Kubernetes PV ve PVC AccessModes Uyumu

Giriş

Şeklen şöyle

Açıklaması şöyle

ReadWriteOnce (RWO): This is the default access mode. It allows the PVC to be mounted as read-write by a single node in the cluster. This means that the PVC can be used by a single pod running on that node and is not available to other nodes in the cluster.

ReadOnlyMany (ROX): This access mode allows the PVC to be mounted as read-only by many nodes in the cluster. This means that the PVC can be used by multiple pods running on different nodes, but they can only read from it, not write to it.

ReadWriteMany (RWX): This access mode allows the PVC to be mounted as read-write by many nodes in the cluster. This means that the PVC can be used by multiple pods running on different nodes, and they can both read from and write to it.

ReadWriteOncePod: The ReadWriteOncePod storage class is a pre-defined storage class that can be used to create a persistent volume with ReadWriteOnce access mode that is intended to be used by a single pod. Kubernetes ensures that pod is the only pod across your whole cluster that can read that PVC or write to it.

Örnek

3 tane PV şöyle olsun. Hepsi hostPath kullanıyor. 

1. ReadOnlyMany

2. ReadWriteMany

3. ReadWriteOnce

apiVersion: v1
kind: PersistentVolume
metadata:
  name: my-pv-rox
spec:
  storageClassName: standard
  capacity:
    storage: 5Gi
  accessModes:
    - ReadOnlyMany
  hostPath:
    path: /data/my-pv-rox

apiVersion: v1
kind: PersistentVolume
metadata:
  name: my-pv-rwx
spec:
  storageClassName: standard
  capacity:
    storage: 5Gi
  accessModes:
    - ReadWriteMany
  hostPath:
    path: /data/my-pv-rwx

apiVersion: v1
kind: PersistentVolume
metadata:
  name: my-pv-rwo
spec:
  storageClassName: standard
  capacity:
    storage: 5Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: /data/my-pv-rwo

Bunlarla uyumlu 3 tane PVC yaratmak için şöyle yaparız.  Hepsinin storageClassName ismi standard ve accessModes şöyle

1. ReadOnlyMany

2. ReadWriteMany

3. ReadWriteOnce

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc-rox
spec:
  storageClassName: standard
  accessModes:
    - ReadOnlyMany
  resources:
    requests:
      storage: 1Gi

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc-rwx
spec:
  storageClassName: standard
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Gi

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc-rwo
spec:
  storageClassName: standard
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi