Se la tua classe di archiviazione non supporta il provisioning dinamico del volume, devi creare manualmente PV e PVC associati , utilizzando i file yaml, volumeClaimTemplates consentirà di collegare le PVC esistenti ai pod del tuo statefulset.
Ecco un esempio funzionante:https:/ /github.com/k8s-school/k8s-school/blob/master/examples/MONGODB-install.sh
Dovresti:
- eseguilo in locale su https://kind.sigs.k8s.io/ , che supportano il provisioning dinamico del volume, quindi qui PVC e PV verranno creati automaticamente
- esporta file yaml di PV e PVC
- utilizza questi file yaml come modello per creare PV e PVC per il tuo backend NFS.
Ecco cosa otterrai su Kind:
$ ./MONGODB-install.sh
+ kubectl apply -f 13-12-mongo-configmap.yaml
configmap/mongo-init created
+ kubectl apply -f 13-11-mongo-service.yaml
service/mongo created
+ kubectl apply -f 13-14-mongo-pvc.yaml
statefulset.apps/mongo created
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
mongo-0 2/2 Running 0 8m38s
mongo-1 2/2 Running 0 5m58s
mongo-2 2/2 Running 0 5m45s
$ kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
database-mongo-0 Bound pvc-05247511-096e-4af5-8944-17e0d8222512 1Gi RWO standard 8m42s
database-mongo-1 Bound pvc-f53c35a4-6fc0-4b18-b5fc-d7646815c0dd 1Gi RWO standard 6m2s
database-mongo-2 Bound pvc-2a711892-eeee-4481-94b7-6b46bf5b76a7 1Gi RWO standard 5m49s
$ kubectl get pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
pvc-05247511-096e-4af5-8944-17e0d8222512 1Gi RWO Delete Bound default/database-mongo-0 standard 8m40s
pvc-2a711892-eeee-4481-94b7-6b46bf5b76a7 1Gi RWO Delete Bound default/database-mongo-2 standard 5m47s
pvc-f53c35a4-6fc0-4b18-b5fc-d7646815c0dd 1Gi RWO Delete Bound default/database-mongo-1 standard 6m1s
E un dump di un PVC (generato qui da volumeClaimTemplate a causa del provisioning del volume dinamico strano):
$ kubectl get pvc database-mongo-0 -o yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
annotations:
pv.kubernetes.io/bind-completed: "yes"
pv.kubernetes.io/bound-by-controller: "yes"
volume.beta.kubernetes.io/storage-provisioner: rancher.io/local-path
volume.kubernetes.io/selected-node: kind-worker2
creationTimestamp: "2020-10-16T15:05:20Z"
finalizers:
- kubernetes.io/pvc-protection
labels:
app: mongo
managedFields:
...
name: database-mongo-0
namespace: default
resourceVersion: "2259"
selfLink: /api/v1/namespaces/default/persistentvolumeclaims/database-mongo-0
uid: 05247511-096e-4af5-8944-17e0d8222512
spec:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 1Gi
storageClassName: standard
volumeMode: Filesystem
volumeName: pvc-05247511-096e-4af5-8944-17e0d8222512
status:
accessModes:
- ReadWriteOnce
capacity:
storage: 1Gi
phase: Bound
E il relativo PV:
kubectl get pv pvc-05247511-096e-4af5-8944-17e0d8222512 -o yaml
apiVersion: v1
kind: PersistentVolume
metadata:
annotations:
pv.kubernetes.io/provisioned-by: rancher.io/local-path
creationTimestamp: "2020-10-16T15:05:23Z"
finalizers:
- kubernetes.io/pv-protection
managedFields:
...
name: pvc-05247511-096e-4af5-8944-17e0d8222512
resourceVersion: "2256"
selfLink: /api/v1/persistentvolumes/pvc-05247511-096e-4af5-8944-17e0d8222512
uid: 3d1e894e-0924-411a-8378-338e48ba4a28
spec:
accessModes:
- ReadWriteOnce
capacity:
storage: 1Gi
claimRef:
apiVersion: v1
kind: PersistentVolumeClaim
name: database-mongo-0
namespace: default
resourceVersion: "2238"
uid: 05247511-096e-4af5-8944-17e0d8222512
hostPath:
path: /var/local-path-provisioner/pvc-05247511-096e-4af5-8944-17e0d8222512_default_database-mongo-0
type: DirectoryOrCreate
nodeAffinity:
required:
nodeSelectorTerms:
- matchExpressions:
- key: kubernetes.io/hostname
operator: In
values:
- kind-worker2
persistentVolumeReclaimPolicy: Delete
storageClassName: standard
volumeMode: Filesystem
status:
phase: Bound
