Mysql

关注公众号 jb51net

关闭
首页 > 数据库 > Mysql > MySQL双主高可用

MySQL双主高可用详解

作者：大新屋

文章介绍了在CentOS7.9上部署MySQL双主架构及Keepalived高可用方案,涵盖主机规划、系统优化、MySQL自动安装、主从同步配置和Keepalived部署步骤,强调版本兼容性与脚本执行要求

主机规划：

主机名称IPKeepalived操作系统安装服务安装路径
mysql01192.168.91.61192.168.91.100CentOS 7.9MySQL 8.0.28 Keepalived v1.3.5/usr/local/mysql
mysql02192.168.91.62192.168.91.100CentOS 7.9MySQL 8.0.28 Keepalived v1.3.5/usr/local/mysql

架构图：

一、系统初基础优化（mysql01和mysql02都操作）

systemctl stop firewalld
systemctl disable firewalld
sed -i 's@SELINUX=enforcing@SELINUX=disabled@g' /etc/selinux/config
grep -i "^selinux=" /etc/selinux/config
setenforce 0
getenforce

cat >> /etc/security/limits.conf << EOF
*   soft    nproc    65535
*   hard    nproc    65535
*   soft    nofile    65535
*   hard    nofile    65535
EOF

cat >> /etc/hosts << EOF
192.168.91.61  mysql01
192.168.91.62  mysql02
EOF

二、脚本自动安装MySQL二进制软件包（mysql01和mysql02都操作）

1、下载MySQL二进制软件包

wget https://downloads.mysql.com/archives/get/p/23/file/mysql-8.0.28-linux-glibc2.12-x86_64.tar.xz -P /mnt/

2、创建自动安装MySQL二进制软件包脚本

注意：此脚本只适合CentOS 7.9版本操作系统和MySQL 8.0版本数据库安装，MySQL二进制软件包一定要与自动安装脚本放在同一个目录上执行，否则执行会报错。

[root@mysql01 ~]# vim /mnt/mysql_install.sh

#!/bin/bash
# Description: MySQL binary pack install
# Version: 1.0

#################################################################################
# Prompt:  MySQL binary pack must put same directory with scripts.           
# 提示:    把MySQL 二进制软件包与该脚本放在同一个目录下，再执行该脚本进行安装.  
#################################################################################

. /etc/profile

export PATH=$PATH
RED='\033[1;31;5m'
RES='\033[0m'
MYSQL_COUNT=$(ss -tlunp | grep mysqld | wc -l)
MYSQL_PWD=$(pwd)
MYSQL_PACK="mysql-8.0.28-linux-glibc2.12-x86_64.tar.xz"    ### 只需要把这个软件包名称替换成你所下载的软件包名称一致
MYSQL_PATH="/usr/local/${MYSQL_PACK//-linux*/}"
MYSQL_LINK="/usr/local/mysql"


### check MySQL if installed
if [ $MYSQL_COUNT -ne 0 ];then
   echo -e "${RED} MySQL program is running ${RES}"
   exit 1
fi
### check MySQL directory is exits
if [ -d /usr/local/mysql* ];then 
   echo -e "${RED} MySQL directory is exits ${RES}"
   exit 1
fi
### check MySQL binary pack if exist
if [ ! -f ${MYSQL_PWD}/${MYSQL_PACK} ];then
   echo -e "${RED} Current directory is not MySQL binary pack,Please copy it ${RES}"
   exit 1
fi

### install MySQL depend pack
yum -y install ncurses-devel libaio-devel gcc gcc++ net-tools > /dev/null 2>&1
if [ $? -ne 0 ];then
   echo -e "${RED} Yum install is failure,Please check network if surf the internet ${RES}"
   exit 1
fi

### discompress MySQL binary pack
tar xf ${MYSQL_PWD}/${MYSQL_PACK} -C /usr/local/
mv /usr/local/mysql-* ${MYSQL_PATH}
ln -s ${MYSQL_PATH} ${MYSQL_LINK}
mkdir -p ${MYSQL_LINK}/data
mkdir -p ${MYSQL_LINK}/logs


