背景：

目前MySQL依然只支持一个Slave从一个Master复制数据，虽然也可以做到一主多备(M->S)，双主复制(M<->M)等架构，但是局限性依然很大。由于项目的要求，需要各个主库的表整合到一个地方进行统计和分析，要是每次连不同的实例操作，是一件非常耗体力的操作。所以继续一种类似多主一从的实例。

安装：

sudo apt-get install software-properties-common

sudo apt-key adv --recv-keys --keyserver hkp://keyserver.ubuntu.com:80 0xcbcb082a1bb943db

sudo add-apt-repository 'debhttp://mirrors.hustunique.com/mariadb/repo/10.0/ubuntu trusty main'

sudo apt-get update

sudo apt-get install mariadb-server

环境搭建：

Master 1：200.51(MySQL)

Master 2：200.52(MySQL)

Slave：200.73(MariaDB) 修改好server-id

确认好Master的POS：

M1:

rep@192.168.200.51 : (none) 10:26:11>show master status;

+--------------------+----------+--------------+------------------+

| File |Position | Binlog_Do_DB |Binlog_Ignore_DB |

+--------------------+----------+--------------+------------------+

| mysql-bin51.000013 | 107 | | test |

+--------------------+----------+--------------+------------------+

1 row in set (0.01 sec)

M2：

rep@192.168.200.52 : r2 10:26:23>show master status;+---------------------+----------+--------------+------------------+

| File |Position | Binlog_Do_DB |Binlog_Ignore_DB |

+---------------------+----------+--------------+------------------+

| mysql-bin_52.000106 | 107 | | test |

+---------------------+----------+--------------+------------------+

1 row in set (0.00 sec)

Slave 操作：

MariaDB [(none)]> change master 'r1' to master_host='192.168.200.51',master_user='rep',master_password='rep123456',master_log_file='mysql-bin51.000013',master_log_pos=107;

Query OK, 0 rows affected (0.23 sec)

MariaDB [(none)]> change master 'r2' to master_host='192.168.200.52',master_user='rep',master_password='rep123456',master_log_file='mysql-bin_52.000106',master_log_pos=107;

Query OK, 0 rows affected (0.25 sec)

MariaDB的change方法和MySQL有点不一样，多了一个['connection_name']，这个就是多主一从的关键。为每个主设置一个通道标识，这样就可以支持多主复制了。

如何保存复制的信息？单主复制会把复制信息保存在master.info中，在多主复制中的保存也类似，只是在最后加上通道标识名称。如：

-rw-rw---- 1mysql mysql 113 11月 17 10:30 master-r1.info

-rw-rw---- 1mysql mysql 114 11月 17 10:31 master-r2.info

-rw-rw---- 1mysql mysql 248 11月 17 10:30 mysqld-relay-bin-r1.000001

-rw-rw---- 1mysql mysql 29 11月 17 10:30 mysqld-relay-bin-r1.index

-rw-rw---- 1mysql mysql 248 11月 17 10:31 mysqld-relay-bin-r2.000001

-rw-rw---- 1mysql mysql 29 11月 17 10:31 mysqld-relay-bin-r2.index

-rw-rw---- 1 mysqlmysql 54 11月 17 10:30 relay-log-r1.info

-rw-rw---- 1mysql mysql 55 11月 17 10:31 relay-log-r2.info

查看同步：

#查看所有通道
MariaDB [(none)]> show all slaves status\G;

*************************** 1.row ***************************

Connection_name: r1

Slave_SQL_State:

Slave_IO_State:

Master_Host: 192.168.200.51

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin51.000013

Read_Master_Log_Pos: 107

Relay_Log_File: mysqld-relay-bin-r1.000001

Relay_Log_Pos: 4

Relay_Master_Log_File: mysql-bin51.000013

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: 107

Relay_Log_Space: 248

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_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

Retried_transactions: 0

Max_relay_log_size: 104857600

Executed_log_entries: 0

Slave_received_heartbeats: 0

Slave_heartbeat_period: 1800.000

Gtid_Slave_Pos:

*************************** 2.row ***************************

Connection_name: r2

Slave_SQL_State:

Slave_IO_State:

Master_Host: 192.168.200.52

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin_52.000106

Read_Master_Log_Pos: 107

Relay_Log_File: mysqld-relay-bin-r2.000001

Relay_Log_Pos: 4

Relay_Master_Log_File: mysql-bin_52.000106

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: 107

Relay_Log_Space: 248

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_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

Retried_transactions: 0

Max_relay_log_size: 104857600

Executed_log_entries: 0

Slave_received_heartbeats: 0

Slave_heartbeat_period: 1800.000

Gtid_Slave_Pos:

2 rows in set (0.00 sec)

ERROR: No query specified

#查看单个通道

MariaDB [(none)]> show slave 'r1' status\G;

*************************** 1.row ***************************

Slave_IO_State:

Master_Host: 192.168.200.51

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin51.000013

Read_Master_Log_Pos: 107

Relay_Log_File: mysqld-relay-bin-r1.000001

Relay_Log_Pos: 4

Relay_Master_Log_File: mysql-bin51.000013

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: 107

Relay_Log_Space: 248

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_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

1 row in set (0.00 sec)

ERROR: No query specified

MariaDB [(none)]> show slave 'r2' status\G;

*************************** 1.row ***************************

Slave_IO_State:

Master_Host: 192.168.200.52

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin_52.000106

Read_Master_Log_Pos: 107

Relay_Log_File: mysqld-relay-bin-r2.000001

Relay_Log_Pos: 4

Relay_Master_Log_File: mysql-bin_52.000106

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: 107

Relay_Log_Space: 248

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_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

1 row in set (0.00 sec)

ERROR: No query specified

开启同步：

#开启单个通道
MariaDB [(none)]> start slave 'r1';

Query OK, 0 rows affected (0.00 sec)

MariaDB [(none)]> start slave 'r2';

Query OK, 0 rows affected (0.00 sec)

#关闭多个通道

MariaDB [(none)]> start allslaves;

Query OK, 0 rows affected, 2 warnings (0.01 sec)

MariaDB [(none)]> show warnings;

+-------+------+--------------------+

| Level | Code |Message |

+-------+------+--------------------+

| Note | 1937 | SLAVE 'r2'started |

| Note | 1937 | SLAVE 'r1'started |

+-------+------+--------------------+

2 rows in set (0.00 sec)

通过show all slaves status 命令可知是否同步成功。

关闭同步：

#关闭单个通道
MariaDB [(none)]> stop slave 'r1';

Query OK, 0 rows affected (0.14 sec)

MariaDB [(none)]> stop slave 'r2';

Query OK, 0 rows affected (0.03 sec)

#关闭所有通道

MariaDB [(none)]> stop allslaves;

Query OK, 0 rows affected, 2 warnings (0.08 sec)

MariaDB [(none)]> show warnings;

+-------+------+--------------------+

| Level | Code |Message |

+-------+------+--------------------+

| Note | 1938 | SLAVE 'r2'stopped |

| Note | 1938 | SLAVE 'r1'stopped |

+-------+------+--------------------+

2 rows in set (0.00 sec)

多源复制在原先复制的基础上多了几个变量，现在来说明下：

MariaDB [(none)]> show allslaves status\G;

*************************** 1.row ***************************

Connection_name: r1 #master的连接名，通道名，第一个参数。

Slave_SQL_State: Slave has read all relay log;waiting for the slave I/Othread to update it

Slave_IO_State: Waiting for master to sendevent

Master_Host: 192.168.200.51

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin51.000013

Read_Master_Log_Pos: 107

Relay_Log_File: mysqld-relay-bin-r1.000005

Relay_Log_Pos: 396

Relay_Master_Log_File: mysql-bin51.000013

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: 107

Relay_Log_Space: 845

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: 1

Master_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

Retried_transactions: 0 #这个连接重试事务的次数

Max_relay_log_size: 104857600 #relay log的最大值. 如果是0的话，那么在启动的时候就会被设置成max_binlog_size的大小

