MySQL主从数据复制问题解决办法

mysql主从复制，经常会遇到错误而导致slave端复制中断，这个时候一般就需要人工干预，跳过错误才能继续
跳过错误有两种方式：
1.跳过指定数量的事务：
mysql>slave stop;
mysql>set global sql_slave_skip_counter=1;        #跳过一个事务
mysql>slave start

2.修改mysql的配置文件，通过slave_skip_errors参数来跳所有错误或指定类型的错误
vi /etc/my.cnf
[mysqld]
slave-skip-errors=1062,1053,1146 #跳过指定error no类型的错误
#slave-skip-errors=all #跳过所有错误

注意：当配置文件里写两行：
slave-skip-errors=1062
slave-skip-errors=1032时，第二个参数会覆盖第一个参数。所以一定要写到同一行，并用逗号分隔。

虽然slave会跳过这些错误，继续复制，但是仍会以Warning的形式记录到错误日志中，如：

160620 10:40:17 [Warning] Slave SQL: Could not execute Write_rows event on table dba.t; Duplicate entry '10' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log mysql-bin.000033, end_log_pos 1224, Error_code: 1062

重启Mysql服务

那些没有被复制的错误数据会输出到日志中

如：

 Error_code: 1062
Aug 16 17:44:53 mysql75 mysqld: 2017-08-16T09:44:53.142158Z 2 [Note] Slave SQL for channel '': Could not execute Query event. Detailed error: Duplicate entry '2017-08-14-3002-15616-62' for key 'PRIMARY';, Error_code: 1062
Aug 16 17:44:57 mysql75 mysqld: 2017-08-16T09:44:57.910737Z 2 [Note] Slave SQL for channel '': Could not execute Query event. Detailed error: Duplicate entry '2017-08-14-3002-15626-84' for key 'PRIMARY';, Error_code: 1062
Aug 16 17:44:57 mysql75 mysqld: 2017-08-16T09:44:57.911141Z 2 [Note] Slave SQL for channel '': Could not execute Query event. Detailed error: Duplicate entry '2017-08-14-3002-15626-85' for key 'PRIMARY';, Error_code: 1062
Aug 16 17:44:57 mysql75 mysqld: 2017-08-16T09:44:57.911918Z 2 [Note] Slave SQL for channel '': Could not execute Query event. Detailed error: Duplicate entry '2017-08-14-3002-15626-87' for key 'PRIMARY';, Error_code: 1062
Aug 16 17:44:57 mysql75 mysqld: 2017-08-16T09:44:57.912676Z 2 [Note] Slave SQL for channel '': Could not execute Query event. Detailed error: Duplicate entry '2017-08-14-3002-15626-88' for key 'PRIMARY';, Error_code: 1062
Aug 16 17:44:57 mysql75 mysqld: 2017-08-16T09:44:57.913248Z 2 [Note] Slave SQL for channel '': Could not execute Query event. Detailed error: Duplicate entry '2017-08-14-3002-15626-89' for key 'PRIMARY';, Error_code: 1062
Aug 16 17:44:57 mysql75 mysqld: 2017-08-16T09:44:57.913808Z 2 [Note] Slave SQL for channel '': Could not execute Query event. Detailed error: Duplicate entry '2017-08-14-3002-15626-90' for key 'PRIMARY';, Error_code: 1062
Aug 16 17:44:57 mysql75 mysqld: 2017-08-16T09:44:57.914573Z 2 [Note] Slave SQL for channel '': Could not execute Query event. Detailed error: Duplicate entry '2017-08-14-3002-15626-91' for key 'PRIMARY';, Error_code: 1062
Aug 16 17:46:18 mysql75 mysqld: 2017-08-16T09:46:18.933328Z 0 [Note] InnoDB: page_cleaner: 1000ms intended loop took 15293ms. The settings might not be optimal. (flushed=4427 and evicted=0, during the time.)
Aug 16 17:48:48 mysql75 mysqld: 2017-08-16T09:48:48.759770Z 0 [Note] InnoDB: page_cleaner: 1000ms intended loop took 4020ms. The settings might not be optimal. (flushed=4850 and evicted=0, during the time.)
Aug 16 17:49:30 mysql75 mysqld: 2017-08-16T09:49:30.383725Z 0 [Note] InnoDB: page_cleaner: 1000ms intended loop took 4139ms. The settings might not be optimal. (flushed=4984 and evicted=0, during the time.)

发生这种情况，一般是主机断电引起的！！