k8s 挂载ceph rbd

如果集群是用kubeadm安装的必须要安装rbd-provisioner，因为默认以docker 运行的kube-controller-manager容器内没有ceph命令，无法正常工作,关于介绍 https://github.com/kubernetes-retired/external-storage

apiVersion: apps/v1
kind: Deployment
metadata:
  name: rbd-provisioner
  namespace: kube-system
spec:
  replicas: 1
  selector:
    matchLabels:
      app: rbd-provisioner
  strategy:
    type: Recreate
  template:
    metadata:
      labels:
        app: rbd-provisioner
    spec:
      containers:
      - name: rbd-provisioner
        image: "quay.io/external_storage/rbd-provisioner:latest"
        env:
        - name: PROVISIONER_NAME
          value: ceph.com/rbd
      serviceAccountName: persistent-volume-binder

将以上manifest应用到集群

apiVersion: v1
kind: Namespace
metadata:
  name: ceph
---
apiVersion: v1
kind: Secret
metadata:
  name: ceph-storageclass-secret
  namespace: ceph
data:
  key: QVFCZ3pjNWh1RHVOT2hBQWVDa2xxTWtlQ3g2bGtJdU5uNFpWOVE9PQ==  #ceph auth get-key client.admin | base64(获取ceph 客户端的秘钥，k8s需要用这个key去ceph授权创建rbd)
type:
  kubernetes.io/rbd
---
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: ceph
  namespace: ceph
  annotations:
    storageclass.kubernetes.io/is-default-class: "true" #设置为默认StorageClass,这样创建pvc时就不用指定StorageClass
provisioner: ceph.com/rbd
parameters:
  monitors: 192.168.3.80
  adminId: admin
  adminSecretName: ceph-storageclass-secret
  adminSecretNamespace: ceph
  pool: k8s
  userId: admin
  userSecretName: ceph-storageclass-secret
  userSecretNamespace: ceph
  imageFormat: "2"
  imageFeatures: "layering"

将以上manifest应用到集群

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: ceph-pvc-test2
  namespace: default
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 100Gi

kubectl get pvc 查看自动创建的pvc

 坑：

当第一次安装 rbd-provisioner后这时候如果直接去创建一个pvc,会一直出于pending，且报错：ormal  ExternalProvisioning  3s (x5 over 37s)  persistentvolume-controller  waiting for a volume to be created, either by external provisioner "ceph.com/rbd" or manually created by system administrator，这时候网上有教程去修改k8s api增加参数：--feature-gates=RemoveSelfLink=false（改完重启），然并卵，后面发现除了加参数还必须将pvc定义后马上pod 去引用刚才的pvc，这样才会创建成功，原因未知。必须以下这样写

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: ceph-pvc-test2
  namespace: default
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 100Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:
 name: test
spec:
 selector:
  matchLabels:
    app: test
 replicas: 1
 template:
  metadata:
   labels:
    app: test
  spec:
   containers:
   - name: test
     image: reg.xthklocal.cn/xthk-library/basic-config-center-bms:1.1.0.2
     ports:
     - containerPort: 80
       name: http
       protocol: TCP
     volumeMounts:
       - name: mysql-data
         mountPath: /var/lib/mysql
   volumes:
    - name: mysql-data
      persistentVolumeClaim:
        claimName: ceph-pvc-test2

再次查看pvc状态:

 发现已经调度成功了，然后我们再次尝试只创建一个pvc

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: ceph-pvc-test4
  namespace: default
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 100Gi

 查看状态

 既然成功了，那就不要再动他了吧