How to sync a folder in kubernetes statefulset-CodePudding

We are trying to create a solution where we want to replicate changes made to a folder inside any of the pods of the Statefulset. Any file changes inside that folder on any POD should also reflect in other pods. Is there a sidecar solution for this requirement? Because we know that Statefulset will create separate PVs for each POD and there won't be any common mount across the pods of the Statefulset.

CodePudding user response：

You can try using the NFS or file system like EFS using that you will be able to implement the ReadWritemany.

For ref Azure File.

apiVersion: apps/v1beta1
kind: StatefulSet
metadata:
  name: statefulset-azurefile
  labels:
    k8s-app: nginx
    version: v1
spec:
  serviceName: statefulset-azurefile
  replicas: 1
  template:
    metadata:
      labels:
        k8s-app: nginx
        version: v1
    spec:
      containers:
      - name: statefulset-azurefile
        image: nginx
        volumeMounts:
        - name: persistent-storage
          mountPath: /mnt/azurefile
  volumeClaimTemplates:
  - metadata:
      name: persistent-storage
      annotations:
        volume.beta.kubernetes.io/storage-class: azurefile
    spec:
      accessModes: [ "ReadWriteMany" ]
      resources:
        requests:
          storage: 5Gi

Demo : https://github.com/andyzhangx/demo/tree/master/linux/statefulset

If volumeClaimTemplates not work as expected use the persistentVolumeClaim

Article to read about ReadWriteMany access Mode :https://docs.microsoft.com/en-us/azure/aks/azure-files-volume

If you are on other cloud providers like GCP, AWS, Oracle(OCI) provides different file services.

GCP- Filestore
AWS- EFS
OCI- Filestorage

OCI article if you want to explore : https://enabling-cloud.github.io/oci-learning/manual/StaticPersistentVolumeOnOCI.html