1、K8s為什么要使用存儲？
答：k8s中的副本控制器保證了pod的始終存儲，卻保證不了Pod中的數據。只有啟動一個新pod的，之前pod中的數據會隨着容器的刪掉而丟失。k8s中的rc啟動指定數量的Pod，當某個Pod死掉了，會在新的節點啟動新的Pod，k8s中想要實現數據持久化，需要使用一個叫做共享存儲的，讓Pod里面的數據掛載到這個共享存儲上面，就算在新的節點啟動新的Pod，依然可以保證數據不丟失。
2、k8s中的PV和PVC的概念。
答：PersistentVolume(簡稱為PV，持久化存儲)，由管理員添加的一個存儲的描述，是一個全局資源，沒有namespace的限制，包含存儲的類型，存儲的大小和訪問模式等等。它的生命周期獨立於Pod，例如，當使用它的Pod銷毀時對PV沒有影響。PV創建的時候，需要聲明可以提供多大的存儲能力，而PVC創建的時候要設置需求多大的硬盤。
PersistentVolumeClaim(簡稱為PVC)，是Namespace里面的資源，描述對PV的一個請求。請求信息包含存儲大小，訪問模式等等。注意，PV和PVC是一一綁定的，Pod使用PV的話，是Pod訪問PVC，而PVC與PV進行一一綁定的。
3、首先這里創建PV使用到的是NFS，這里首先安裝一下NFS，如下所示：
需要Master主節點先安裝NFS服務端，在所有Node節點安裝NFS客戶端，不然Pod無法使用，因為掛載不上，在三台機器都執行下面的命令即可。
1 [root@k8s-master ~]# yum install nfs-utils.x86_64 2 Loaded plugins: fastestmirror, langpacks, product-id, search-disabled-repos, subscription-manager 3 4 This system is not registered with an entitlement server. You can use subscription-manager to register. 5 6 Loading mirror speeds from cached hostfile 7 * base: mirrors.tuna.tsinghua.edu.cn 8 * extras: mirrors.bfsu.edu.cn 9 * updates: mirrors.bfsu.edu.cn 10 base | 3.6 kB 00:00:00 11 extras | 2.9 kB 00:00:00 12 updates | 2.9 kB 00:00:00 13 Resolving Dependencies 14 --> Running transaction check 15 ---> Package nfs-utils.x86_64 1:1.3.0-0.61.el7 will be updated 16 ---> Package nfs-utils.x86_64 1:1.3.0-0.66.el7 will be an update 17 --> Finished Dependency Resolution 18 19 Dependencies Resolved 20 21 ================================================================================================================================================================================================================= 22 Package Arch Version Repository Size 23 ================================================================================================================================================================================================================= 24 Updating: 25 nfs-utils x86_64 1:1.3.0-0.66.el7 base 412 k 26 27 Transaction Summary 28 ================================================================================================================================================================================================================= 29 Upgrade 1 Package 30 31 Total size: 412 k 32 Is this ok [y/d/N]: y 33 Downloading packages: 34 Running transaction check 35 Running transaction test 36 Transaction test succeeded 37 Running transaction 38 Updating : 1:nfs-utils-1.3.0-0.66.el7.x86_64 1/2 39 Cleanup : 1:nfs-utils-1.3.0-0.61.el7.x86_64 2/2 40 Verifying : 1:nfs-utils-1.3.0-0.66.el7.x86_64 1/2 41 Verifying : 1:nfs-utils-1.3.0-0.61.el7.x86_64 2/2 42 43 Updated: 44 nfs-utils.x86_64 1:1.3.0-0.66.el7 45 46 Complete! 47 [root@k8s-master ~]#
在三台機器都要安裝nfs-utils的包的，然后在服務器端，開始配置配置文件/etc/exports，如下所示：
1 [root@k8s-master ~]# vim /etc/exports
配置內容，如下所示：
1 # 共享data目錄，允許192.168.110.*訪問，即允許110段ip地址訪問。讀寫權限，同步，不做root用戶、所有用戶的UID映射 2 /data 192.168.110.0/24(rw,async,no_root_squash,no_all_squash)
創建/data/目錄下面的一個目錄，如下所示：
1 [root@k8s-master ~]# cat /etc/exports 2 # 共享data目錄，允許192.168.110.*訪問，即允許110段ip地址訪問。讀寫權限，同步，不做root用戶、所有用戶的UID映射 3 /data 192.168.110.0/24(rw,async,no_root_squash,no_all_squash) 4 5 6 [root@k8s-master ~]# mkdir /data/k8s 7 mkdir: cannot create directory ‘/data/k8s’: No such file or directory 8 [root@k8s-master ~]# mkdir /data/k8s -p 9 [root@k8s-master ~]#
然后重啟nfs、rpcbind，如下所示：
1 [root@k8s-master ~]# systemctl restart rpcbind.service 2 [root@k8s-master ~]# systemctl restart nfs.service 3 [root@k8s-master ~]#
在另外兩個節點查看是否可以查看到nfs，如下所示：
1 [root@k8s-node2 ~]# showmount -e 192.168.110.133 2 Export list for 192.168.110.133: 3 /data 192.168.110.0/24 4 [root@k8s-node2 ~]# 5 6 7 [root@k8s-node3 ~]# showmount -e 192.168.110.133 8 Export list for 192.168.110.133: 9 /data 192.168.110.0/24 10 [root@k8s-node3 ~]#
下面開始創建一個PV，如下所示：
1 [root@k8s-master ~]# cd k8s/ 2 [root@k8s-master k8s]# ls 3 book-master.war dashboard dashboard.zip deploy health heapster hpa metrics namespace pod rc skydns skydns.zip svc tomcat_demo tomcat_demo.zip 4 [root@k8s-master k8s]# mkdir volume 5 [root@k8s-master k8s]# cd volume/ 6 [root@k8s-master volume]# vim test-pv.yaml
配置內容，如下所示：
1 apiVersion: v1 2 kind: PersistentVolume 3 metadata: 4 name: testpv 5 labels: 6 type: testpv 7 spec: 8 capacity: 9 storage: 10Gi 10 accessModes: 11 - ReadWriteMany 12 persistentVolumeReclaimPolicy: Recycle 13 nfs: 14 path: "/data/k8s" 15 server: 192.168.110.133 16 readOnly: false
開始創建這個PV，並進行查看，如下所示：
1 [root@k8s-master volume]# kubectl create -f test-pv.yaml 2 persistentvolume "testpv" created 3 [root@k8s-master volume]# kubectl get pv -o wide 4 NAME CAPACITY ACCESSMODES RECLAIMPOLICY STATUS CLAIM REASON AGE 5 testpv 10Gi RWX Recycle Available 10s 6 [root@k8s-master volume]#
再創建一個5Gi的PV，修改一下配置文件，然后進行創建，名稱必須不一樣，標簽可以一樣的，如下所示：
1 [root@k8s-master volume]# vim test-pv.yaml 2 [root@k8s-master volume]# kubectl create -f test-pv.yaml 3 persistentvolume "testpv2" created 4 [root@k8s-master volume]# kubectl get pv -o wide 5 NAME CAPACITY ACCESSMODES RECLAIMPOLICY STATUS CLAIM REASON AGE 6 testpv 10Gi RWX Recycle Available 3m 7 testpv2 5Gi RWX Recycle Available 3s 8 [root@k8s-master volume]#
開始創建PVC，如下所示：
1 apiVersion: v1 2 kind: PersistentVolumeClaim 3 kind: PersistentVolumeClaim 4 apiVersion: v1 5 metadata: 6 name: nfs 7 spec: 8 accessModes: 9 - ReadWriteMany 10 resources: 11 requests: 12 storage: 1Gi
1 [root@k8s-master volume]# kubectl create -f test-pvc.yaml 2 persistentvolumeclaim "nfs" created 3 [root@k8s-master volume]# kubectl get pvc -o wide 4 NAME STATUS VOLUME CAPACITY ACCESSMODES AGE 5 nfs Bound testpv2 5Gi RWX 9s 6 [root@k8s-master volume]#
此時，可以發現pvc已經綁定到了testpv2這個PV上面了，pvc優先綁定到容量小的pv上面的。自己也可以再創建一個6G的PV，然后再創建一個7G的PVC，可以發現這個PVC會綁定到10G的這個PV上面了的。
4、K8s持久化實戰，自己可以參考一下這篇https://www.cnblogs.com/wangxu01/articles/11411113.html。
這里首先引用一下https://www.cnblogs.com/biehongli/p/13150609.html，使用k8s運行Java Web項目，這里緊接着這個鏈接的操作，創建一個mysql，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl create -f mysql-rc.yml 2 replicationcontroller "mysql" created 3 [root@k8s-master tomcat_demo]# kubectl create -f mysql-svc.yml 4 service "mysql" created 5 [root@k8s-master tomcat_demo]# kubectl get all -o wide 6 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 7 rc/mysql 1 1 1 14s mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 8 9 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 10 svc/kubernetes 10.254.0.1 <none> 443/TCP 24d <none> 11 svc/mysql 10.254.234.52 <none> 3306/TCP 11s app=mysql 12 13 NAME READY STATUS RESTARTS AGE IP NODE 14 po/mysql-4j7qk 1/1 Running 0 14s 172.16.16.3 k8s-node3 15 [root@k8s-master tomcat_demo]#
