概述
一般生产环境都需要定期去做一次mysql数据库主备切换演练,这里简单记录一下,后面再演示一下备份恢复的一些演练工作。
1、查看主库状态
- show processlist;
- Master has sent all binlog to slave; waiting for binlog to be updated
- show master status \G
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2、查看从库状态
- show processlist;
- show slave status \G
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3、从库停止 IO_THREAD 线程
- stop slave IO_THREAD;
- show processlist;
- show slave status \G
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4、从库切换为主库
- stop slave;
- reset master;
- reset slave all;
- show master status \G
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5、激活帐户
- SELECT DISTINCT CONCAT('User: ''',user,'''@''',host,''';') AS query FROM mysql.user;
- GRANT REPLICATION SLAVE ON *.* TO 'repl'@'%' IDENTIFIED BY 'xxx;
- FLUSH PRIVILEGES;
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6、切换原有主库为从库(原有主库执行)
- reset master;
- reset slave all;
- CHANGE MASTER TO
- MASTER_HOST='1xxx',
- MASTER_USER='repl',
- MASTER_PASSWORD='xxx,
- MASTER_PORT=3306,
- MASTER_LOG_FILE='mysql-bin.000001',
- MASTER_LOG_POS=589;
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7、检查主库
- SHOW PROCESSLIST;
- show master status \G
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8、启动从库
- SHOW PROCESSLIST;
- start slave;
- show slave status \G
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9、MySQL主从测试
9.1插入数据
9.1.1创建测试表并插入数据
- mysql> create table test123(id int(4));
- Query OK, 0 rows affected (0.01 sec)
- mysql> insert into test123 values(1);
- Query OK, 1 row affected (0.00 sec)
- mysql> insert into test123 values(2);
- Query OK, 1 row affected (0.00 sec)
- mysql> insert into test123 values(3);
- Query OK, 1 row affected (0.00 sec)
- mysql> insert into test123 values(4);
- Query OK, 1 row affected (0.00 sec)
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9.1.2从库查询:
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9.2 删除数据
9.2.1主库删除表:
- mysql> drop table test123;
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9.2.2 从库查询:
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