大纲

一、主从复制复制原理

二、主从复制的作用及复制类型

三、MySQL5.5异步复制的实现

四、MySQL5.5半同步复制的实现

五、MySQL复制过滤功能的实现




一、主从复制原理

mysql 设置lock wait time MySQL 设置主从过滤_mysql

工作原理

1、当Master接收到了一个写请求,处理写请求,将结果保存至磁盘中,并且会将此操作记录到二进制日志文件中

2、Slave会从Master的二进制日志中读取其中的事件保存至本地的中继日志中

3、Slave会启动一个线程来逐条读取中继日志中的事件并应用于本地的


二、主从复制的作用及复制类型

复制的作用

  • 辅助实现备份
  • 提供类似高可用的机制
  • 异地容灾
  • scale out:分摊负载,如实现读写分离

复制类型


  • 基于语句(statement)复制优点是基于语句的复制的二进制日志可以很好的进行压缩,而且日志的数据量也较小,缺点是基于语句的复制必须是串行化。
  • 基于行复制(Row-Based Replication),在二进制日志中记录下实际数据的改变,优点就是可以对任何语句都能正确工作,一些语句的效率更高,缺点就是二进制日志会很大,不能使用mysqlbinlog来查看二进制日志.
  • 混合类型(mixed)的复制,默认采用基于语句的复制,一旦发现基于语句的无法精确的复制时,就会采用基于行的复制.

三、MySQL5.5异步复制的实现

系统环境

CentOS5.8 x86_64

软件包

mysql-5.5.28-linux2.6-x86_64.tar.gz(二进制安装包)



配置主从复制的基本步骤

  • master:启用二进制日志、惟一server-id、具有复制权限的用户(REQUIRE SSL)
  • slave:启用中继日志、惟一server-id、连接主服务器并启动复制线程(IO_THREAD, SQL_THREAD)


1、Master安装并配置MySQL

数据目录底层最好是个逻辑卷,我这里就不再演示逻辑卷的创建了,我的博文中有,此处没有使用逻辑卷

准备数据目录并添加mysql用户
[root@Master ~]# mkdir -pv /mydata/data
mkdir: created directory `/mydata'
mkdir: created directory `/mydata/data'
[root@Master ~]# groupadd -g 3306 mysql
[root@Master ~]# useradd -u 3306 -g mysql -M -s /sbin/nologin -d /mydata/data/ mysql
[root@Master ~]# chown -R mysql.mysql /mydata/data/

解压并初始化mysql
[root@Master ~]# cd /tmp/
[root@Master tmp]# tar xf mysql-5.5.28-linux2.6-x86_64.tar.gz  -C /usr/local/
[root@Master tmp]# cd /usr/local/
[root@Master local]# ln -sv mysql-5.5.28-linux2.6-x86_64 mysql
create symbolic link `mysql' to `mysql-5.5.28-linux2.6-x86_64'
[root@Master local]# cd mysql
[root@Master mysql]# chown -R root.mysql ./*
[root@Master mysql]# ll
total 132
drwxr-xr-x  2 root mysql  4096 Jan 15 15:18 bin
-rw-r--r--  1 root mysql 17987 Aug 29  2012 COPYING
drwxr-xr-x  4 root mysql  4096 Jan 10 12:01 data
drwxr-xr-x  2 root mysql  4096 Jan 15 15:17 docs
drwxr-xr-x  3 root mysql  4096 Jan 15 15:18 include
-rw-r--r--  1 root mysql  7604 Aug 29  2012 INSTALL-BINARY
drwxr-xr-x  3 root mysql  4096 Jan 15 15:18 lib
drwxr-xr-x  4 root mysql  4096 Jan 10 12:02 man
drwxr-xr-x 10 root mysql  4096 Jan 15 15:18 mysql-test
-rw-r--r--  1 root mysql  2552 Aug 29  2012 README
drwxr-xr-x  2 root mysql  4096 Jan 15 15:18 scripts
drwxr-xr-x 27 root mysql  4096 Jan 15 15:18 share
drwxr-xr-x  4 root mysql  4096 Jan 15 15:18 sql-bench
drwxr-xr-x  2 root mysql  4096 Jan 15 15:18 support-files

[root@Master mysql]# scripts/mysql_install_db --user=mysql --datadir=/mydata/data/
Installing MySQL system tables...
OK
Filling help tables...
OK

To start mysqld at boot time you have to copy
support-files/mysql.server to the right place for your system

PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:

./bin/mysqladmin -u root password 'new-password'
./bin/mysqladmin -u root -h Master password 'new-password'

Alternatively you can run:
./bin/mysql_secure_installation

which will also give you the option of removing the test
databases and anonymous user created by default.  This is
strongly recommended for production servers.

