1.1.1.HA: GTID_MODE配置不一致 【环境描述】 msyql5.6.14 【报错信息】 初始状态Master和Slave都开启了enforce-gtid-consistency和gtid-mode,然后在Master上把它俩都修改成了off关闭状态,这时,Slave发生报错: Last_IO_Error: The slave IO thread stops
1.1.1. HA: GTID_MODE配置不一致
【环境描述】
msyql5.6.14
【报错信息】
初始状态Master和Slave都开启了enforce-gtid-consistency和gtid-mode,然后在Master上把它俩都修改成了off关闭状态,这时,Slave发生报错:
Last_IO_Error: The slave IO thread stopsbecause the master has @@GLOBAL.GTID_MODE OFF and this server has@@GLOBAL.GTID_MODE ON
【报错原因】
MySQL的Master和Slave必须同时开启或者关闭enforce-gtid-consistency和gtid-mode功能,即要保持一致。
【解决方法】
关闭Slave上的enforce-gtid-consistency和gtid-mode功能。
【参考资料】
gtid-mode用来设置是否开启GTID功能,如果要开启GTID功能,需要同时开启log-bin和log_slave_updates功能,另外还需要开启enforce_gtid_consistency功能。gtid_mode参数可以设置为on、off、upgrade_step_1、upgrade_step_2四种值,其中upgrade_step_1和upgrade_step_2是给将来mysql可能的新功能预留的,对当前的myql没有任何意义。同时,mysql建议在mysql_upgrade的时候,关闭gtid_mode功能和enforce_gtid_consistency功能,因为Mysql在upgrade期间可能会操作非事务的MyISAM存储引擎表,会引起报错。

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