The container file system is ephemeral. Files on the container’s file system exist only as long as the container exists. If a container is deleted or re-created in K8s, data stored on the container file system is lost.
Many applications need a more persistent method of data storage.
Volumes allow you to store data outside the container file system while allowing the container to access the data at runtime.
This can allow data to persist beyond the life of the container.
Volumes offer a simple way to provide external storage to containers within the Pod/container spec. Persistent Volumes are a slightly more advanced form of Volume. They allow you to treat storage as an abstract resource and consume it using your Pods.
Both Volumes and Persistent Volumes each have a volume type. The volume type determines how the storage is actually handled. Various volume types support storage methods such as: