GTID 复制、主从不一致跳过操作、快速切换master

1. 部署

GTID 全局事务标识  mysql 5.6 加入

1.1 准备

配置文件

## gtid repl config need
server_id=52
#开启gtid
gtid_mode=on
#开启基于gtid复制
enforce_gtid_consistency=on
log-bin=mysql52-bin
# slave端日志
log-slave-updates=1
binlog_format=row
# slave启动时不会自动开启复制
skip-slave-start=1

# choice
expire_logs_days =20

重启数据库

（5.7.6以上可以动态而不重启）

权限

GRANT REPLICATION SLAVE,REPLICATION CLIENT ON *.* TO 'replrepl'@'10.27.%' iDENTIFIED BY 'gtidpwd' ;

1.2 启动复制

1.2.1 新库所有binglog全 方式

从库上

change master to master_host='10.27.247.52',master_port=3306,master_user='replrepl',master_password='gtidpwd',master_auto_position=1;

start slave

1.2.2 老库binglog不齐全 方式

#TODO 

获取GTID

从库设置跳过 set @@global.gtid_purged='uuid:interval[-interval]'

主库状态检查

mysql> show master statusG
*************************** 1. row ***************************
             File: mysql52-bin.000001
         Position: 467
     Binlog_Do_DB: 
 Binlog_Ignore_DB: 
Executed_Gtid_Set: b149ed20-eb22-11e8-9d63-005056bb87dc:1
1 row in set (0.00 sec)

从库状态检查

mysql> show slave statusG
*************************** 1. row ***************************
               Slave_IO_State: 
                  Master_Host: 10.27.247.52
                  Master_User: replrepl
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: 
          Read_Master_Log_Pos: 4
               Relay_Log_File: tqhtest-53-relay-bin.000001
                Relay_Log_Pos: 4
        Relay_Master_Log_File: 
             Slave_IO_Running: No
            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: 0
                   Last_Error: 
                 Skip_Counter: 0
          Exec_Master_Log_Pos: 0
              Relay_Log_Space: 154
              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: 0
               Last_SQL_Error: 
  Replicate_Ignore_Server_Ids: 
             Master_Server_Id: 0
                  Master_UUID: 
             Master_Info_File: /var/lib/mysql/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: 
               Master_SSL_Crl: 
           Master_SSL_Crlpath: 
           Retrieved_Gtid_Set: 
            Executed_Gtid_Set: 0189c282-eb22-11e8-ab4b-005056bbe192:1
                Auto_Position: 1
         Replicate_Rewrite_DB: 
                 Channel_Name: 
           Master_TLS_Version: 
1 row in set (0.00 sec)

mysql> start slave;

与非GTID复制比较

主库多了 Executed_Gtid_Set: b149ed20-eb22-11e8-9d63-005056bb87dc:1

基于gtid的replication	基本replication
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates ... Retrieved_Gtid_Set: b149ed20-eb22-11e8-9d63-005056bb87dc:1 Executed_Gtid_Set: 0189c282-eb22-11e8-ab4b-005056bbe192:1, b149ed20-eb22-11e8-9d63-005056bb87dc:1 Auto_Position: 1 Replicate_Rewrite_DB: Channel_Name: Master_TLS_Version:	Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it ... Retrieved_Gtid_Set: Executed_Gtid_Set: Auto_Position: 0

主库uuid

从库uuid

2 skip

2.1 信息

从库信息， 由于无法顺利replication， exec状态落后于retiried状态

主库信息

2.2 传统

使用传统方式报错

mysql> set global sql_slave_skip_counter=1;
ERROR 1858 (HY000): sql_slave_skip_counter can not be set when the server is running with @@GLOBAL.GTID_MODE = ON. Instead, for each transaction that you want to skip, generate an empty transaction with the same GTID as the transaction
mysql>

2.3 gitd方式skip

确认数据不同步原因后，进行skip操作

接受到的主库事务号为13，已exec的事务号是11，故跳过12先

mysql> stop slave;
Query OK, 0 rows affected (0.00 sec)

mysql> set GTID_NEXT='b149ed20-eb22-11e8-9d63-005056bb87dc:12';
Query OK, 0 rows affected (0.00 sec)

mysql> begin;commit;
Query OK, 0 rows affected (0.00 sec)

Query OK, 0 rows affected (0.00 sec)

mysql> set GTID_NEXT='AUTOMATIC';
Query OK, 0 rows affected (0.00 sec)

mysql> start slave;
Query OK, 0 rows affected (0.00 sec)

mysql> 

检查slave status已经正常。

后续，确认原因，检查一致性。

2 利用GTID replication

2.1 快速切换master

stop slave
change master to master_host='10.27.247.52',master_port=3306,master_user='replrepl',master_password='gtidpwd',master_auto_position=1;

start slave

由于不需要指定logfilename与pos， 可以快速切换，快速变更复制拓扑。基于此特性，可以做灵活的架构。

3 原始replication切换为基于gtid的replication

5.7.6之前版本需要停服务

之后版本可以动态调整。