Topology Aware
对于云盘这种存储卷类型，只能在相同zone的ecs上进行挂载，在多可用区的集群环境中，就需要对pv、pvc和pod进行一致性zone调度；
1. 传统使用方式：
通过PV、PVC所在zoneid信息，把pod调度到相应zone；
即在PV中定义相应的zoneid信息，当一个pod使用这个pv的时候，scheduler会根据pv的zoneid把pod调度到相应可用区；
具体配置：
apiVersion: v1
kind: PersistentVolume
metadata:
labels:
failure-domain.beta.kubernetes.io/region: cn-beijing
failure-domain.beta.kubernetes.io/zone: cn-beijing-e
name: d-2ze6wbcvihjeaw5bae0c
spec:
accessModes:
- ReadWriteOnce
capacity:
storage: 20Gi
csi:
driver: diskplugin.csi.alibabacloud.com
volumeHandle: d-bp1fqy1enb2rtymx5g5y
persistentVolumeReclaimPolicy: Delete
storageClassName: alicloud-disk-ssd通过在PV中添加下面label来完成调度：
labels:
failure-domain.beta.kubernetes.io/region: cn-beijing
failure-domain.beta.kubernetes.io/zone: cn-beijing-e2. 通过Topology Aware方式
上述方式需要先确定云盘的可用区，然后与pod进行关联调度。
而Topology Aware方式是云盘根据pod所在的zone进行创建。
使用下面storageclass，WaitForFirstConsumer配置会使pv controller在pod启动的时候去创建pv，并通过pod所在的zone信息来确定pv所在的zone。
kind: StorageClass
apiVersion: storage.k8s.io/v1beta1
metadata:
name: alicloud-disk-aware
provisioner: diskplugin.csi.alibabacloud.com
volumeBindingMode: WaitForFirstConsumer
parameters:
type: cloud_ssd环境准备
集群创建、依赖配置、CSI插件部署等请参考：CSI部署详解
创建StorageClass
WaitForFirstConsumer：表示只有pod消费这个pvc的时候才驱动Provisioner进行pv创建；
kind: StorageClass
apiVersion: storage.k8s.io/v1beta1
metadata:
name: alicloud-disk-aware
provisioner: diskplugin.csi.alibabacloud.com
volumeBindingMode: WaitForFirstConsumer
parameters:
type: cloud_ssd创建动态PVC PV
通过下面模板创建动态卷PV:
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: disk-pvc
spec:
accessModes:
- ReadWriteOnce
resources:
requests:
storage: 25Gi
storageClassName: alicloud-disk-aware# kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
disk-pvc Pending alicloud-disk-aware 23m创建应用
apiVersion: apps/v1
kind: Deployment
metadata:
name: nginx-disk
labels:
app: nginx
spec:
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx:1.7.9
ports:
- containerPort: 80
volumeMounts:
- name: disk-pvc
mountPath: "/data"
volumes:
- name: disk-pvc
persistentVolumeClaim:
claimName: disk-pvc验证挂载、高可用
查看pvc已经绑定完成
# kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
disk-pvc Bound pvc-bf7732a6-a7cf-11e9-8dec-00163e0a6ecc 25Gi RWO alicloud-disk-aware 18s
# kubectl get pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
pvc-bf7732a6-a7cf-11e9-8dec-00163e0a6ecc 25Gi RWO Delete Bound default/disk-pvc alicloud-disk-aware 7s
查看pvc详情，volume.kubernetes.io/selected-node即为pv的调度信息：
# kubectl describe pvc disk-pvc
Name: disk-pvc
Namespace: default
StorageClass: alicloud-disk-aware
Status: Bound
Volume: pvc-bf7732a6-a7cf-11e9-8dec-00163e0a6ecc
Labels: <none>
Annotations: pv.kubernetes.io/bind-completed: yes
pv.kubernetes.io/bound-by-controller: yes
volume.beta.kubernetes.io/storage-provisioner: diskplugin.csi.alibabacloud.com
volume.kubernetes.io/selected-node: cn-hangzhou.192.168.6.149
Finalizers: [kubernetes.io/pvc-protection]
Capacity: 25Gi
Access Modes: RWO
VolumeMode: Filesystem
查看pod，验证云盘挂载成功，创建测试文件；
# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx-disk-6d5659d745-2ts26 1/1 Running 0 2m1s
# kubectl exec nginx-disk-6d5659d745-2ts26 ls /data
lost+found
# kubectl exec nginx-disk-6d5659d745-2ts26 touch /data/test
# kubectl exec nginx-disk-6d5659d745-2ts26 ls /data
lost+found
test
删除Pod，查看重建Pod是否数据稳定；
# kubectl delete pod nginx-disk-6d5659d745-2ts26
pod "nginx-disk-6d5659d745-2ts26" deleted
# kubectl get pod
NAME READY STATUS RESTARTS AGE
nginx-disk-6d5659d745-m5z9p 1/1 Running 0 11s
# kubectl exec nginx-disk-6d5659d745-m5z9p ls /data
lost+found
test