MySQL系列详解九：MySQL级联复制演示-技术流ken

前言

级联复制就是master服务器，只给后端一台slave服务器同步数据，然后这个slave服务器在向后端的所有slave服务器同步数据，这样就可以降低master服务器的写压力，和复制数据的网络IO。

实现级联复制演示

准备

主服务器IP:10.220.5.137

从1服务器IP:10.220.5.138

从2服务器IP:10.220.5.139

配置主服务器

开启二进制日志

mysql> show global variables like '%log_bin%';
+---------------------------------+--------------------------------------------+
| Variable_name                   | Value                                      |
+---------------------------------+--------------------------------------------+
| log_bin                         | ON                                         |
| log_bin_basename                | /data/mysql/mysql3306/logs/mysql-bin       |
| log_bin_index                   | /data/mysql/mysql3306/logs/mysql-bin.index |
| log_bin_trust_function_creators | ON                                         |
| log_bin_use_v1_row_events       | OFF                                        |
+---------------------------------+--------------------------------------------+
 rows in set (0.01 sec)

创建用于复制的用户

mysql> grant replication slave on *.* to 'ken'@'%' identified by 'xx';

查看主服务器端状态

需要查看现在主服务器端在哪个日志文件写入日志以及现在的位置

mysql> show master status\G
*************************** . row ***************************
             File: mysql-bin.
         Position:
     Binlog_Do_DB:
 Binlog_Ignore_DB:
Executed_Gtid_Set: 987ac782-d7b8-11e8-a462-000c292218ec:-,
c01b1811-d7b3-11e8--000c29492f7b:-
 row in set (0.00 sec)

配置从1服务器

与主服务器端建立连接

MySQL [(none)]> change master to master_host='10.220.5.137',master_user='ken',master_passowrd='xx',master_log_file='mysql-bin.000012',master_log_pos=;

启动slave

MySQL [(none)]> start slave;

查看连接状态

要确认IO以及SQL线程成功开启

ySQL [(none)]> show slave status\G
*************************** . row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 10.220.5.137
                  Master_User: ken
                  Master_Port:
                Connect_Retry:
              Master_Log_File: mysql-bin.
          Read_Master_Log_Pos:
               Relay_Log_File: relay-bin.
                Relay_Log_Pos:
        Relay_Master_Log_File: mysql-bin.
             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:
                   Last_Error:
                 Skip_Counter:
          Exec_Master_Log_Pos:
              Relay_Log_Space:
              Until_Condition: None
               Until_Log_File:
                Until_Log_Pos:
           Master_SSL_Allowed: No
           Master_SSL_CA_File:
           Master_SSL_CA_Path:
              Master_SSL_Cert:
            Master_SSL_Cipher:
               Master_SSL_Key:
        Seconds_Behind_Master:
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno:
                Last_IO_Error:
               Last_SQL_Errno:
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id:
                  Master_UUID: 987ac782-d7b8-11e8-a462-000c292218ec
             Master_Info_File: /data/mysql/mysql3306/data/master.info
                    SQL_Delay:
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
           Master_Retry_Count:
                  Master_Bind:
      Last_IO_Error_Timestamp:
     Last_SQL_Error_Timestamp:
               Master_SSL_Crl:
           Master_SSL_Crlpath:
           Retrieved_Gtid_Set: 987ac782-d7b8-11e8-a462-000c292218ec:-
            Executed_Gtid_Set: 987ac782-d7b8-11e8-a462-000c292218ec:-,
c01b1811-d7b3-11e8--000c29492f7b:-
                Auto_Position:
         Replicate_Rewrite_DB:
                 Channel_Name:
           Master_TLS_Version:
 row in set (0.00 sec)

查看从1服务器端状态

需要查看现在从1服务器端在哪个日志文件写入日志以及现在的位置

mysql> show master status\G
*************************** 1. row ***************************
             File: mysql-bin.000007
         Position: 2057
     Binlog_Do_DB:
 Binlog_Ignore_DB:
Executed_Gtid_Set: 987ac782-d7b8-11e8-a462-000c292218ec:1-13,
c01b1811-d7b3-11e8-8698-000c29492f7b:3-7
1 row in set (0.00 sec)

配置从2服务器端

与从1服务器端建立连接

MySQL [(none)]> change master to master_host='10.220.5.138',master_user='ken',master_passowrd='xx',master_log_file='mysql-bin.000007',master_log_pos=2057;

启动slave

MySQL [(none)]> start slave;

查看连接状态

要确认IO以及SQL线程成功开启

ySQL [(none)]> show slave status\G
*************************** . row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 10.220.5.138
                  Master_User: ken
                  Master_Port:
                Connect_Retry:
              Master_Log_File: mysql-bin.
          Read_Master_Log_Pos:
               Relay_Log_File: relay-bin.
                Relay_Log_Pos:
        Relay_Master_Log_File: mysql-bin.
             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:
                   Last_Error:
                 Skip_Counter:
          Exec_Master_Log_Pos:
              Relay_Log_Space:
              Until_Condition: None
               Until_Log_File:
                Until_Log_Pos:
           Master_SSL_Allowed: No
           Master_SSL_CA_File:
           Master_SSL_CA_Path:
              Master_SSL_Cert:
            Master_SSL_Cipher:
               Master_SSL_Key:
        Seconds_Behind_Master:
Master_SSL_Verify_Server_Cert: No
                Last_IO_Errno:
                Last_IO_Error:
               Last_SQL_Errno:
               Last_SQL_Error:
  Replicate_Ignore_Server_Ids:
             Master_Server_Id:
                  Master_UUID: 987ac782-d7b8-11e8-a462-000c292218ec
             Master_Info_File: /data/mysql/mysql3306/data/master.info
                    SQL_Delay:
          SQL_Remaining_Delay: NULL
      Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
           Master_Retry_Count:
                  Master_Bind:
      Last_IO_Error_Timestamp:
     Last_SQL_Error_Timestamp:
               Master_SSL_Crl:
           Master_SSL_Crlpath:
           Retrieved_Gtid_Set: 987ac782-d7b8-11e8-a462-000c292218ec:-
            Executed_Gtid_Set: 987ac782-d7b8-11e8-a462-000c292218ec:-,
c01b1811-d7b3-11e8--000c29492f7b:-
                Auto_Position:
         Replicate_Rewrite_DB:
                 Channel_Name:
           Master_TLS_Version:
 row in set (0.00 sec)

测试

现在从2服务器是从从1服务器端同步的数据，没有直接和主服务器端建立连接，而是通过从1间接的进行了连接。现在在主服务器端建库建表，查看从2服务器是否有主服务器端的库和表。

主服务器建库建表

mysql> create database ken6;              <<建立数据库ken6
mysql> use ken6;                          <<切换至ken6
Database changed
mysql> create table ken(id int);          <<创建表ken
Query OK,  rows affected (0.02 sec)

mysql> insert into ken values (),();    <<插入数据
Query OK,  rows affected (0.01 sec)
Records:   Duplicates:   Warnings: 

mysql> select * from ken;                <<查看刚才插入的数据
+------+
| id   |
+------+
|     |
|     |
+------+
 rows in set (0.00 sec)

在从1服务器端查看已经同步过来了主服务器端新建的库和表

MySQL [(none)]> select * from ken6.ken;
+------+
| id   |
+------+
|     |
|     |
+------+

在从2检查发现也已经同步过来了主服务器端的库和表，这样就完后了级联复制的操作

MySQL [(none)]> select * from ken6.ken;
+------+
| id   |
+------+
|     |
|     |
+------+
 rows in set (0.00 sec)