20201222 kubernetes (四)

課堂資料

配置 Pod 以使用 PersistentVolume 作为存储Kubernetes

RHEL / CentOS 7 安裝 NFS Server - Linux 技術手札Linux 技術手札

ConfigMap · 从 Docker 到 Kubernetes 进阶手册

NFS

nfs 網路存儲、pod重啟後數據依在

• 第一步：

  • install nfs-server

  • 設置掛載路徑

  • 掛載路徑需要創建出來

• 第二步：在其他 node 也安裝 nfs

• 第三步：啟動nfs-server

• 第四步：在 k8s 集群部署應用使用 nfs 以持久網路儲存

課堂練習

NFS

vm1

安裝 NFS Server

yum install nfs-utils

設定分享目錄

mkdir -p /var/nfsshare

chmod -R 777 /var/nfsshare/

開啟 /etc/exports 檔案

vim /etc/exports

/data/ 192.168.8.0/24(rw,sync,no_root_squash,no_all_squash)
/var/nfsshare/ 192.168.8.0/24(rw,sync,no_root_squash,no_all_squash)

啟動 NFS Server, 設定開機自動執行及在 firewalld 開放 NFS

systemctl restart rpcbind

systemctl restart nfs-server

systemctl status rpcbind

systemctl status nfs-server

cd /var/nfsshare/

ls

touch 1 2 3

ls

cd

gedit pv.yaml pvc.yaml

pv.yaml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: my-pv
spec:
  capacity:
    storage: 5Gi
  accessModes:
    - ReadWriteMany
  nfs:
    path: /var/nfsshare/
    server: 192.168.8.129

pvc.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: httpd-dep2
spec:
  selector:
    matchLabels:
      app: httpd
  replicas: 1
  template:
    metadata:
      labels:
        app: httpd
    spec:
      containers:
      - name: httpd
        image: httpd:2.4.46
        ports:
        - containerPort: 80
        volumeMounts:
        - name: wwwroot
          mountPath: /usr/local/apache2/htdocs
        ports:
        - containerPort: 80
      volumes:
        - name: wwwroot
          persistentVolumeClaim:
            claimName: my-pvc

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 5Gi

ls /var/nfsshare/

kubectl apply -f pv.yaml

kubectl get pv

cd /var/nfsshare/

ls

echo "hi" > hi.htm

cd

ls

kubectl apply -f pvc.yaml

kubectl get pods -o wide

kubectl get deployment

kubectl delete deployment httpd

kubectl get deployment

kubectl get pod -o wide

kubectl get deployment

kubectl describe deployment httpd-dep2

kubectl get pvc

kubectl get deployment

kubectl get deployment

kubectl get svc

kubectl delete svc httpd

kubectl delete svc httpd2

kubectl get svc

kubectl get pod

kubectl delete pod --all

kubectl get pod

kubectl describe deployment httpd-dep2

kubectl get pod -o wide

ls

kubectl get pvc

kubectl get deployment

kubectl describe deployment httpd-dep2

kubectl get pod

gedit pvc.yaml

pvc.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: httpd-dep2
spec:
  selector:
    matchLabels:
      app: httpd
  replicas: 1
  template:
    metadata:
      labels:
        app: httpd
    spec:
      containers:
      - name: httpd
        image: httpd:2.4.46
        ports:
        - containerPort: 80
#        volumeMounts:
#        - name: wwwroot
#          mountPath: /usr/local/apache2/htdocs
#        ports:
#        - containerPort: 80
#      volumes:
#        - name: wwwroot
#          persistentVolumeClaim:
#            claimName: my-pvc

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 5Gi

kubectl apply -f pvc.yaml

kubectl get deployment

kubectl get pod

kubectl get pod -o wide

curl [podID]

gedit pvc.yaml

pvc.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: httpd-dep2
spec:
  selector:
    matchLabels:
      app: httpd
  replicas: 1
  template:
    metadata:
      labels:
        app: httpd
    spec:
      containers:
      - name: httpd
        image: httpd:2.4.46
        ports:
        - containerPort: 80
#        volumeMounts:
#        - name: wwwroot
#          mountPath: /usr/local/apache2/htdocs
#        ports:
#        - containerPort: 80
      volumes:
        - name: wwwroot
          persistentVolumeClaim:
            claimName: my-pvc

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 5Gi

kubectl apply -f pvc.yaml

kubectl get deployment

kubectl get pod -o wide

curl [podID]

gedit pvc.yaml

pvc.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: httpd-dep2
spec:
  selector:
    matchLabels:
      app: httpd
  replicas: 1
  template:
    metadata:
      labels:
        app: httpd
    spec:
      containers:
      - name: httpd
        image: httpd:2.4.46
        ports:
        - containerPort: 80
#        volumeMounts:
#        - name: wwwroot
#          mountPath: /usr/local/apache2/htdocs
        ports:
        - containerPort: 80
      volumes:
        - name: wwwroot
          persistentVolumeClaim:
            claimName: my-pvc

