MySQL双主搭建-5.7.35

上传并安装MySQL 5.7.35

（172.25.0.19与172.25.0.20均部署安装并启动）

[root@QYWLAQ_VMC4234 ~]# hostnamectlStatic hostname: QYWLAQ_VMC4234Icon name: computer-vmChassis: vmMachine ID: cd3605d12efd430fb723eb507cf5ce3bBoot ID: 00f929e5510944efb40d53ef55d92a49Virtualization: kvmOperating System: CentOS Linux 7 (Core)CPE OS Name: cpe:/o:centos:centos:7Kernel: Linux 3.10.0-1160.el7.x86_64Architecture: x86-64[root@QYWLAQ_VMC4234 ~]# ll
-rw-r--r--  1 citc unicom  26658592 12月 25 17:02 mysql-community-client-5.7.35-1.el7.x86_64.rpm
-rw-r--r--  1 citc unicom    317800 12月 25 17:03 mysql-community-common-5.7.35-1.el7.x86_64.rpm
-rw-r--r--  1 citc unicom   2473348 12月 25 17:03 mysql-community-libs-5.7.35-1.el7.x86_64.rpm
-rw-r--r--  1 citc unicom   1263816 12月 26 14:35 mysql-community-libs-compat-5.7.35-1.el7.x86_64.rpm
-rw-r--r--  1 citc unicom 182213816 12月 25 17:05 mysql-community-server-5.7.35-1.el7.x86_64.rpm# 安装rpm包
[root@QYWLAQ_VMC4234 ~]# yum localinstall -y *.rpm# 启动并设置开启自启
[root@QYWLAQ_VMC4234 ~]# systemctl enable --now mysqld[root@QYWLAQ_VMC4234 citc]# systemctl status mysqld
● mysqld.service - MySQL ServerLoaded: loaded (/usr/lib/systemd/system/mysqld.service; enabled; vendor preset: disabled)Active: active (running) since 三 2025-02-26 12:24:03 CST; 4min 26s agoDocs: man:mysqld(8)http://dev.mysql.com/doc/refman/en/using-systemd.htmlProcess: 8441 ExecStart=/usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid $MYSQLD_OPTS (code=exited, status=0/SUCCESS)Process: 8374 ExecStartPre=/usr/bin/mysqld_pre_systemd (code=exited, status=0/SUCCESS)Main PID: 8444 (mysqld)Tasks: 27Memory: 289.2MCGroup: /system.slice/mysqld.service└─8444 /usr/sbin/mysqld --daemonize --pid-file=/var/run/mysqld/mysqld.pid2月 26 12:23:57 QYWLAQ_VMC4234 systemd[1]: Starting MySQL Server...
2月 26 12:24:03 QYWLAQ_VMC4234 systemd[1]: Started MySQL Server.# 获取初始密码
[root@QYWLAQ_VMC4234 citc]# sudo grep 'temporary password' /var/log/mysqld.log
2025-02-26T04:23:59.794639Z 1 [Note] A temporary password is generated for root@localhost: IlM3/)Ya6VMH# 登录
[root@QYWLAQ_VMC4234 citc]# mysql -u root -p'IlM3/)Ya6VMH'
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 2
Server version: 5.7.35Copyright (c) 2000, 2021, Oracle and/or its affiliates.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> ALTER USER 'root'@'localhost' IDENTIFIED BY '8th3xY]:NA'; -- 修改root密码
Query OK, 0 rows affected (0.00 sec)mysql> FLUSH PRIVILEGES; -- 刷新权限以使修改立即生效
Query OK, 0 rows affected (0.01 sec)

双主复制的配置

实例一：172.25.0.19：

# 此配置文件中追加下述配置
[root@QYWLAQ_VMC4234 ~]# vi /etc/my.cnf[mysqld]
# 基本配置
server-id = 1                     # 每个实例的 server-id 必须唯一
log_bin = /var/log/mysql/mysql-bin.log  # 启用二进制日志
binlog_format = ROW               # 推荐使用 ROW 格式
expire_logs_days = 7              # 自动清理 7 天前的日志
max_binlog_size = 100M            # 每个二进制日志文件的最大大小# 双主复制配置
log_slave_updates = 1             # 从库记录二进制日志（必须启用）
auto_increment_increment = 2      # 自增步长
auto_increment_offset = 1         # 自增起始值（实例 1 为 1，实例 2 为 2）# 复制过滤（可选）
replicate-do-db = my_database     # 只复制指定的数据库
replicate-ignore-db = mysql       # 忽略系统库# 其他配置
bind-address = 0.0.0.0            # 允许远程连接

