主从复制
复制基本原理
MySQL复制过程分为三步：
- Master将改变记录到二进制日志(Binary Log)。这些记录过程叫做二进制日志事件，
Binary Log Events； - Slave将Master的
Binary Log Events拷贝到它的中继日志(Replay Log); - Slave重做中继日志中的事件，将改变应用到自己的数据库中。MySQL复制是异步且串行化的。
复制基本原则
- 每个Slave只有一个Master。
- 每个Slave只能有一个唯一的服务器ID。
- 每个Master可以有多个Salve。
一主一从配置
1、基本要求：Master和Slave的MySQL服务器版本一致且后台以服务运行。
# 创建mysql-slave1实例 docker run -p 3307:3306 --name mysql-slave1 \ -v /root/mysql-slave1/log:/var/log/mysql \ -v /root/mysql-slave1/data:/var/lib/mysql \ -v /root/mysql-slave1/conf:/etc/mysql \ -e MYSQL_ROOT_PASSWORD=333 \ -d mysql:5.7
2、主从配置都是配在[mysqld]节点（my.ini或my.cnf）下，都是小写
# Master配置 [mysqld] server-id=1 # 必须 log-bin=/var/lib/mysql/mysql-bin # 必须 read-only=0 # 设置主机可读可写
binlog-ignore-db=mysql # 在复制时忽略数据库
# Slave配置 [mysqld] server-id=2 # 必须 log-bin=/var/lib/mysql/mysql-bin
3、Master配置
# 1、GRANT REPLICATION SLAVE ON *.* TO 'username'@'从机IP地址' IDENTIFIED BY 'password'; mysql> GRANT REPLICATION SLAVE ON *.* TO 'zhangsan'@'172.18.0.3' IDENTIFIED BY '123456'; Query OK, 0 rows affected, 1 warning (0.01 sec) # 2、刷新命令 mysql> FLUSH PRIVILEGES; Query OK, 0 rows affected (0.00 sec) # 3、记录下File和Position # 每次配从机的时候都要SHOW MASTER STATUS;查看最新的File和Position mysql> SHOW MASTER STATUS; +------------------+----------+--------------+------------------+-------------------+ | File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set | +------------------+----------+--------------+------------------+-------------------+ | mysql-bin.000001 | 602 | | mysql | | +------------------+----------+--------------+------------------+-------------------+ 1 row in set (0.00 sec)
4、Slave从机配置
CHANGE MASTER TO MASTER_HOST='172.18.0.4', MASTER_USER='zhangsan', MASTER_PASSWORD='123456', MASTER_LOG_FILE='mysql-bin.File的编号', MASTER_LOG_POS=Position的最新值;
# 1、使用用户名密码登录进Master
mysql> CHANGE MASTER TO MASTER_HOST='172.18.0.4',
-> MASTER_USER='zhangsan',
-> MASTER_PASSWORD='123456',
-> MASTER_LOG_FILE='mysql-bin.000001',
-> MASTER_LOG_POS=602;
Query OK, 0 rows affected, 2 warnings (0.02 sec)
# 2、开启从服务器复制功能（在从服务器上开）
mysql> START SLAVE;
Query OK, 0 rows affected (0.00 sec)
# 3、查看Slave状态
# Slave_IO_Running 和 Slave_SQL_Running 必须同时为Yes 说明主从复制配置成功！
mysql> SHOW SLAVE STATUS\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event # Slave待命状态
Master_Host: 172.18.0.4
Master_User: zhangsan
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 602
Relay_Log_File: b030ad25d5fe-relay-bin.000002
Relay_Log_Pos: 320
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 602
Relay_Log_Space: 534
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_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: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1
Master_UUID: bd047557-b20c-11ea-9961-0242ac120002
Master_Info_File: /var/lib/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)
5、测试主从复制
# Master创建数据库 mysql> create database test_replication; Query OK, 1 row affected (0.01 sec) # Slave查询数据库 mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | sys | | test_replication | +--------------------+ 5 rows in set (0.00 sec)
6、停止主从复制功能
# 1、停止Slave
mysql> STOP SLAVE;
Query OK, 0 rows affected (0.00 sec)
# 2、重新配置主从
# MASTER_LOG_FILE 和 MASTER_LOG_POS一定要根据最新的数据来配
mysql> CHANGE MASTER TO MASTER_HOST='172.18.0.4',
-> MASTER_USER='zhangsan',
-> MASTER_PASSWORD='123456',
-> MASTER_LOG_FILE='mysql-bin.000001',
-> MASTER_LOG_POS=797;
Query OK, 0 rows affected, 2 warnings (0.01 sec)
mysql> START SLAVE;
Query OK, 0 rows affected (0.00 sec)
mysql> SHOW SLAVE STATUS\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 172.18.0.4
Master_User: zhangsan
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000001
Read_Master_Log_Pos: 797
Relay_Log_File: b030ad25d5fe-relay-bin.000002
Relay_Log_Pos: 320
Relay_Master_Log_File: mysql-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 797
Relay_Log_Space: 534
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_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: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1
Master_UUID: bd047557-b20c-11ea-9961-0242ac120002
Master_Info_File: /var/lib/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)