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Kubernetes(k8s)持久化存储PV和PVC

1、K8s为什么要使用存储?

答:k8s中的副本控制器保证了pod的始终存储,却保证不了Pod中的数据。只有启动一个新pod的,之前pod中的数据会随着容器的删掉而丢失。k8s中的rc启动指定数量的Pod,当某个Pod死掉了,会在新的节点启动新的Pod,k8s中想要实现数据持久化,需要使用一个叫做共享存储的,让Pod里面的数据挂载到这个共享存储上面,就算在新的节点启动新的Pod,依然可以保证数据不丢失。

 

2、k8s中的PV和PVC的概念。

答:PersistentVolume(简称为PV,持久化存储),由管理员添加的一个存储的描述,是一个全局资源,没有namespace的限制,包含存储的类型,存储的大小和访问模式等等。它的生命周期独立于Pod,例如当使用它的Pod销毁时对PV没有影响。
  PersistentVolumeClaim(简称为PVC),是Namespace里面的资源,描述对PV的一个请求。请求信息包含存储大小,访问模式等等。注意,PV和PVC是一一绑定的。

3、首先这里创建PV使用到的是NFS,这里首先安装一下NFS,如下所示:

需要Master主节点先安装NFS服务端,在所有Node节点安装NFS客户端,不然Pod无法使用,因为挂载不上,在三台机器都执行下面的命令即可。

 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 ~]# 

在三台机器都要安装nfs-utils的包的,然后在服务器端,开始配置配置文件/etc/exports,如下所示:

1 [root@k8s-master ~]# vim /etc/exports

配置内容,如下所示:

1 # 共享data目录,允许192.168.110.*访问,即允许110段ip地址访问。读写权限,同步,不做root用户、所有用户的UID映射
2 /data 192.168.110.0/24(rw,async,no_root_squash,no_all_squash)

创建/data/目录下面的一个目录,如下所示:

1 [root@k8s-master ~]# cat /etc/exports
2 # 共享data目录,允许192.168.110.*访问,即允许110段ip地址访问。读写权限,同步,不做root用户、所有用户的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 ~]# 

然后重启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 ~]# 

在另外两个节点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 ~]# 

下面开始创建一个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

配置内容,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

开始创建这个PV,并进行查看,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]# 

再创建一个5Gi的PV,修改一下配置文件,然后进行创建,名称必须不一样,标签可以一样的,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]# 

开始创建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]# 

此时,可以发现pvc已经绑定到了testpv2这个PV上面了,pvc优先绑定到容量小的pv上面的。自己也可以再创建一个6G的PV,然后再创建一个7G的PVC,可以发现这个PVC会绑定到10G的这个PV上面了的。

 

4、K8s持久化实战,自己可以参考一下这篇https://www.cnblogs.com/wangxu01/articles/11411113.html

这里首先引用一下https://www.cnblogs.com/biehongli/p/13150609.html,使用k8s运行Java Web项目,这里紧接着这个链接的操作,创建一个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' # 如果已经安装了dns服务,那么这里可以直接使用mysql的svc即Service的名称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]# 

然后可以通过Navicat连上这个机器的Mysql,然后创建一个数据库,将sql执行一下,就完成了Mysql的任务了,下面就是将web项目搞到tomcat里面,然后使用k8s启动tomcat就行了。

怎么创建java web端的镜像呢,首先镜像要运行在tomcat里面的,创建镜像的第一步,说明继承自那个基础镜像,因为程序是Java web程序,肯定是需要用到tomcat的,先将tomcat的镜像下载下来。

1 [root@k8s-master tomcat_demo]# vim Dockerfile

配置内容,如下所示:

1 # 第一步,说明继承那个基础镜像,tomcat作为基础镜像。此处告诉Docker我要做自己的镜像,以tomcat镜像为起点。
2 from docker.io/tomcat:latest3 
4 # 第二步,描述镜像的所有者,可以省略。
5 MAINTAINER biehl biehl@qq.com
6 
7 # 第三步,将自己的web应用放到镜像里面,将本地的war包拷贝到tomcat的webapps目录下面。可以看看程序是否可以随着tomcat启动起来。
8 COPY book-master.war /usr/local/tomcat/webapps

dokcer build命令就是用来执行Dockerfile里面所描述的每一件事情,最终会把docker镜像给我们构建出来。

 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

然后可以将这个上传到私有仓库里面,方便其他Node节点下载,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

