通过卷在容器间共享数据
emptyDir：当pod删除时卷也被删除，用于存放临时数据
pod实例fortune.yaml
apiVersion: v1
kind: Pod
metadata:
name: fortune
spec:
containers:
- image: luksa/fortune
name: html-generator
volumeMounts:
- name: html
mountPath: /var/htdocs
- image: nginx:alpine
name: web-server
volumeMounts:
- name: html
mountPath: /usr/share/nginx/html
readOnly: true
ports:
- containerPort: 80
protocol: TCP
volumes:
- name: html
emptyDir: {}
kubectl create -f fortune.yaml
kubectl logs fortune html-generator
kubectl logs fortune web-server
kubectl exec -it fortune -c web-server /bin/sh
hostPath：指向节点文件系统的特定目录
[root@mes2 k8study]# kubectl get pods --namespace kube-system
[root@mes2 k8study]# kubectl describe pods kube-addon-manager-minikube --namespace kube-system
Name: kube-addon-manager-minikube
Namespace: kube-system
Priority: 0
Node: minikube/172.27.14.222
Start Time: Fri, 23 Aug 2019 05:37:36 -0400
Labels: component=kube-addon-manager
kubernetes.io/minikube-addons=addon-manager
version=v9.0
Annotations: kubernetes.io/config.hash: 5327162914655af67829868f3ab76393
kubernetes.io/config.mirror: 5327162914655af67829868f3ab76393
kubernetes.io/config.seen: 2019-08-23T05:37:15.210580764-04:00
kubernetes.io/config.source: file
Status: Running
IP: 172.27.14.222
Containers:
kube-addon-manager:
Container ID: docker://0069f20fe82b89a890f89b13e6f812dca78d81d83ecec0534dc9aaded79a7fd3
Image: registry.cn-hangzhou.aliyuncs.com/google_containers/kube-addon-manager:v9.0
Image ID: docker-pullable://registry.cn-hangzhou.aliyuncs.com/google_containers/kube-addon-manager@sha256:672794ee3582521eb8bc4f257d0f70c92893f1989f39a200f9c84bcfe1aea7c9
Port:
Host Port:
State: Running
Started: Tue, 17 Mar 2020 23:23:17 -0400
Last State: Terminated
Reason: Error
Exit Code: 137
Started: Fri, 23 Aug 2019 05:37:37 -0400
Finished: Tue, 17 Mar 2020 23:23:11 -0400
Ready: True
Restart Count: 1
Requests:
cpu: 5m
memory: 50Mi
Environment:
KUBECONFIG: /var/lib/minikube/kubeconfig
Mounts:
/etc/kubernetes/ from addons (ro)
/var/lib/minikube/ from kubeconfig (ro)
Conditions:
Type Status
Initialized True
Ready True
ContainersReady True
PodScheduled True
Volumes:
addons:
Type: HostPath (bare host directory volume)
Path: /etc/kubernetes/
HostPathType:
kubeconfig:
Type: HostPath (bare host directory volume)
Path: /var/lib/minikube/
HostPathType:
QoS Class: Burstable
Node-Selectors:
Tolerations: :NoExecute
Events:
使用持久存储
[root@mes2 k8study]# cat mongonhostpath_pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: mongodb
spec:
volumes:
- name: mongodb-data
hostPath:
path: /data/nfs
type: Directory
containers:
- image: mongo
name: mongodb
volumeMounts:
- name: mongodb-data
mountPath: /data/db
ports:
- containerPort: 27017
protocol: TCP
通过底层持久化存储使用其它类型存储nfs卷
[root@mes2 k8study]# cat mongonfs_pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: mongodb
spec:
volumes:
- name: mongodb-data
nfs:
server: 172.27.14.223
path: /root/data
containers:
- image: mongo
name: mongodb
volumeMounts:
- name: mongodb-data
mountPath: /data/db
ports:
- containerPort: 27017
protocol: TCP
持久卷将底层存储与POD解耦
卷---持久卷---持久卷声明---POD卷
集群管理员将存储卷通过KubenetsAPI服务器创建注册持久卷PV
用户将持久卷声明提交KubenetsAPI服务器匹配到持久卷进行绑定PVC
mongodb-pv-nfs.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
name: mongodb-pv
spec:
capacity:
storage: 1Gi
accessModes:
- ReadWriteOnce
- ReadOnlyMany
persistentVolumeReclaimPolicy: Retain
nfs:
server: 172.27.14.223
path: /root/data
[root@mes2 k8study]# kubectl get pv
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
mongodb-pv 1Gi RWO,ROX Retain Bound default/mongodb-pvc 8m45s
创建持久卷声明获取持久卷
mongodb-pvc.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mongodb-pvc
spec:
resources:
requests:
storage: 1Gi
accessModes:
- ReadWriteOnce
storageClassName: ""
[root@mes2 k8study]# kubectl get pvc
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
mongodb-pvc Bound mongodb-pv 1Gi RWO,ROX 49s
在POD使用持久声明
[root@mes2 k8study]# cat mongopv_pod.yaml
apiVersion: v1
kind: Pod
metadata:
name: mongodb
spec:
volumes:
- name: mongodb-data
persistentVolumeClaim:
claimName: mongodb-pvc
containers:
- image: mongo
name: mongodb
volumeMounts:
- name: mongodb-data
mountPath: /data/db
ports:
- containerPort: 27017
protocol: TCP
手动回收持久卷：将persistentVolumeReclaimPolicy设置为Retain
自动回收持久卷：recycle删除卷内容并再次用于卷声明，delete删除底层存储
持久卷的动态配置storageclass
storageclass-fast-gcepd.yaml
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
name: fast
provisioner: kubernetes.io/gce-pd
parameters:
type: pd-ssd
zone: europe-west1-b
请求特定存储类的PVC定义
mongodb-pvc-pd.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mongodb-pvc
spec:
storageClassName: fast
resources:
requests:
storage: 100Mi
accessModes:
- ReadWriteOnce
创建不指定存储类型的持久卷声明
mongodb-pvc-pd-nostorageclass.yaml
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
name: mongodb-pvc2
spec:
resources:
requests:
storage: 100Mi
accessModes:
- ReadWriteOnce
检查存储类
[root@mes2 ~]# kubectl get sc
NAME PROVISIONER AGE
standard (default) k8s.io/minikube-hostpath 242d
[root@mes2 ~]# kubectl get sc standard -o yaml
apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
annotations:
storageclass.kubernetes.io/is-default-class: "true"
creationTimestamp: "2019-08-23T09:37:55Z"
labels:
addonmanager.kubernetes.io/mode: EnsureExists
name: standard
resourceVersion: "358"
selfLink: /apis/storage.k8s.io/v1/storageclasses/standard
uid: 9d6be323-c93d-44f4-bc05-c068cf0897de
provisioner: k8s.io/minikube-hostpath
reclaimPolicy: Delete
volumeBindingMode: Immediate
参考：
https://www.cnblogs.com/ipyanthony/p/12697883.html
https://www.cnblogs.com/ipyanthony/p/12698748.html
http://www.voidcn.com/article/p-bqeltirs-bqk.html