MySql主从配置(主从热备份)

末蓝、 2022-01-16 04:15 262阅读 0赞

[2019独角兽企业重金招聘Python工程师标准>>> ][2019_Python_] ![hot3.png][]

## 环境说明 ##

系统：centos7.5
    软件版本：mysql-5.7.23-linux-glibc2.12-x86_64.tar.gz
    安装目录：/usr/local/mysql
    数据库目录：/data/mysql
    数据库root密码：hc123456
    A数据库：192.168.2.72 主
    B数据库：192.168.2.73 从
    
    数据库同步账号: sync
    数据库sync密码: pcpaeyphmp

## 安装MySql ##

> 两台分别都安装

### 创建用户,组 ###

> 创建mysql组指定组id为1200，创建mysql用户指定用户id为1200默认组mysql

groupadd -g 1200 mysql
    useradd -r -g mysql -u 1200 -s /sbin/nologin mysql

### 创建数据目录 ###

> mysql数据库数据存储目录

datadir=/data/mysql         # 数据库数据存储目录
    mkdir -p $datadir
    basedir=/usr/local/mysql    # 数据库安装目录

### 关闭Selinux ###

setenforce 0
    sed -i 's/SELINUX=enforcing/SELINUX=disabled/' /etc/selinux/config

### 安装 jemalloc ###

> 配置软件安装源,安装jemalloc适合多线程下内存分配管理,减少内存碎片

rm -rf /etc/yum.repos.d/*
    curl -so /etc/yum.repos.d/epel-7.repo http://mirrors.aliyun.com/repo/epel-7.repo
    curl -so /etc/yum.repos.d/Centos-7.repo http://mirrors.aliyun.com/repo/Centos-7.repo
    sed -i '/aliyuncs.com/d' /etc/yum.repos.d/Centos-7.repo /etc/yum.repos.d/epel-7.repo
    yum install -y jemalloc-devel

### [下载软件][Link 1],解压 ###

curl -OL http://mirrors.ustc.edu.cn/mysql-ftp/Downloads/MySQL-5.7/mysql-5.7.23-linux-glibc2.12-x86_64.tar.gz --progress
    tar xvf mysql-5.7.23-linux-glibc2.12-x86_64.tar.gz
    mv mysql-5.7.23-linux-glibc2.12-x86_64/ $basedir

### 配置服务 ###

cp $basedir/support-files/mysql.server /etc/init.d/mysqld
    sed -i "s@^basedir=.*@basedir=$basedir@" /etc/init.d/mysqld
    sed -i "s@^datadir=.*@datadir=$datadir@" /etc/init.d/mysqld
    chmod +x /etc/init.d/mysqld
    chkconfig --add mysqld
    chkconfig mysqld on

### mysql配置文件 ###

cat << EOF >/etc/my.cnf
    [client]
    port = 3306
    socket = /tmp/mysql.sock
    default-character-set = utf8mb4
    
    [mysql]
    prompt="MySQL [\\d]> "
    no-auto-rehash
    
    [mysqld]
    skip-ssl
    port = 3306
    user = mysql
    server-id = 1
    bind-address = 0.0.0.0
    log_timestamps = SYSTEM
    socket = /tmp/mysql.sock
    
    basedir = $basedir
    datadir = $datadir
    character-set-server = utf8mb4
    pid-file = $datadir/mysql.pid
    init-connect = 'SET NAMES utf8mb4'
    
    back_log = 300
    #skip-networking
    skip-name-resolve
    
    max_connections = 1000
    max_connect_errors = 6000
    open_files_limit = 65535
    table_open_cache = 128
    max_allowed_packet = 500M
    binlog_cache_size = 1M
    max_heap_table_size = 8M
    tmp_table_size = 16M
    
    read_buffer_size = 2M
    read_rnd_buffer_size = 8M
    sort_buffer_size = 8M
    join_buffer_size = 8M
    key_buffer_size = 4M
    
    thread_cache_size = 8
    
    query_cache_type = 1
    query_cache_size = 8M
    query_cache_limit = 2M
    
    ft_min_word_len = 4
    
    log_bin = mysql-bin
    binlog_format = mixed
    expire_logs_days = 7
    
    slow_query_log = 1
    long_query_time = 1
    log_error = $datadir/mysql-error.log
    slow_query_log_file = $datadir/mysql-slow.log
    
    performance_schema = 0
    explicit_defaults_for_timestamp
    
    #lower_case_table_names = 1
    
    skip-external-locking
    
    default_storage_engine = InnoDB
    #default-storage-engine = MyISAM
    innodb_file_per_table = 1
    innodb_open_files = 500
    innodb_buffer_pool_size = 64M
    innodb_write_io_threads = 4
    innodb_read_io_threads = 4
    innodb_thread_concurrency = 0
    innodb_purge_threads = 1
    innodb_flush_log_at_trx_commit = 2
    innodb_log_buffer_size = 2M
    innodb_log_file_size = 32M
    innodb_log_files_in_group = 3
    innodb_max_dirty_pages_pct = 90
    innodb_lock_wait_timeout = 120
    
