1、pv 简单介绍
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 PV分为静态和动态，动态能够自动创建PV • PersistentVolumeClaim（PVC）：让用户不需要关心具体的Volume实现细节 容器与PV、PVC之间的关系，可以如下图所示： 总的来说，PV是提供者，PVC是消费者，消费的过程就是绑定。 参考网址：1、https://www.cnblogs.com/weifeng1463/p/10037803.html 2、https://blog.csdn.net/qq_25611295/article/details/86065053
2、nfs 搭建：
yum install nfs-utils vim /etc/exports /data/k8s/ 172.16.1.0/24(sync,rw,no_root_squash) systemctl start nfs; systemctl start rpcbind systemctl enable nfs 测试： yum install nfs-utils showmount -e 172.16.1.131
3、PersistentVolume 静态绑定 （手工创建PV、PVC）
[root@VM_0_48_centos prometheus]# cat mypv.yaml
apiVersion: v1
kind: PersistentVolume
metadata:
name: pv001
spec:
capacity:
storage: 10Gi
accessModes:
- ReadWriteMany
nfs:
path: /data/k8s
server: 172.19.0.14
[root@VM_0_48_centos prometheus]# cat mypvc.yaml ###会根据大小和类型自动匹配到上面的PV
kind: PersistentVolumeClaim
apiVersion: v1
metadata:
namespace: kube-system
name: prometheus-claim
spec:
accessModes:
- ReadWriteMany
resources:
requests:
storage: 10Gi
[root@VM_0_48_centos prometheus]# kubectl get pv,pvc -n kube-system
NAME CAPACITY ACCESS MODES RECLAIM POLICY STATUS CLAIM STORAGECLASS REASON AGE
persistentvolume/pv001 10Gi RWX Retain Bound kube-system/prometheus-claim 17m
NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE
persistentvolumeclaim/prometheus-claim Bound pv001 10Gi RWX
4、PersistentVolume 静态PVC使用案例
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: prometheus
namespace: kube-system
labels:
k8s-app: prometheus
kubernetes.io/cluster-service: "true"
addonmanager.kubernetes.io/mode: Reconcile
version: v2.2.1
spec:
serviceName: "prometheus"
replicas: 1
podManagementPolicy: "Parallel"
updateStrategy:
type: "RollingUpdate"
selector:
matchLabels:
k8s-app: prometheus
template:
metadata:
labels:
k8s-app: prometheus
annotations:
scheduler.alpha.kubernetes.io/critical-pod: ''
spec:
priorityClassName: system-cluster-critical
serviceAccountName: prometheus
initContainers:
- name: "init-chown-data"
image: "busybox:latest"
imagePullPolicy: "IfNotPresent"
command: ["chown", "-R", "65534:65534", "/data"]
volumeMounts:
- name: prometheus-data
mountPath: /data
subPath: ""
containers:
- name: prometheus-server-configmap-reload
image: "jimmidyson/configmap-reload:v0.1"
imagePullPolicy: "IfNotPresent"
args:
- --volume-dir=/etc/config
- --webhook-url=http://localhost:9090/-/reload
volumeMounts:
- name: config-volume
mountPath: /etc/config
readOnly: true
resources:
limits:
cpu: 10m
memory: 10Mi
requests:
cpu: 10m
memory: 10Mi
- name: prometheus-server
image: "prom/prometheus:v2.2.1"
imagePullPolicy: "IfNotPresent"
args:
- --config.file=/etc/config/prometheus.yml
- --storage.tsdb.path=/data
- --web.console.libraries=/etc/prometheus/console_libraries
- --web.console.templates=/etc/prometheus/consoles
- --web.enable-lifecycle
ports:
- containerPort: 9090
readinessProbe:
httpGet:
path: /-/ready
port: 9090
initialDelaySeconds: 30
timeoutSeconds: 30
livenessProbe:
httpGet:
path: /-/healthy
port: 9090
initialDelaySeconds: 30
timeoutSeconds: 30
# based on 10 running nodes with 30 pods each
resources:
limits:
cpu: 200m
memory: 1000Mi
requests:
cpu: 200m
memory: 1000Mi
volumeMounts:
- name: config-volume
mountPath: /etc/config
- name: prometheus-data
mountPath: /data
subPath: ""
terminationGracePeriodSeconds: 300
volumes:
- name: config-volume