###judge my.cnf configuration file if exits
if [ -f /etc/my.cnf ];then
   mv /etc/my.cnf /tmp/
fi

### compile my.cnf configuration file
cat << EOF > /etc/my.cnf
[mysqld]
#server-id=1
mysqlx_socket=/tmp/mysqlx.sock
basedir=/usr/local/mysql
datadir=/usr/local/mysql/data
socket=/tmp/mysql.sock
pid_file=/tmp/mysqld.pid
log_error=/usr/local/mysql/logs/error.log
log-bin=/usr/local/mysql/logs/mysql.bin
character-set-server=utf8mb4

max_connections=500
max_connect_errors=1000
port=3306
mysqlx_port=33060
EOF

### create MySQL virtual user
id mysql > /dev/null 2>&1
if [ $? -ne 0 ];then
  useradd -s /bin/nologin -M mysql
fi

### MySQL directory to mandate mysql user
chown -R mysql:mysql /usr/local/mysql*

### initialize MySQL
${MYSQL_LINK}/bin/mysqld --initialize --user=mysql --basedir=${MYSQL_LINK} --datadir=${MYSQL_LINK}/data

### copy MySQL boot scripts
cp ${MYSQL_LINK}/support-files/mysql.server /etc/init.d/mysqld
chmod +x /etc/init.d/mysqld
sed -i 's@^basedir=@basedir=/usr/local/mysql@g' /etc/init.d/mysqld
sed -i 's@^datadir=@datadir=/usr/local/mysql/data@g' /etc/init.d/mysqld

### MySQL take all command add system environment variable
cat << EOF >> /etc/profile
export PATH=$PATH:/usr/local/mysql/bin/
EOF
source /etc/profile

### MySQL start
/etc/init.d/mysqld start > /dev/null 2>&1
if [ $? -ne 0 ];then
   echo -e "${RED} MySQL start is failure,Please check MySQL error-log ${RES}"
   exit 1
fi

### grep MySQL initialize root password and modify root password is 123456
MYSQL_PASS=$(grep "A temporary password" /usr/local/mysql/logs/error.log | awk '{print $NF}')
${MYSQL_LINK}/bin/mysql --connect-expired-password -uroot   -p${MYSQL_PASS}   -e  "alter user 'root'@'localhost' identified by '123456'"

### setup MySQL service auto start
cat << EOF >> /etc/rc.local
/etc/init.d/mysqld start
EOF

chmod +x /etc/rc.local

### echo MySQL password
echo -e "\n\n###############################################\n"
echo "  MySQL root 密码 123456"
echo "  MySQL 服务启动命令  /etc/init.d/mysqld start"
echo "  MySQL 命令生效请执行命令 source /etc/profile"
echo -e "\n###############################################\n"

3、执行自动安装MySQL二进制软件包脚本

chmod +x /mnt/mysql_install.sh
cd /mnt/
sh mysql_install.sh

4、测试登录MySQL数据库

source /etc/profile
mysql -uroot -p123456

三、配置mysql01和mysql02相互主从同步（mysql01和mysql02都操作）

1、登录mysql01主机修改/etc/my.cnf配置文件

cat > /etc/my.cnf << EOF             
[client]
# 设置MySQL客户端连接端口
port=3306
# 设置MySQL客户端连接sock
socket=/usr/local/mysql/logs/mysql.sock
# 设置MySQL客户端编码
default-character-set=utf8mb4