See the manual for more instructions.

You can start the MySQL daemon with:
cd . ; ./bin/mysqld_safe &

You can test the MySQL daemon with mysql-test-run.pl
cd ./mysql-test ; perl mysql-test-run.pl

Please report any problems with the ./bin/mysqlbug script!

复制配置文件与服务启动脚本
[root@Master mysql]# cp support-files/my-large.cnf /etc/my.cnf 
[root@Master mysql]# cp support-files/mysql.server /etc/rc.d/init.d/mysqld
[root@Master mysql]# chkconfig --add mysqld

修改配置文件增加或修改如下行
[root@Master mysql]# vim /etc/my.cnf 
[mysqld]
datadir = /mydata/data
innodb_file_per_table = 1
log-bin=master-bin
log-bin-index=master-bin.index

增加PATH环境变量
[root@Master mysql]# echo 'export PATH=$PATH:/usr/local/mysql/bin' > /etc/profile.d/mysql.sh
[root@Master mysql]# . /etc/profile.d/mysql.sh

启动服务并创建复制用户
[root@Master mysql]# service mysqld start
Starting MySQL....                                         [  OK  ]
[root@Master mysql]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.28-log MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> GRANT REPLICATION SLAVE ON *.* TO 'repuser'@'172.16.%.%' IDENTIFIED BY 'repuser';
Query OK, 0 rows affected (0.34 sec)

mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.02 sec)

mysql> \q
Bye

将mysql的二进制包和配置文件拷贝至从节点
[root@Master mysql]# scp  /tmp/mysql-5.5.28-linux2.6-x86_64.tar.gz Slave:/tmp
mysql-5.5.28-linux2.6-x86_64.tar.gz                       100%  178MB   7.4MB/s   00:24
[root@Master mysql]# scp /etc/my.cnf Slave:/etc/
my.cnf                                          100% 4745     4.6KB/s   00:00


2、Slave安装并配置MySQL



准备数据目录并添加mysql用户
[root@Slave ~]# mkdir -pv /mydata/data
mkdir: created directory `/mydata'
mkdir: created directory `/mydata/data'
[root@Slave ~]# groupadd -g 3306 mysql
[root@Slave ~]# useradd -u 3306 -g mysql -M -s /sbin/nologin -d /mydata/data/ mysql
[root@Slave ~]# chown -R mysql.mysql /mydata/data/

解压并初始化mysql
[root@Slave ~]# cd /tmp/
[root@Slave tmp]# tar xf mysql-5.5.28-linux2.6-x86_64.tar.gz  -C /usr/local/
[root@Slave tmp]# cd /usr/local/
[root@Slave local]# ln -sv mysql-5.5.28-linux2.6-x86_64 mysql
create symbolic link `mysql' to `mysql-5.5.28-linux2.6-x86_64'
[root@Slave local]# cd mysql
[root@Slave mysql]# chown -R root.mysql ./*
[root@Slave mysql]# ll
total 132
drwxr-xr-x  2 root mysql  4096 Jan 15 15:45 bin
-rw-r--r--  1 root mysql 17987 Aug 29  2012 COPYING
drwxr-xr-x  4 root mysql  4096 Jan 10 11:15 data
drwxr-xr-x  2 root mysql  4096 Jan 15 15:45 docs
drwxr-xr-x  3 root mysql  4096 Jan 15 15:46 include
-rw-r--r--  1 root mysql  7604 Aug 29  2012 INSTALL-BINARY
drwxr-xr-x  3 root mysql  4096 Jan 15 15:46 lib
drwxr-xr-x  4 root mysql  4096 Jan 10 11:16 man
drwxr-xr-x 10 root mysql  4096 Jan 15 15:46 mysql-test
-rw-r--r--  1 root mysql  2552 Aug 29  2012 README
drwxr-xr-x  2 root mysql  4096 Jan 15 15:46 scripts
drwxr-xr-x 27 root mysql  4096 Jan 15 15:46 share
drwxr-xr-x  4 root mysql  4096 Jan 15 15:46 sql-bench
drwxr-xr-x  2 root mysql  4096 Jan 15 15:46 support-files

[root@Slave mysql]# scripts/mysql_install_db --user=mysql --datadir=/mydata/data/
Installing MySQL system tables...
OK
Filling help tables...
OK

To start mysqld at boot time you have to copy
support-files/mysql.server to the right place for your system

PLEASE REMEMBER TO SET A PASSWORD FOR THE MySQL root USER !
To do so, start the server, then issue the following commands:

./bin/mysqladmin -u root password 'new-password'
./bin/mysqladmin -u root -h Slave password 'new-password'

Alternatively you can run:
./bin/mysql_secure_installation

which will also give you the option of removing the test
databases and anonymous user created by default.  This is
strongly recommended for production servers.

See the manual for more instructions.

You can start the MySQL daemon with:
cd . ; ./bin/mysqld_safe &

You can test the MySQL daemon with mysql-test-run.pl
cd ./mysql-test ; perl mysql-test-run.pl

Please report any problems with the ./bin/mysqlbug script!

复制服务启动脚本
[root@Slave mysql]# cp support-files/mysql.server /etc/rc.d/init.d/mysqld
[root@Slave mysql]# chkconfig --add mysqld

修改配置文件做如下修改
[root@Slave mysql]# vim /etc/my.cnf 
[mysqld]
这两行要注释掉,从节点不开启二进制日志功能
#log-bin=Slave-bin                    
#log-bin-index=Slave-bin.index

修改server_id,不能与主节点重复,要全局唯一
server-id       = 11

增加中继日志功能
relay-log = relay-log
relay-log-index = relay-log.index

使从节点只读,不过此参数对具有SUPER权限的用户无效
read-only = ON

增加PATH环境变量并使之生效
[root@Slave mysql]# echo 'export PATH=$PATH:/usr/local/mysql/bin' > /etc/profile.d/mysql.sh
[root@Slave mysql]# . /etc/profile.d/mysql.sh

启动服务
[root@Slave ~]# service mysqld start
Starting MySQL....                                         [  OK  ]


3、启动Slave上的复制功能


首次在Master上查看当前二进制日志所处的position
[root@Master mysql]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.5.28-log MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW MASTER STATUS; 
+-------------------+----------+--------------+------------------+
| File              | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+-------------------+----------+--------------+------------------+
| master-bin.000001 |      337 |              |                  | 
+-------------------+----------+--------------+------------------+
1 row in set (0.00 sec)

mysql> SHOW BINLOG EVENTS IN 'master-bin.000001';
+-------------------+-----+-------------+-----------+-------------+----------------------------------------------------------------------------------+
| Log_name          | Pos | Event_type  | Server_id | End_log_pos | Info                                                                             |
+-------------------+-----+-------------+-----------+-------------+----------------------------------------------------------------------------------+
| master-bin.000001 |   4 | Format_desc |         1 |         107 | Server ver: 5.5.28-log, Binlog ver: 4                                            | 
| master-bin.000001 | 107 | Query       |         1 |         262 | GRANT REPLICATION SLAVE ON *.* TO 'repuser'@'172.16.%.%' IDENTIFIED BY 'repuser' | 
| master-bin.000001 | 262 | Query       |         1 |         337 | FLUSH PRIVILEGES                                                                 | 
+-------------------+-----+-------------+-----------+-------------+----------------------------------------------------------------------------------+
3 rows in set (0.02 sec)

mysql> \q
Bye

再在Slave上启动复制功能
[root@Slave mysql]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.5.28 MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> CHANGE MASTER TO MASTER_HOST='172.16.1.101',MASTER_PORT=3306,MASTER_USER='repuser',MASTER_PASSWORD='repuser',MASTER_LOG_FILE='master-bin.000001',MASTER_LOG_POS=337;
Query OK, 0 rows affected (0.18 sec)