configMap:
name: prometheus-config
- name: prometheus-data
persistentVolumeClaim: #申明使用静态PVC永久化存储
claimName: prometheus-claim
5、动态PV，K8S调用资源对象自动创建PV。生产环境常用
当我们k8s业务上来的时候，大量的pvc,此时我们人工创建匹配的话，工作量就会非常大了，需要动态的自动挂载相应的存储。
我们需要使用到StorageClass，来对接存储，靠他来自动关联pvc,并创建pv。 Kubernetes支持动态供给的存储插件： https://kubernetes.io/docs/concepts/storage/storage-classes/ 因为NFS不支持动态存储，所以我们需要借用这个存储插件。 nfs动态相关部署可以参考： https://github.com/kubernetes-incubator/external-storage/tree/master/nfs-client/deploy
6、存储对象申明和授权。
定义一个storage
[root@VM_0_48_centos prometheus]# cat storageclass-nfs.yaml
apiVersion: storage.k8s.io/v1beta1
kind: StorageClass
metadata:
name: managed-nfs-storage
provisioner: fuseim.pri/ifs
因为storage自动创建pv需要经过kube-apiserver,所以要进行授权
[root@VM_0_48_centos prometheus]# cat storageclass-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
部署一个自动创建pv的服务
[root@VM_0_48_centos prometheus]# cat prometheus-statefulset.yaml
apiVersion: apps/v1
kind: StatefulSet
metadata:
name: prometheus
namespace: kube-system
labels:
k8s-app: prometheus
kubernetes.io/cluster-service: "true"
addonmanager.kubernetes.io/mode: Reconcile
version: v2.2.1
spec:
serviceName: "prometheus"
replicas: 1
podManagementPolicy: "Parallel"
updateStrategy:
type: "RollingUpdate"
selector:
matchLabels:
k8s-app: prometheus
template:
metadata:
labels:
k8s-app: prometheus
annotations:
scheduler.alpha.kubernetes.io/critical-pod: ''
spec:
priorityClassName: system-cluster-critical
serviceAccountName: prometheus
initContainers:
- name: "init-chown-data"
image: "busybox:latest"
imagePullPolicy: "IfNotPresent"
command: ["chown", "-R", "65534:65534", "/data"]
volumeMounts:
- name: prometheus-data
mountPath: /data
subPath: ""
containers:
- name: prometheus-server-configmap-reload
image: "jimmidyson/configmap-reload:v0.1"
imagePullPolicy: "IfNotPresent"
args:
- --volume-dir=/etc/config
- --webhook-url=http://localhost:9090/-/reload
volumeMounts:
- name: config-volume
mountPath: /etc/config
readOnly: true
resources:
limits:
cpu: 10m
memory: 10Mi
requests:
cpu: 10m
memory: 10Mi
- name: prometheus-server
image: "prom/prometheus:v2.2.1"
imagePullPolicy: "IfNotPresent"
args:
- --config.file=/etc/config/prometheus.yml
- --storage.tsdb.path=/data
- --web.console.libraries=/etc/prometheus/console_libraries
- --web.console.templates=/etc/prometheus/consoles
- --web.enable-lifecycle
ports:
- containerPort: 9090
readinessProbe:
httpGet:
path: /-/ready
port: 9090
initialDelaySeconds: 30
timeoutSeconds: 30
livenessProbe:
httpGet:
path: /-/healthy
port: 9090
initialDelaySeconds: 30
timeoutSeconds: 30
# based on 10 running nodes with 30 pods each
resources:
limits:
cpu: 200m
memory: 1000Mi
requests:
cpu: 200m
memory: 1000Mi
volumeMounts:
- name: config-volume
mountPath: /etc/config
- name: prometheus-data
mountPath: /data
subPath: ""
terminationGracePeriodSeconds: 300
volumes:
- name: config-volume
configMap:
name: prometheus-config
- name: prometheus-data
persistentVolumeClaim:
claimName: prometheus-claim
7、效果测试
[root@VM_0_48_centos prometheus]# cat test.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:
serviceName: "nginx"
replicas: 3
selector:
matchLabels:
app: nginx
template:
metadata:
labels:
app: nginx
spec:
containers:
- name: nginx
image: nginx
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
kubectl exec -it web-0 sh
# cd /usr/share/nginx/html
# touch 1.txt