Learn Docker - Fundamentals of Docker 19.x - Second Edition

Pods and volumes

In Chapter 5, Data Volumes and Configuration, we learned about volumes and their purpose: accessing and storing persistent data. Since containers can mount volumes, pods can do so as well. In reality, it is really the containers inside the pod that mount the volumes, but that is just a semantic detail. First, let's see how we can define a volume in Kubernetes. Kubernetes supports a plethora of volume types, so we won't delve into too much detail about this. Let's just create a local volume implicitly by defining a PersistentVolumeClaim called my-data-claim:

apiVersion: v1kind: PersistentVolumeClaimmetadata:  name: my-data-claimspec:  accessModes:    - ReadWriteOnce  resources:    requests:      storage: 2Gi

We have defined a claim that ...