下面是mysql-rc.yaml的配置文件，如下所示：
1 [root@k8s-master tomcat_demo]# cat mysql-rc.yml 2 apiVersion: v1 3 kind: ReplicationController 4 metadata: 5 name: mysql 6 spec: 7 replicas: 1 8 selector: 9 app: mysql 10 template: 11 metadata: 12 labels: 13 app: mysql 14 spec: 15 containers: 16 - name: mysql 17 image: 192.168.110.133:5000/mysql:5.7.30 18 ports: 19 - containerPort: 3306 20 env: 21 - name: MYSQL_ROOT_PASSWORD 22 value: '123456' 23 [root@k8s-master tomcat_demo]#
下面是mysql-svc.yaml的配置文件，如下所示：
1 [root@k8s-master tomcat_demo]# cat mysql-svc.yml 2 apiVersion: v1 3 kind: Service 4 metadata: 5 name: mysql 6 spec: 7 ports: 8 - port: 3306 9 targetPort: 3306 10 selector: 11 app: mysql 12 [root@k8s-master tomcat_demo]#
下面是tomcat-rc.yml的配置文件，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl get all -o wide 2 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 3 rc/mysql 1 1 1 2h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 4 rc/myweb 1 1 1 11m myweb 192.168.110.133:5000/tomcat-book:latest app=myweb 5 6 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 7 svc/kubernetes 10.254.0.1 <none> 443/TCP 24d <none> 8 svc/mysql 10.254.234.52 <none> 3306/TCP 2h app=mysql 9 svc/myweb 10.254.14.249 <nodes> 8080:30008/TCP 10m app=myweb 10 11 NAME READY STATUS RESTARTS AGE IP NODE 12 po/mysql-4j7qk 1/1 Running 0 2h 172.16.16.3 k8s-node3 13 po/myweb-f2dqn 1/1 Running 0 11m 172.16.16.5 k8s-node3 14 [root@k8s-master tomcat_demo]# vim tomcat-rc.yml 15 [root@k8s-master tomcat_demo]# cat tomcat-rc.yml 16 apiVersion: v1 17 kind: ReplicationController 18 metadata: 19 name: myweb 20 spec: 21 replicas: 1 22 selector: 23 app: myweb 24 template: 25 metadata: 26 labels: 27 app: myweb 28 spec: 29 containers: 30 - name: myweb 31 # image: 192.168.110.133:5000/tomcat:latest 32 image: 192.168.110.133:5000/tomcat-book:latest 33 ports: 34 - containerPort: 8080 35 env: 36 - name: MYSQL_SERVICE_HOST 37 # value: '192.168.110.133' # 如果已經安裝了dns服務，那么這里可以直接使用mysql的svc即Service的名稱mysql 38 value: '10.254.234.52' 39 - name: MYSQL_SERVICE_PORT 40 value: '3306' 41 [root@k8s-master tomcat_demo]#
下面是tomcat-svc.yml的配置文件，如下所示：
1 [root@k8s-master tomcat_demo]# cat tomcat-svc.yml 2 apiVersion: v1 3 kind: Service 4 metadata: 5 name: myweb 6 spec: 7 type: NodePort 8 ports: 9 - port: 8080 10 nodePort: 30008 11 selector: 12 app: myweb 13 [root@k8s-master tomcat_demo]#
然后可以通過Navicat連上這個機器的Mysql，然后創建一個數據庫，將sql執行一下，就完成了Mysql的任務了，下面就是將web項目搞到tomcat里面，然后使用k8s啟動tomcat就行了。
怎么創建java web端的鏡像呢，首先鏡像要運行在tomcat里面的，創建鏡像的第一步，說明繼承自那個基礎鏡像，因為程序是Java web程序，肯定是需要用到tomcat的，先將tomcat的鏡像下載下來。
1 [root@k8s-master tomcat_demo]# vim Dockerfile
配置內容，如下所示：
1 # 第一步，說明繼承那個基礎鏡像，tomcat作為基礎鏡像。此處告訴Docker我要做自己的鏡像，以tomcat鏡像為起點。 2 from docker.io/tomcat:latest3 4 # 第二步，描述鏡像的所有者，可以省略。 5 MAINTAINER biehl biehl@qq.com 6 7 # 第三步，將自己的web應用放到鏡像里面，將本地的war包拷貝到tomcat的webapps目錄下面。可以看看程序是否可以隨着tomcat啟動起來。 8 COPY book-master.war /usr/local/tomcat/webapps
dokcer build命令就是用來執行Dockerfile里面所描述的每一件事情，最終會把docker鏡像給我們構建出來。
1 [root@k8s-master tomcat_demo]# docker build -t tomcat-book:latest . 2 Sending build context to Docker daemon 9.699 MB 3 Step 1/3 : FROM 192.168.110.133:5000/tomcat:latest 4 ---> 2eb5a120304e 5 Step 2/3 : MAINTAINER biehl biehl@qq.com 6 ---> Running in a51d06f7bddb 7 ---> 0be82c0d264e 8 Removing intermediate container a51d06f7bddb 9 Step 3/3 : COPY book-master.war /usr/local/tomcat/webapps 10 ---> 98fbba0fd03c 11 Removing intermediate container e71c8a9f14c9 12 Successfully built 98fbba0fd03c 13 [root@k8s-master tomcat_demo]# docker images 14 REPOSITORY TAG IMAGE ID CREATED SIZE 15 book-master.war latest 98fbba0fd03c 11 seconds ago 657 MB
然后可以將這個上傳到私有倉庫里面，方便其他Node節點下載，如下所示：
1 [root@k8s-master ~]# docker tag tomcat-book:latest 192.168.110.133:5000/tomcat-book:latest 2 [root@k8s-master ~]# docker push 192.168.110.133:5000/tomcat-book:latest
然后創建tomcat的rc、svc，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl create -f tomcat-rc.yml 2 replicationcontroller "myweb" created 3 [root@k8s-master tomcat_demo]# kubectl get all -o wide 4 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 5 rc/mysql 1 1 1 2h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 6 rc/myweb 1 1 1 7s myweb 192.168.110.133:5000/tomcat-book:latest app=myweb 7 8 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 9 svc/kubernetes 10.254.0.1 <none> 443/TCP 24d <none> 10 svc/mysql 10.254.234.52 <none> 3306/TCP 2h app=mysql 11 12 NAME READY STATUS RESTARTS AGE IP NODE 13 po/mysql-4j7qk 1/1 Running 0 2h 172.16.16.3 k8s-node3 14 po/myweb-cvd16 1/1 Running 0 7s 172.16.16.5 k8s-node3 15 [root@k8s-master tomcat_demo]# kubectl describe pod myweb-cvd16 16 Name: myweb-cvd16 17 Namespace: default 18 Node: k8s-node3/192.168.110.135 19 Start Time: Mon, 29 Jun 2020 20:12:54 +0800 20 Labels: app=myweb 21 Status: Running 22 IP: 172.16.16.5 23 Controllers: ReplicationController/myweb 24 Containers: 25 myweb: 26 Container ID: docker://1caf37bb344e394af5701035f9a28631129260f4cb5a5f1f88a214a66891631e 27 Image: 192.168.110.133:5000/tomcat-book:latest 28 Image ID: docker-pullable://192.168.110.133:5000/tomcat-book@sha256:e838afdd7d378bd078dbf431d5f956a197b94caba624b238049108e64cf66526 29 Port: 8080/TCP 30 State: Running 31 Started: Mon, 29 Jun 2020 20:12:55 +0800 32 Ready: True 33 Restart Count: 0 34 Volume Mounts: <none> 35 Environment Variables: 36 MYSQL_SERVICE_HOST: 10.254.234.52 37 MYSQL_SERVICE_PORT: 3306 38 Conditions: 39 Type Status 40 Initialized True 41 Ready True 42 PodScheduled True 43 No volumes. 