Does Kubernetes mount an emtpyDir volume on the host?

Question

Kubernetes features quite a few types of volumes, including emptyDir:

An emptyDir volume is first created when a Pod is assigned to a Node,

Answer 1

You can list all emptyDir volumes on the host using this command

df

To view only volumes mapped to a specific volume

df | grep -i cache-volume

where cache-volume is the volume name in your pod definition

apiVersion: v1
kind: Pod
metadata:
  name: test-pd
spec:
  containers:
  - image: k8s.gcr.io/test-webserver
    name: test-container
    volumeMounts:
    - mountPath: /cache
      name: cache-volume
  volumes:
  - name: cache-volume
    emptyDir: {}

Answer 2

Yes it is also accessible on the node. It is bind mounted into the container (sort of). The source directories are under /var/lib/kubelet/pods/PODUID/volumes/kubernetes.io~empty-dir/VOLUMENAME

You can find the location on the host like this:

sudo ls -l /var/lib/kubelet/pods/`kubectl get pod -n mynamespace mypod -o 'jsonpath={.metadata.uid}'`/volumes/kubernetes.io~empty-dir