在K8s中创建本地存储PV

2019/10/9 by Qin Zhiqiang in 云原生 K8s, 本地存储

在本地演练K8s，我们不一定需要分布式存储，只需一个本地存储就可以满足我们的需求。但是，本地存储不能自动分配持久化卷(PV)，需要我们先创建好PV，PVC才能获取到资源。

1. 创建一个本地存储类

# local-storage.yaml
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: local-storage
  annotations:
    storageclass.kubernetes.io/is-default-class: "true"
provisioner: kubernetes.io/no-provisioner
volumeBindingMode: WaitForFirstConsumer

kubectl apply -f local-storage.yaml

其中的storageclass.kubernetes.io/is-default-class: "true"表示该类为默认存储类型。在实际环境中，我们一般都给PVC指定存储类型，避免数据存储到哪都难找。

2. 创建PV

sudo mkdir /mnt/logging-es-data-0

# es-local-pv.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
  name: logging-es-data-0
  labels:
    type: logging-es-data
spec:
  capacity:
    storage: 5Gi
  # volumeMode field requires BlockVolume Alpha feature gate to be enabled.
  volumeMode: Filesystem
  accessModes:
    - ReadWriteOnce
  persistentVolumeReclaimPolicy: Delete
  storageClassName: local-storage
  local:
    path: /mnt/logging-es-data-0
  nodeAffinity:
    required:
      nodeSelectorTerms:
      - matchExpressions:
        - key: kubernetes.io/hostname
          operator: In
          values:
          - k8s-single

kubectl apply -f es-local-pv.yaml

3. PVC中使用PV

如下为 StatefulSets 中的PVC模板。

volumeClaimTemplate:
  accessModes: [ "ReadWriteOnce" ]
  storageClassName: "local-storage"
  selector:
    matchLabels:
      type: "logging-es-data"
  resources:
    requests:
      storage: 2Gi

PVC会通过selector去选择满足资源要求的PV。