44 QoS Class: BestEffort 45 Tolerations: <none> 46 Events: 47 FirstSeen LastSeen Count From SubObjectPath Type Reason Message 48 --------- -------- ----- ---- ------------- -------- ------ ------- 49 22s 22s 1 {default-scheduler } Normal Scheduled Successfully assigned myweb-cvd16 to k8s-node3 50 21s 21s 1 {kubelet k8s-node3} spec.containers{myweb} Normal Pulling pulling image "192.168.110.133:5000/tomcat-book:latest" 51 21s 21s 1 {kubelet k8s-node3} spec.containers{myweb} Normal Pulled Successfully pulled image "192.168.110.133:5000/tomcat-book:latest" 52 21s 21s 1 {kubelet k8s-node3} spec.containers{myweb} Normal Created Created container with docker id 1caf37bb344e; Security:[seccomp=unconfined] 53 21s 21s 1 {kubelet k8s-node3} spec.containers{myweb} Normal Started Started container with docker id 1caf37bb344e 54 [root@k8s-master tomcat_demo]# kubectl create -f tomcat-svc.yml 55 service "myweb" created 56 [root@k8s-master tomcat_demo]# kubectl get all -o wide 57 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 58 rc/mysql 1 1 1 2h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 59 rc/myweb 1 1 1 34s myweb 192.168.110.133:5000/tomcat-book:latest app=myweb 60 61 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 62 svc/kubernetes 10.254.0.1 <none> 443/TCP 24d <none> 63 svc/mysql 10.254.234.52 <none> 3306/TCP 2h app=mysql 64 svc/myweb 10.254.132.182 <nodes> 8080:30008/TCP 4s app=myweb 65 66 NAME READY STATUS RESTARTS AGE IP NODE 67 po/mysql-4j7qk 1/1 Running 0 2h 172.16.16.3 k8s-node3 68 po/myweb-cvd16 1/1 Running 0 34s 172.16.16.5 k8s-node3 69 [root@k8s-master tomcat_demo]#
訪問地址http://192.168.110.133:30008/，報錯了，源服務器未能找到目標資源的表示或者是不願公開一個已經存在的資源表示。
還按照之前搞過的，這次找到是那台機器運行了這個Pod，找到了，然后將webapps.dist目錄里面的文件拷貝到webapps里面就可以了。
1 [root@k8s-node3 ~]# docker ps 2 CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 3 1caf37bb344e 192.168.110.133:5000/tomcat-book:latest "catalina.sh run" 6 minutes ago Up 6 minutes k8s_myweb.2d2942f9_myweb-cvd16_default_dc959aad-ba01-11ea-9f79-000c2919d52d_c7802e7f 4 5683c0b919d2 192.168.110.133:5000/pod-infrastructure:latest "/pod" 6 minutes ago Up 6 minutes k8s_POD.37d60359_myweb-cvd16_default_dc959aad-ba01-11ea-9f79-000c2919d52d_919c83e8 5 9b536ac00a54 192.168.110.133:5000/mysql:5.7.30 "docker-entrypoint..." 2 hours ago Up 2 hours k8s_mysql.10e32324_mysql-4j7qk_default_0385e04b-b9ef-11ea-9f79-000c2919d52d_9c9a5b84 6 e4ff14740839 192.168.110.133:5000/pod-infrastructure:latest "/pod" 2 hours ago Up 2 hours k8s_POD.30310355_mysql-4j7qk_default_0385e04b-b9ef-11ea-9f79-000c2919d52d_3a453e5f 7 d2f4e384b94c 192.168.110.133:5000/kubernetes-dashboard-amd64:v1.5.0 "/dashboard --port..." 9 hours ago Up 9 hours k8s_kubernetes-dashboard.4dfe9ff5_kubernetes-dashboard-latest-3333846798-3mm68_kube-system_8a34f648-b8f4-11ea-91a9-000c2919d52d_d5314b66 8 eac876e090b7 192.168.110.133:5000/pod-infrastructure:latest "/pod" 9 hours ago Up 9 hours k8s_POD.3ba4035b_kubernetes-dashboard-latest-3333846798-3mm68_kube-system_8a34f648-b8f4-11ea-91a9-000c2919d52d_c44ca4ec 9 77da48b3cd89 registry "/entrypoint.sh /e..." 11 days ago Up 9 hours 0.0.0.0:5000->5000/tcp registry 10 [root@k8s-node3 ~]# docker exec -it 1caf37bb344e /bin/bash 11 root@myweb-cvd16:/usr/local/tomcat# ls 12 BUILDING.txt CONTRIBUTING.md LICENSE NOTICE README.md RELEASE-NOTES RUNNING.txt bin conf lib logs native-jni-lib temp webapps webapps.dist work 13 root@myweb-cvd16:/usr/local/tomcat# cd webapps 14 root@myweb-cvd16:/usr/local/tomcat/webapps# ls 15 book-master book-master.war 16 root@myweb-cvd16:/usr/local/tomcat/webapps# cd .. 17 root@myweb-cvd16:/usr/local/tomcat# ls 18 BUILDING.txt CONTRIBUTING.md LICENSE NOTICE README.md RELEASE-NOTES RUNNING.txt bin conf lib logs native-jni-lib temp webapps webapps.dist work 19 root@myweb-cvd16:/usr/local/tomcat# cd webapps.dist/ 20 root@myweb-cvd16:/usr/local/tomcat/webapps.dist# ls 21 ROOT docs examples host-manager manager 22 root@myweb-cvd16:/usr/local/tomcat/webapps.dist# cp -r * ../webapps 23 root@myweb-cvd16:/usr/local/tomcat/webapps.dist# ls 24 ROOT docs examples host-manager manager 25 root@myweb-cvd16:/usr/local/tomcat/webapps.dist# cd .. 26 root@myweb-cvd16:/usr/local/tomcat# cd webapps 27 root@myweb-cvd16:/usr/local/tomcat/webapps# ls 28 ROOT book-master book-master.war docs examples host-manager manager 29 root@myweb-cvd16:/usr/local/tomcat/webapps#
訪問地址http://192.168.110.133:30008/，如下所示：
訪問地址http://192.168.110.133:30008/book-master/，如下所示：
需要注意的是，我的項目連接的mysql的地址就是Master節點的ip地址的，然后Pod服務與服務之間的訪問，比如tomcat訪問mysql的是tomcat連的是mysql的svc的地址，如下所示：
1 drivername=com.mysql.jdbc.Driver 2 url=jdbc:mysql://192.168.110.133:3306/book?useUnicode=true&characterEncoding=utf8 3 user=root 4 password=123456
運行項目可以正常運行，簡單的效果，如下所示：
查看kubernetes dashboard的界面如下所示：
點擊可以查看詳細的日志信息，如下所示：
可以通過命令對Pod的副本數進行調整，如下所示：
1 [root@k8s-master ~]# kubectl scale rc myweb --replicas=2 2 replicationcontroller "myweb" scaled 3 [root@k8s-master ~]# kubectl get all -o wide 4 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 5 rc/mysql 1 1 1 3h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 6 rc/myweb 2 2 1 59m myweb 192.168.110.133:5000/tomcat-book:latest app=myweb 7 8 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 9 svc/kubernetes 10.254.0.1 <none> 443/TCP 24d <none> 10 svc/mysql 10.254.234.52 <none> 3306/TCP 3h app=mysql 11 svc/myweb 10.254.132.182 <nodes> 8080:30008/TCP 59m app=myweb 12 13 NAME READY STATUS RESTARTS AGE IP NODE 14 po/mysql-4j7qk 1/1 Running 0 3h 172.16.16.3 k8s-node3 15 po/myweb-cvd16 1/1 Running 0 59m 172.16.16.5 k8s-node3 16 po/myweb-sk8qp 0/1 ContainerCreating 0 2s <none> k8s-node2 17 [root@k8s-master ~]# kubectl get all -o wide 18 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 19 rc/mysql 1 1 1 3h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 20 rc/myweb 2 2 2 1h myweb 192.168.110.133:5000/tomcat-book:latest app=myweb 21 22 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 23 svc/kubernetes 10.254.0.1 <none> 443/TCP 24d <none> 24 svc/mysql 10.254.234.52 <none> 3306/TCP 3h app=mysql 25 svc/myweb 10.254.132.182 <nodes> 8080:30008/TCP 59m app=myweb 26 27 NAME READY STATUS RESTARTS AGE IP NODE 28 po/mysql-4j7qk 1/1 Running 0 3h 172.16.16.3 k8s-node3 29 po/myweb-cvd16 1/1 Running 0 1h 172.16.16.5 k8s-node3 30 po/myweb-sk8qp 1/1 Running 0 59s 172.16.94.5 k8s-node2 31 [root@k8s-master ~]#
創建的時間大概幾十秒吧，我的私有倉庫包含項目的tomcat有七八百兆左右，也可以通過kubernetes dashboard進行查看，如下所示：
后來測試如何保證刪除了mysql的pod如何保證數據不丟失的時候，發現一個問題的，我發現不管我怎么刪除mysql的Pod之后，rc會立馬啟動一個mysql，但是我的數據就是沒有丟失呢，我此時還沒有做PV、PVC呢，后來發現原來我用的是192.168.110.133機器安裝的mysql，也是服氣子了，所以重新改了配置文件，然后重新創建mysql、myweb。下面開始創建mysql，如下所示：
1 [root@k8s-master ~]# cd k8s/ 2 [root@k8s-master k8s]# ls 3 book-master.war dashboard dashboard.zip deploy health heapster hpa metrics namespace pod rc skydns skydns.zip svc tomcat_demo tomcat_demo.zip volume 4 [root@k8s-master k8s]# cd tomcat_demo/ 5 [root@k8s-master tomcat_demo]# ls 6 book-master2.0.war book-master3.0.war book-master.war Dockerfile mysql-rc.yml mysql-svc.yml tomcat-rc.yml tomcat-svc.yml 7 [root@k8s-master tomcat_demo]# kubectl create -f mysql-rc.yml 8 replicationcontroller "mysql" created 9 [root@k8s-master tomcat_demo]# kubectl create -f mysql-svc.yml 10 service "mysql" created 11 [root@k8s-master tomcat_demo]# kubectl get all -o wide 12 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 13 rc/mysql 1 1 1 22s mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 14 15 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 16 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 17 svc/mysql 10.254.133.121 <none> 3306/TCP 17s app=mysql 18 19 NAME READY STATUS RESTARTS AGE IP NODE 20 po/mysql-2jtr6 1/1 Running 0 22s 172.16.16.3 k8s-node3 21 [root@k8s-master tomcat_demo]#
創建完畢Mysql之后，如果通過k8s進入到mysql呢，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl exec -it mysql-2jtr6 bash 2 root@mysql-2jtr6:/# mysql -uroot -p123456 3 mysql: [Warning] Using a password on the command line interface can be insecure. 4 Welcome to the MySQL monitor. Commands end with ; or \g. 5 Your MySQL connection id is 2 6 Server version: 5.7.30 MySQL Community Server (GPL) 7 8 Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved. 9 10 Oracle is a registered trademark of Oracle Corporation and/or its 11 affiliates. Other names may be trademarks of their respective 12 owners. 13 14 Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. 15 16 mysql> show databases; 17 +--------------------+ 18 | Database | 19 +--------------------+ 20 | information_schema | 21 | mysql | 22 | performance_schema | 23 | sys | 24 +--------------------+ 25 4 rows in set (0.00 sec) 26 27 mysql> CREATE database book DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci; 28 Query OK, 1 row affected (0.00 sec) 29 30 mysql>
同樣，也可以通過訪問Pod的ip地址來訪問Mysql服務的，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl get all -o wide 2 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 3 rc/mysql 1 1 1 12h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 4 rc/myweb 1 1 1 11h myweb 192.168.110.133:5000/tomcat-book:4.0 app=myweb 5 6 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 7 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 8 svc/mysql 10.254.133.121 <none> 3306/TCP 12h app=mysql 9 svc/myweb 10.254.45.162 <nodes> 8080:30008/TCP 11h app=myweb 10 11 NAME READY STATUS RESTARTS AGE IP NODE 12 po/mysql-2jtr6 1/1 Running 0 12h 172.16.16.3 k8s-node3 13 po/myweb-9qhk9 1/1 Running 0 11h 172.16.16.5 k8s-node3 14 [root@k8s-master tomcat_demo]# mysql -uroot -p123456 -h172.16.16.3 15 mysql: [Warning] Using a password on the command line interface can be insecure. 16 Welcome to the MySQL monitor. Commands end with ; or \g. 17 Your MySQL connection id is 29 18 Server version: 5.7.30 MySQL Community Server (GPL) 19 20 Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved. 21 22 Oracle is a registered trademark of Oracle Corporation and/or its 23 affiliates. Other names may be trademarks of their respective 24 owners. 25 26 Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. 27 28 mysql>
然后可以創建自己的數據表，由於執行創建數據表的sql過長，這里進行了省略哦，如下所示：
1 mysql> show databases; 2 +--------------------+ 3 | Database | 4 +--------------------+ 5 | information_schema | 6 | book | 7 | mysql | 8 | performance_schema | 9 | sys | 10 +--------------------+ 11 5 rows in set (0.00 sec) 12 13 mysql> use book; 14 Database changed 15 mysql> show tables; 16 Empty set (0.00 sec) 17 18 mysql>
創建好數據表進行查看，如下所示：
1 mysql> show tables; 2 +---------------------+ 3 | Tables_in_book | 4 +---------------------+ 5 | book_info | 6 | book_recommendation | 7 | book_sort | 8 | user_book | 9 | user_info | 10 +---------------------+ 11 5 rows in set (0.00 sec) 12 13 mysql>
然后創建已經將2.x版本的項目打到tomcat的rc、svc，如下所示：
注意：其實這里為了搞清楚java項目的mysql的ip地址、端口號這些填啥，我已經打了很多版本了，最新的是4.0版本的了，操作幾乎一樣，但是注意下面的配置。
1 [root@k8s-master tomcat_demo]# kubectl create -f tomcat-rc.yml 2 replicationcontroller "myweb" created 3 [root@k8s-master tomcat_demo]# kubectl create -f tomcat-svc.yml 4 service "myweb" created 5 [root@k8s-master tomcat_demo]# kubectl get all -o wide 6 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 7 rc/mysql 1 1 1 6m mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 8 rc/myweb 1 1 1 12s myweb 192.168.110.133:5000/tomcat-book:2.0 app=myweb 9 10 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 11 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 12 svc/mysql 10.254.133.121 <none> 3306/TCP 6m app=mysql 13 svc/myweb 10.254.117.144 <nodes> 8080:30008/TCP 8s app=myweb 14 15 NAME READY STATUS RESTARTS AGE IP NODE 16 po/mysql-2jtr6 1/1 Running 0 6m 172.16.16.3 k8s-node3 17 po/myweb-965n1 1/1 Running 0 12s 172.16.16.5 k8s-node3 18 [root@k8s-master tomcat_demo]#
然后開始訪問地址http://192.168.110.133:30008/book-master2.0/，k8s訪問tomcat報錯，源服務器未能找到目標資源的表示或者是不願公開一個已經存在的資源表示。還可以按照上面的方法進行解決，這里再貼下步驟了，如下所示:
1 [root@k8s-node3 ~]# docker ps 2 CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES 3 a242e75ee4fa 192.168.110.133:5000/tomcat-book:2.0 "catalina.sh run" 3 minutes ago Up 3 minutes k8s_myweb.fc01434c_myweb-965n1_default_b63cbb65-ba10-11ea-9f79-000c2919d52d_dec12b6a 4 e67764bb9b4b 192.168.110.133:5000/pod-infrastructure:latest "/pod" 3 minutes ago Up 3 minutes k8s_POD.37d60359_myweb-965n1_default_b63cbb65-ba10-11ea-9f79-000c2919d52d_57e633de 5 3220e5f8475c 192.168.110.133:5000/mysql:5.7.30 "docker-entrypoint..." 10 minutes ago Up 10 minutes k8s_mysql.10e32324_mysql-2jtr6_default_cbcf1d80-ba0f-11ea-9f79-000c2919d52d_99438f65 6 0d4e3411d100 192.168.110.133:5000/pod-infrastructure:latest "/pod" 10 minutes ago Up 10 minutes k8s_POD.30310355_mysql-2jtr6_default_cbcf1d80-ba0f-11ea-9f79-000c2919d52d_9504bf1f 7 d2f4e384b94c 192.168.110.133:5000/kubernetes-dashboard-amd64:v1.5.0 "/dashboard --port..." 11 hours ago Up 11 hours k8s_kubernetes-dashboard.4dfe9ff5_kubernetes-dashboard-latest-3333846798-3mm68_kube-system_8a34f648-b8f4-11ea-91a9-000c2919d52d_d5314b66 8 eac876e090b7 192.168.110.133:5000/pod-infrastructure:latest "/pod" 11 hours ago Up 11 hours k8s_POD.3ba4035b_kubernetes-dashboard-latest-3333846798-3mm68_kube-system_8a34f648-b8f4-11ea-91a9-000c2919d52d_c44ca4ec 9 77da48b3cd89 registry "/entrypoint.sh /e..." 12 days ago Up 11 hours 0.0.0.0:5000->5000/tcp registry 10 [root@k8s-node3 ~]# docker exec -it a242e75ee4fa /bin/bash 11 root@myweb-965n1:/usr/local/tomcat# cd webapps.dist/ 12 root@myweb-965n1:/usr/local/tomcat/webapps.dist# cp -r * ../webapps 13 root@myweb-965n1:/usr/local/tomcat/webapps.dist# ls 14 ROOT docs examples host-manager manager 15 root@myweb-965n1:/usr/local/tomcat/webapps.dist# cd ../webapps 16 root@myweb-965n1:/usr/local/tomcat/webapps#
注意，我這里的java項目使用的就是svc/mysql的ip地址10.254.133.12，然后tomcat-rc.yml由於配置了dns，直接使用的是mysql這個svc的名稱。
1 [root@k8s-master tomcat_demo]# kubectl get all -o wide 2 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 3 rc/mysql 1 1 1 48m mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 4 rc/myweb 1 1 1 5m myweb 192.168.110.133:5000/tomcat-book:4.0 app=myweb 5 6 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 7 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 8 svc/mysql 10.254.133.121 <none> 3306/TCP 48m app=mysql 9 svc/myweb 10.254.45.162 <nodes> 8080:30008/TCP 5m app=myweb 10 11 NAME READY STATUS RESTARTS AGE IP NODE 12 po/mysql-2jtr6 1/1 Running 0 48m 172.16.16.3 k8s-node3 13 po/myweb-9qhk9 1/1 Running 0 5m 172.16.16.5 k8s-node3 14 [root@k8s-master tomcat_demo]#
注意tomcat-rc.yml里面的mysql的ip地址直接使用了mysql的svc名稱，如果沒有配置dns就需要每次修改mysql的svc的ip地址。
1 [root@k8s-master tomcat_demo]# cat tomcat-rc.yml 2 apiVersion: v1 3 kind: ReplicationController 4 metadata: 5 name: myweb 6 spec: 7 replicas: 1 8 selector: 9 app: myweb 10 template: 11 metadata: 12 labels: 13 app: myweb 14 spec: 15 containers: 16 - name: myweb 17 # image: 192.168.110.133:5000/tomcat:latest 18 image: 192.168.110.133:5000/tomcat-book:4.0 19 ports: 20 - containerPort: 8080 21 env: 22 - name: MYSQL_SERVICE_HOST 23 # value: '192.168.110.133' 24 # value: '10.254.234.52' 25 value: 'mysql' 26 - name: MYSQL_SERVICE_PORT 27 value: '3306' 28 [root@k8s-master tomcat_demo]#
我的java項目的連接mysql數據庫的ip地址和端口號直接使用的mysql的svc的ip地址，端口號，這樣的缺點就是每次創建mysql都會隨機分配一個新的ip地址，就很麻煩的。
1 drivername=com.mysql.jdbc.Driver 2 url=jdbc:mysql://10.254.133.121:3306/book?useUnicode=true&characterEncoding=utf8 3 user=root 4 password=123456
如果按照上面的鏈接k8s創建的mysql，如果mysql的svc即service重新建一個，會導致這個java連不上mysql數據庫的，我又使用了下面這個配置連接k8s里面的mysql數據庫，這里使用了svc（service）的名稱來代替，如果配置好了dns的話，是可以這樣配置的，我的tomcat-rc.yml連接k8s創建的mysql就是這樣配置的，如下所示：
1 drivername=com.mysql.jdbc.Driver 2 url=jdbc:mysql://mysql:3306/book?useUnicode=true&characterEncoding=utf8 3 user=root 4 password=123456
此時我的tomcat-rc.yml是這個樣子的。
1 [root@k8s-master tomcat_demo]# cat tomcat-rc.yml 2 apiVersion: v1 3 kind: ReplicationController 4 metadata: 5 name: myweb 6 spec: 7 replicas: 1 8 selector: 9 app: myweb 10 template: 11 metadata: 12 labels: 13 app: myweb 14 spec: 15 containers: 16 - name: myweb 17 # image: 192.168.110.133:5000/tomcat:latest 18 image: 192.168.110.133:5000/tomcat-book:5.0 19 ports: 20 - containerPort: 8080 21 env: 22 - name: MYSQL_SERVICE_HOST 23 # value: '192.168.110.133' 24 # value: '10.254.234.52' 25 value: 'mysql' 26 - name: MYSQL_SERVICE_PORT 27 value: '3306' 28 [root@k8s-master tomcat_demo]#
此時，刪除mysql的pod驗證一下，自己java web如此配置連接k8s里面的Mysql是否正常，然后驗證數據沒有持久化會造成數據丟失嗎？
1 [root@k8s-master tomcat_demo]# kubectl get all -o wide 2 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 3 rc/mysql 1 1 1 12h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 4 rc/myweb 1 1 1 9m myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 5 6 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 7 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 8 svc/mysql 10.254.133.121 <none> 3306/TCP 12h app=mysql 9 svc/myweb 10.254.180.131 <nodes> 8080:30008/TCP 9m app=myweb 10 11 NAME READY STATUS RESTARTS AGE IP NODE 12 po/mysql-2jtr6 1/1 Running 0 12h 172.16.16.3 k8s-node3 13 po/myweb-k23p0 1/1 Running 0 9m 172.16.16.5 k8s-node3 14 [root@k8s-master tomcat_demo]# kubectl delete pod mysql-2jtr6 15 pod "mysql-2jtr6" deleted 16 [root@k8s-master tomcat_demo]# kubectl get all -o wide 17 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 18 rc/mysql 1 1 1 13h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 19 rc/myweb 1 1 1 15m myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 20 21 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 22 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 23 svc/mysql 10.254.133.121 <none> 3306/TCP 13h app=mysql 24 svc/myweb 10.254.180.131 <nodes> 8080:30008/TCP 14m app=myweb 25 26 NAME READY STATUS RESTARTS AGE IP NODE 27 po/mysql-2jtr6 1/1 Terminating 0 13h 172.16.16.3 k8s-node3 28 po/mysql-kt2v2 1/1 Running 0 2s 172.16.16.6 k8s-node3 29 po/myweb-k23p0 1/1 Running 0 15m 172.16.16.5 k8s-node3 30 [root@k8s-master tomcat_demo]#
最終會發現你刪除的那個mysql的pod被刪除之前，新的mysql的pod已經創建成功了的。
1 [root@k8s-master tomcat_demo]# kubectl get all -o wide 2 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 3 rc/mysql 1 1 1 13h mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 4 rc/myweb 1 1 1 16m myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 5 6 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 7 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 8 svc/mysql 10.254.133.121 <none> 3306/TCP 13h app=mysql 9 svc/myweb 10.254.180.131 <nodes> 8080:30008/TCP 15m app=myweb 10 11 NAME READY STATUS RESTARTS AGE IP NODE 12 po/mysql-kt2v2 1/1 Running 0 1m 172.16.16.6 k8s-node3 13 po/myweb-k23p0 1/1 Running 0 16m 172.16.16.5 k8s-node3 14 [root@k8s-master tomcat_demo]#
然后登錄mysql，這里通過mysql的pod的ip地址進行登錄，發現數據已經丟失了，如下所示：
1 [root@k8s-master tomcat_demo]# mysql -uroot -p123456 -h172.16.16.6 2 mysql: [Warning] Using a password on the command line interface can be insecure. 3 Welcome to the MySQL monitor. Commands end with ; or \g. 4 Your MySQL connection id is 4 5 Server version: 5.7.30 MySQL Community Server (GPL) 6 7 Copyright (c) 2000, 2019, Oracle and/or its affiliates. All rights reserved. 8 9 Oracle is a registered trademark of Oracle Corporation and/or its 10 affiliates. Other names may be trademarks of their respective 11 owners. 12 13 Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. 14 15 mysql> show databases; 16 +--------------------+ 17 | Database | 18 +--------------------+ 19 | information_schema | 20 | mysql | 21 | performance_schema | 22 | sys | 23 +--------------------+ 24 4 rows in set (0.01 sec) 25 26 mysql>
或者可以使用k8s的命令進入到Mysql，進行登錄，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl exec -it mysql-kt2v2 bash 2 root@mysql-kt2v2:/# mysql -uroot -p123456 3 mysql: [Warning] Using a password on the command line interface can be insecure. 4 Welcome to the MySQL monitor. Commands end with ; or \g. 5 Your MySQL connection id is 5 6 Server version: 5.7.30 MySQL Community Server (GPL) 7 8 Copyright (c) 2000, 2020, Oracle and/or its affiliates. All rights reserved. 9 10 Oracle is a registered trademark of Oracle Corporation and/or its 11 affiliates. Other names may be trademarks of their respective 12 owners. 13 14 Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. 15 16 mysql> show databases; 17 +--------------------+ 18 | Database | 19 +--------------------+ 20 | information_schema | 21 | mysql | 22 | performance_schema | 23 | sys | 24 +--------------------+ 25 4 rows in set (0.00 sec) 26 27 mysql>
注意：如果Mysql的mysql-svc.yml，這個svc配置了NodePort方式，對外暴漏了端口號，那么在服務器可以通過訪問暴漏的端口號，和服務器的ip地址，已經mysql的賬號，密碼就可以訪問k8s里面創建的mysql了的。總之，訪問方式有很多種，自己理清楚，自己是通過pod的ip地址（mysql -uroot -p123456 -h172.16.16.6），還是通過k8s的命令訪問mysql（kubectl exec -it mysql-kt2v2 bash，然后使用mysql -uroot -p123456查看數據庫信息），還是通過svc對外暴漏端口號的方式（這種方式需要配置mysql的svc的yaml配置文件，我這里沒有對外暴漏端口號，自己需要的話，可以對外進行暴漏的）。
5、如果上面的Java Web項目沒有做持久化之前，如果mysql的pod刪除掉，由於配置了rc，k8s會里面啟動一個mysql，但是會發現新增的數據沒有了，那么如何使用PV、PVC保證數據不丟失呢？這里只是做了mysql的持久化操作。
1 [root@k8s-master ~]# cd k8s/ 2 [root@k8s-master k8s]# ls 3 book-master.war dashboard dashboard.zip deploy health heapster hpa metrics namespace pod rc skydns skydns.zip svc tomcat_demo tomcat_demo.zip volume 4 [root@k8s-master k8s]# cd tomcat_demo/ 5 [root@k8s-master tomcat_demo]# ls 6 book-master2.0.war book-master3.0.war book-master4.0.war book-master5.0.war book-master6.0.war book-master.war Dockerfile mysql-rc.yml mysql-svc.yml tomcat-rc.yml tomcat-svc.yml 7 [root@k8s-master tomcat_demo]# cp ../volume/* . 8 [root@k8s-master tomcat_demo]# ls 9 book-master2.0.war book-master4.0.war book-master6.0.war Dockerfile mysql-svc.yml test-pv.yaml tomcat-svc.yml 10 book-master3.0.war book-master5.0.war book-master.war mysql-rc.yml test-pvc.yaml tomcat-rc.yml 11 [root@k8s-master tomcat_demo]# mv test-pv.yaml mysql-pv.yaml 12 [root@k8s-master tomcat_demo]# mv test-pvc.yaml mysql-pvc.yaml 13 [root@k8s-master tomcat_demo]# ls 14 book-master2.0.war book-master4.0.war book-master6.0.war Dockerfile mysql-pv.yaml mysql-svc.yml tomcat-svc.yml 15 book-master3.0.war book-master5.0.war book-master.war mysql-pvc.yaml mysql-rc.yml tomcat-rc.yml 16 [root@k8s-master tomcat_demo]#
編輯mysql-pv.yaml、mysql-pvc.yaml兩個配置文件，如下所示：
1 apiVersion: v1 2 kind: PersistentVolume 3 metadata: 4 name: mysql 5 labels: 6 type: mysql 7 spec: 8 capacity: 9 storage: 5Gi # 實際生產環境，可以搞大一點的。 10 accessModes: 11 - ReadWriteMany 12 persistentVolumeReclaimPolicy: Recycle 13 nfs: 14 path: "/data/mysql" #拿出一個目錄給Mysql來使用。 15 server: 192.168.110.133 16 readOnly: false
將全部的test替換為mysql的用法，如下所示：
然后創建/data/mysql的目錄，如下所示：
1 [root@k8s-master tomcat_demo]# mkdir /data/mysql 2 [root@k8s-master tomcat_demo]# ls /data/mysql/
然后修改mysql-pvc.yaml配置文件，如下所示：
1 kind: PersistentVolumeClaim 2 apiVersion: v1 3 metadata: 4 name: mysql 5 spec: 6 accessModes: 7 - ReadWriteMany 8 resources: 9 requests: 10 storage: 5Gi
然后依次創建mysq的PV（全局的資源，被綁定到了default/mysqlpvc這個pvc了）、PVC，並進行查看，如下所示：
1 [root@k8s-master tomcat_demo]# ls 2 book-master2.0.war book-master4.0.war book-master6.0.war Dockerfile mysql-pv.yaml mysql-rc.yml tomcat-rc.yml 3 book-master3.0.war book-master5.0.war book-master.war mysql-pvc.yaml mysql-rc-pvc.yml mysql-svc.yml tomcat-svc.yml 4 [root@k8s-master tomcat_demo]# kubectl create -f mysql-pv.yaml 5 persistentvolume "mysql" created 6 [root@k8s-master tomcat_demo]# kubectl create -f mysql-pvc.yaml 7 persistentvolumeclaim "mysql" created 8 [root@k8s-master tomcat_demo]# kubectl get pvc 9 NAME STATUS VOLUME CAPACITY ACCESSMODES AGE 10 mysql Bound mysql 5Gi RWX 6s 11 [root@k8s-master tomcat_demo]# kubectl get pv 12 NAME CAPACITY ACCESSMODES RECLAIMPOLICY STATUS CLAIM REASON AGE 13 mysql 5Gi RWX Recycle Bound default/mysql 15s 14 [root@k8s-master tomcat_demo]#
那么，現在配置mysql的rc，讓它使用卷pvc，這樣就可以完成了數據持久化存儲了。
1 [root@k8s-master tomcat_demo]# cp mysql-rc.yml mysql-rc-pvc.yml 2 [root@k8s-master tomcat_demo]# vim mysql-rc-pvc.yml
使用的方式就是先增加一個目錄，將這個目錄掛載出來，比如將/var/lib/mysql目錄掛載出來，Pod里面可以有多個容器，所以卷的名字有時候需要寫多個，寫完多個之后，在使用卷的時候再來聲明多個，即volumes的名字必須和volumeMounts掛載的名字是一樣的。
具體內容，如下所示：
1 apiVersion: v1 2 kind: ReplicationController 3 metadata: 4 name: mysql 5 spec: 6 replicas: 1 7 selector: 8 app: mysql 9 template: 10 metadata: 11 labels: 12 app: mysql 13 spec: 14 containers: 15 - name: mysql 16 image: 192.168.110.133:5000/mysql:5.7.30 17 ports: 18 - containerPort: 3306 19 env: 20 - name: MYSQL_ROOT_PASSWORD 21 value: '123456' 22 volumeMounts: 23 - name: data 24 mountPath: /var/lib/mysql 25 volumes: 26 - name: data 27 persistentVolumeClaim: 28 claimName: mysql
此時，將mysql-rc-pvc.yml應用一下子，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl apply -f mysql-rc-pvc.yml 2 replicationcontroller "mysql" configured 3 [root@k8s-master tomcat_demo]# kubectl get all -o wide 4 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 5 rc/mysql 1 1 1 35m mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 6 rc/myweb 1 1 1 35m myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 7 8 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 9 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 10 svc/mysql 10.254.182.125 <none> 3306/TCP 35m app=mysql 11 svc/myweb 10.254.188.155 <nodes> 8080:30008/TCP 35m app=myweb 12 13 NAME READY STATUS RESTARTS AGE IP NODE 14 po/mysql-nt1zl 1/1 Running 1 35m 172.16.66.3 k8s-node3 15 po/myweb-c8sf6 1/1 Running 1 35m 172.16.66.5 k8s-node3 16 [root@k8s-master tomcat_demo]#
此時，雖然應用成功了，但是並沒有啟動一個新的mysql的pod，此時，需要將mysql的pod刪除掉，讓rc再創建一個新的mysql的pod，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl delete pod mysql-nt1zl
