Mysql主从同步报错解决：Fatal error: The slave I/O thread stops because master and slave have equal..

报错信息：

  在搭建Mysql主从架构过程中，由于从服务器是克隆的主服务器系统，导致主从Mysql uuid相同， Slave_IO无法启动，报错如下：
  Last_IO_Error: Fatal error: The slave I/O thread stops because master and slave have equal MySQL server UUIDs; these UUIDs must be different for replication to work.

解决方法：

  找到auto.cnf文件，修改里面的uuid值，保证各个db的uuid不一样，重启db即可。

1.查看主库与从库UUID

[root@localhost ~]# find / -name auto.cnf
/var/lib/mysql/auto.cnf

[root@localhost ~]# cat /var/lib/mysql/auto.cnf    //查看主数据库auto.cnf文件中的UUID信息
[auto]
server-uuid=e46c9961-5780-11ea-bf2f-000c291a8b6b

[root@localhost ~]# mysql -uroot -p123qqq...A
...
mysql> show variables like '%server_uuid%';   //查看主数据库UUID
+---------------+--------------------------------------+
| Variable_name | Value                                |
+---------------+--------------------------------------+
| server_uuid   | e46c9961-5780-11ea-bf2f-000c291a8b6b |
+---------------+--------------------------------------+

[root@test2 ~]# find / -name auto.cnf
/var/lib/mysql/auto.cnf

[root@test2 ~]# cat /var/lib/mysql/auto.cnf    //查看从数据库auto.cnf中的UUID信息
[auto]
server-uuid=e46c9961-5780-11ea-bf2f-000c291a8b6b

[root@test2 ~]# mysql -uroot -p123qqq...A
...
mysql> show variables like '%server_uuid%';   //查看从数据库UUID
+---------------+--------------------------------------+
| Variable_name | Value                                |
+---------------+--------------------------------------+
| server_uuid   | e46c9961-5780-11ea-bf2f-000c291a8b6b |
+---------------+--------------------------------------+

2.修改主库或者从库auto.cnf文件的UUID

[root@localhost ~]# vim /var/lib/mysql/auto.cnf   //修改主库的auto.cnf文件的UUID
[auto]
server-uuid=e46c9961-5780-11ea-bf2f-000c128a8b6b   

[root@localhost ~]# systemctl restart mysqld

3.从库重启slave进程，查看slave状态

[root@test2 ~]# mysql -uroot -p123qqq...A
...
mysql> stop slave;

mysql> start slave;

mysql> show slave status\G;
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 192.168.2.128
                  Master_User: mysqluser
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: db128.000002
          Read_Master_Log_Pos: 452757169
               Relay_Log_File: test2-relay-bin.000002
                Relay_Log_Pos: 3205508
        Relay_Master_Log_File: db128.000002
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB:
          Replicate_Ignore_DB:
           Replicate_Do_Table:
       Replicate_Ignore_Table:
      Replicate_Wild_Do_Table:
  Replicate_Wild_Ignore_Table:
                   Last_Errno: 0
                   Last_Error:
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 452757169
              Relay_Log_Space: 3205715
              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: 0
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno: 0
                Last_IO_Error:
               Last_SQL_Errno: 0
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id: 128
                  Master_UUID: e46c9961-5780-11ea-bf2f-000c128a8b6b
             Master_Info_File: /var/lib/mysql/master.info
                    SQL_Delay: 0
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
           Master_Retry_Count: 86400
                  Master_Bind:
      Last_IO_Error_Timestamp:
     Last_SQL_Error_Timestamp:
               Master_SSL_Crl:
           Master_SSL_Crlpath:
           Retrieved_Gtid_Set:
            Executed_Gtid_Set:
                Auto_Position: 0
         Replicate_Rewrite_DB:
                 Channel_Name:
           Master_TLS_Version:
1 row in set (0.00 sec)

 可以看到IO线程、SQL线程都是Yes状态。