Storage
Persistent Volume
PV is an object representing storage. It is independent of any single pod and doesn’t belong to any namespace (alike node).
PVC results in a mapping of a PV to a pod (within a namespace). The request PV will be bind-mounted to the container itself
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
name: thisclaim
spec:
accessModes:
- ReadWriteOnce (1)
resources:
requests:
storage: 8Gi| 1 | “ReadWriteOnce” tells Kubernetes that this storage can only be mounted by a single container host in read-write mode In contrast “ReadWriteMany” tells Kubernetes that the storage can be mounted from multiple containers on different hosts. |
Static provisioning
With static provisioning, PVs are created beforehand by an administrator and expected to match a future claim.
Dynamic provisioning
Provider -StorageClass- knows how to provision storage on-the fly when a request comes in.
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: fast
provisioner: kubernetes.io/glusterfs
parameters:
resturl: "http://127.0.0.1:8081"
restauthenabled: "true"
restuser: "admin"
secretNamespace: "default"
secretName: "heketi-secret"PVCs referring to that particular storage class will get their PV objects created on-demand in a completely transparent fashion.