嗯，很顯然，我的這里出現問題了，刪除之后，新的mysql的pod啟動不起來了，然后我把mysql的rc、svc都刪除了，啟動新的mysql的rc、svc還是啟動不起來了，這里查看一下具體錯誤信息，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl describe pod mysql-p3mcj 2 Name: mysql-p3mcj 3 Namespace: default 4 Node: k8s-node3/192.168.110.135 5 Start Time: Tue, 30 Jun 2020 12:32:35 +0800 6 Labels: app=mysql 7 Status: Pending 8 IP: 9 Controllers: ReplicationController/mysql 10 Containers: 11 mysql: 12 Container ID: 13 Image: 192.168.110.133:5000/mysql:5.7.30 14 Image ID: 15 Port: 3306/TCP 16 State: Waiting 17 Reason: ContainerCreating 18 Ready: False 19 Restart Count: 0 20 Volume Mounts: 21 /var/lib/mysql from data (rw) 22 Environment Variables: 23 MYSQL_ROOT_PASSWORD: 123456 24 Conditions: 25 Type Status 26 Initialized True 27 Ready False 28 PodScheduled True 29 Volumes: 30 data: 31 Type: PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace) 32 ClaimName: mysql 33 ReadOnly: false 34 QoS Class: BestEffort 35 Tolerations: <none> 36 Events: 37 FirstSeen LastSeen Count From SubObjectPath Type Reason Message 38 --------- -------- ----- ---- ------------- -------- ------ ------- 39 2m 2m 1 {default-scheduler } Normal Scheduled Successfully assigned mysql-p3mcj to k8s-node3 40 53s 53s 1 {kubelet k8s-node3} Warning FailedMount Unable to mount volumes for pod "mysql-p3mcj_default(b949a085-ba8a-11ea-af28-000c2919d52d)": timeout expired waiting for volumes to attach/mount for pod "default"/"mysql-p3mcj". list of unattached/unmounted volumes=[data] 41 53s 53s 1 {kubelet k8s-node3} Warning FailedSync Error syncing pod, skipping: timeout expired waiting for volumes to attach/mount for pod "default"/"mysql-p3mcj". list of unattached/unmounted volumes=[data] 42 47s 47s 1 {kubelet k8s-node3} Warning FailedMount MountVolume.SetUp failed for volume "kubernetes.io/nfs/b949a085-ba8a-11ea-af28-000c2919d52d-mysql" (spec.Name: "mysql") pod "b949a085-ba8a-11ea-af28-000c2919d52d" (UID: "b949a085-ba8a-11ea-af28-000c2919d52d") with: mount failed: exit status 32 43 Mounting command: mount 44 Mounting arguments: 192.168.110.133:/data/mysql /var/lib/kubelet/pods/b949a085-ba8a-11ea-af28-000c2919d52d/volumes/kubernetes.io~nfs/mysql nfs [] 45 Output: mount.nfs: Connection refused 46 47 48 [root@k8s-master tomcat_demo]#
出現這種掛載不了的問題，就是nfs沒有配置好，下面可以再配置一下，如下所示：
關於多個centos7操作系統間實現文件數據資源共享（掛載mount網絡文件路徑），這邊通過在服務端配置nfs（網絡文件系統）+rpcbind服務軟件，在三台機器上面確定安裝了nfs，如下所示：
1 [root@k8s-master ~]# rpm -qa|grep nfs 2 nfs-utils-1.3.0-0.66.el7.x86_64 3 libnfsidmap-0.25-19.el7.x86_64 4 [root@k8s-master ~]#
確認三台服務端都安裝配置rpcbind、如下所示：
1 [root@k8s-master ~]# service nfs start 2 Redirecting to /bin/systemctl start nfs.service
在服務端的/etc/exports配置共享路徑，並重啟服務，同時關閉防火牆（比較重要，否則報mount.nfs: Connection timed out）。
1 [root@k8s-master ~]# cat /etc/exports 2 # 共享data目錄，允許192.168.110.*訪問，即允許110段ip地址訪問。讀寫權限，同步，不做root用戶、所有用戶的UID映射 3 /data 192.168.110.0/24(rw,async,no_root_squash,no_all_squash) 4 5 6 [root@k8s-master ~]#
設置/data目錄的權限，如下所示：
1 [root@k8s-master ~]# ll /data/ 2 total 0 3 drwxr-xr-x 2 root root 6 Jun 29 17:21 k8s 4 drwxr-xr-x 5 polkitd root 328 Jun 30 13:04 mysql 5 [root@k8s-master ~]# chmod -R 755 /data/ 6 [root@k8s-master ~]# ll /data/ 7 total 0 8 drwxr-xr-x 2 root root 6 Jun 29 17:21 k8s 9 drwxr-xr-x 5 polkitd root 328 Jun 30 13:04 mysql 10 [root@k8s-master ~]#
在客戶端mount上面服務端分享的nfs路徑/data(綁定在客戶端的/data)，測試成功。
1 [root@k8s-node2 ~]# mount -t nfs 192.168.110.133:/data /data 2 mount.nfs: mount point /data does not exist 3 [root@k8s-node2 ~]# cd mkdir /data 4 -bash: cd: mkdir: No such file or directory 5 [root@k8s-node2 ~]# mkdir /data 6 [root@k8s-node2 ~]# mount -t nfs 192.168.110.133:/data /data 7 [root@k8s-node2 ~]# cd /data/ 8 [root@k8s-node2 data]# ls 9 k8s mysql 10 [root@k8s-node2 data]#
掛載成功之后，重啟兩個客戶端的nfs服務、rpcbind服務，如下所示：
1 [root@k8s-node2 data]# systemctl restart rpcbind.service 2 [root@k8s-node2 data]# systemctl restart nfs.service 3 [root@k8s-node2 data]# 4 5 [root@k8s-node3 data]# systemctl restart rpcbind.service 6 [root@k8s-node3 data]# systemctl restart nfs.service 7 [root@k8s-node3 data]#
此時，再次查看創建的mysql的Pod是否已經創建成功了，如下所示：
1 [root@k8s-master tomcat_demo]# kubectl describe pod mysql-njrhc 2 Name: mysql-njrhc 3 Namespace: default 4 Node: k8s-node3/192.168.110.135 5 Start Time: Tue, 30 Jun 2020 12:42:45 +0800 6 Labels: app=mysql 7 Status: Running 8 IP: 172.16.66.3 9 Controllers: ReplicationController/mysql 10 Containers: 11 mysql: 12 Container ID: docker://a689aeadd94774508b8f384befb62124e28d208801dda204aa4e36e24c476960 13 Image: 192.168.110.133:5000/mysql:5.7.30 14 Image ID: docker-pullable://192.168.110.133:5000/mysql@sha256:0563b36ec2d1a262f79e1d8562e61f642a0f64f93306d8a709047cdea0444d0a 15 Port: 3306/TCP 16 State: Running 17 Started: Tue, 30 Jun 2020 13:03:43 +0800 18 Ready: True 19 Restart Count: 0 20 Volume Mounts: 21 /var/lib/mysql from data (rw) 22 Environment Variables: 23 MYSQL_ROOT_PASSWORD: 123456 24 Conditions: 25 Type Status 26 Initialized True 27 Ready True 28 PodScheduled True 29 Volumes: 30 data: 31 Type: PersistentVolumeClaim (a reference to a PersistentVolumeClaim in the same namespace) 32 ClaimName: mysql 33 ReadOnly: false 34 QoS Class: BestEffort 35 Tolerations: <none> 36 Events: 37 FirstSeen LastSeen Count From SubObjectPath Type Reason Message 38 --------- -------- ----- ---- ------------- -------- ------ ------- 39 27m 27m 1 {default-scheduler } Normal Scheduled Successfully assigned mysql-njrhc to k8s-node3 40 25m 9m 8 {kubelet k8s-node3} Warning FailedMount MountVolume.SetUp failed for volume "kubernetes.io/nfs/25204e19-ba8c-11ea-af28-000c2919d52d-mysql" (spec.Name: "mysql") pod "25204e19-ba8c-11ea-af28-000c2919d52d" (UID: "25204e19-ba8c-11ea-af28-000c2919d52d") with: mount failed: exit status 32 41 Mounting command: mount 42 Mounting arguments: 192.168.110.133:/data/mysql /var/lib/kubelet/pods/25204e19-ba8c-11ea-af28-000c2919d52d/volumes/kubernetes.io~nfs/mysql nfs [] 43 Output: mount.nfs: Connection refused 44 45 46 25m 7m 9 {kubelet k8s-node3} Warning FailedMount Unable to mount volumes for pod "mysql-njrhc_default(25204e19-ba8c-11ea-af28-000c2919d52d)": timeout expired waiting for volumes to attach/mount for pod "default"/"mysql-njrhc". list of unattached/unmounted volumes=[data] 47 25m 7m 9 {kubelet k8s-node3} Warning FailedSync Error syncing pod, skipping: timeout expired waiting for volumes to attach/mount for pod "default"/"mysql-njrhc". list of unattached/unmounted volumes=[data] 48 6m 6m 1 {kubelet k8s-node3} spec.containers{mysql} Normal Pulled Container image "192.168.110.133:5000/mysql:5.7.30" already present on machine 49 6m 6m 1 {kubelet k8s-node3} spec.containers{mysql} Normal Created Created container with docker id a689aeadd947; Security:[seccomp=unconfined] 50 6m 6m 1 {kubelet k8s-node3} spec.containers{mysql} Normal Started Started container with docker id a689aeadd947 51 [root@k8s-master tomcat_demo]# kubectl get all -o wide 52 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 53 rc/mysql 1 1 1 38m mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 54 rc/myweb 1 1 1 1h myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 55 56 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 57 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 58 svc/mysql 10.254.126.11 <none> 3306/TCP 38m app=mysql 59 svc/myweb 10.254.188.155 <nodes> 8080:30008/TCP 1h app=myweb 60 61 NAME READY STATUS RESTARTS AGE IP NODE 62 po/mysql-njrhc 1/1 Running 0 28m 172.16.66.3 k8s-node3 63 po/myweb-c8sf6 1/1 Running 1 1h 172.16.66.5 k8s-node3 64 [root@k8s-master tomcat_demo]#
