rook使用cephfs

2020-02-17

前提

默认安装好了kubernetes集群
默认已经安装好了rook,安装rook参考上篇rook安装及使用ceph rbd
注意: k8s out tree存储有两种方式csi及flexvolume，此文件使用flexvolume，不过csi才是未来。

创建文件系统

编排文件如下filesystem.yaml,其中failureDomain为host且replicated是3时，则osd至少在3个主机上，即ceph至少需要三个存储主机。

kind: CephFilesystem
metadata:
  name: myfs
  namespace: rook-ceph
spec:
  # The metadata pool spec. Must use replication.
  metadataPool:
    replicated:
      size: 3
  # The list of data pool specs. Can use replication or erasure coding.
  dataPools:
    - failureDomain: host
      replicated:
        size: 3
  # The metadata service (mds) configuration
  metadataServer:
    # The number of active MDS instances
    activeCount: 1
    # Whether each active MDS instance will have an active standby with a warm metadata cache for faster failover.
    # If false, standbys will be available, but will not have a warm cache.
    activeStandby: true
    # The affinity rules to apply to the mds deployment
    placement:
    #  nodeAffinity:
    #    requiredDuringSchedulingIgnoredDuringExecution:
    #      nodeSelectorTerms:
    #      - matchExpressions:
    #        - key: role
    #          operator: In
    #          values:
    #          - mds-node
    #  tolerations:
    #  - key: mds-node
    #    operator: Exists
    #  podAffinity:
    #  podAntiAffinity:
    # A key/value list of annotations
    annotations:
    #  key: value
    resources:
    # The requests and limits set here, allow the filesystem MDS Pod(s) to use half of one CPU core and 1 gigabyte of memory
    #  limits:
    #    cpu: "500m"
    #    memory: "1024Mi"
    #  requests:
    #    cpu: "500m"
    #    memory: "1024Mi"

1	kubectl apply -f filesystem.yaml

deployment直接使用

此deployment中的pod共享文件目录，即/var/lib/registry在三个pod中是都可以读写的。编排文件registry.yaml如下

apiVersion: apps/v1
kind: Deployment
metadata:
  name: kube-registry
  namespace: kube-system
  labels:
    k8s-app: kube-registry
    kubernetes.io/cluster-service: "true"
spec:
  replicas: 3
  selector:
    matchLabels:
      k8s-app: kube-registry
  template:
    metadata:
      labels:
        k8s-app: kube-registry
        kubernetes.io/cluster-service: "true"
    spec:
      containers:
      - name: registry
        image: registry:2
        imagePullPolicy: Always
        resources:
          limits:
            cpu: 100m
            memory: 100Mi
        env:
        # Configuration reference: https://docs.docker.com/registry/configuration/
        - name: REGISTRY_HTTP_ADDR
          value: :5000
        - name: REGISTRY_HTTP_SECRET
          value: "Ple4seCh4ngeThisN0tAVerySecretV4lue"
        - name: REGISTRY_STORAGE_FILESYSTEM_ROOTDIRECTORY
          value: /var/lib/registry
        volumeMounts:
        - name: image-store
          mountPath: /var/lib/registry
        ports:
        - containerPort: 5000
          name: registry
          protocol: TCP
        livenessProbe:
          httpGet:
            path: /
            port: registry
        readinessProbe:
          httpGet:
            path: /
            port: registry
      volumes:
      - name: image-store
        flexVolume:
          driver: ceph.rook.io/rook
          fsType: ceph
          options:
            fsName: myfs # name of the filesystem specified in the filesystem CRD.
            clusterNamespace: rook-ceph # namespace where the Rook cluster is deployed
            # by default the path is /, but you can override and mount a specific path of the filesystem by using the path attribute
            # the path must exist on the filesystem, otherwise mounting the filesystem at that path will fail
            #path: /some/path/inside/cephfs

1	kubectl apply -f registry.yaml

通过pv及pvc使用

创建pv

pv编排文件如下pv.yaml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: cephfs-pv1
spec:
  capacity:
    storage: 5Gi
  storageClassName: cephfs
  accessModes:
  - ReadWriteMany
  flexVolume:
    driver: ceph.rook.io/rook
    fsType: ceph
    options:
      clusterNamespace: rook-ceph
      fsName: myfs
      path: /some/bigdata/flex

1	kubectl apply -f pv.yaml

创建pvc

pvc编排文件如下pvc.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: pvc-nas
spec:
  accessModes:
    - ReadWriteMany
  storageClassName: cephfs
  resources:
    requests:
      storage: 5Gi

1	kubectl apply -f pvc.yaml

创建deployment

deployment编排文件如下registry2.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  labels:
    k8s-app: kube-registry
    kubernetes.io/cluster-service: "true"
  name: kube-registry
spec:
  selector:
    matchLabels:
      k8s-app: kube-registry
  strategy:
    rollingUpdate:
      maxSurge: 25%
      maxUnavailable: 25%
    type: RollingUpdate
  template:
    metadata:
      creationTimestamp: null
      labels:
        k8s-app: kube-registry
        kubernetes.io/cluster-service: "true"
    spec:
      containers:
      - env:
        - name: REGISTRY_HTTP_ADDR
          value: :5000
        - name: REGISTRY_HTTP_SECRET
          value: Ple4seCh4ngeThisN0tAVerySecretV4lue
        - name: REGISTRY_STORAGE_FILESYSTEM_ROOTDIRECTORY
          value: /var/lib/registry
        image: registry:2
        imagePullPolicy: Always
        livenessProbe:
          failureThreshold: 3
          httpGet:
            path: /
            port: registry
            scheme: HTTP
          periodSeconds: 10
          successThreshold: 1
          timeoutSeconds: 1
        name: registry
        ports:
        - containerPort: 5000
          name: registry
          protocol: TCP
        readinessProbe:
          failureThreshold: 3
          httpGet:
            path: /
            port: registry
            scheme: HTTP
          periodSeconds: 10
          successThreshold: 1
          timeoutSeconds: 1
        resources:
          limits:
            cpu: 100m
            memory: 100Mi
        terminationMessagePath: /dev/termination-log
        terminationMessagePolicy: File
        volumeMounts:
        - mountPath: /var/lib/registry
          name: image-store
      dnsPolicy: ClusterFirst
      restartPolicy: Always
      schedulerName: default-scheduler
      securityContext: {}
      terminationGracePeriodSeconds: 30
      volumes:
      - name: image-store
        persistentVolumeClaim:
          claimName: pvc-nas

1	kubectl apply -f registry2.yaml

注意：虽然pv和pvc写了大小，但是在此文件系统中可用大于此值，无法做限制。