[mysqld]
# 设置MySQL服务端TCP连接端口
port=3306
# 设置MySQL服务端SSL连接端口
mysqlx_port=33060
# 设置MySQL服务端编码
character-set-server=utf8mb4
# MySQL服务端安装目录
basedir=/usr/local/mysql
# MySQL服务端数据存放目录
datadir=/usr/local/mysql/data
# MySQL服务端socket文件地址
socket=/usr/local/mysql/logs/mysql.sock
# MySQL服务端mysqlx.socket文件地址
mysqlx_socket=/usr/local/mysql/logs/mysqlx.sock
# MySQL服务端PID文件地址
pid_file=/usr/local/mysql/logs/mysqld.pid
# MySQL服务端错误日志存储地址
log_error=/usr/local/mysql/logs/error.log
# 设置MySQL主从同步的server-id，每台MySQL设置的server-id不能相同
server-id=100
# 设置MySQL主从同步bin-log存放路径及名称
log-bin=/usr/local/mysql/logs/mysql-bin
# 设置MySQL主从同步方式，默认row
binlog_format=row
# 保留最近604800秒（7天）bin-log日志（默认秒为单位），默认保留最近30天
binlog_expire_logs_seconds=604800
# 设置主键自增起始值，两个master主库不能设置相同的值，否则容易引起主键自增值冲突
auto_increment_offset=1
# 控制主键自增长每次递增的量，用于防止Master主库与Master主库之间复制出现重复自增字段值，例如auto_increment_increment值与auto_increment_offset值组合使用，例如auto_increment_offset值等于1, auto_increment_increment值等于2，那么每次主键自增长值就是 1 3 5 7 9 11每次加2递增的主键值
auto_increment_increment=2
EOF

2、登录mysql02主机修改/etc/my.cnf配置文件

cat > /etc/my.cnf << EOF             
[client]
# 设置MySQL客户端连接端口
port=3306
# 设置MySQL客户端连接sock
socket=/usr/local/mysql/logs/mysql.sock
# 设置MySQL客户端编码
default-character-set=utf8mb4


[mysqld]
# 设置MySQL服务端TCP连接端口
port=3306
# 设置MySQL服务端SSL连接端口
mysqlx_port=33060
# 设置MySQL服务端编码
character-set-server=utf8mb4
# MySQL服务端安装目录
basedir=/usr/local/mysql
# MySQL服务端数据存放目录
datadir=/usr/local/mysql/data
# MySQL服务端socket文件地址
socket=/usr/local/mysql/logs/mysql.sock
# MySQL服务端mysqlx.socket文件地址
mysqlx_socket=/usr/local/mysql/logs/mysqlx.sock
# MySQL服务端PID文件地址
pid_file=/usr/local/mysql/logs/mysqld.pid
# MySQL服务端错误日志存储地址
log_error=/usr/local/mysql/logs/error.log
# 设置MySQL主从同步的server-id，每台MySQL设置的server-id不能相同
server-id=200
# 设置MySQL主从同步bin-log存放路径及名称
log-bin=/usr/local/mysql/logs/mysql-bin
# 设置MySQL主从同步方式，默认row
binlog_format=row
# 保留最近604800秒（7天）bin-log日志（默认秒为单位），默认保留最近30天
binlog_expire_logs_seconds=604800
# 设置主键自增起始值，两个master主库不能设置相同的值，否则容易引起主键自增值冲突
auto_increment_offset=2
# 控制主键自增长每次递增的量，用于防止Master主库与Master主库之间复制出现重复自增字段值，例如auto_increment_increment值与auto_increment_offset值组合使用，例如auto_increment_offset值等于2, auto_increment_increment值等于2，那么每次主键自增长值就是 2 4 6 8 10 12每次加2递增的主键值
auto_increment_increment=2
EOF

3、登录mysql01和mysql02分别重启MySQL数据库

/etc/init.d/mysqld restart

4、登录mysql01和mysql02分别创建MySQL主从同步用户

mysql -uroot -p123456
create user 'slaveuser'@'%' identified with mysql_native_password by '123456';
grant replication slave on *.* to 'slaveuser'@'%';
flush privileges;
select user,host from mysql.user;