Executed_log_entries: 17 #slave已经指向了多少个日志条目

Slave_received_heartbeats: 0 #我们从master收到了多少个心跳包

Slave_heartbeat_period: 1800.000 #多久从master请求一个心跳包 (以秒计算)

Gtid_Slave_Pos:

测试复制

Master 1:

rep@192.168.200.51 : (none) 01:52:34>show databases;

+--------------------+

| Database|

+--------------------+

| information_schema |

| mha_test |

| mysql |

| performance_schema |

| xtra_test |

+--------------------+

5 rows in set (0.00 sec)

rep@192.168.200.51 : (none) 01:52:37>create database r1 defaultcharset utf8;

Query OK, 1 rowaffected (0.01 sec)

rep@192.168.200.51 : (none) 01:53:36>use r1;

Database changed

rep@192.168.200.51 : r1 01:53:44>create table r1(id int not null auto_increment primary key,name varchar(30))default charset utf8;

Query OK, 0 rows affected (1.35 sec)

rep@192.168.200.51 : r1 01:54:09>insert into r1(name) values('a'),('b'),('c');

Query OK, 3 rows affected (0.01 sec)

Records: 3 Duplicates: 0 Warnings: 0

rep@192.168.200.51 : r1 01:54:56>select * from r1;

+----+------+

| id | name |

+----+------+

| 1 | a |

| 2 | b |

| 3 | c |

+----+------+

3 rows in set (0.00 sec)

Master 2:

rep@192.168.200.52 : (none) 01:52:13>create database r2 defaultcharset utf8;

Query OK, 1 rowaffected (0.01 sec)

rep@192.168.200.52 : (none) 01:54:27>use r2

Database changed

rep@192.168.200.52 : r2 01:54:30>create table r2(id int not null auto_increment primary key,name varchar(30))default charset utf8;

Query OK, 0 rows affected (0.23 sec)

rep@192.168.200.52 : r2 01:54:32>insert into r2(name) values('A'),('B'),('C');

Query OK, 3 rows affected (0.28 sec)

Records: 3 Duplicates: 0 Warnings: 0

rep@192.168.200.52 : r2 01:55:18>select * from r2;

+----+------+

| id | name |

+----+------+

| 1 | A |

| 2 | B |

| 3 | C |

+----+------+

3 rows in set (0.01 sec)

Slave:

MariaDB [(none)]> show databases;

+--------------------+

| Database|

+--------------------+

| information_schema |

| mysql |

| performance_schema |

| r1 |

| r2 |

+--------------------+

5 rows in set (0.00 sec)

MariaDB [(none)]> use r1;

Reading tableinformation for completion of table and column names

You can turn offthis feature to get a quicker startup with -A

Database changed

MariaDB [r1]> select * from r1;

+----+------+

| id | name |

+----+------+

| 1 | a |

| 2 | b |

| 3 | c |

+----+------+

3 rows in set (0.00 sec)

MariaDB [r1]> use r2;

Reading tableinformation for completion of table and column names

You can turn offthis feature to get a quicker startup with -A

Database changed

MariaDB [r2]> select * from r2;

+----+------+

| id | name |

+----+------+

| 1 | A |

| 2 | B |

| 3 | C |

+----+------+

3 rows in set (0.00 sec)

同步成功，那如何错误跳过呢（default_master_connection）？

在Master 1上创建r2数据库，因为Slave上存在，所以会报错：

Master 1：

rep@192.168.200.51 : r1 01:55:52>create database r2 defaultcharset utf8;

Query OK, 1 rowaffected (0.01 sec)

rep@192.168.200.51 : r1 01:59:51>insert into r1(name) values('d'),('e'),('f');

Query OK, 3 rows affected (0.01 sec)

Records: 3 Duplicates: 0 Warnings: 0

rep@192.168.200.51 : r1 02:04:22>select * from r1;