然后创建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]# 

访问地址http://192.168.110.133:30008/,报错了,源服务器未能找到目标资源的表示或者是不愿公开一个已经存在的资源表示。

还按照之前搞过的,这次找到是那台机器运行了这个Pod,找到了,然后将webapps.dist目录里面的文件拷贝到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# 

访问地址http://192.168.110.133:30008/,如下所示:

访问地址http://192.168.110.133:30008/book-master/,如下所示:

需要注意的是,我的项目连接的mysql的地址就是Master节点的ip地址的,然后Pod服务与服务之间的访问,比如tomcat访问mysql的是tomcat连的是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

运行项目可以正常运行,简单的效果,如下所示:

查看kubernetes dashboard的界面如下所示:

点击可以查看详细的日志信息,如下所示:

可以通过命令对Pod的副本数进行调整,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 ~]# 

创建的时间大概几十秒吧,我的私有仓库包含项目的tomcat有七八百兆左右,也可以通过kubernetes dashboard进行查看,如下所示:

后来测试如何保证删除了mysql的pod如何保证数据不丢失的时候,发现一个问题的,我发现不管我怎么删除mysql的Pod之后,rc会立马启动一个mysql,但是我的数据就是没有丢失呢,我此时还没有做PV、PVC呢,后来发现原来我用的是192.168.110.133机器安装的mysql,也是服气子了,所以重新改了配置文件,然后重新创建mysql、myweb。下面开始创建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]# 

创建完毕Mysql之后,如果通过k8s进入到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> 

同样,也可以通过访问Pod的ip地址来访问Mysql服务的,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> 

然后可以创建自己的数据表,由于执行创建数据表的sql过长,这里进行了省略哦,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> 

创建好数据表进行查看,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> 

然后创建已经将2.x版本的项目打到tomcat的rc、svc,如下所示:

注意:其实这里为了搞清楚java项目的mysql的ip地址、端口号这些填啥,我已经打了很多版本了,最新的是4.0版本的了,操作几乎一样,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]# 

然后开始访问地址http://192.168.110.133:30008/book-master2.0/,k8s访问tomcat报错,源服务器未能找到目标资源的表示或者是不愿公开一个已经存在的资源表示。还可以按照上面的方法进行解决,这里再贴下步骤了,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,我这里的java项目使用的就是svc/mysql的ip地址10.254.133.12,然后tomcat-rc.yml由于配置了dns,直接使用的是mysql这个svc的名称。

 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名称,如果没有配置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项目的连接mysql数据库的ip地址和端口号直接使用的mysql的svc的ip地址,端口号,这样的缺点就是每次创建mysql都会随机分配一个新的ip地址,就很麻烦的。

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

如果按照上面的链接k8s创建的mysql,如果mysql的svc即service重新建一个,会导致这个java连不上mysql数据库的,我又使用了下面这个配置连接k8s里面的mysql数据库,这里使用了svc(service)的名称来代替,如果配置好了dns的话,是可以这样配置的,我的tomcat-rc.yml连接k8s创建的mysql就是这样配置的,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

此时我的tomcat-rc.yml是这个样子的。

 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]# 

此时,删除mysql的pod验证一下,自己java web如此配置连接k8s里面的Mysql是否正常,然后验证数据没有持久化会造成数据丢失吗?

 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]# 

最终会发现你删除的那个mysql的pod被删除之前,新的mysql的pod已经创建成功了的。

 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]# 

然后登录mysql,这里通过mysql的pod的ip地址进行登录,发现数据已经丢失了,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的命令进入到Mysql,进行登录,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,这个svc配置了NodePort方式,对外暴漏了端口号,那么在服务器可以通过访问暴漏的端口号,和服务器的ip地址,已经mysql的账号,密码就可以访问k8s里面创建的mysql了的。总之,访问方式有很多种,自己理清楚,自己是通过pod的ip地址(mysql -uroot -p123456 -h172.16.16.6),还是通过k8s的命令访问mysql(kubectl exec -it mysql-kt2v2 bash,然后使用mysql -uroot -p123456查看数据库信息),还是通过svc对外暴漏端口号的方式(这种方式需要配置mysql的svc的yaml配置文件,我这里没有对外暴漏端口号,自己需要的话,可以对外进行暴漏的)。

