MySQL5.7在线开启/关闭GTID
MySQL5.7在线开启/关闭GTID
环境介绍
Part1:写在最前
截止本文撰写当日，MySQL5.7.16是官网的最新稳定版，本文将用MySQL5.7.16来进行演示。从MySQL5.6开始，支持了GTID复制模式，这种模式其实是把双刃剑，虽然容易搭建主从复制了，但使用不当，就容易出现一些错误，例如error 1236。在MySQL5.6如果开启GTID模式，需要在my.cnf中加入以下几个参数：
①log-bin=mysql-bin
②binlog_format=row
③log_slave_updates=1
④gtid_mode=ON
⑤enforce_gtid_consistency=ON
Warning:警告这里的一些参数不是动态参数，也就是需要重启mysql才能生效。
Part2:环境
[root@HE1 ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.7.16-log MySQL Community Server (GPL)
Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> select version();
+------------+
| version() |
+------------+
| 5.7.16-log |
+------------+
1 row in set (0.00 sec)
mysql> show global variables like 'log_slave%';
+-------------------+-------+
| Variable_name | Value |
+-------------------+-------+
| log_slave_updates | OFF |
+-------------------+-------+
1 row in set (0.00 sec)MySQL5.6开启GTID需要开启log_slave_updates参数，否则启动报错，而5.7不在需要开启该参数。
实战
Part1:搭建传统复制模式
本文环境HE1为从，HE3为主库
[root@HE1 ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 5.7.16-log MySQL Community Server (GPL)
Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.1.250
Master_User: mysync
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000002
Read_Master_Log_Pos: 1694
Relay_Log_File: HE1-relay-bin.000002
Relay_Log_Pos: 320
Relay_Master_Log_File: mysql-bin.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: 1694
Relay_Log_Space: 525
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: 1250
Master_UUID: 82b160c7-9a8f-11e6-8412-000c29c6361d
Master_Info_File: /data/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)Part2:传统复制模式切换为GTID
①主库从库都需执行以下命令
mysql> set global gtid_mode='OFF_PERMISSIVE';
Query OK, 0 rows affected (0.01 sec)
mysql> set global gtid_mode='ON_PERMISSIVE';
Query OK, 0 rows affected (0.01 sec)
mysql> set global enforce_gtid_consistency=ON;
Query OK, 0 rows affected (0.00 sec)
mysql> set global gtid_mode='ON';
Query OK, 0 rows affected (0.00 sec)②主库插数从库执行
mysql> show master status;
+------------------+----------+--------------+------------------+----------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+----------------------------------------+
| mysql-bin.000005 | 154 | | | 82b160c7-9a8f-11e6-8412-000c29c6361d:1 |
+------------------+----------+--------------+------------------+----------------------------------------+
1 row in set (0.00 sec)可以看到gtid_set下面有数了，这说明已经开启了gtid模式
Part3:GTID变更为传统模式
mysql> stop slave;-----从库执行 Query OK, 0 rows affected (0.00 sec) mysql> set global gtid_mode='ON_PERMISSIVE'; Query OK, 0 rows affected (0.00 sec) mysql> set global gtid_mode='OFF_PERMISSIVE'; Query OK, 0 rows affected (0.01 sec) mysql> CHANGE MASTER TO MASTER_AUTO_POSITION=0; Query OK, 0 rows affected (0.05 sec) mysql> set global gtid_mode='OFF'; Query OK, 0 rows affected (0.00 sec) mysql> start slave; Query OK, 0 rows affected (0.00 sec) mysql> show variables like '%gtid%'; +----------------------------------+----------------------------------------+ | Variable_name | Value | +----------------------------------+----------------------------------------+ | binlog_gtid_simple_recovery | ON | | enforce_gtid_consistency | ON | | gtid_executed_compression_period | 1000 | | gtid_mode | OFF | | gtid_next | AUTOMATIC | | gtid_owned | | | gtid_purged | 82b160c7-9a8f-11e6-8412-000c29c6361d:1 | | session_track_gtids | OFF | +----------------------------------+----------------------------------------+ 8 rows in set (0.01 sec)
可以看到这里GTID模式已经关了，下面再次开启GTID模式来观察id的变化
mysql> set global gtid_mode='OFF_PERMISSIVE';
Query OK, 0 rows affected (0.01 sec)
mysql> set global gtid_mode='ON_PERMISSIVE';
Query OK, 0 rows affected (0.01 sec)
mysql> set global enforce_gtid_consistency=ON;
Query OK, 0 rows affected (0.00 sec)
mysql> set global gtid_mode='ON';
Query OK, 0 rows affected (0.01 sec)
mysql>
mysql>
mysql> show variables like '%gtid%';
+----------------------------------+----------------------------------------+
| Variable_name | Value |
+----------------------------------+----------------------------------------+
| binlog_gtid_simple_recovery | ON |
| enforce_gtid_consistency | ON |
| gtid_executed_compression_period | 1000 |
| gtid_mode | ON |
| gtid_next | AUTOMATIC |
| gtid_owned | |
| gtid_purged | 82b160c7-9a8f-11e6-8412-000c29c6361d:1 |
| session_track_gtids | OFF |
+----------------------------------+----------------------------------------+
8 rows in set (0.00 sec)
主库做操作，从库执行如下命令会看到gtid_set的值在变化
mysql> show master status;
+------------------+----------+--------------+------------------+------------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+------------------------------------------+
| mysql-bin.000011 | 154 | | | 82b160c7-9a8f-11e6-8412-000c29c6361d:1-2 |
+------------------+----------+--------------+------------------+------------------------------------------+
1 row in set (0.00 sec)
mysql> show master status;
+------------------+----------+--------------+------------------+------------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+------------------------------------------+
| mysql-bin.000011 | 154 | | | 82b160c7-9a8f-11e6-8412-000c29c6361d:1-3 |
+------------------+----------+--------------+------------------+------------------------------------------+
1 row in set (0.00 sec)——总结——
MySQL5.7开启/关闭GTID，不用重启mysql，这大大提高了GTID的易用性。由于笔者的水平有限，编写时间也很仓促，文中难免会出现一些错误或者不准确的地方，不妥之处恳请读者批评指正。