+----+------+

| id | name |

+----+------+

| 1 | a |

| 2 | b |

| 3 | c |

| 4 | d |

| 5 | e |

| 6 | f |

+----+------+

6 rows in set (0.00 sec)

Slave ：

MariaDB [r2]> show slave 'r1'status\G;

*************************** 1.row ***************************

Slave_IO_State: Waiting for master to sendevent

Master_Host: 192.168.200.51

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin51.000013

Read_Master_Log_Pos: 767

Relay_Log_File: mysqld-relay-bin-r1.000005

Relay_Log_Pos: 956

Relay_Master_Log_File: mysql-bin51.000013

Slave_IO_Running: Yes

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: 1007

Last_Error: Error 'Can't create database 'r2'; database exists' on query. Default database: 'r2'.Query: 'create database r2 defaultcharset utf8'

Skip_Counter: 0

Exec_Master_Log_Pos: 667

Relay_Log_Space: 1505

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: 1007

Last_SQL_Error: Error 'Can'tcreate database 'r2'; database exists' on query. Default database: 'r2'. Query: 'create database r2 default charset utf8'

Replicate_Ignore_Server_Ids:

Master_Server_Id: 1

Master_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

1 row in set (0.00 sec)

MariaDB [r1]> select * from r1;

+----+------+

| id | name |

+----+------+

| 1 | a |

| 2 | b |

| 3 | c |

+----+------+

3 rows in set (0.00 sec)

r1的同步失败了，那r2可以继续同步吗？

Master 2:

rep@192.168.200.52 : r2 01:55:59>insert into r2(name) values('D'),('E'),('F');

Query OK, 3 rows affected (0.01 sec)

Records: 3 Duplicates: 0 Warnings: 0

rep@192.168.200.52 : r2 02:02:19>select * from r2;

+----+------+

| id | name |

+----+------+

| 1 | A |

| 2 | B |

| 3 | C |

| 4 | D |

| 5 | E |

| 6 | F |

+----+------+

6 rows in set (0.01 sec)

Slave：

MariaDB [r2]> select * from r2;

+----+------+

| id | name |

+----+------+

| 1 | A |

| 2 | B |

| 3 | C |

| 4 | D |

| 5 | E |

| 6 | F |

+----+------+

6 rows in set (0.00 sec)

上面可以得出：r1同步失败之后，不影响r2的同步。想要r1同步正常，则需要忽略即跳过该错误。如：

MariaDB [r1]> stop slave 'r1';

Query OK, 0 rowsaffected (0.12 sec)

MariaDB [r1]> set @@default_master_connection='r1'; #这里是重点：指定一个通道，然后用单通道的sql_slave_skip_counter。

Query OK, 0 rows affected (0.00 sec)

MariaDB [r1]> select @@default_master_connection;

+-----------------------------+

| @@default_master_connection |

+-----------------------------+

| r1 |

+-----------------------------+

1 row in set (0.00 sec)

MariaDB [r1]> SET GLOBAL sql_slave_skip_counter =1;

Query OK, 0 rows affected (0.00 sec)

MariaDB [r1]> start slave 'r1';

Query OK, 0 rows affected (0.00 sec)

MariaDB [r1]> show slave 'r1'status\G;

*************************** 1.row ***************************

Slave_IO_State: Waiting for master to sendevent

Master_Host: 192.168.200.51

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin51.000013

Read_Master_Log_Pos: 993

Relay_Log_File: mysqld-relay-bin-r1.000006

Relay_Log_Pos: 396

Relay_Master_Log_File: mysql-bin51.000013

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: 993

Relay_Log_Space: 1731

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: 1

Master_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

1 row in set (0.00 sec)

MariaDB [r1]> select * from r1;

+----+------+

| id | name |

+----+------+

| 1 | a |

| 2 | b |

| 3 | c |

| 4 | d |

| 5 | e |

| 6 | f |

+----+------+

6 rows in set (0.00 sec)

