MySQL5.7开始支持多源复制，也就是多主一从的复制架构：
使用多源复制的考虑：
1、灾备作用：将各个库汇总在一起，就算是其他库都挂了（整个机房都无法连接了），还有最后一个救命稻草；
2、备份：直接在这个从库中做备份，不影响线上的数据库；
3、减少成本：不需要每个库都做一个实例，也减少了DBA的维护成本；
4、数据统计：后期的一些数据统计，需要将所有的库汇总在一起。
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实验环境：
Master1：10.157.26.132:3307
Master2：10.157.26.133:3307
Slave：10.157.26.134:3307
多源复制是支持GTID和Binlog+Position，我这里是GTID复制。
MySQL5.7的安装这里不再介绍，可以查看http://www.cnblogs.com/lizhi221/p/6813907.html
一、配置文件：
Master1和Master2:
#GTID gtid-mode = on binlog_gtid_simple_recovery=1 enforce_gtid_consistency=1 binlog_format = row skip_slave_start = 1 log-bin = /data/mysql/mysql_3307/logs/binlog/mysql-bin
Slave:
#binlog binlog_format = row server-id = 1343307 log-bin = /data/mysql/mysql_3307/logs/binlog/mysql-bin #GTID gtid-mode = on binlog_gtid_simple_recovery=1 enforce_gtid_consistency=1 #修改MySQL存储master-info和relay-info的方式，即从文件存储改为表存储 master_info_repository=TABLE relay_log_info_repository=TABLE replicate_ignore_db=mysql #忽略mysql库的同步 skip_slave_start = 1
二、主库创建复制账号：
Master1：grant replication slave,replication client on *.* to sampson_132@'10.157.26.%'identified by 'sampson_132'; Master2：grant replication slave,replication client on *.* to sampson_133@'10.157.26.%'identified by 'sampson_133';
三：从库启动复制：
mysql> change master to master_host='10.157.26.132',master_port=3307,master_user='sampson_132',master_password='sampson_132',master_auto_position=1 for channel 'Master_132'; mysql>change master to master_host='10.157.26.133',master_port=3307,master_user='sampson_133',master_password='sampson_133',master_auto_position=1 for channel 'Master_133'; mysql>start slave;
也可以start slave for channel 'Master_132 '启动单个channel的复制。
四：查看slave状态
【也可以直接show slave status for channel 'Master_132' G查看各个channel的复制状态】
mysql> show slave statusG *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 10.157.26.132 Master_User: sampson_132 Master_Port: 3307 Connect_Retry: 60 Master_Log_File: mysql-bin.000001 Read_Master_Log_Pos: 154 Relay_Log_File: relay_log-master_132.000002 Relay_Log_Pos: 367 Relay_Master_Log_File: mysql-bin.000001 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: mysql 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: 154 Relay_Log_Space: 579 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: 1323307 Master_UUID: 8785129a-3ace-11e7-9f13-fa163e48cafd Master_Info_File: mysql.slave_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: 1 Replicate_Rewrite_DB: Channel_Name: master_132 Master_TLS_Version: *************************** 2. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 10.157.26.133 Master_User: sampson_133 Master_Port: 3307 Connect_Retry: 60 Master_Log_File: mysql-bin.000001 Read_Master_Log_Pos: 154 Relay_Log_File: relay_log-master_133.000002 Relay_Log_Pos: 367 Relay_Master_Log_File: mysql-bin.000001 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: mysql 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: 154 Relay_Log_Space: 579 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: 1333307 Master_UUID: 3d5ae510-3acf-11e7-82a4-fa163e8e91ad Master_Info_File: mysql.slave_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: 1 Replicate_Rewrite_DB: Channel_Name: master_133 Master_TLS_Version: 2 rows in set (0.01 sec)
通过查看performance_schema相关的表查看同步状态：
mysql> select * from performance_schema.replication_connection_statusG *************************** 1. row *************************** CHANNEL_NAME: master_132 GROUP_NAME: SOURCE_UUID: 8785129a-3ace-11e7-9f13-fa163e48cafd THREAD_ID: 89 SERVICE_STATE: ON COUNT_RECEIVED_HEARTBEATS: 1 LAST_HEARTBEAT_TIMESTAMP: 2017-05-17 16:59:45 RECEIVED_TRANSACTION_SET: LAST_ERROR_NUMBER: 0 LAST_ERROR_MESSAGE: LAST_ERROR_TIMESTAMP: 0000-00-00 00:00:00 *************************** 2. row *************************** CHANNEL_NAME: master_133 GROUP_NAME: SOURCE_UUID: 3d5ae510-3acf-11e7-82a4-fa163e8e91ad THREAD_ID: 91 SERVICE_STATE: ON COUNT_RECEIVED_HEARTBEATS: 1 LAST_HEARTBEAT_TIMESTAMP: 2017-05-17 16:59:45 RECEIVED_TRANSACTION_SET: LAST_ERROR_NUMBER: 0 LAST_ERROR_MESSAGE: LAST_ERROR_TIMESTAMP: 0000-00-00 00:00:00 2 rows in set (0.01 sec)
