state through continuously running reconciliation loops.
- How deep it goes
- Explains control-loop behavior, binary and thread structure, controller roles, and cloud-provider separation without deployment procedures.
- Examples
- Uses node status, Pod replication, Pod-to-Service endpoints, service accounts, routes, and cloud load balancers as controller responsibilities.
- What you can do after
- Evaluate how Kubernetes preserves desired resource state and distinguish internal controllers from provider-specific controllers.
Read how Google Anthos in Action explains controller manager →
Related concepts
- control plane nodepart of · A control plane node is a Kubernetes cluster machine that hosts components managing cluster state, exposing the cluster API, scheduling workloads, and coordinating operations.
- control loopuses · A control loop is a repeated process that observes a system’s state, compares it with a desired state, and uses feedback to guide corrective action.
- control planepart of · A control plane is the management and coordination part of a system that governs the configuration, policies, state, and operations of its components and resources.
- cloud controller managercontrasts with · The cloud controller manager is a Kubernetes control-plane component that runs controllers integrating cluster operation with an underlying cloud provider.
- goaluses · A goal is a desired outcome or state that an actor or system aims to achieve and that can guide action or evaluation.
- time zoneuses · A time zone is a geographic or rule-defined region whose local civil time is determined by offsets and calendar-time rules relative to a reference time standard.
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