kubeconfig

Kubeconfig is a configuration file used by Kubernetes clients, most notably kubectl, to access one or more Kubernetes clusters. It stores the network location of cluster API servers, the credentials used to authenticate, and the contexts that define a combination of cluster, user, and namespace. A kubeconfig enables seamless switching between different clusters and user accounts from a single file or set of files.

The kubeconfig file has a YAML structure with four main sections: clusters, users, contexts, and current-context. Each entry in clusters provides a name and connection details such as the API server URL and certificate authority data or a path to a certificate. Each entry in users contains authentication information, which can include client certificates, tokens, username/password, or an external exec command. Contexts bind together a cluster and a user, and may specify a default namespace. The current-context field selects which context is active by default when kubectl runs.

Location and management: by default, kubectl looks for the kubeconfig file at ~/.kube/config. The KUBECONFIG environment variable can extend or override this behavior by listing one or more file paths, which kubectl merges in order, with later files taking precedence. Users typically manage kubeconfig with kubectl config subcommands (for example, view, use-context, set-context, set-cluster, set-credentials) or by generating the file via cluster setup tools. kubeconfig is usable by other Kubernetes clients as well, not just kubectl, as long as the appropriate paths and credentials are provided.

Security considerations: kubeconfig contains sensitive credentials and should be stored with restricted permissions (for example, 600) and kept out of version control unless securely managed. When possible, rotate credentials and use separate files for different environments to minimize risk.