看到跳过/忽略错误之后，r1的复制就正常了。

从上面的测试上说明，在用多主一从的复制时，需要保证各个主的MasterSchema 要唯一，不能有重复。

最后再看看如何初始化：

MariaDB [r1]> show allslaves status\G;

*************************** 1.row ***************************

Connection_name: r1

Slave_SQL_State: Slave has read all relay log;waiting for the slave I/Othread to update it

Slave_IO_State: Waiting for master to sendevent

Master_Host: 192.168.200.51

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin51.000013

Read_Master_Log_Pos: 1376

Relay_Log_File: mysqld-relay-bin-r1.000006

Relay_Log_Pos: 779

Relay_Master_Log_File: mysql-bin51.000013

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: 1376

Relay_Log_Space: 2114

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: 1

Master_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

Retried_transactions: 0

Max_relay_log_size: 104857600

Executed_log_entries: 39

Slave_received_heartbeats: 4

Slave_heartbeat_period: 1800.000

Gtid_Slave_Pos:

*************************** 2.row ***************************

Connection_name: r2

Slave_SQL_State: Slave has read all relay log;waiting for the slave I/Othread to update it

Slave_IO_State: Waiting for master to sendevent

Master_Host: 192.168.200.52

Master_User: rep

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: mysql-bin_52.000106

Read_Master_Log_Pos: 893

Relay_Log_File: mysqld-relay-bin-r2.000005

Relay_Log_Pos: 1183

Relay_Master_Log_File: mysql-bin_52.000106

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: 893

Relay_Log_Space: 1633

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: 2

Master_SSL_Crl:

Master_SSL_Crlpath:

Using_Gtid: No

Gtid_IO_Pos:

Retried_transactions: 0

Max_relay_log_size: 104857600

Executed_log_entries: 28

Slave_received_heartbeats: 4

Slave_heartbeat_period: 1800.000

Gtid_Slave_Pos:

2 rows in set (0.00 sec)

#单个通道初始化

MariaDB [r1]> reset slave 'r1' all;

ERROR 1198 (HY000): This operation cannot be performed as youhave a running slave 'r1'; run STOP SLAVE 'r1' first

MariaDB [r1]> stop slave 'r1';

Query OK, 0 rows affected (0.03 sec)

MariaDB [r1]> reset slave 'r1' all;

Query OK, 0 rows affected (0.04 sec)

MariaDB [r1]> stop slave 'r2';

Query OK, 0 rows affected (0.02 sec)

MariaDB [r1]> reset slave 'r2' all;

Query OK, 0 rows affected (0.02 sec)

MariaDB [r1]> show allslaves status\G;

Empty set (0.00 sec)

#所有通道初始化

MariaDB [r1]> stop allslaves;

Query OK, 0 rows affected, 2 warnings (0.05 sec)

MariaDB [r1]> show warnings;

+-------+------+--------------------+

| Level | Code |Message |

+-------+------+--------------------+

| Note | 1938 | SLAVE 'r2'stopped |

| Note | 1938 | SLAVE 'r1'stopped |

+-------+------+--------------------+

2 rows in set (0.00 sec)

MariaDB [r1]> reset slave all; #执行时候发现只能让r1初始化，不能初始化r2。所以初始化还是要单通道执行。

总结：

经过上面的测试，实现了多个主实例的数据同步到一个从实例，这个就可以把集中做分析的数据表同步到一起进行分析处理，大大减少了数据的中间处理时间和安全，这里还有一点特别注意的是，在同步数据库的时候可以用过滤选项（Replicate_Do_Table、Replicate_Ignore_Table、Replicate_Wild_Do_Table、Replicate_Wild_Ignore_Table），看着需要同步自己需要的表，不需要把没必要的也同步过来。

更多信息见：

https://mariadb.com/kb/en/mariadb/documentation/replication/standard-replication/multi-source-replication/

http://www.penglixun.com/tech/database/diy_multi_master_replication.html

原文链接:http://www.cnblogs.com/zhoujinyi/p/4102984.html