mysql> SHOW SLAVE STATUS\G
*************************** 1. row ***************************
               Slave_IO_State: 
                  Master_Host: 172.16.1.101
                  Master_User: repuser
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: master-bin.000001
          Read_Master_Log_Pos: 337
               Relay_Log_File: relay-log.000001
                Relay_Log_Pos: 4
        Relay_Master_Log_File: master-bin.000001
             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: 337
              Relay_Log_Space: 107
              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
1 row in set (0.00 sec)

mysql> START SLAVE;
Query OK, 0 rows affected (0.49 sec)

mysql> SHOW SLAVE STATUS\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 172.16.1.101
                  Master_User: repuser
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: master-bin.000001
          Read_Master_Log_Pos: 337
               Relay_Log_File: relay-log.000002
                Relay_Log_Pos: 254
        Relay_Master_Log_File: master-bin.000001
             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: 337
              Relay_Log_Space: 404
              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
1 row in set (0.04 sec)

4、测试复制功能

首先在主节点上创建一个测试库
[root@Master mysql]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.5.28-log MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema | 
| mysql              | 
| performance_schema | 
| test               | 
+--------------------+
4 rows in set (0.28 sec)

mysql> CREATE DATABASE mydb;
Query OK, 1 row affected (0.10 sec)

mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema | 
| mydb               | 
| mysql              | 
| performance_schema | 
| test               | 
+--------------------+
5 rows in set (0.01 sec)

再在从节点上查看是否有此库
[root@Slave mysql]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.5.28 MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW SLAVE STATUS\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 172.16.1.101
                  Master_User: repuser
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: master-bin.000001
          Read_Master_Log_Pos: 420                        # 可以看到已经读取到420位置了
               Relay_Log_File: relay-log.000002
                Relay_Log_Pos: 337
        Relay_Master_Log_File: master-bin.000001
             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: 420                        # 同样执行到了420位置
              Relay_Log_Space: 487
              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
1 row in set (0.01 sec)

mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema | 
| mydb               | 
| mysql              | 
| performance_schema | 
| test               | 
+--------------------+
5 rows in set (0.00 sec)
可以看到主从复制效果已然实现

查看从节点的错误日志,发现复制相关的日志信息也会记录到错误日志中
[root@Slave mysql]# tail /mydata/data/Slave.err 
160115 15:55:06 InnoDB: 1.1.8 started; log sequence number 0
160115 15:55:07 [Note] Server hostname (bind-address): '0.0.0.0'; port: 3306
160115 15:55:07 [Note]   - '0.0.0.0' resolves to '0.0.0.0';
160115 15:55:07 [Note] Server socket created on IP: '0.0.0.0'.
160115 15:55:08 [Note] Event Scheduler: Loaded 0 events
160115 15:55:08 [Note] /usr/local/mysql/bin/mysqld: ready for connections.
Version: '5.5.28'  socket: '/tmp/mysql.sock'  port: 3306  MySQL Community Server (GPL)
160115 16:05:15 [Note] 'CHANGE MASTER TO executed'. Previous state master_host='', master_port='3306', master_log_file='', master_log_pos='4'. New state master_host='172.16.1.101', master_port='3306', master_log_file='master-bin.000001', master_log_pos='337'.
160115 16:10:46 [Note] Slave I/O thread: connected to master 'repuser@172.16.1.101:3306',replication started in log 'master-bin.000001' at position 337
160115 16:10:46 [Note] Slave SQL thread initialized, starting replication in log 'master-bin.000001' at position 337, relay log './relay-log.000001' position: 4

四、MySQL5.5半同步复制的实现

1、设置Master,安装插件并启用


[root@Master ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.5.28-log MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_master.so';  
Query OK, 0 rows affected (0.10 sec)

mysql> SET GLOBAL rpl_semi_sync_master_enabled = 1;  
Query OK, 0 rows affected (0.00 sec)

mysql> SET GLOBAL rpl_semi_sync_master_timeout = 1000;  
Query OK, 0 rows affected (0.00 sec)

mysql> \q
Bye

将两个服务器变量写入配置文件中
[root@Master ~]# vim /etc/my.cnf
[mysqld]
rpl_semi_sync_master_enabled=1
rpl_semi_sync_master_timeout=1000