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 5Gi

kubectl apply -f pvc.yaml

kubectl get deployment

kubectl get pod -o wide

curl [podID]

kubectl get pod

kubectl exec [podName] -it -- bash

cd htdocs/

ls

pwd

exit

kubectl get svc

gedit pvc.yaml

pvc.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: httpd-dep2
spec:
  selector:
    matchLabels:
      app: httpd
  replicas: 1
  template:
    metadata:
      labels:
        app: httpd
    spec:
      containers:
      - name: httpd
        image: httpd:2.4.46
        ports:
        - containerPort: 80
        volumeMounts:
        - name: wwwroot
          mountPath: /usr/local/apache2/htdocs
        ports:
        - containerPort: 80
      volumes:
        - name: wwwroot
          persistentVolumeClaim:
            claimName: my-pvc

---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 5Gi

kubectl apply -f pvc.yaml

kubectl get deployment

kubectl get pod

kubectl get pods

kubectl describe deployment httpd-dep2

cd ..

ls

cd

mkdir pv

cd pv

gedit 1.yaml 2.yaml 3.yaml &

1.yaml

apiVersion: v1
kind: PersistentVolume
metadata:
  name: my-pv
spec:
  capacity:
    storage: 5Gi
  accessModes:
    - ReadWriteMany
  persistentVolumeReclaimPolicy: Recycle
  storageClassName: test
  nfs:
    path: /var/nfsshare
    server: 192.168.8.129

2.yaml

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: my-pvc
spec:
  accessModes:
    - ReadWriteMany
  resources:
    requests:
      storage: 1Gi
  storageClassName: test 

3.yaml

apiVersion: v1
kind: Pod
metadata:
  name: task-pv-pod
spec:
  volumes:
    - name: task-pv-storage
      persistentVolumeClaim:
        claimName: my-pvc
  containers:
    - name: task-pv-container
      image: httpd:2.4.46
      ports:
        - containerPort: 80
          name: "http-server"
      volumeMounts:
        - mountPath: "/usr/local/apache2/htdocs"
          name: task-pv-storage

kubectl apply -f 1.yaml

kubectl get pv

kubectl apply -f 2.yaml

kubectl get pvc

kubectl apply -f 3.yaml

kubectl get pod

kubectl get pod -o wide

cd /var/nfsshare/

ls

curl [podID]/hi.htm

echo "abc" > abc.htm

curl [podID]/abc.htm

ls

kubectl get pod

kubectl delete pod task-pv-pod

kubectl get pod

cd

cd pv

kubectl apply -f 3.yaml

kubectl get pod

kubectl get pod -o wide

curl [podID]/hi.htm

curl [podID]/abc.htm

vm2

安裝 NFSClient

yum install nfs-utils

建立 NFS 目錄掛載點

mkdir -p /mnt/nfs/var/nfsshare

mount 指令掛載 192.168.8.129分享出來的目錄

mount -t nfs 192.168.8.129:/var/nfsshare /mnt/nfs/var/nfsshare/

cd /mnt/nfs/var/nfsshare/

touch a b cd

ls

ls

cd

umount /mnt/nfs/var/nfsshare/

ls /mnt/nfs/var/nfsshare/

docker images

vm3

安裝 NFSClient

yum install nfs-utils

建立 NFS 目錄掛載點

mkdir -p /mnt/nfs/var/nfsshare

mount 指令掛載 192.168.8.129分享出來的目錄

mount -t nfs 192.168.8.129:/var/nfsshare /mnt/nfs/var/nfsshare/

cd /mnt/nfs/var/nfsshare/

ls

cd

umount /mnt/nfs/var/nfsshare/

ls /mnt/nfs/var/nfsshare/

ConfigMap

vm1

cd

mkdir /cm

cd cm

gedit myconfigmap.yaml

kind: ConfigMap
apiVersion: v1
metadata:
  name: cm-demo
  namespace: default
data:
  data.1: hello
  data.2: world
  config: |
    property.1=value-1
    property.2=value-2
    property.3=value-3

cd testcm

gedit mysql.conf redis.conf

mysql.conf

host=127.0.0.1
port=3306

redis.conf

host=127.0.0.1
port=6379

cat mysql.conf

cat redis.conf

cd ..

kubectl create configmap cm-demo1 --from-file=testcm

kubectl get cm

kubectl describe cm cm-demo1

kubectl create configmap cm-demo3 --from-literal=db.host=localhost --from-literal=db.port=3306

kubectl get cm

kubectl describe cm cm-demo3

gedit testpod.yaml

apiVersion: v1
kind: Pod
metadata:
  name: testcm1-pod
spec:
  containers:
    - name: testcm
      image: busybox
      command: [ "/bin/sh", "-c", "env" ]
      env:
        - name: DB_HOST
          valueFrom:
            configMapKeyRef:
              name: cm-demo3
              key: db.host
        - name: DB_PORT
          valueFrom:
            configMapKeyRef:
              name: cm-demo3
              key: db.port
      envFrom:
        - configMapRef:
            name: cm-demo1

kubectl apply -f testpod.yaml

kubectl get pod

kubectl delete pod --all

gedit testpod.yaml

apiVersion: v1
kind: Pod
metadata:
  name: testcm2-pod
spec:
  containers:
    - name: testcm2
      image: busybox
      command: [ "/bin/sh", "-c", "echo $(DB_HOST) $(DB_PORT)" ]
      env:
        - name: DB_HOST
          valueFrom:
            configMapKeyRef:
              name: cm-demo3
              key: db.host
        - name: DB_PORT
          valueFrom:
            configMapKeyRef:
              name: cm-demo3
              key: db.port

kubectl apply -f testpod.yaml

kubectl get pod

kubectl logs testcm2-pod