由於此時，兩個客戶端都掛載了服務器端的目錄，此時查看三台機器的/data目錄，發現里面的內容完全一樣，如下所示：
1 [root@k8s-master ~]# cd /data/ 2 [root@k8s-master data]# ls 3 k8s mysql 4 [root@k8s-master data]# cd mysql/ 5 [root@k8s-master mysql]# ls 6 auto.cnf ca.pem client-key.pem ibdata1 ib_logfile1 mysql private_key.pem server-cert.pem sys 7 ca-key.pem client-cert.pem ib_buffer_pool ib_logfile0 ibtmp1 performance_schema public_key.pem server-key.pem 8 [root@k8s-master mysql]#
可以查看掛載信息，查看一下mysql的pod是在那個機器上啟動的，然后使用命令查看掛載信息。
1 [root@k8s-master tomcat_demo]# kubectl get all -o wide 2 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 3 rc/mysql 1 1 1 46m mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 4 rc/myweb 1 1 1 2h myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 5 6 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 7 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 8 svc/mysql 10.254.126.11 <none> 3306/TCP 46m app=mysql 9 svc/myweb 10.254.188.155 <nodes> 8080:30008/TCP 2h app=myweb 10 11 NAME READY STATUS RESTARTS AGE IP NODE 12 po/mysql-njrhc 1/1 Running 0 36m 172.16.66.3 k8s-node3 13 po/myweb-c8sf6 1/1 Running 1 2h 172.16.66.5 k8s-node3 14 [root@k8s-master tomcat_demo]#
可以在Node3節點使用df -h命令查看掛載信息，如下所示：
1 [root@k8s-node3 mysql]# df -h 2 Filesystem Size Used Avail Use% Mounted on 3 /dev/mapper/centos-root 10G 6.5G 3.6G 65% / 4 devtmpfs 1.2G 0 1.2G 0% /dev 5 tmpfs 1.2G 0 1.2G 0% /dev/shm 6 tmpfs 1.2G 11M 1.2G 1% /run 7 tmpfs 1.2G 0 1.2G 0% /sys/fs/cgroup 8 /dev/sda1 197M 157M 41M 80% /boot 9 tmpfs 229M 12K 229M 1% /run/user/42 10 overlay 10G 6.5G 3.6G 65% /var/lib/docker/overlay2/5265b3c878e49cfa04607df2b3d650eb4a66d2eff93edbabc9bbccffcb3cb5fb/merged 11 shm 64M 0 64M 0% /var/lib/docker/containers/77da48b3cd89ac31f2e1670978d6c4258bf5a5412b337a639776df4a60bc0264/shm 12 overlay 10G 6.5G 3.6G 65% /var/lib/docker/overlay2/ab511d9e7a8f54e2ef11de6e809047bbfde443d1eb3244cbd0f6a8fe32d51552/merged 13 overlay 10G 6.5G 3.6G 65% /var/lib/docker/overlay2/dc3decab78b1c5385384af3199727c41e7e05a96f769288cd133b1831e8b8cff/merged 14 shm 64M 0 64M 0% /var/lib/docker/containers/bad9be6adcd79953768767f69cab35515175fa08ac6cb924dadc40e8c52bd672/shm 15 shm 64M 0 64M 0% /var/lib/docker/containers/6700afcaaaa7115c9079a4ebb988dd6293edd6a5e880bf1b8d1bab4f023ae657/shm 16 overlay 10G 6.5G 3.6G 65% /var/lib/docker/overlay2/2e1480e2559a602d0a0f5437113829ac5f50d2c09f38000aacdea87be0237616/merged 17 overlay 10G 6.5G 3.6G 65% /var/lib/docker/overlay2/98519ce1d9e7d7712cc0aec0482fc0e3e246c9f8dfb9e6cbda8517e97b1a5063/merged 18 tmpfs 229M 0 229M 0% /run/user/0 19 192.168.110.133:/data/mysql 18G 14G 3.9G 79% /var/lib/kubelet/pods/25204e19-ba8c-11ea-af28-000c2919d52d/volumes/kubernetes.io~nfs/mysql 20 overlay 10G 6.5G 3.6G 65% /var/lib/docker/overlay2/9cbf0877f0dc6abef9cfa3aba292066f36f7d7a12f50d642c98be91d62b97c1b/merged 21 shm 64M 0 64M 0% /var/lib/docker/containers/7e03fb4382a25120de8a8714a2c9210dd06b7bb09b94900f963e701d077b5843/shm 22 overlay 10G 6.5G 3.6G 65% /var/lib/docker/overlay2/64614fb76966f8d630d77bc333b24fa67c2078f711a05cf958b2e32c6bab36f5/merged 23 192.168.110.133:/data 18G 14G 3.9G 79% /data 24 [root@k8s-node3 mysql]#
然后可以在web界面錄入幾條新的數據，然后刪除mysql的pod，開始驗證是否已經做到持久化了，如下所示：
刪除mysql的pod，操作如下所示：
1 [root@k8s-master tomcat_demo]# kubectl delete pod mysql-njrhc 2 pod "mysql-njrhc" deleted 3 [root@k8s-master tomcat_demo]# kubectl get all -o wide 4 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 5 rc/mysql 1 1 0 50m mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 6 rc/myweb 1 1 1 2h myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 7 8 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 9 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 10 svc/mysql 10.254.126.11 <none> 3306/TCP 50m app=mysql 11 svc/myweb 10.254.188.155 <nodes> 8080:30008/TCP 2h app=myweb 12 13 NAME READY STATUS RESTARTS AGE IP NODE 14 po/mysql-njrhc 1/1 Terminating 0 40m 172.16.66.3 k8s-node3 15 po/mysql-wldks 0/1 ContainerCreating 0 1s <none> k8s-node3 16 po/myweb-c8sf6 1/1 Running 1 2h 172.16.66.5 k8s-node3 17 [root@k8s-master tomcat_demo]# kubectl get all -o wide 18 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 19 rc/mysql 1 1 1 50m mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 20 rc/myweb 1 1 1 2h myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 21 22 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 23 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 24 svc/mysql 10.254.126.11 <none> 3306/TCP 50m app=mysql 25 svc/myweb 10.254.188.155 <nodes> 8080:30008/TCP 2h app=myweb 26 27 NAME READY STATUS RESTARTS AGE IP NODE 28 po/mysql-njrhc 1/1 Terminating 0 40m 172.16.66.3 k8s-node3 29 po/mysql-wldks 1/1 Running 0 3s 172.16.66.6 k8s-node3 30 po/myweb-c8sf6 1/1 Running 1 2h 172.16.66.5 k8s-node3 31 [root@k8s-master tomcat_demo]# kubectl get all -o wide 32 NAME DESIRED CURRENT READY AGE CONTAINER(S) IMAGE(S) SELECTOR 33 rc/mysql 1 1 1 50m mysql 192.168.110.133:5000/mysql:5.7.30 app=mysql 34 rc/myweb 1 1 1 2h myweb 192.168.110.133:5000/tomcat-book:5.0 app=myweb 35 36 NAME CLUSTER-IP EXTERNAL-IP PORT(S) AGE SELECTOR 37 svc/kubernetes 10.254.0.1 <none> 443/TCP 25d <none> 38 svc/mysql 10.254.126.11 <none> 3306/TCP 50m app=mysql 39 svc/myweb 10.254.188.155 <nodes> 8080:30008/TCP 2h app=myweb 40 41 NAME READY STATUS RESTARTS AGE IP NODE 42 po/mysql-wldks 1/1 Running 0 5s 172.16.66.6 k8s-node3 43 po/myweb-c8sf6 1/1 Running 1 2h 172.16.66.5 k8s-node3 44 [root@k8s-master tomcat_demo]#
然后查看界面上的新錄入的數據，是否還存在，如下所示：
然后，查看一下掛載的目錄也是有內容的，如下所示：
1 [root@k8s-node3 mysql]# ls 2 auto.cnf ca-key.pem client-cert.pem ib_buffer_pool ib_logfile0 ibtmp1 performance_schema public_key.pem server-key.pem 3 book ca.pem client-key.pem ibdata1 ib_logfile1 mysql private_key.pem server-cert.pem sys 4 [root@k8s-node3 mysql]#