Volume:
Kubernetes中的Volume提供了在容器中挂载外部存储的能力
Pod需要设置卷来源（spec.volume）和挂载点（spec.containers.volumeMounts）两个信息后才可以使用相应的Volume
官方参考地址：https://kubernetes.io/docs/concepts/storage/volumes/
1、emptyDir
创建一个空卷，挂载到Pod中的容器。Pod删除该卷也会被删除。
应用场景：Pod中容器之间数据共享
[root@master01 volume]# cat emptyDir.yaml apiVersion: v1 kind: Pod metadata: name: my-pod spec: # imagePullSecrets: # - name: registry-pull-secret containers: - name: write #一个写容器 image: 10.192.27.111/library/busybox:1.28.4 command: ["sh","-c","for i in {1..100};do echo $i >> /data/hello;sleep 1;done"] volumeMounts: - name: data #使用数据卷 名字与下面一致 mountPath: /data - name: read #一个读容器 image: 10.192.27.111/library/centos:7 command: ["bash","-c","tail -f /data/hello"] volumeMounts: - name: data #使用数据卷 名字与下面一致 mountPath: /data volumes: - name: data #新建一个数据卷 emptyDir: {} [root@master01 volume]#
2、hostPath
挂载Node文件系统上文件或者目录到Pod中的容器。
应用场景：Pod中容器需要访问宿主机文件
[root@master01 volume]# cat hostpath.yaml apiVersion: v1 kind: Pod metadata: name: my-pod spec: containers: - name: busybox image: 10.192.27.111/library/busybox:1.28.4 args: - /bin/sh - -c - sleep 36000 volumeMounts: - name: data mountPath: /data volumes: - name: data hostPath: path: /tmp type: Directory [root@master01 volume]# [root@master01 volume]# kubectl apply -f hostpath.yaml [root@master01 volume]# kubectl get pods NAME READY STATUS RESTARTS AGE my-pod 1/1 Running 0 10s [root@master01 volume]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES my-pod 1/1 Running 0 2m19s 172.17.43.2 10.192.27.115 <none> <none> #查看挂载在哪个节点 [root@master01 volume]# kubectl exec -it my-pod sh #pod里面的 / # ls /data/ systemd-private-16f6a1d6621b4a6d96d2c21f44c6bff3-chronyd.service-6Evm1r / # [root@node01 ~]# ls /tmp/ #node01 10.192.27.115上面的 两者一样 systemd-private-16f6a1d6621b4a6d96d2c21f44c6bff3-chronyd.service-6Evm1r [root@node01 ~]#
3、nfs
#各个node节点安装NFS [root@node01 cfg]# yum -y install nfs-utils [root@node02 cfg]# yum -y install nfs-utils [root@master01 volume]# cat nfs.yaml apiVersion: apps/v1beta1 kind: Deployment metadata: name: nginx-deployment spec: replicas: 3 selector: matchLabels: app: nginx template: metadata: labels: app: nginx spec: containers: - name: nginx image: 10.192.27.111/library/nginx:latest volumeMounts: - name: wwwroot #使用数据卷 mountPath: /usr/share/nginx/html ports: - containerPort: 80 volumes: - name: wwwroot #数据卷 nfs: server: 10.192.27.113 path: /home/kdzd [root@master01 volume]# [root@master01 volume]# kubectl apply -f nfs.yaml deployment.apps/nginx-deployment created [root@master01 volume]# kubectl get pod NAME READY STATUS RESTARTS AGE nginx-deployment-5dfc75bdc4-5wjmj 1/1 Running 0 16s nginx-deployment-5dfc75bdc4-q5mrz 1/1 Running 0 16s nginx-deployment-5dfc75bdc4-qkmxk 1/1 Running 0 16s [root@master01 volume]# kubectl get ep NAME ENDPOINTS AGE kubernetes 10.192.27.100:6443,10.192.27.114:6443 18d [root@master01 volume]# kubectl get pod -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES nginx-deployment-5dfc75bdc4-5wjmj 1/1 Running 0 2m23s 172.17.43.3 10.192.27.115 <none> <none> nginx-deployment-5dfc75bdc4-q5mrz 1/1 Running 0 2m23s 172.17.43.2 10.192.27.115 <none> <none> nginx-deployment-5dfc75bdc4-qkmxk 1/1 Running 0 2m23s 172.17.46.4 10.192.27.116 <none> <none> #测试一下 [root@nfs-server ~]# cd /home/kdzd/ [root@nfs-server kdzd]# vim index.html [root@nfs-server kdzd]# cat index.html #10.192.27.113 <h1>hello world!