Kubernetes Downward API Concepts
Kubernetes is exposing pod information to the containers running inside the pod through files or environment variables, which are projected in the container by a mechanism known as the Downward API. Individual pieces of information are declared as "items" under a "downwardAPI" volume declaration, and the corresponding content will be projected as individual files in the pod filesystem.
This is how the pod name and namespace can be projected as files available to containers running inside the pod.
Declare a "downwardAPI" volume, conventionally named "podinfo" and mount it in the pod:
apiVersion: v1 kind: Pod metadata: name: loop spec: containers: - name: loop image: docker.io/ovidiufeodorov/loop:latest volumeMounts: - name: "podinfo" mountPath: "/etc/podinfo" volumes: - name: podinfo downwardAPI: items: - path: "metadata/name" fieldRef: fieldPath: "metadata.name"
Note that individual downwardAPI items can declare a hierarchical path - the directories will be created automatically.