重启MySQL

[root@QYWLAQ_VMC4234 ~]# systemctl restart mysqld

实例二：172.25.0.20：

# 此配置文件中追加下述配置
[root@QYWLAQ_VMC1091 ~]# vi /etc/my.cnf[mysqld]
# 基本配置
server-id = 2                     # 每个实例的 server-id 必须唯一
log_bin = /var/log/mysql/mysql-bin.log  # 启用二进制日志
binlog_format = ROW               # 推荐使用 ROW 格式
expire_logs_days = 7              # 自动清理 7 天前的日志
max_binlog_size = 100M            # 每个二进制日志文件的最大大小# 双主复制配置
log_slave_updates = 1             # 从库记录二进制日志（必须启用）
auto_increment_increment = 2      # 自增步长
auto_increment_offset = 2         # 自增起始值（实例 1 为 1，实例 2 为 2）# 复制过滤（可选）
replicate-do-db = my_database     # 只复制指定的数据库
replicate-ignore-db = mysql       # 忽略系统库# 其他配置
bind-address = 0.0.0.0            # 允许远程连接

重启MySQL

[root@QYWLAQ_VMC1091 ~]# systemctl restart mysqld

配置复制用户

在每个 MySQL 实例上创建一个用于复制的用户。

在实例 1 （172.25.0.19）上执行：

mysql> CREATE USER 'replication'@'172.25.0.20' IDENTIFIED BY '@2X0wZY/rq';
Query OK, 0 rows affected (0.01 sec)mysql> GRANT REPLICATION SLAVE ON *.* TO 'replication'@'172.25.0.20';
Query OK, 0 rows affected (0.00 sec)mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.01 sec)

查询用户

mysql> SELECT User, Host FROM mysql.user;
+---------------+-------------+
| User          | Host        |
+---------------+-------------+
| replication   | 172.25.0.20 |
| mysql.session | localhost   |
| mysql.sys     | localhost   |
| root          | localhost   |
+---------------+-------------+
4 rows in set (0.00 sec)

在实例 2 （172.25.0.20）上执行：

mysql> CREATE USER 'replication'@'172.25.0.19' IDENTIFIED BY '@2X0wZY/rq';
Query OK, 0 rows affected (0.00 sec)mysql> GRANT REPLICATION SLAVE ON *.* TO 'replication'@'172.25.0.19';
Query OK, 0 rows affected (0.00 sec)mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.00 sec)

查询用户

mysql> SELECT User, Host FROM mysql.user;
+---------------+-------------+
| User          | Host        |
+---------------+-------------+
| replication   | 172.25.0.19 |
| mysql.session | localhost   |
| mysql.sys     | localhost   |
| root          | localhost   |
+---------------+-------------+
4 rows in set (0.00 sec)

配置主从复制

在每个实例上配置对方为主库。

查看实例 2 节点状态：

mysql> SHOW MASTER STATUS;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000002 |      964 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

在实例 1 上执行：

CHANGE MASTER TOMASTER_HOST='172.25.0.20',MASTER_USER='replication',MASTER_PASSWORD='@2X0wZY/rq',MASTER_LOG_FILE='mysql-bin.000002',     -- 替换为实例 2 的当前 binlog 文件MASTER_LOG_POS=1784;                     -- 替换为实例 2 的当前 binlog 位置
START SLAVE;

查看实例 1 节点状态：

mysql> SHOW MASTER STATUS;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000002 |      964 |              |                  |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

在实例 2 上执行：

CHANGE MASTER TOMASTER_HOST='172.25.0.19',MASTER_USER='replication',MASTER_PASSWORD='@2X0wZY/rq',MASTER_LOG_FILE='mysql-bin.000002',     -- 替换为实例 1 的当前 binlog 文件MASTER_LOG_POS=1784;                     -- 替换为实例 1 的当前 binlog 位置
START SLAVE;

---

验证复制状态

在每个实例上执行以下命令，检查复制状态：

SHOW SLAVE STATUS\G;

确保以下字段的值为 Yes：

• Slave_IO_Running
• Slave_SQL_Running

测试双主复制

在 Server A 上操作：

创建测试数据库和表：

CREATE DATABASE test_db;
USE test_db;
CREATE TABLE test_table (id INT AUTO_INCREMENT PRIMARY KEY,name VARCHAR(50)
) ENGINE=InnoDB;

插入数据：

INSERT INTO test_table (name) VALUES ('Server A Data');

在 Server B 上操作：

检查数据是否同步：

USE test_db;
SELECT * FROM test_table;

应该能看到 Server A Data。

插入数据：

INSERT INTO test_table (name) VALUES ('Server B Data');

回到 Server A 上操作：

检查数据是否同步：

USE test_db;
SELECT * FROM test_table;

table (name) VALUES (‘Server A Data’);

### 在 Server B 上操作：**检查数据是否同步**：

USE test_db;
SELECT * FROM test_table;

应该能看到 `Server A Data`。**插入数据**：

INSERT INTO test_table (name) VALUES (‘Server B Data’);

### 回到 Server A 上操作：**检查数据是否同步**：

USE test_db;
SELECT * FROM test_table;

应该能看到 `Server B Data`。