</h1> [root@nfs-server kdzd]# [root@node02 cfg]# curl 172.17.43.2 <h1>hello world!</h1> [root@node02 cfg]# curl 172.17.43.3 <h1>hello world!</h1> [root@node02 cfg]# curl 172.17.46.4 <h1>hello world!</h1>
PersistentVolume
PersistenVolume（PV）：对存储资源创建和使用的抽象，使得存储作为集群中的资源管理
静态
动态
PersistentVolumeClaim（PVC）：让用户不需要关心具体的Volume实现细节
1、静态
手动创建pv
[root@master01 storage]# cat pv.yaml #麻烦 手动创建pv
apiVersion: v1
kind: PersistentVolume
metadata:
name: my-pv
spec:
capacity:
storage: 5Gi
accessModes:
- ReadWriteMany
nfs:
path: /home/kdzd/data #该目录要存在
server: 10.192.27.113
[root@master01 storage]#
[root@master01 storage]# cat pod-pvc.yaml apiVersion: v1 kind: Pod metadata: name: my-pod spec: containers: - name: nginx image: 10.192.27.111/library/nginx:latest ports: - containerPort: 80 volumeMounts: - name: www mountPath: /usr/share/nginx/html volumes: - name: www persistentVolumeClaim: claimName: my-pvc --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: my-pvc spec: accessModes: - ReadWriteMany resources: requests: storage: 5Gi [root@master01 storage]# [root@master01 storage]# kubectl delete -f pod-pvc.yaml pod "my-pod" deleted persistentvolumeclaim "my-pvc" deleted [root@master01 storage]# kubectl delete -f pv.yaml 注意 已使用过pv要删除掉 persistentvolume "my-pv" deleted [root@master01 storage]# vim pod-pvc.yaml [root@master01 storage]# kubectl apply -f pv.yaml persistentvolume/my-pv created [root@master01 storage]# kubectl get pv NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE my-pv 5Gi RWX Retain Available 10s [root@master01 storage]# kubectl apply -f pod-pvc.yaml pod/my-pod created persistentvolumeclaim/my-pvc created [root@master01 storage]# kubectl get pv,pvc #pv 和 pvc是通过容量和访问模式匹配 NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE persistentvolume/my-pv 5Gi RWX Retain Bound default/my-pvc 58s NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE persistentvolumeclaim/my-pvc Bound my-pv 5Gi RWX 6s [root@master01 storage]# kubectl get pods NAME READY STATUS RESTARTS AGE my-pod 1/1 Running 0 14s [root@master01 storage]# kubectl exec -it my-pod bash root@my-pod:/# ls /usr/share/nginx/html index.html root@my-pod:/# exit exit [root@master01 storage]# kubectl get pods -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES my-pod 1/1 Running 0 3m16s 172.17.43.2 10.192.27.115 <none> <none> [root@master01 storage]# node节点上操作 [root@node01 ~]# curl 172.17.43.2 <h1>hello world!</h1> [root@node01 ~]#
Kubernetes支持持久卷的存储插件：https://kubernetes.io/docs/concepts/storage/persistent-volumes/
2、PersistentVolume 动态供给
Dynamic Provisioning机制工作的核心在于StorageClass的API对象。
StorageClass声明存储插件，用于自动创建PV。
https://github.com/kubernetes-incubator/external-storage/tree/master/nfs-client/deploy 部署的yaml文件
[root@master01 storage-class]# ls