5、登录mysql01查看master状态下的file文件和position位置点信息

注意：本教程安装的两个MySQL数据库都是初始化的数据库，没有任何生产数据

mysql> show master status\G;
*************************** 1. row ***************************
             File: mysql-bin.000001
         Position: 1951
     Binlog_Do_DB: 
 Binlog_Ignore_DB: 
Executed_Gtid_Set: 
1 row in set (0.00 sec)

6、登录mysql02配置从库同步mysql01主库信息

mysql -uroot -p123456

mysql> CHANGE MASTER TO MASTER_HOST='192.168.91.61', MASTER_PORT=3306,MASTER_USER='slaveuser',MASTER_PASSWORD='123456',MASTER_LOG_FILE='mysql-bin.000001',MASTER_LOG_POS=1951; 
Query OK, 0 rows affected, 9 warnings (0.01 sec)

mysql> start slave;
Query OK, 0 rows affected, 1 warning (0.00 sec)

### 主要看以下三个参数指标即可
mysql> show slave status\G;
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Seconds_Behind_Master: 0

###  Slave_IO_Running：Yes，这个表示I/O的线程状态，I/O线程负责从主库中读取Binlog日志，并将Binlog日志写入从库的中继日志中，状态为Yes表示I/O线程工作正常，否则异常。
###  Slave_SQL_Running：Yes，这个表示SQL的线程状态，SQL线程负责读取中继日志（relay-log）中的数据并转换为SQL语句应用到从数据库中，状态为Yes表示I/O线程工作正常，否则异常。
###  Seconds_Behind_Master：0，这个表示在复制过程中，从库比主库延迟的秒数。

### CHANGE MASTER TO 
### MASTER_HOST='192.168.91.61',             #<==主库的IP
### MASTER_PORT=3306,                      #<==主库的端口
### MASTER_USER='slaveuser',                 #<==主库创建主从同步用户
### MASTER_PASSWORD='123456',            #<==主库创建主从同步用户密码
### MASTER_LOG_FILE='mysql-bin.000001',     #<==主库show master status状态的file值
### MASTER_LOG_POS=1092;                  #<==主库show master status状态的position值

7、登录mysql02查看master状态下的file文件和position位置点信息

注意：本教程安装的两个MySQL数据库都是初始化的数据库，没有任何生产数据

mysql> show master status\G;
*************************** 1. row ***************************
             File: mysql-bin.000001
         Position: 1725
     Binlog_Do_DB: 
 Binlog_Ignore_DB: 
Executed_Gtid_Set: 
1 row in set (0.00 sec)

8、登录mysql01配置从库同步mysql02主库信息

mysql -uroot -p123456

mysql> CHANGE MASTER TO MASTER_HOST='192.168.91.62', MASTER_PORT=3306,MASTER_USER='slaveuser',MASTER_PASSWORD='123456',MASTER_LOG_FILE='mysql-bin.000001',MASTER_LOG_POS=1725; 
Query OK, 0 rows affected, 9 warnings (0.01 sec)

mysql> start slave;
Query OK, 0 rows affected, 1 warning (0.01 sec)

### 主要看以下三个参数指标即可
mysql> show slave status\G;
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Seconds_Behind_Master: 0

9、MySQL数据库双主测试

### 登录mysql01主机数据库创建一个测试用户testuser
[root@mysql01 ~]# mysql -uroot -p123456
mysql> create user testuser@'%' identified by '123456';
mysql> select user,host from mysql.user where user='testuser';
+----------+------+
| user     | host |
+----------+------+
| testuser | %    |
+----------+------+
1 row in set (0.00 sec)

### 登录mysql02主机数据库查看testuser测试用户是否同步创建
[root@mysql02 ~]# mysql -uroot -p123456
mysql> select user,host from mysql.user where user='testuser';
+----------+------+
| user     | host |
+----------+------+
| testuser | %    |
+----------+------+
1 row in set (0.00 sec)