    bulk_insert_buffer_size = 8M
    myisam_sort_buffer_size = 8M
    myisam_max_sort_file_size = 10M
    myisam_repair_threads = 1
    
    interactive_timeout = 28800
    wait_timeout = 28800
    
    [mysqldump]
    quick
    max_allowed_packet = 500M
    
    [myisamchk]
    key_buffer_size = 8M
    sort_buffer_size = 8M
    read_buffer = 4M
    write_buffer = 4M
    EOF

### 数据库配置优化 ###

cp /etc/my.cnf{,.bak}
    Mem=`free -m | awk '/Mem:/{print $2}'`
    sed -i "s@max_connections.*@max_connections = $((${Mem}/3))@" /etc/my.cnf
    if [ ${Mem} -gt 1500 -a ${Mem} -le 2500 ]; then
        #  1500MB < 实际内存 <= 2500MB
        sed -i 's@^thread_cache_size.*@thread_cache_size = 16@' /etc/my.cnf
        sed -i 's@^query_cache_size.*@query_cache_size = 16M@' /etc/my.cnf
        sed -i 's@^myisam_sort_buffer_size.*@myisam_sort_buffer_size = 16M@' /etc/my.cnf
        sed -i 's@^key_buffer_size.*@key_buffer_size = 16M@' /etc/my.cnf
        sed -i 's@^innodb_buffer_pool_size.*@innodb_buffer_pool_size = 128M@' /etc/my.cnf
        sed -i 's@^tmp_table_size.*@tmp_table_size = 32M@' /etc/my.cnf
        sed -i 's@^table_open_cache.*@table_open_cache = 256@' /etc/my.cnf
    elif [ ${Mem} -gt 2500 -a ${Mem} -le 3500 ]; then
        #  2500MB < 实际内存 <= 3500MB
        sed -i 's@^thread_cache_size.*@thread_cache_size = 32@' /etc/my.cnf
        sed -i 's@^query_cache_size.*@query_cache_size = 32M@' /etc/my.cnf
        sed -i 's@^myisam_sort_buffer_size.*@myisam_sort_buffer_size = 32M@' /etc/my.cnf
        sed -i 's@^key_buffer_size.*@key_buffer_size = 64M@' /etc/my.cnf
        sed -i 's@^innodb_buffer_pool_size.*@innodb_buffer_pool_size = 512M@' /etc/my.cnf
        sed -i 's@^tmp_table_size.*@tmp_table_size = 64M@' /etc/my.cnf
        sed -i 's@^table_open_cache.*@table_open_cache = 512@' /etc/my.cnf
    elif [ ${Mem} -gt 3500 ]; then
        #  3500MB < 实际内存
        sed -i 's@^thread_cache_size.*@thread_cache_size = 64@' /etc/my.cnf
        sed -i 's@^query_cache_size.*@query_cache_size = 64M@' /etc/my.cnf
        sed -i 's@^myisam_sort_buffer_size.*@myisam_sort_buffer_size = 64M@' /etc/my.cnf
        sed -i 's@^key_buffer_size.*@key_buffer_size = 256M@' /etc/my.cnf
        sed -i 's@^innodb_buffer_pool_size.*@innodb_buffer_pool_size = 1024M@' /etc/my.cnf
        sed -i 's@^tmp_table_size.*@tmp_table_size = 128M@' /etc/my.cnf
        sed -i 's@^table_open_cache.*@table_open_cache = 1024@' /etc/my.cnf
    fi

### 配置mysql库文件 ###

rm -rf /etc/ld.so.conf.d/mariadb-x86_64.conf
    echo "$basedir/lib" > /etc/ld.so.conf.d/mysql.conf
    ldconfig

### 初始化数据库 ###

> 添加`libjemalloc`模块,初始化数据库,启动`mysql`服务

sed -i 's@executing mysqld_safe@executing mysqld_safe\nexport LD_PRELOAD=/usr/lib64/libjemalloc.so@' $basedir/bin/mysqld_safe
    $basedir/bin/mysqld --initialize-insecure --user=mysql --basedir=$basedir --datadir=$datadir
    chmod 600 /etc/my.cnf
    chown mysql.mysql -R $datadir
    systemctl start mysqld
    lsof | grep jemalloc

### 添加环境变量 ###

echo -e "\n# mysqld\nexport PATH=\$PATH:$basedir/bin" >> ~/.bashrc
    . ~/.bashrc