deployment-nfs.yaml nginx-demo.yaml rbac.yaml storageclass-nfs.yaml
[root@master01 storage-class]# kubectl apply -f storageclass-nfs.yaml
storageclass.storage.k8s.io/managed-nfs-storage created
[root@master01 storage-class]# cat storageclass-nfs.yaml
apiVersion: storage.k8s.io/v1beta1
kind: StorageClass
metadata:
name: managed-nfs-storage
provisioner: fuseim.pri/ifs
[root@master01 storage-class]#
[root@master01 storage-class]# kubectl get StorageClass
NAME PROVISIONER AGE
managed-nfs-storage fuseim.pri/ifs 30s
[root@master01 storage-class]#
[root@master01 storage-class]# kubectl apply -f rbac.yaml
serviceaccount/nfs-client-provisioner created
clusterrole.rbac.authorization.k8s.io/nfs-client-provisioner-runner created
clusterrolebinding.rbac.authorization.k8s.io/run-nfs-client-provisioner created
[root@master01 storage-class]# cat rbac.yaml
apiVersion: v1
kind: ServiceAccount
metadata:
name: nfs-client-provisioner
---
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: nfs-client-provisioner-runner
rules:
- apiGroups: [""]
resources: ["persistentvolumes"]
verbs: ["get", "list", "watch", "create", "delete"]
- apiGroups: [""]
resources: ["persistentvolumeclaims"]
verbs: ["get", "list", "watch", "update"]
- apiGroups: ["storage.k8s.io"]
resources: ["storageclasses"]
verbs: ["get", "list", "watch"]
- apiGroups: [""]
resources: ["events"]
verbs: ["list", "watch", "create", "update", "patch"]
---
kind: ClusterRoleBinding
apiVersion: rbac.authorization.k8s.io/v1beta1
metadata:
name: run-nfs-client-provisioner
subjects:
- kind: ServiceAccount
name: nfs-client-provisioner
namespace: default
roleRef:
kind: ClusterRole
name: nfs-client-provisioner-runner
apiGroup: rbac.authorization.k8s.io
[root@master01 storage-class]#
[root@master01 storage-class]# cat deployment-nfs.yaml
apiVersion: apps/v1beta1
kind: Deployment
metadata:
name: nfs-client-provisioner
spec:
replicas: 1
strategy:
type: Recreate
template:
metadata:
labels:
app: nfs-client-provisioner
spec:
# imagePullSecrets:
# - name: registry-pull-secret
serviceAccount: nfs-client-provisioner
containers:
- name: nfs-client-provisioner
image: 10.192.27.111/lizhenliang/nfs-client-provisioner:v2.0.0
volumeMounts:
- name: nfs-client-root
mountPath: /persistentvolumes
env:
- name: PROVISIONER_NAME
value: fuseim.pri/ifs
- name: NFS_SERVER
value: 10.192.27.113
- name: NFS_PATH
value: /home/kdzd/data
volumes:
- name: nfs-client-root
nfs:
server: 10.192.27.113
path: /home/kdzd/data
[root@master01 storage-class]# kubectl get sc
NAME PROVISIONER AGE
managed-nfs-storage fuseim.pri/ifs 2m5s
[root@master01 storage-class]# kubectl apply -f deployment-nfs.yaml
deployment.apps/nfs-client-provisioner created
[root@master01 storage-class]# kubectl get pods
NAME READY STATUS RESTARTS AGE
nfs-client-provisioner-86684d5b5f-8k7x6 1/1 Running 0 6s
[root@master01 storage-class]#
nginx-demo例子：https://kubernetes.io/docs/tutorials/stateful-application/basic-stateful-set/
[root@master01 storage-class]# cat nginx-demo.yaml
apiVersion: v1
kind: Service
metadata:
name: nginx
labels:
app: nginx
spec:
ports:
- port: 80
name: web
clusterIP: None
