25

Is there a way to programmatically get the name of the pod that a container belongs to in Kubernetes? If so how? I'm using fabric8's java client but curl or something similar will be fine as well.

Note that I don't want to find the pod using a specific label since then (I assume) I may not always find the right pod if it's scaled with a replication controller.

Johan
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2 Answers2

41

You can tell Kubernetes to put the pod name in an environment variable of your choice using the downward API.

For example:

apiVersion: v1
kind: Pod
metadata:
  name: dapi-test-pod
spec:
  containers:
    - name: test-container
      image: gcr.io/google_containers/busybox
      command: [ "/bin/sh", "-c", "env" ]
      env:
        - name: MY_POD_NAME
          valueFrom:
            fieldRef:
              fieldPath: metadata.name
        - name: MY_POD_NAMESPACE
          valueFrom:
            fieldRef:
              fieldPath: metadata.namespace
        - name: MY_POD_IP
          valueFrom:
            fieldRef:
              fieldPath: status.podIP
  restartPolicy: Never
Alex Robinson
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29

The pod name is written to /etc/hostname so it's possible to read it from there. In Java (which I'm using) you can also get the hostname (and thus the name of the pod) by calling System.getenv("HOSTNAME").

Johan
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    note that in some environments like IBM IKS 1.11 this will be `localhost` and not the name of the pod https://issues.jenkins-ci.org/browse/JENKINS-53297 – csanchez Oct 19 '18 at 09:42