mysql主从复制常见故障解决

一、主从复制常见故障

1、从库已存在数据库，主库建立同名库导致从库同步失败。报错如下：

mysql> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.222.145
Master_User: rep
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysqld-bin.000005
Read_Master_Log_Pos: 475
Relay_Log_File: mysql2-relay-bin.000004
Relay_Log_Pos: 519
Relay_Master_Log_File: mysqld-bin.000005
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: 1007
Last_Error: Error 'Can't create database 'butongbu'; database exists' on query. Default database: 'butongbu'. Query: 'create database butongbu'
Skip_Counter: 0
Exec_Master_Log_Pos: 304
Relay_Log_Space: 1065
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: 1007
Last_SQL_Error: Error 'Can't create database 'butongbu'; database exists' on query. Default database: 'butongbu'. Query: 'create database butongbu'
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1
Master_UUID: cd6ab947-045e-11e9-98a6-000c29d4d5b5
Master_Info_File: /data/3307/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: 181222 14:31:28
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
Replicate_Rewrite_DB:
Channel_Name:
Master_TLS_Version:

***解决办法：

方法一：
stop slave;
set global sql_slave_skip_counter=1;
start slave
方法二：根据错误号跳过指定错误，在从服务的my.cnf配置跳过错误
slave-name-resolve   # 忽略名字解释，MySQL慢的时候加入该参数可以提升速度
slave-skip-erros = 1032,1062,1007