### 登录mysql02主机数据库删除testuser测试用户
[root@mysql02 ~]# mysql -uroot -p123456
mysql> drop user testuser@'%';
Query OK, 0 rows affected (0.00 sec)
mysql> select user,host from mysql.user where user='testuser';
Empty set (0.00 sec)

### 登录mysql01主机数据库查看testuser测试用户是否同步删除
[root@mysql01 ~]# mysql -uroot -p123456
mysql> select user,host from mysql.user where user='testuser';
Empty set (0.00 sec)

四、登录mysql01和mysql02安装配置keepalived服务

1、登录mysql01安装配置keepalived服务

yum -y install keepalived
mv /etc/keepalived/keepalived.conf /tmp/

### 修改keepalived服务配置文件，根据实际情况修改IP地址、网卡名称、state参数值名称要修改成MASTER、priority参数值越大，优先级就越高，master优先级要高于backup
cat > /etc/keepalived/keepalived.conf << 'EOF'
! Configuration File for keepalived
global_defs {
   script_user root
   notification_email {
      lishi666@qq.com
   }
   notification_email_from xiaoming@qq.com
   smtp_server mail.qq.com
   smtp_connect_timeout 30
   router_id LVS_MASTER
   enable_script_security
}

vrrp_script check_mysql_port {
   script "/data/scripts/check.sh"
   interval 1
   weight -5
}

vrrp_instance VI_1 {
   state MASTER
   interface ens33
   virtual_router_id 92
   priority 100
   advert_int 1

   notify_master "/data/scripts/notify.sh master"
   notify_slave "/data/scripts/notify.sh backup"
   notify_fault "/data/scripts/notify.sh fault"

   unicast_src_ip 192.168.91.61
   unicast_peer {
       192.168.91.62
   }

   authentication {
       auth_type PASS
       auth_pass 123456
   }

   virtual_ipaddress {
      192.168.91.100
   }

   track_script {
      check_mysql_port
   }
}
EOF

### 配置SMTP发送邮件功能，设置个人的外网邮箱账号，此邮件账号主要用来发送邮件使用
cat > /etc/mail.rc << EOF
set from=xiaoming@qq.com
set smtp=mail.qq.com
set smtp-auth-user=xiaoming@qq.com
set smtp-auth-password=abc123456
set smtp-auth=login
EOF

### 创建keepalived服务检测MySQL状态是否正常的脚本
mkdir -p /data/scripts
cat > /data/scripts/check.sh << 'EOF'
#!/bin/bash
source /etc/profile
mysql_pid=`ps -ef|grep mysql |grep -v grep | awk '{print $2}' | wc -l`
if [ ${mysql_pid} -eq 0 ];then
systemctl stop keepalived
fi
EOF

### 创建keepalived故障邮件通知脚本，根据实际情况修改IP、主机名称、收件人邮件地址
cat > /data/scripts/notify.sh << 'EOF'
#!/bin/bash
#接收者邮箱，多个以空格分隔
contact=(lishi666@qq.com)
#本机ip
HOST_IP=192.168.91.61
HOST_NAME=mysql01
notify() {
    #邮件主题
    mailsubject="MySQL Keepalived负载均衡VIP地址发生了转移"
    #邮件正文
    description="事件描述：${HOST_IP}  keepalived changed to be $1"
    datebody="发生时间：$(date +'%F %T')"
    hostnamebody="主机名称：${HOST_IP}"
    ipbody="主机IP： ${HOST_NAME}"
    for receiver in ${contact[*]}
    do
        #发送邮件
        echo -e "${description} ${hostbody} \n ${datebody} \n ${hostnamebody} \n ${ipbody}" | mail -s "$mailsubject" $receiver
    done
}
case $1 in
master)
    notify master
    ;;
backup)
    notify backup
    ;;
fault)
    notify fault
    ;;
*)
    echo "Usage:{master|backup|fault}"
    exit 1
    ;;
esac
EOF

