k8s集群安装 mysql主从 k8s搭建mysql主从

转载

云端小梦 2023-08-28 16:12:09

文章标签 k8s集群安装 mysql主从 kubernetes mysql多主 mysql MySQL docker 文章分类 MySQL 数据库

愿你，忠于自己，活得像自己。

清单：

Name

Version

CentOS

Kubernetes

1.9.0

Docker

17.09.1-ce

MySQL

5.7

前言

令我始料不及的出差活动中，开始接触Kubernetes并被要求搭建基于此的MySQL主从集群，由于笔者在Linux、Kubernetes等方面都是小白，故此展开了填坑活动，写本文目的只是为了让其他程序猿少踩坑，下面简单介绍下MySQL主从集群。

我们用MySQL集群的分布式部署来实现MySQL主从模式，在MySQL集群中，Master节点主要负责数据的分发和slave节点的管理。因此Master节点主要负责数据的写入和分发(包括insert、update、delete)。而slave节点主要负责数据的读取(包括select)。基本的master和slave的分工作业，如下图所示。

k8s集群安装 mysql主从 k8s搭建mysql主从_MySQL

MySQL集群架构

MySQL集群在主从模式下实现一台服务充当主服务器，其他一台或者多台服务器充当从服务器。下面我们开始搭建。

一、安装MySQL

若已安装且知道密码请直接看构建Docker镜像部分

若已安装但忘记密码请直接看步骤13

检查是否已经安装MySQL

rpm -qa | grep mysql

下载MySQL源安装包

# wget http://dev.mysql.com/get/mysql57-community-release-el7-8.noarch.rpm

安装MySQL源

# yum localinstall mysql57-community-release-el7-8.noarch.rpm

检查MySQL源是否安装成功

# yum repolist enabled | grep "mysql.*-community.*"

k8s集群安装 mysql主从 k8s搭建mysql主从_k8s集群安装 mysql主从_02

yum资源列表

安装MySQL

# yum install mysql-community-server

启动MySQL服务

# systemctl start mysqld

设置开机启动(如不需要可跳过)

# systemctl enable mysqld

# systemctl daemon-reload

获取MySQL默认密码

# grep 'temporary password' /var/log/mysqld.log

k8s集群安装 mysql主从 k8s搭建mysql主从_mysql_03

MySQL默认密码

修改密码(需包含大小写英文、数字、特殊字符且大于8位)

# mysql -u root -p
# set password for 'root'@'localhost'=password('MySQL@lipuan.2018');
配置默认编码utf8,文件/etc/my.cnf中[mysqld]下加入
character_set_server=utf8
init_connect='SET NAMES utf8'

关键目录

配置文件: /etc/my.cnf

日志文件: /var/log//var/log/mysqld.log

服务启动脚本: /usr/lib/systemd/system/mysqld.service

socket文件: /var/run/mysqld/mysqld.pid

忘记密码操作，文件/etc/my.cnf中[mysqld]下加入

skip-grant-tables

重启MySQL

# service mysqld restart

转至步骤9修改密码，成功后删除文件/etc/my.cnf中的skip-grant-tables

二、构建Docker镜像

master配置

文件/etc/my.cnf中[mysqld]下添加配置

log-bin=mysql-bin

server-id=1

重启MySQL

# service mysqld restart

创建同步账号

# mysql -u root -p

# create user 'sync'@'%' identified by 'MySQL@lipuan.2018';

赋予同步账号远程权限

# grant replication slave on *.* to 'sync'@'%' identified by 'MySQL@lipuan.2018';

slave配置

文件/etc/my.cnf中[mysqld]下添加配置

log-bin=mysql-bin

server-id=2

重启MySQL

# service mysqld restart

配置主机IP

# mysql -u root -p

# change master to master_host='x.x.x.x',master_user='sync',master_password='MySQL@lipuan.2018';

注意: server-id为主机标识，不能重复。x.x.x.x'为master服务器IP

准备master镜像

下载MySQL官方Docker镜像文件，并解压

# wget https://codeload.github.com/docker-library/mysql/zip/master
# unzip master
# mkdir /home/lipuan/mysqlDockerFile
# cp -Rf mysql-master/5.7/Dockerfile /home/lipuan/mysqlDockerFile
# cp -Rf mysql-master/5.7/docker-entrypoint.sh /home/lipuan/mysqlDockerFile
# rm -rf mysql-master
Dockerfile中添加，位置如下图所示
RUN sed -i '/\[mysqld\]/a server-id=1\nlog-bin' /etc/mysql/mysql.conf.d/mysqld.cnf

k8s集群安装 mysql主从 k8s搭建mysql主从_mysql_04

Dockerfile-master

docker-entrypoint.sh中添加，位置如下图所示
echo "CREATE USER '$MYSQL_REPLICATION_USER'@'%' IDENTIFIED BY '$MYSQL_REPLICATION_PASSWORD' ;" | "${mysql[@]}"
echo "GRANT REPLICATION SLAVE ON *.* TO '$MYSQL_REPLICATION_USER'@'%' IDENTIFIED BY '$MYSQL_REPLICATION_PASSWORD' ;" | "${mysql[@]}"
echo 'FLUSH PRIVILEGES ;' | "${mysql[@]}"

