一、基础信息
1. Centos7.4
2.MySQL 5.7.21
3.基于gtid的复制
二、异常描述
误把从节点当成主节点插入一条数据,同一条数据在主、从节点插入都进行了一次插入操作,导致主键冲突,slave下的SQL线程异常。
建议设置从库为只读:
set global read_only=1;--针对普通MySQL数据库用户设置为只读
set global super_read_only=1;--针对super类MySQL数据库用户设置为只读,比如root用户
my.cnf 文件设置永久只读
read_only=1
super_read_only=1;
三、处理过程
1.查看报错信息-- 报错大致如下
mysql> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.1
Master_User: repuser
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql_binlog.000023
Read_Master_Log_Pos: 2266930
Relay_Log_File: devmidsrv01kf-relay-bin.000003
Relay_Log_Pos: 423
Relay_Master_Log_File: mysql_binlog.000016
Slave_IO_Running: Yes
Slave_SQL_Running: No
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 1062
Last_Error: Could not execute Write_rows event on table testdb1.students; Duplicate entry '8' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log mysql_binlog.000016, end_log_pos 340380520
Skip_Counter: 0
Exec_Master_Log_Pos: 340380190
Relay_Log_Space: 6541566399
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: NULL
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 1062
Last_SQL_Error: Could not execute Write_rows event on table testdb1.students; Duplicate entry '8' for key 'PRIMARY', Error_code: 1062; handler error HA_ERR_FOUND_DUPP_KEY; the event's master log mysql_binlog.000016, end_log_pos 340380520
Replicate_Ignore_Server_Ids:
Master_Server_Id: 757
Master_UUID: 7bd36140-a92d-11e9-ba1f-005056a4099b
Master_Info_File: /data/mysql/3306/data/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State:
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp: 191205 16:19:02
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set: 7bd36140-a92d-11e9-ba1f-005056a4099b:835084-2324874
Executed_Gtid_Set: 7bd36140-a92d-11e9-ba1f-005056a4099b:1-835083,
bcad977d-a934-11e9-a589-005056a483f4:1-29
Auto_Position: 1
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:
1 row in set (0.00 sec)
2.确认需要跳过的gtid是关键
找到这个已经执行的gtid,加1
7bd36140-a92d-11e9-ba1f-005056a4099b:1-835083
3.跳过gtid
stop slave;
SET @@SESSION.GTID_NEXT= '7bd36140-a92d-11e9-ba1f-005056a4099b:1-835084';
BEGIN; COMMIT;
SET SESSION GTID_NEXT = AUTOMATIC;
START SLAVE;
4、检查
mysql> show slave status \G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.1
Master_User: repuser
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql_binlog.000023
Read_Master_Log_Pos: 2266930
Relay_Log_File: devmidsrv01kf-relay-bin.000003
Relay_Log_Pos: 423
Relay_Master_Log_File: mysql_binlog.000016
Slave_IO_Running: Yes
Slave_SQL_Running: Yes