Is it possible to mount different pods to the same portion of a local persistent volume?

Question

Basically, I\'m creating a StatefulSet deployment with 2 pods (single host cluster), I would like to that each pod will be able to mount to a base folder in the host, and to

Answer 1

I am able to achieve the above scenario, what you need is "claimRef" in your pv to bind your PVC. Please have a look at following pv json and statefulset json

PV-0.json

{
  "kind": "PersistentVolume",
  "apiVersion": "v1",
  "metadata": {
    "name": "pv-data-vol-0",
    "labels": {
      "type": "local"
    }
  },
  "spec": {
    "capacity": {
      "storage": "10Gi"
    },
    "accessModes": [
      "ReadWriteOnce"
    ],
    "storageClassName": "local-storage",
    "local": {
      "path": "/prafull/data/pv-0"
    },
    "claimRef": {
      "namespace": "default",
      "name": "data-test-sf-0"
    },
    "nodeAffinity": {
      "required": {
        "nodeSelectorTerms": [
          {
            "matchExpressions": [
              {
                "key": "kubernetes.io/hostname",
                "operator": "In",
                "values": [
                  "ip-10-0-1-46.ec2.internal"
                ]
              }
            ]
          }
        ]
      }
    }
  }
}

PV-1.json

{
  "kind": "PersistentVolume",
  "apiVersion": "v1",
  "metadata": {
    "name": "pv-data-vol-1",
    "labels": {
      "type": "local"
    }
  },
  "spec": {
    "capacity": {
      "storage": "10Gi"
    },
    "accessModes": [
      "ReadWriteOnce"
    ],
    "storageClassName": "local-storage",
    "local": {
      "path": "/prafull/data/pv-1"
    },
    "claimRef": {
      "namespace": "default",
      "name": "data-test-sf-1"
    },
    "nodeAffinity": {
      "required": {
        "nodeSelectorTerms": [
          {
            "matchExpressions": [
              {
                "key": "kubernetes.io/hostname",
                "operator": "In",
                "values": [
                  "ip-10-0-1-46.ec2.internal"
                ]
              }
            ]
          }
        ]
      }
    }
  }
}

Statefulset.json

{
  "kind": "StatefulSet",
  "apiVersion": "apps/v1beta1",
  "metadata": {
    "name": "test-sf",
    "labels": {
      "state": "test-sf"
    }
  },
  "spec": {
    "replicas": 2,
    "template": {
      "metadata": {
        "labels": {
          "app": "test-sf"
        },
        "annotations": {
          "pod.alpha.kubernetes.io/initialized": "true"
        }
      }
      ...
      ...
    },
    "volumeClaimTemplates": [
      {
        "metadata": {
          "name": "data"
        },
        "spec": {
          "accessModes": [
            "ReadWriteOnce"
          ],
          "storageClassName": "local-storage",
          "resources": {
            "requests": {
              "storage": "10Gi"
            }
          }
        }
      }
    ]
  }
}

There will be two pods created test-sf-0 and test-sf-1 which in-turn will be created two PVC data-test-sf-0 and data-test-sf-1 which will be bound to PV-0 and Pv-1 respectively. Hence test-sf-0 will write to the location specified in PV-0 and test-sf-1 will write in location specified on PV-1. Hope this helps.