selector:
app: nginx
---
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: web
spec:
selector:
matchLabels:
app: nginx
serviceName: "nginx"
replicas: 3
template:
metadata:
labels:
app: nginx
spec:
terminationGracePeriodSeconds: 10
containers:
- name: nginx
image: 10.192.27.111/library/nginx:latest
ports:
- containerPort: 80
name: web
volumeMounts:
- name: www
mountPath: /usr/share/nginx/html
volumeClaimTemplates:
- metadata:
name: www
spec:
accessModes: [ "ReadWriteOnce" ]
storageClassName: "managed-nfs-storage"
resources:
requests:
storage: 1Gi
[root@master01 storage-class]#
[root@master01 storage-class]# kubectl apply -f nginx-demo.yaml service/nginx created statefulset.apps/web created [root@master01 storage-class]# kubectl get all NAME READY STATUS RESTARTS AGE pod/nfs-client-provisioner-86684d5b5f-8k7x6 1/1 Running 0 7m51s pod/web-0 1/1 Running 0 71s pod/web-1 1/1 Running 0 19s pod/web-2 1/1 Running 0 17s NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE service/kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 20d service/nginx ClusterIP None <none> 80/TCP 71s NAME READY UP-TO-DATE AVAILABLE AGE deployment.apps/nfs-client-provisioner 1/1 1 1 7m51s NAME DESIRED CURRENT READY AGE replicaset.apps/nfs-client-provisioner-86684d5b5f 1 1 1 7m51s NAME READY AGE statefulset.apps/web 3/3 71s [root@master01 storage-class]# kubectl get pv,pvc NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE persistentvolume/default-www-web-0-pvc-91fdee77-14a9-11ea-9860-1866dafb2f54 1Gi RWO Delete Bound default/www-web-0 managed-nfs-storage 37s persistentvolume/default-www-web-1-pvc-5d362b59-14aa-11ea-9860-1866dafb2f54 1Gi RWO Delete Bound default/www-web-1 managed-nfs-storage 36s persistentvolume/default-www-web-2-pvc-5e5e826e-14aa-11ea-9860-1866dafb2f54 1Gi RWO Delete Bound default/www-web-2 managed-nfs-storage 34s NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE persistentvolumeclaim/www-web-0 Bound default-www-web-0-pvc-91fdee77-14a9-11ea-9860-1866dafb2f54 1Gi RWO managed-nfs-storage 6m17s persistentvolumeclaim/www-web-1 Bound default-www-web-1-pvc-5d362b59-14aa-11ea-9860-1866dafb2f54 1Gi RWO managed-nfs-storage 36s persistentvolumeclaim/www-web-2 Bound default-www-web-2-pvc-5e5e826e-14aa-11ea-9860-1866dafb2f54 1Gi RWO managed-nfs-storage 34s [root@master01 storage-class]# [root@master01 storage-class]# kubectl get svc NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE kubernetes ClusterIP 10.0.0.1 <none> 443/TCP 20d nginx ClusterIP None <none> 80/TCP 4m52s [root@master01 storage-class]# kubectl get pods -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES nfs-client-provisioner-86684d5b5f-8k7x6 1/1 Running 0 11m 172.17.43.2 10.192.27.115 <none> <none> web-0 1/1 Running 0 5m1s 172.17.43.3 10.192.27.115 <none> <none> web-1 1/1 Running 0 4m9s 172.17.46.4 10.192.27.116 <none> <none> web-2 1/1 Running 0 4m7s 172.17.43.4 10.192.27.115 <none> <none> [root@master01 storage-class]#
