【史上最細教程】服務器MySQL數據庫完成主從復制

文章目錄

MySQL完成主從復制教程
- 準備：
- 原理：
- 步驟：
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MySQL完成主從復制教程

主從復制（也稱 AB 復制）就是將一個服務器（主服務器）的數據復制到一個或多個MySQL數據庫服務器（從服務器）中。

可以根據配置，指定復制哪個庫哪個表數據。

可以想到復制是通過異步的。

準備：

2臺版本一致的服務器數據庫，一臺作為主庫、一臺作為從庫

（我的兩個數據庫版本：5.7）

一臺服務器搭建2個數據庫實例教程：http://t.csdnimg.cn/aaErM

原理：

主庫一旦變更數據，就會寫入二進制日志文件（Binary log），從庫IO線程（ I/O thread）連接到主庫，讀取二進制日志文件內容并寫入自己的中繼日志文件（Realy log），然后從庫 SQL thread 定時檢查中繼日志（Realy log），發現有更新的內容就自己的庫執行一遍。

從服務器都會copy主服務器二進制日志的全部內容到副本，然后從服務器設備負責決定應該執行副本中的哪些語句。

步驟：

主庫配置my.cnf文件指定唯一server-id

[mysqld]
## 同一局域網內注意要唯一
server-id=100  
## 開啟二進制日志功能，可以隨便取（關鍵）
log-bin=mysql-bin
## 復制過濾：不需要備份的數據庫，不輸出（mysql庫一般不同步）
binlog-ignore-db=mysql
## 為每個session 分配的內存，在事務過程中用來存儲二進制日志的緩存
binlog_cache_size=1M
## 主從復制的格式（mixed,statement,row，默認格式是statement）
binlog_format=mixed

從庫配置my.cnf文件指定唯一server-id

[mysqld]
## 設置server_id,注意要唯一
server-id=102
## 開啟二進制日志功能，以備Slave作為其它Slave的Master時使用
log-bin=mysql-slave-bin
## relay_log配置中繼日志
relay_log=edu-mysql-relay-bin
##復制過濾：不需要備份的數據庫，不輸出（mysql庫一般不同步）
binlog-ignore-db=mysql
## 如果需要同步函數或者存儲過程
log_bin_trust_function_creators=true
## 為每個session 分配的內存，在事務過程中用來存儲二進制日志的緩存
binlog_cache_size=1M
## 主從復制的格式（mixed,statement,row，默認格式是statement）
binlog_format=mixed
## 跳過主從復制中遇到的所有錯誤或指定類型的錯誤，避免slave端復制中斷。
## 如：1062錯誤是指一些主鍵重復，1032錯誤是因為主從數據庫數據不一致
slave_skip_errors=1062

重啟3306、3307服務，使配置生效

# 查看mysql 3306、3307進程
root@songdanminserver:[/usr/local/mysql/3306/run]ps -ef | grep mysqld
root      8568 25795  0 13:40 pts/0    00:00:00 grep --color=auto mysqld
mysql    30201     1  0 Nov10 ?        00:07:13 /usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/3306/my.cnf --user=mysql
mysql    30473     1  0 Nov10 ?        00:07:46 /usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/3307/my.cnf --user=mysql
# 停止3306、3307進程服務
root@songdanminserver:[/usr/local/mysql/3306/run]kill 30201
root@songdanminserver:[/usr/local/mysql/3306/run]kill 30473
# 查看mysql進程
root@songdanminserver:[/usr/local/mysql/3306/run]ps -ef | grep mysqld
root      8614 25795  0 13:41 pts/0    00:00:00 grep --color=auto mysqld
# 查看端口占用情況是否沒有3306、3307
root@songdanminserver:[/usr/local/mysql/3306/run]netstat -ntl
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State      
tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN     
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN     
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN     
tcp6       0      0 :::111                  :::*                    LISTEN     
tcp6       0      0 :::8080                 :::*                    LISTEN     
tcp6       0      0 ::1:25                  :::*                    LISTEN     
tcp6       0      0 127.0.0.1:8005          :::*                    LISTEN     
# 重新啟動3306、3307
root@songdanminserver:[/usr/local/mysql/3306]nohup /usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/3306/my.cnf --user=mysql &
[1] 9413
root@songdanminserver:[/usr/local/mysql/3306]nohup: ignoring input and appending output to ‘nohup.out’
^C
root@songdanminserver:[/usr/local/mysql/3307]nohup /usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/3307/my.cnf --user=mysql &
[2] 9457
root@songdanminserver:[/usr/local/mysql/3307]nohup: ignoring input and appending output to ‘nohup.out’
^C
root@songdanminserver:[/usr/local/mysql/3306]# 查看mysql 3306、3307進程
root@songdanminserver:[/usr/local/mysql/3307]ps -ef | grep mysqld
mysql     9413 25795  0 13:52 pts/0    00:00:00 /usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/3306/my.cnf --user=mysql
mysql     9559 25795  1 13:54 pts/0    00:00:00 /usr/local/mysql/bin/mysqld --defaults-file=/usr/local/mysql/3307/my.cnf --user=mysql
root      9608 25795  0 13:54 pts/0    00:00:00 grep --color=auto mysqld

