k8s学习: 创建 mysql 任务

参考：
手把手教你搞定K8S集群的安装部署

1、创建MySql 容器

创建MySql RC（Replication Controller）文件

mkdir test-mysql && cd test-mysql/

[root@centos7-189 test-mysql]# vim mysql-rc.yaml

apiVersion: v1
kind: ReplicationController         #副本控制器RC
metadata:name: mysql                      #RC的名称,全局唯一
spec:replicas: 1                    #Pod副本的期待数量selector:app: mysql                   #符合目标的Pod拥有此标签template:                      #根据模板创建Pod的副本（实例）metadata:labels:app: mysql                 #Pod副本拥有的标签，对应RC的Selectorspec:containers:                   #Pod内容器的定义部分- name: mysql                 #容器名称image: docker.io/library/mysql:5.7                #容器对应的Docker Imageports:- containerPort: 3306       #容器应用监听的端口号env:- name: MYSQL_ROOT_PASSWORDvalue: "123456"

创建 mysql-rc.

[root@centos7-189 test-mysql]# kubectl create -f mysql-rc.yaml

replicationcontroller/mysql created

查看刚创建的RC

[root@centos7-189 test-mysql]# kubectl get rc

NAME    DESIRED   CURRENT   READY   AGE
mysql   1         1         0       15s

查看刚创建的Pod

[root@centos7-189 test-mysql]# kubectl get pods

NAME          READY   STATUS    RESTARTS   AGE
mysql-tpxn2   1/1     Running   0          96s

查看刚创建的Pod详情

[root@centos7-189 test-mysql]# kubectl describe pod mysql-tpxn2

Name:         mysql-tpxn2
Namespace:    default
Priority:     0
Node:         centos7-186/192.168.1.186
Start Time:   Mon, 15 Nov 2021 14:59:05 +0800
Labels:       app=mysql
Annotations:  <none>
Status:       Running
IP:           10.244.1.2
IPs:IP:           10.244.1.2
Controlled By:  ReplicationController/mysql
...
Events:Type    Reason     Age    From               Message----    ------     ----   ----               -------Normal  Scheduled  2m50s  default-scheduler  Successfully assigned default/mysql-tpxn2 to centos7-186Normal  Pulling    2m48s  kubelet            Pulling image "docker.io/library/mysql:5.7"Normal  Pulled     85s    kubelet            Successfully pulled image "docker.io/library/mysql:5.7" in 1m23.052534372sNormal  Created    85s    kubelet            Created container mysqlNormal  Started    85s    kubelet            Started container mysql

从这里可以看到容器创建在节点 Node: centos7-186/192.168.1.186

ssh 到 192.168.1.186 验证查看

[root@centos7-186 ~]# docker ps |grep mysql

10c4682b4161   mysql                                               "docker-entrypoint.s…"   54 minutes ago      Up 54 minutes                k8s_mysql_mysql-tpxn2_default_b4dd68ab-2fb3-4ada-9069-cdfad8f5287c_0
7643b47c8a8a   registry.aliyuncs.com/google_containers/pause:3.5   "/pause"                 56 minutes ago      Up 56 minutes                k8s_POD_mysql-tpxn2_default_b4dd68ab-2fb3-4ada-9069-cdfad8f5287c_0

2、创建关联的Kubernets Service

创建 service 配置文件

[root@centos7-189 test-mysql]# vim mysql-svc.yaml

apiVersion: v1
kind: Service                 #表名是Kubernetes Service
metadata:name: mysql                 #Service的全局唯一名称
spec:type: NodePortports:- port: 3306               #Service提供服务器的端口号nodePort: 30001          #堆外暴露端口selector:                   #Service对应的Pod拥有这里定义的标签app: mysql

创建 service

[root@centos7-189 test-mysql]# kubectl create -f mysql-svc.yaml

service/mysql created

查看刚创建的Service

[root@centos7-189 test-mysql]# kubectl get services

NAME         TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)          AGE
kubernetes   ClusterIP   10.96.0.1        <none>        443/TCP          30h
mysql        NodePort    10.102.141.170   <none>        3306:30001/TCP   6s

3. 验证 mysql 任务

安装一个 mysql 客户端
如果已经有安装过 mysql-server的可以直接从那里去验证
[root@centos7-189 test-mysql]# yum install mysql -y

连接测试
[root@centos7-189 test-mysql]# mysql -h 192.168.1.189 -u root -P 30001 -p

 MySQL [(none)]> show databases;+--------------------+| Database           |+--------------------+| information_schema || mysql              || performance_schema || sys                |+--------------------+4 rows in set (0.00 sec)MySQL [(none)]> use mysql;Reading table information for completion of table and column namesYou can turn off this feature to get a quicker startup with -ADatabase changedMySQL [mysql]> show tables;...MySQL [mysql]> desc user;...MySQL [mysql]> select User,Host from user;+---------------+-----------+| User          | Host      |+---------------+-----------+| root          | %         || mysql.session | localhost || mysql.sys     | localhost || root          | localhost |+---------------+-----------+4 rows in set (0.00 sec)MySQL [mysql]> exit

清理

kubectl get rc

NAME    DESIRED   CURRENT   READY   AGE
mysql   1         1         1       4d1h

kubectl get rs

No resources found in default namespace.

kubectl delete rc mysql

replicationcontroller "mysql" deleted