MySQL的GTID複製與傳統複製的相互切換

MySQL的GTID複製與傳統複製的相互轉換

• 1. GTID複製轉換成傳統複製
• 1.1 環境準備
• 1.2 中止slave
• 1.3 查看當前主從狀態
• 1.4 change master
• 1.5 啓動主從複製
• 1.6 在線關閉主從服務器的GTID
• 2. 傳統複製轉換成GTID複製
• 2.1 環境準備
• 2.2 將enforce_gtid_consistency設置爲warn
• 2.3 將enforce_gtid_consistency設置爲on
• 2.4 設置GTID模式爲off_permissive
• 2.5 設置GTID模式爲on_permissive
• 2.6 檢查從庫Ongoing_anonymous_transaction_count狀態值
• 2.7 確保全部的匿名事務已經被徹底複製到全部的slave上
• 2.8 設置GTID_MODE爲on
• 2.9 change master

1. GTID複製轉換成傳統複製

上篇博文已經介紹了MySQL 5.7版本的GTID複製模式的搭建，下面操做將GTID複製轉換成傳統複製模式。

1.1 環境準備

類型	ip	prot	server-id
master	192.168.56.100	3307	1003307
slave	192.168.56.200	3307	2003307

1.2 中止slave

root@localhost [(none)] 09:38:41>stop slave

1.3 查看當前主從狀態

記錄Relay_Master_Log_File和Exec_Master_Log_Pos信息。

root@localhost [(none)] 09:41:22>show slave status\G
*************************** 1. row ***************************
               Slave_IO_State: 
                  Master_Host: 192.168.56.100
                  Master_User: repl
                  Master_Port: 3307
                Connect_Retry: 60
              Master_Log_File: my3307_binlog.000005
          Read_Master_Log_Pos: 194
               Relay_Log_File: mysqldb2-relay-bin.000010
                Relay_Log_Pos: 375
        Relay_Master_Log_File: my3307_binlog.000005
             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: 194
              Relay_Log_Space: 585
              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: 1003307
                  Master_UUID: 3a068bf8-cdeb-11e8-8176-080027b0b461
             Master_Info_File: mysql.slave_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: 3a068bf8-cdeb-11e8-8176-080027b0b461:1-12
                Auto_Position: 1
         Replicate_Rewrite_DB: 
                 Channel_Name: 
           Master_TLS_Version: 
1 row in set (0.00 sec)

1.4 change master

根據上面記錄的Relay_Master_Log_File和Exec_Master_Log_Pos信息，change master：

root@localhost [(none)] 09:41:26>change master to master_log_file='my3307_binlog.000005',master_log_pos=194,master_auto_position=0;
Query OK, 0 rows affected (0.01 sec)

#參數解釋：
master_auto_position=0 表示禁用master_auto_position

1.5 啓動主從複製

root@localhost [test] 09:51:28>start slave;

1.6 在線關閉主從服務器的GTID

root@localhost [test] 09:55:01> set global gtid_mode=on_permissive;
Query OK, 0 rows affected (0.01 sec)

root@localhost [test] 09:55:25> set global gtid_mode=off_permissive;
Query OK, 0 rows affected (0.01 sec)

root@localhost [test] 09:55:58> set global gtid_mode=off;
Query OK, 0 rows affected (0.01 sec)

root@localhost [test] 09:56:09> set global enforce_gtid_consistency = 0;
Query OK, 0 rows affected (0.00 sec)

root@localhost [test] 09:57:34> show variables like '%gtid%';
+----------------------------------+-----------+
| Variable_name                    | Value     |
+----------------------------------+-----------+
| binlog_gtid_simple_recovery      | ON        |
| enforce_gtid_consistency         | OFF       |
| gtid_executed_compression_period | 1000      |
| gtid_mode                        | OFF       |
| gtid_next                        | AUTOMATIC |
| gtid_owned                       |           |
| gtid_purged                      |           |
| session_track_gtids              | OFF       |
+----------------------------------+-----------+
8 rows in set (0.01 sec)

能夠把 gtid_mode=off 與 enforce_gtid_consistency=OFF 寫入配置文件my.cnf中，重啓以後也能生效。

2. 傳統複製轉換成GTID複製

此博文介紹了MySQL 5.7版本的傳統複製模式的搭建，下面操做將傳統複製轉換成GTID複製模式。

2.1 環境準備

類型	ip	prot	server-id
master	192.168.56.100	3306	1003306
slave	192.168.56.200	3306	2003306

2.2 將enforce_gtid_consistency設置爲warn

在MySQL每一個實例上， 將enforce_gtid_consistency設置爲warn

root@localhost [(none)] 10:21:01> set @@global.enforce_gtid_consistency=warn;

【注意】：執行完這條語句後，若是出現GTID不兼容的語句用法，會在error log記錄相關信息，那麼須要調整該程序避免不兼容的寫法，直到徹底沒有不兼容的語句。

2.3 將enforce_gtid_consistency設置爲on

在 2.2完成後，若是沒有不兼容語句，能夠把MySQL每一個實例的ENFORCE_GTID_CONSISTENCY值設置爲on。

root@localhost [(none)] 11:05:11> set @@global.enforce_gtid_consistency=on;
Query OK, 0 rows affected (0.00 sec)

2.4 設置GTID模式爲off_permissive

將全部MySQL實例的GTID模式設置爲off_permissive

root@localhost [(none)] 11:06:55>SET @@GLOBAL.GTID_MODE = OFF_PERMISSIVE;
Query OK, 0 rows affected (0.01 sec)

2.5 設置GTID模式爲on_permissive

root@localhost [(none)] 11:12:20> SET @@GLOBAL.GTID_MODE = ON_PERMISSIVE;
Query OK, 0 rows affected (0.01 sec)

2.6 檢查從庫Ongoing_anonymous_transaction_count狀態值

檢查從庫Ongoing_anonymous_transaction_count狀態值是否爲0，若是爲0，一味着沒有等待的事務，能夠進行下一步操做

root@localhost [(none)] 11:13:09>SHOW STATUS LIKE 'ONGOING_ANONYMOUS_TRANSACTION_COUNT';
+-------------------------------------+-------+
| Variable_name                       | Value |
+-------------------------------------+-------+
| Ongoing_anonymous_transaction_count | 0     |
+-------------------------------------+-------+
1 row in set (0.00 sec)

2.7 確保全部的匿名事務已經被徹底複製到全部的slave上

root@localhost [(none)] 11:29:55>show slave status\G
*************************** 1. row ***************************
...
        Relay_Master_Log_File: my3306_binlog.000090
...
          Exec_Master_Log_Pos: 194
...

#在slave上使用函數：
root@localhost [(none)] 11:30:01>SELECT MASTER_POS_WAIT('my3306_binlog.000090', 194);
+----------------------------------------------+
| MASTER_POS_WAIT('my3306_binlog.000090', 194) |
+----------------------------------------------+
|                                            0 |
+----------------------------------------------+
1 row in set (0.00 sec)
返回結果大於或等於0就說明匿名事務已經所有複製完成

2.8 設置GTID_MODE爲on

root@localhost [(none)] 11:31:36>SET @@GLOBAL.GTID_MODE = ON;
Query OK, 0 rows affected (0.01 sec)

2.9 change master

root@localhost [(none)] 11:37:17>STOP slave;
Query OK, 0 rows affected (0.00 sec)

root@localhost [(none)] 11:37:24>change master to master_auto_position=1;
Query OK, 0 rows affected (0.00 sec)

root@localhost [(none)] 11:37:52>start slave;
Query OK, 0 rows affected (0.00 sec)