text: **Ephemeral storage**
  Container images are stored locally on the nodes running Red Hat OpenShift Container 
  Platform pods. 
  
  When Docker run time is used, the /var/lib/docker mount point is used by active containers 
  and pods. This local storage is where the node maintains a copy of container images that are 
  pulled from a container registry. This mount point is managed by docker-storage and it uses 
  the following naming format: /var/lib/docker/overlay2/<layer-id> and 
  /var/lib/docker/containers/<container-id>. 
  
  **Persistent storage**
  Persistent Volume Claims (PVC) are used to store the application data. These claims can be 
  added to the environment manually or provisioned dynamically by using a StorageClass 
  object. 
  
  **Storage classes**
  The StorageClass resource object describes and classifies different types of storage that can 
  be requested. It also provides a means for passing parameters to the backend for dynamically 
  provisioned storage on demand. 
  
  StorageClass objects can also serve as a management mechanism for controlling different 
  levels of storage and access to the storage. Cluster Administrators (cluster-admin) or Storage 
  Administrators (storage-admin) define and create the StorageClass objects that users can 
  use without needing any intimate knowledge about the underlying storage volume sources. 
  Therefore, the naming of the storage class that is defined in the StorageClass object must be 
  useful in understanding the type of storage it maps, whether that is storage from PowerVC 
  Cinder or from other storage provider. 