centos 6.5
mysql5.7
在从库作stop slave时报：
error:
ERROR 1794 (HY000): Slave is not configured or failed to initialize properly. You must at least set --server-id to enable either a master or a slave. Additional error messages can be found in the MySQL error log.
经分析，需要：
删除5张表，并重新导入脚本
use mysql
drop table slave_master_info;
drop table slave_relay_log_info;
drop table slave_worker_info;
drop table innodb_index_stats;
drop table innodb_table_stats;
source /usr/coolpad/mysql/share/mysql_system_tables.sql
(2)重新启动数据库
注：这一步是必须的，否则无法正常配置双主架构。