测试一下： [root@nfs-server kdzd]# ls data/ default-www-web-0-pvc-91fdee77-14a9-11ea-9860-1866dafb2f54 default-www-web-1-pvc-5d362b59-14aa-11ea-9860-1866dafb2f54 default-www-web-2-pvc-5e5e826e-14aa-11ea-9860-1866dafb2f54 [root@nfs-server kdzd]# ls data/default-www-web-0-pvc-91fdee77-14a9-11ea-9860-1866dafb2f54/ [root@nfs-server kdzd]# cp index.html data/default-www-web-0-pvc-91fdee77-14a9-11ea-9860-1866dafb2f54/ [root@nfs-server kdzd]# cp index.html data/default-www-web-1-pvc-5d362b59-14aa-11ea-9860-1866dafb2f54/ [root@nfs-server kdzd]# cp index.html data/default-www-web-2-pvc-5e5e826e-14aa-11ea-9860-1866dafb2f54/ [root@nfs-server kdzd]# [root@node01 ~]# curl 172.17.43.3 <h1>hello world!</h1> [root@node01 ~]#
Kubernetes支持动态供给的存储插件： https://kubernetes.io/docs/concepts/storage/storage-classes/
[root@master01 storage]# cat pod-pvc.yaml apiVersion: v1 kind: Pod metadata: name: my-pod spec: containers: - name: nginx image: 10.192.27.111/library/nginx:latest ports: - containerPort: 80 volumeMounts: - name: www mountPath: /usr/share/nginx/html volumes: - name: www persistentVolumeClaim: claimName: my-pvc --- apiVersion: v1 kind: PersistentVolumeClaim metadata: name: my-pvc spec: accessModes: - ReadWriteMany storageClassName: managed-nfs-storage resources: requests: storage: 5Gi [root@master01 storage]# [root@master01 storage]# vim pod-pvc.yaml [root@master01 storage]# kubectl apply -f pod-pvc.yaml pod/my-pod created persistentvolumeclaim/my-pvc created [root@master01 storage]# kubectl get pods -o wide NAME READY STATUS RESTARTS AGE IP NODE NOMINATED NODE READINESS GATES my-pod 1/1 Running 0 5s 172.17.43.5 10.192.27.115 <none> <none> nfs-client-provisioner-86684d5b5f-8k7x6 1/1 Running 0 15m 172.17.43.2 10.192.27.115 <none> <none> web-0 1/1 Running 0 9m15s 172.17.43.3 10.192.27.115 <none> <none> web-1 1/1 Running 0 8m23s 172.17.46.4 10.192.27.116 <none> <none> web-2 1/1 Running 0 8m21s 172.17.43.4 10.192.27.115 <none> <none> [root@master01 storage]# kubectl get pv,pvc NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE persistentvolume/default-my-pvc-pvc-85a2e9bf-14ab-11ea-9860-1866dafb2f54 5Gi RWX Delete Bound default/my-pvc managed-nfs-storage 14s persistentvolume/default-www-web-0-pvc-91fdee77-14a9-11ea-9860-1866dafb2f54 1Gi RWO Delete Bound default/www-web-0 managed-nfs-storage 8m33s persistentvolume/default-www-web-1-pvc-5d362b59-14aa-11ea-9860-1866dafb2f54 1Gi RWO Delete Bound default/www-web-1 managed-nfs-storage 8m32s persistentvolume/default-www-web-2-pvc-5e5e826e-14aa-11ea-9860-1866dafb2f54 1Gi RWO Delete Bound default/www-web-2 managed-nfs-storage 8m30s NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE persistentvolumeclaim/my-pvc Bound default-my-pvc-pvc-85a2e9bf-14ab-11ea-9860-1866dafb2f54 5Gi RWX managed-nfs-storage 14s persistentvolumeclaim/www-web-0 Bound default-www-web-0-pvc-91fdee77-14a9-11ea-9860-1866dafb2f54 1Gi RWO managed-nfs-storage 14m persistentvolumeclaim/www-web-1 Bound default-www-web-1-pvc-5d362b59-14aa-11ea-9860-1866dafb2f54 1Gi RWO managed-nfs-storage 8m32s persistentvolumeclaim/www-web-2 Bound default-www-web-2-pvc-5e5e826e-14aa-11ea-9860-1866dafb2f54 1Gi RWO managed-nfs-storage 8m30s [root@master01 storage]#