 

5、如果上面的Java Web项目没有做持久化之前,如果mysql的pod删除掉,由于配置了rc,k8s会里面启动一个mysql,但是会发现新增的数据没有了,那么如何使用PV、PVC保证数据不丢失呢这里只是做了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]# 

编辑mysql-pv.yaml、mysql-pvc.yaml两个配置文件,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 # 实际生产环境,可以搞大一点的。
10   accessModes:
11     - ReadWriteMany
12   persistentVolumeReclaimPolicy: Recycle
13   nfs:
14     path: "/data/mysql" #拿出一个目录给Mysql来使用。
15     server: 192.168.110.133
16     readOnly: false

将全部的test替换为mysql的用法,如下所示:

然后创建/data/mysql的目录,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

然后依次创建mysq的PV(全局的资源,被绑定到了default/mysqlpvc这个pvc了)、PVC,并进行查看,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,现在配置mysql的rc,让它使用卷pvc,这样就可以完成了数据持久化存储了。

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个目录,将这个目录挂载出来,比如将/var/lib/mysql目录挂载出来,Pod里面可以有多个容器,所以卷的名字有时候需要写多个,写完多个之后,在使用卷的时候再来声明多个,即volumes的名字必须和volumeMounts挂载的名字是一样的。

具体内容,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

此时,将mysql-rc-pvc.yml应用一下子,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]# 

此时,虽然应用成功了,但是并没有启动一个新的mysql的pod,此时,需要将mysql的pod删除掉,让rc再创建一个新的mysql的pod,如下所示:

1 [root@k8s-master tomcat_demo]# kubectl delete pod mysql-nt1zl

嗯,很显然,我的这里出现问题了,删除之后,新的mysql的pod启动不起来了,然后我把mysql的rc、svc都删除了,启动新的mysql的rc、svc还是启动不起来了,这里查看一下具体错误信息,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]# 

出现这种挂载不了的问题,就是nfs没有配置好,下面可以再配置一下,如下所示:

关于多个centos7操作系统间实现文件数据资源共享(挂载mount网络文件路径),这边通过在服务端配置nfs(网络文件系统)+rpcbind服务软件,在三台机器上面确定安装了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 ~]# 

确认三台服务端都安装配置rpcbind、如下所示:

1 [root@k8s-master ~]# service  nfs  start
2 Redirecting to /bin/systemctl start nfs.service

在服务端的/etc/exports配置共享路径,并重启服务,同时关闭防火墙(比较重要,否则报mount.nfs: Connection timed out)。

1 [root@k8s-master ~]# cat /etc/exports
2 # 共享data目录,允许192.168.110.*访问,即允许110段ip地址访问。读写权限,同步,不做root用户、所有用户的UID映射
3 /data 192.168.110.0/24(rw,async,no_root_squash,no_all_squash)
4 
5 
6 [root@k8s-master ~]# 

设置/data目录的权限,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 ~]# 

在客户端mount上面服务端分享的nfs路径/data(绑定在客户端的/data),测试成功。

 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]# 

挂载成功之后,重启两个客户端的nfs服务、rpcbind服务,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]# 

此时,再次查看创建的mysql的Pod是否已经创建成功了,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]# 

由于此时,两个客户端都挂载了服务器端的目录,此时查看三台机器的/data目录,发现里面的内容完全一样,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]# 

可以查看挂载信息,查看一下mysql的pod是在那个机器上启动的,然后使用命令查看挂载信息。

 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节点使用df -h命令查看挂载信息,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界面录入几条新的数据,然后删除mysql的pod,开始验证是否已经做到持久化了,如下所示:

删除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录入的数据,是否还存在,如下所示:

然后,查看一下挂载的目录也是有内容的,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]# 

 

posted on 2020-07-02 21:48  别先生  阅读(216)  评论(0编辑  收藏