kubernetes下安装mysql

参考文档：https://blog.csdn.net/sealir/article/details/81177747

注：有mysql安装在k8s集群内，集群外且通过k8s service endpoint代理外部mysql服务供内k8s内部集群访问两种方式，本文为第二种

一，先在k8s-node上docker安装mysql,并远程连接可用

1.下载mysql镜像

如果很慢请参考docker pull centos慢问题的解决方案

[root@k8s-node1 ~]# docker pull mysql:5.7
5.7: Pulling from library/mysql
27833a3ba0a5: Pull complete
864c283b3c4b: Pull complete
cea281b2278b: Pull complete
8f856c14f5af: Pull complete
9c4f38c23b6f: Pull complete
1b810e1751b3: Pull complete
5479aaef3d30: Pull complete
1d924ec3d520: Pull complete
1ab7ae63ac60: Pull complete
08aa5f3680e9: Pull complete
a832d0a0972a: Pull complete
Digest: sha256:dba5fed182e64064b688ccd22b2f9cad4ee88608c82f8cff21e17bab8da72b81
Status: Downloaded newer image for mysql:5.7
[root@k8s-node1 ~]# docer images
-bash: docer: 未找到命令
[root@k8s-node1 ~]# docker images
REPOSITORY                           TAG                 IMAGE ID            CREATED             SIZE
mytomcat                             v8                  f1332ae3f570         days ago         463MB
mytomcat                             v9                  f1332ae3f570         days ago         463MB
tomcat                                                  f1332ae3f570         days ago         463MB
mysql                                5.7                 98455b9624a9         weeks ago         372MB
k8s.gcr.io/kube-proxy                v1.14.0             5cd54e388aba         weeks ago         .1MB
k8s.gcr.io/kube-controller-manager   v1.14.0             b95b1efa0436         weeks ago         158MB
k8s.gcr.io/kube-scheduler            v1.14.0             00638a24688b         weeks ago         .6MB
k8s.gcr.io/kube-apiserver            v1.14.0             ecf910f40d6e         weeks ago         210MB
quay.io/coreos/flannel               v0.11.0-amd64       ff281650a721         months ago        .6MB
k8s.gcr.io/coredns                   1.3.               eb516548c180         months ago        .3MB
k8s.gcr.io/etcd                      3.3.              2c4adeb21b4f         months ago        258MB
k8s.gcr.io/pause                     3.1                 da86e6ba6ca1         months ago       742kB
[root@k8s-node1 ~]# 

2.启动，-v <dir>:/var/lib/mysql，将宿主机目录dir挂载到容器中

[root@k8s-node1 mysql]# docker run -d -p : -v /var/local/mysql:/var/lib/mysql -e MYSQL_ROOT_PASSWORD=mysql --name docker-mysql mysql:5.7
87b7410ea379136b3743e194bb312b1bb6fe02abe73e706e04c68856aecc507a
[root@k8s-node1 mysql]# 

进入mysql container

[root@k8s-node1 mysql]# docker ps -a
CONTAINER ID        IMAGE                  COMMAND                  CREATED              STATUS                     PORTS                               NAMES
87b7410ea379        mysql:5.7              "docker-entrypoint.s…"   About a minute ago   Up About a minute          0.0.0.0:->/tcp, /tcp   docker-mysql
[root@k8s-node1 mysql]# docker exec -it 87b7410ea379 /bin/bash
root@87b7410ea379:/# mysql -uroot -pmysql
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is
Server version: 5.7. MySQL Community Server (GPL)

Copyright (c) , , Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> 
mysql> exit
Bye
root@87b7410ea379:/# exit
exit
[root@k8s-node1 mysql]# 

3.远程连接

二，到k8s master创建server,endpoint代理访问

1.到k8s-master上验证是否可以连接，前提是已安装mysql客户端（如果没有centos7安装mysql客户端）

[root@k8s-master master]# mysql -h192.168.111. -P3306 -uroot -pmysql
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MySQL connection id is
Server version: 5.7. MySQL Community Server (GPL)

Copyright (c) , , Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MySQL [(none)]> exit
Bye
[root@k8s-master master]# 

2.创建mysql-out.svc.yaml文件

[root@k8s-master ~]# cat mysql-out-svc.yaml
apiVersion: v1
kind: Service
metadata:
  name: mysql-out-svc
spec:
  ports:
    - port:
      protocol: TCP
      targetPort: 

---
apiVersion: v1
kind: Endpoints
metadata:
  name: mysql-out-svc
subsets:
  - addresses:
      - ip: "192.168.111.131"
    ports:
      - port:
[root@k8s-master ~]# 

在service中,各项配置意义

spec:
  type: NodePort      #这里代表是NodePort类型的,另外还有ingress,LoadBalancer
  ports:
  - port: 80          #这里的端口和clusterIP(kubectl describe service service-hello中的IP的port)对应，即在集群中所有机器上curl 10.98.166.242:80可访问发布的应用服务。
    targetPort: 8080  #端口一定要和container暴露出来的端口对应，nodejs暴露出来的端口是8081，所以这里也应是8081
    protocol: TCP
    nodePort: 31111   # 所有的节点都会开放此端口，此端口供外部调用。
  selector:
    run: hello         #这里选择器一定要选择容器的标签，之前写name:kube-node是错的。

3.启动service

[root@k8s-master ~]# kubectl create -f mysql-out-svc.yaml
service/mysql-out-svc created
endpoints/mysql-out-svc created
[root@k8s-master ~]# kubectl get services -o wide
NAME            TYPE        CLUSTER-IP       EXTERNAL-IP   PORT(S)        AGE   SELECTOR
kubernetes      ClusterIP   10.96.0.1        <none>        /TCP        8d    <none>
mysql-out-svc   ClusterIP   10.111.241.185   <none>        /TCP       18s   <none>
service-hello   NodePort    10.98.166.242    <none>        :/TCP   8d    run=hello
[root@k8s-master ~]# kubectl get endpoints -o wide
NAME            ENDPOINTS                           AGE
kubernetes      192.168.111.130:                8d
mysql-out-svc   192.168.111.131:                37s
service-hello   10.244.1.36:,10.244.1.37:   8d

因为使用的是k8s集群外部mysql服务，然后用service代理，让k8s集群内的其它service（如service-hello）可通过 cluster-ip:port（10.111.241.185:3306）来访问外部的mysql服务
所以此外并没有生成mysql 的pod

[root@k8s-master ~]# kubectl get pods -o wide
NAME                     READY   STATUS    RESTARTS   AGE     IP            NODE        NOMINATED NODE   READINESS GATES
hello-5cd4456b66-gstq6   /     Running             7d17h   10.244.1.36   k8s-node1   <none>           <none>
hello-5cd4456b66-sb5px   /     Running             7d17h   10.244.1.37   k8s-node1   <none>           <none>

4.在k8s-master上也可以通过 cluster-ip:port（10.111.241.185:3306）来访问外部的mysql服务

[root@k8s-master ~]# mysql -h10.111.241. -P3306 -uroot -pmysql
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MySQL connection id is
Server version: 5.7. MySQL Community Server (GPL)

Copyright (c) , , Oracle, MariaDB Corporation Ab and others.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

MySQL [(none)]> 

到此，k8s上安装msyql完成