chmod +x /data/scripts/*.sh

2、登录mysql02安装配置keepalived服务

yum -y install keepalived
mv /etc/keepalived/keepalived.conf /tmp/

### 修改keepalived服务配置文件，根据实际情况修改IP地址、网卡名称、state参数值名称要修改成BACKUP、priority参数值越大，优先级就越高，backup优先级要低于master
cat > /etc/keepalived/keepalived.conf << 'EOF'
! Configuration File for keepalived
global_defs {
   script_user root
   notification_email {
      lishi666@qq.com
   }
   notification_email_from xiaoming@qq.com
   smtp_server mail.qq.com
   smtp_connect_timeout 30
   router_id LVS_MASTER
   enable_script_security
}

vrrp_script check_mysql_port {
   script "/data/scripts/check.sh"
   interval 1
   weight -5
}

vrrp_instance VI_1 {
   state BACKUP
   interface ens33
   virtual_router_id 92
   priority 60
   advert_int 1

   notify_master "/data/scripts/notify.sh master"
   notify_slave "/data/scripts/notify.sh backup"
   notify_fault "/data/scripts/notify.sh fault"

   unicast_src_ip 192.168.91.62
   unicast_peer {
       192.168.91.61
   }

   authentication {
       auth_type PASS
       auth_pass 123456
   }

   virtual_ipaddress {
      192.168.91.100
   }

   track_script {
      check_mysql_port
   }
}
EOF

### 配置SMTP发送邮件功能，设置个人的外网邮箱账号，此邮件账号主要用来发送邮件使用
cat > /etc/mail.rc << EOF
set from=xiaoming@qq.com
set smtp=mail.qq.com
set smtp-auth-user=xiaoming@qq.com
set smtp-auth-password=abc123456
set smtp-auth=login
EOF

### 创建keepalived服务检测MySQL状态是否正常的脚本
mkdir -p /data/scripts
cat > /data/scripts/check.sh << 'EOF'
#!/bin/bash
source /etc/profile
mysql_pid=`ps -ef|grep mysql |grep -v grep | awk '{print $2}' | wc -l`
if [ ${mysql_pid} -eq 0 ];then
systemctl stop keepalived
fi
EOF

### 创建keepalived故障邮件通知脚本，根据实际情况修改IP、主机名称、收件人邮件地址
cat > /data/scripts/notify.sh << 'EOF'
#!/bin/bash
#接收者邮箱，多个以空格分隔
contact=(lishi666@qq.com)
#本机ip
HOST_IP=192.168.91.62
HOST_NAME=mysql02
notify() {
    #邮件主题
    mailsubject="MySQL Keepalived负载均衡VIP地址发生了转移"
    #邮件正文
    description="事件描述：${HOST_IP}  keepalived changed to be $1"
    datebody="发生时间：$(date +'%F %T')"
    hostnamebody="主机名称：${HOST_IP}"
    ipbody="主机IP： ${HOST_NAME}"
    for receiver in ${contact[*]}
    do
        #发送邮件
        echo -e "${description} ${hostbody} \n ${datebody} \n ${hostnamebody} \n ${ipbody}" | mail -s "$mailsubject" $receiver
    done
}
case $1 in
master)
    notify master
    ;;
backup)
    notify backup
    ;;
fault)
    notify fault
    ;;
*)
    echo "Usage:{master|backup|fault}"
    exit 1
    ;;
esac
EOF

chmod +x /data/scripts/*.sh

3、登录mysql01和mysql02启动keepalived服务

### 先登录mysql01主机启动keepalived服务
systemctl start keepalived
systemctl status keepalived
ip a | grep 192.168.91.100

### 再登录mysql02主机启动keepalived服务
systemctl start keepalived
systemctl status keepalived

总结

以上为个人经验，希望能给大家一个参考，也希望大家多多支持脚本之家。

您可能感兴趣的文章:
阅读全文