### 初始化root密码, 权限 ###

> mysql授权 127.0.0.1,local 表示仅本机, % 表示所有主机

RootPass=hc123456       # 数据库root密码
    mysql -e "grant all privileges on *.* to root@'127.0.0.1' identified by \"${RootPass}\" with grant option;"
    mysql -e "grant all privileges on *.* to root@'localhost' identified by \"${RootPass}\" with grant option;"
    mysql -uroot -p${RootPass} -e "reset master;"

### 开启root远程登录权限 ###

mysql -uroot -p${RootPass} -e "grant all privileges on *.* to root@'%' identified by \"${RootPass}\" with grant option;"
    # 查看数据库用户权限
    mysql -uroot -p${RootPass} -e "select user,host,authentication_string from mysql.user;"

### 配置防火墙 ###

firewall-cmd --zone=public --add-port=3306/tcp --permanent
    firewall-cmd --reload

## A数据库配置 ##

### 开启二进制日志 ###

> 1.开启binlog(数据库二进制日志),设置server-id,重启mysql服务

cp /etc/my.cnf{,.`date +%F`}
    sed -i '14a log-bin = mysql-bin' /etc/my.cnf
    sed -i 's/server-id.*/server-id = 1/g' /etc/my.cnf
    sed -i '18a log-bin-index = master-bin.index' /etc/my.cnf
    systemctl restart mysqld

### 创建同步账户,授权 ###

> 2.创建同步数据的用户,授权允许192.168.2.0/24网络使用sync用户登录

mysql -uroot -p${RootPass}
    create user sync;
    grant replication slave on *.* to 'sync'@'192.168.2.%' identified by 'pcpaeyphmp';
    flush privileges;
    show master status;
    exit
    
    # MySQL [(none)]> show master status;
    # 记下 binlog文件的position（偏移）和File（日志文件）的值)
    +------------------+----------+--------------+------------------+-------------------+
    | File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
    +------------------+----------+--------------+------------------+-------------------+
    | mysql-bin.000002 |      797 |              |                  |                   |
    +------------------+----------+--------------+------------------+-------------------+

## B数据库配置 ##

> 1.配置从库只允许来自服务器线程或具有SUPER权限的数据库用户进行更新(root,sync),开启binlog(数据库二进制日志),设置server-id,重启mysql服务

cp /etc/my.cnf{,.`date +%F`}
    sed -i '11a read-only' /etc/my.cnf
    sed -i '15a log-bin = mysql-bin' /etc/my.cnf
    sed -i 's/server-id.*/server-id = 2/g' /etc/my.cnf
    sed -i '19a log-bin-index = master-bin.index' /etc/my.cnf
    systemctl restart mysqld

### 配置连接A数据库 ###

mysql -uroot -p${RootPass}
    change master to master_host='192.168.2.72',  # A数据库 IP或主机名(需解析通)
    master_port=3306,                             # A数据库端口号
    master_user='sync',                           # 同步账号
    master_password='pcpaeyphmp',                 # 同步账号的密码
    master_log_file='mysql-bin.000002',           # A数据库执行 show master status; 获取的 File 值
    master_log_pos=797;                           # A数据库执行 show master status; 获取的 Position 值
    start slave;                                  # 启动slave
    show slave status\G;                          # 查看同步状态
    exit
    
    # MySQL [(none)]> show slave status\G;
    *************************** 1. row ***************************
                   Slave_IO_State: Waiting for master to send event
                      Master_Host: 192.168.2.72
                      Master_User: sync
                      Master_Port: 3306
                    Connect_Retry: 60
                  Master_Log_File: mysql-bin.000002
              Read_Master_Log_Pos: 797
                   Relay_Log_File: localhost-relay-bin.000002
                    Relay_Log_Pos: 320
            Relay_Master_Log_File: mysql-bin.000002
                 Slave_IO_Running: Yes
                Slave_SQL_Running: Yes
               ............................
    
    # 保证以下两项状态为 Yes 连接成功
    Slave_IO_Running: Yes
    Slave_SQL_Running: Yes

## 验证 ##

> A创建数据库

> B查看数据库

## 排错 ##

Slave_IO_Running:     # 状态不为Yes
    
    1.数据库A与数据库B之间网络是否通畅
    2.同步账号的用户权限,及是否允许数据库B登录
    3.查看两端server-id(不能相同) 使用mysql命令查看 show variables like 'server_id'; 此配置项在my.cnf
    4.配置从连接主时 binlog 文件的 position（偏移）和 File（日志文件）的值) 是否正确

转载于:https://my.oschina.net/yx571304/blog/3013558

[2019_Python_]: https://my.oschina.net/u/2663968/blog/3061697
[hot3.png]: /images/20220114/a26e052dc1ee4ff89d02e3788bb4a34b.png
[Link 1]: http://mirrors.ustc.edu.cn/mysql-ftp/Downloads/