k8s集群安装 mysql主从 k8s搭建mysql主从_k8s集群安装 mysql主从_05

entrypoint-master

准备slave的镜像

下载MySQL官方Docker镜像文件

# wget https://codeload.github.com/docker-library/mysql/zip/master
# unzip master
# mkdir /home/lipuan/mysqlDockerFile
# cd ~
# cp -Rf mysql-master/5.7/Dockerfile /home/lipuan/mysqlDockerFile
# cp -Rf mysql-master/5.7/docker-entrypoint.sh /home/lipuan/mysqlDockerFile
# rm -rf mysql-master
Dockerfile中添加，位置如下图所示
RUN RAND="$(date +%s | rev | cut -c 1-2)$(echo ${RANDOM})" && sed -i '/\[mysqld\]/a server-id='$RAND'\nlog-bin' /etc/mysql/mysql.conf.d/mysqld.cnf

此处server-id用的是随机数

k8s集群安装 mysql主从 k8s搭建mysql主从_kubernetes mysql多主_06

Dockerfile-slave

2.3 docker-entrypoint.sh中添加，位置如下图所示

echo "STOP SLAVE;" | "${mysql[@]}"
echo "CHANGE MASTER TO master_host='$MYSQL_MASTER_SERVICE_HOST', master_user='$MYSQL_REPLICATION_USER', master_password='$MYSQL_REPLICATION_PASSWORD' ;" | "${mysql[@]}"
echo "START SLAVE;" | "${mysql[@]}"

slave配置中,master_host一项用的是$MYSQL_MASTER_SERVICE_HOST，这个环境变量(enviromnent variable)是由k8s生成的。

k8s集群安装 mysql主从 k8s搭建mysql主从_kubernetes mysql多主_07

entrypoint-slave.png
构建master镜像
# cd /home/lipuan/mysqlDockerFile/
# docker build -t paulliu/mysql-master:0.1 .
构建slave镜像
# cd /home/lipuan/mysqlDockerFile/
# docker build -t paulliu/mysql-slave:0.1 .
上传镜像
# docker login
# docke push paulliu/mysql-master:0.1
# docke push paulliu/mysql-slave:0.1
三、MySQL集群部署
# cd /home/lipuan/DockerBuild此后内容若无指出均在此目录下执行
此部分操作，所有yaml文件缩进空格必须严格，否则无法构建成功
master
新建mysql-master-rc.yaml文件
# touch mysql-master-rc.yaml
添加内容
apiVersion: v1
kind: ReplicationController
metadata:
name: mysql-master
labels:
name: mysql-master
spec:
replicas: 1
selector:
name: mysql-master
template:
metadata:
labels:
name: mysql-master
spec:
containers:
- name: master
image: paulliu/mysql-master:0.1
ports:
- containerPort: 3306
env:
- name: MYSQL_ROOT_PASSWORD
value: "MySQL@lipuan.2018"
- name: MYSQL_REPLICATION_USER
value: "sync"
- name: MYSQL_PASSWORD
value: "MySQL@lipuan.2018"
新建mysql-master-service.yaml文件
# touch mysql-master-service.yaml
添加内容
apiVersion: v1
kind: Service
metadata:
name: mysql-master
labels:
name: mysql-master
spec:
ports:
- port: 3306
targetPort: 3306
selector:
name: mysql-master
部署MySQL master服务
# kubectl create -f mysql-master-rc.yaml
# kubectl create -f mysql-master-service.yaml
查看运行情况
# kubectl get pods,service,rc
slave
新建mysql-slave-rc.yaml文件
# touch mysql-slave-rc.yaml
添加内容
apiVersion: v1
kind: ReplicationController
metadata:
name: mysql-slave
labels:
name: mysql-slave
spec:
replicas: 1
selector:
name: mysql-slave
template:
metadata:
labels:
name: mysql-slave
spec:
containers:
- name: master
image: paulliu/mysql-slave:0.1
ports:
- containerPort: 3306
env:
- name: MYSQL_ROOT_PASSWORD
value: "MySQL@lipuan.2018"
- name: MYSQL_REPLICATION_USER
value: "sync"
- name: MYSQL_PASSWORD
value: "MySQL@lipuan.2018"
新建mysql-slave-service.yaml文件
# touch mysql-slave-service.yaml
添加内容
apiVersion: v1
kind: Service
metadata:
name: mysql-slave
labels:
name: mysql-slave
spec:
ports:
- port: 3306
targetPort: 3306
selector:
name: mysql-slave
部署MySQL slave服务
# kubectl create -f mysql-slave-rc.yaml
# kubectl create -f mysql-slave-service.yaml
查看运行情况
# kubectl get pods,service,rc

写在文末

写到这里基于Kubernetes的MySQL主从集群就搭建成功了，如果有哪位朋友对于其中步骤不是很清楚，欢迎互相学习。

本文是笔者首次写技术博客，如有错漏等问题，还望各位大大指出批评！

本文章为转载内容，我们尊重原作者对文章享有的著作权。如有内容错误或侵权问题，欢迎原作者联系我们进行内容更正或删除文章。