登錄主庫，授予從庫連接主庫，并復制主庫數據的權限，刷新權限生效

# 登錄主庫3306
root@songdanminserver:[/usr/local/mysql/3306]mysql -uroot -h127.0.0.1 -p -P3306
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.7.36-log MySQL Community Server (GPL)Copyright (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.# 授予從庫3307的root用戶在指定從庫ip上從主庫復制所有庫、所有表數據的權限
mysql> grant replication slave, replication client on *.* to 'root'@'你的從庫服務器ip' identified by '你的從庫root用戶密碼';
Query OK, 0 rows affected, 1 warning (0.00 sec)# 刷新權限
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)# 查看MySQL現在有哪些用戶及對應的IP權限，可以看到你剛授權的從庫user,host
mysql> select user,host from mysql.user;
+---------------+--------------+
| user          | host         |
+---------------+--------------+
| root          | %            |
| root          | 121.41.59.91 |
| mysql.session | localhost    |
| mysql.sys     | localhost    |
+---------------+--------------+
4 rows in set (0.00 sec)# 查看主庫3306的binlog文件名和位置
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000003 |      612 |              | mysql            |                   |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

登錄從庫，連接主庫，指定主庫ip、主庫為從庫連接所創建的用戶、密碼、從庫從主庫哪個二進制文件的哪里開始讀取數據等

# 登錄從庫3307
root@songdanminserver:[/usr/local/mysql/3306]mysql -uroot -h127.0.0.1 -p -P3307
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.36-log MySQL Community Server (GPL)Copyright (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.# 配置連接主庫3306
# change master to master_host='主庫服務器ip', master_user='root(上一步主庫授權從庫能進行復制的用戶)', master_password='123456(上一步主庫授權從庫能進行復制的密碼)', master_port=3306(主庫端口), master_log_file='mysql-bin.000002(上一步查看到的主庫日志文件名稱)',master_log_pos=2079(上一步查看到的主庫日志文件位置);
mysql> change master to master_host='121.41.53.91', master_user='root', master_password='123456', master_port=3306, master_log_file='mysql-bin.000003',master_log_pos=612;
Query OK, 0 rows affected, 1 warning (0.02 sec)

從庫啟動主從復制，查看是否連接主庫成功

# 啟動從庫復制主庫
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)# 查看主從復制狀態，查看Slave_IO_Running、Slave_SQL_Running 是否為yes
mysql> show slave status\G;
*************************** 1. row ***************************Slave_IO_State: Waiting for master to send eventMaster_Host: 121.41.53.91  # 綁定的主庫ipMaster_User: root	# 主庫用戶Master_Port: 3306	# 主庫端口Connect_Retry: 60	Master_Log_File: mysql-bin.000003 # 主庫同步日志，從這讀取主庫數據Read_Master_Log_Pos: 612Relay_Log_File: edu-mysql-relay-bin.000002 # 從庫中繼日志Relay_Log_Pos: 320Relay_Master_Log_File: mysql-bin.000003Slave_IO_Running: Yes   # 這里是yes 說明復制成功Slave_SQL_Running: Yes	 # 這里是yes 說明復制成功Replicate_Do_DB: Replicate_Ignore_DB: Replicate_Do_Table: Replicate_Ignore_Table: Replicate_Wild_Do_Table: Replicate_Wild_Ignore_Table: Last_Errno: 0Last_Error: Skip_Counter: 0Exec_Master_Log_Pos: 612Relay_Log_Space: 531Until_Condition: NoneUntil_Log_File: Until_Log_Pos: 0Master_SSL_Allowed: NoMaster_SSL_CA_File: Master_SSL_CA_Path: Master_SSL_Cert: Master_SSL_Cipher: Master_SSL_Key: Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: NoLast_IO_Errno: 0Last_IO_Error: Last_SQL_Errno: 0Last_SQL_Error: Replicate_Ignore_Server_Ids: Master_Server_Id: 100Master_UUID: cfb53930-7fa2-11ee-8ea9-00163e2859d2Master_Info_File: /usr/local/mysql/3307/data/master.infoSQL_Delay: 0SQL_Remaining_Delay: NULLSlave_SQL_Running_State: Slave has read all relay log; waiting for more updatesMaster_Retry_Count: 86400Master_Bind: Last_IO_Error_Timestamp: Last_SQL_Error_Timestamp: Master_SSL_Crl: Master_SSL_Crlpath: Retrieved_Gtid_Set: Executed_Gtid_Set: Auto_Position: 0Replicate_Rewrite_DB: Channel_Name: Master_TLS_Version: 
1 row in set (0.00 sec)# 停止從庫復制主庫
mysql> stop slave;
Query OK, 0 rows affected (0.01 sec)

測試主從復制是否成功，在主庫建表，插入數據，查看從庫是否也有

在主庫執行操作：

新增庫
新增表
新增數據
修改數據
刪除數據

查看從庫3307是否發生變化

# 進入主庫3306
root@songdanminserver:[/usr/local/mysql/3306]mysql -uroot -h127.0.0.1 -p -P3306
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 16
Server version: 5.7.36-log MySQL Community Server (GPL)Copyright (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.
# 新建數據庫 my_test
mysql> create database my_test;
Query OK, 1 row affected (0.00 sec)mysql> use my_test;
Database changed
mysql> CREATE TABLE test (->   id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,->   name VARCHAR(30) NOT NULL,->   email VARCHAR(50) NOT NULL,->   reg_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP-> );
Query OK, 0 rows affected (0.01 sec)
# 插入初識數據
mysql> INSERT INTO test (name, email)-> VALUES ('John Doe', 'john@example.com');
Query OK, 1 row affected (0.00 sec)# 查看從庫變化