It is a controller that manages the deployment and scaling of a set of stateful pods that require stable network identities and stable storage volumes. StatefulSets are used to run stateful applications such as databases, where the order and uniqueness of each pod is important. StatefulSets provide unique stable network identities and stable storage volumes for each pod, which allows stateful applications to maintain data consistency even when they are scaled up or down, or when nodes fail or are replaced. StatefulSets are defined by a YAML file that includes a pod template, a service to access the pods, and other settings.
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