五、数据同步检查：
Master1建库建表并插入数据：
mysql>CREATE DATABASE /*!32312 IF NOT EXISTS*/ `sampson_132` /*!40100 DEFAULT CHARACTER SET utf8mb4 */; mysql>use sampson_132 mysql> create table t_132(id int primary key auto_increment,name varchar(20) not null); mysql> insert into t_132(id,name)values(1,'132'),(2,'132'),(3,'132'); mysql> select * from t_132; +----+------+ | id | name | +----+------+ | 1 | 132 | | 2 | 132 | | 3 | 132 | +----+------+ 3 rows in set (0.00 sec)
Master2建库建表并插入数据：
mysql> CREATE DATABASE /*!32312 IF NOT EXISTS*/ `sampson_133` /*!40100 DEFAULT CHARACTER SET utf8mb4 */; mysql> use sampson_133 mysql> create table t_133(id int primary key auto_increment,name varchar(20) not null); mysql> insert into t_133(id,name)values(1,'133'),(2,'133'),(3,'133'); mysql> select * from sampson_133.t_133; +----+------+ | id | name | +----+------+ | 1 | 133 | | 2 | 133 | | 3 | 133 | +----+------+ 3 rows in set (0.00 sec)
Slave查看数据是否同步：
mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | mysql | | performance_schema | | sampson_132 | | sampson_133 | | sys | +--------------------+ 6 rows in set (0.00 sec) mysql> select * from sampson_132.t_132; +----+------+ | id | name | +----+------+ | 1 | 132 | | 2 | 132 | | 3 | 132 | +----+------+ 3 rows in set (0.00 sec) mysql> select * from sampson_133.t_133; +----+------+ | id | name | +----+------+ | 1 | 133 | | 2 | 133 | | 3 | 133 | +----+------+ 3 rows in set (0.00 sec)
再次查看从库状态：
mysql> show slave statusG *************************** 1. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 10.157.26.132 Master_User: sampson_132 Master_Port: 3307 Connect_Retry: 60 Master_Log_File: mysql-bin.000001 Read_Master_Log_Pos: 930 Relay_Log_File: relay_log-master_132.000002 Relay_Log_Pos: 1143 Relay_Master_Log_File: mysql-bin.000001 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: mysql 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: 930 Relay_Log_Space: 1355 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: 1323307 Master_UUID: 8785129a-3ace-11e7-9f13-fa163e48cafd Master_Info_File: mysql.slave_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: 8785129a-3ace-11e7-9f13-fa163e48cafd:1-3 Executed_Gtid_Set: 3d5ae510-3acf-11e7-82a4-fa163e8e91ad:1-3, 8785129a-3ace-11e7-9f13-fa163e48cafd:1-3 Auto_Position: 1 Replicate_Rewrite_DB: Channel_Name: master_132 Master_TLS_Version: *************************** 2. row *************************** Slave_IO_State: Waiting for master to send event Master_Host: 10.157.26.133 Master_User: sampson_133 Master_Port: 3307 Connect_Retry: 60 Master_Log_File: mysql-bin.000001 Read_Master_Log_Pos: 930 Relay_Log_File: relay_log-master_133.000002 Relay_Log_Pos: 1143 Relay_Master_Log_File: mysql-bin.000001 Slave_IO_Running: Yes Slave_SQL_Running: Yes Replicate_Do_DB: Replicate_Ignore_DB: mysql 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: 930 Relay_Log_Space: 1355 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: 1333307 Master_UUID: 3d5ae510-3acf-11e7-82a4-fa163e8e91ad Master_Info_File: mysql.slave_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: 3d5ae510-3acf-11e7-82a4-fa163e8e91ad:1-3 Executed_Gtid_Set: 3d5ae510-3acf-11e7-82a4-fa163e8e91ad:1-3, 8785129a-3ace-11e7-9f13-fa163e48cafd:1-3 Auto_Position: 1 Replicate_Rewrite_DB: Channel_Name: master_133 Master_TLS_Version: 2 rows in set (0.00 sec)