查看从服务器上的semi_sync是否开启
[root@Master ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.5.28-log MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW GLOBAL STATUS LIKE 'rpl_semi%';
+--------------------------------------------+-------+
| Variable_name                              | Value |
+--------------------------------------------+-------+
| Rpl_semi_sync_master_clients               | 1     |     # 值为1证明主从半同步复制连接成功
| Rpl_semi_sync_master_net_avg_wait_time     | 0     | 
| Rpl_semi_sync_master_net_wait_time         | 0     | 
| Rpl_semi_sync_master_net_waits             | 0     | 
| Rpl_semi_sync_master_no_times              | 1     | 
| Rpl_semi_sync_master_no_tx                 | 1     | 
| Rpl_semi_sync_master_status                | ON    | 
| Rpl_semi_sync_master_timefunc_failures     | 0     | 
| Rpl_semi_sync_master_tx_avg_wait_time      | 0     | 
| Rpl_semi_sync_master_tx_wait_time          | 0     | 
| Rpl_semi_sync_master_tx_waits              | 0     | 
| Rpl_semi_sync_master_wait_pos_backtraverse | 0     | 
| Rpl_semi_sync_master_wait_sessions         | 0     | 
| Rpl_semi_sync_master_yes_tx                | 0     | 
+--------------------------------------------+-------+
14 rows in set (0.07 sec)



2、设置Slave,安装插件并启用



[root@Slave ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.5.28 MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> INSTALL PLUGIN rpl_semi_sync_slave SONAME 'semisync_slave.so'; 
Query OK, 0 rows affected (0.06 sec)

mysql> SET GLOBAL rpl_semi_sync_slave_enabled = 1; 
Query OK, 0 rows affected (0.00 sec)

mysql> STOP SLAVE IO_THREAD; START SLAVE IO_THREAD;
Query OK, 0 rows affected (0.03 sec)

mysql> \q
Bye

将上面那个服务器变量写入配置文件中
[root@Slave ~]# vim /etc/my.cnf
[mysqld]
rpl_semi_sync_slave_enabled=1

查看从服务器上的semi_sync是否开启
[root@Slave ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 7
Server version: 5.5.28 MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW GLOBAL STATUS LIKE 'rpl_semi%';
+----------------------------+-------+
| Variable_name              | Value |
+----------------------------+-------+
| Rpl_semi_sync_slave_status | ON    | 
+----------------------------+-------+
1 row in set (0.00 sec)




3、测试半同步效果

[root@Master ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 6
Server version: 5.5.28-log MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW GLOBAL STATUS LIKE 'rpl_semi%';
+--------------------------------------------+-------+
| Variable_name                              | Value |
+--------------------------------------------+-------+
| Rpl_semi_sync_master_clients               | 1     | 
| Rpl_semi_sync_master_net_avg_wait_time     | 15488 | 
| Rpl_semi_sync_master_net_wait_time         | 15488 | 
| Rpl_semi_sync_master_net_waits             | 1     | 
| Rpl_semi_sync_master_no_times              | 1     | 
| Rpl_semi_sync_master_no_tx                 | 1     | 
| Rpl_semi_sync_master_status                | ON    | 
| Rpl_semi_sync_master_timefunc_failures     | 0     | 
| Rpl_semi_sync_master_tx_avg_wait_time      | 23055 | 
| Rpl_semi_sync_master_tx_wait_time          | 23055 | 
| Rpl_semi_sync_master_tx_waits              | 1     | 
| Rpl_semi_sync_master_wait_pos_backtraverse | 0     | 
| Rpl_semi_sync_master_wait_sessions         | 0     | 
| Rpl_semi_sync_master_yes_tx                | 1     | 
+--------------------------------------------+-------+
14 rows in set (0.00 sec)

mysql> CREATE DATABASE testdb;
Query OK, 1 row affected (0.21 sec)            # 注意这个时间

此时关掉从节点的IO_Thread
[root@Slave ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 5.5.28 MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> STOP SLAVE IO_Thread;
Query OK, 0 rows affected (0.09 sec)

再来创建个hellodb库
mysql> CREATE DATABASE hellodb;
Query OK, 1 row affected (1.01 sec)            # 我们设置的超时时长为1s

再启用Slave的IO_Thread
mysql> START SLAVE IO_Thread;
Query OK, 0 rows affected (0.00 sec)

mysql> \q
Bye

五、MySQL复制过滤功能的实现


建议在从服务器上设置,因为在主服务器上设置replicate_do_db或replicate_ignore_db时,
任何不涉及到数据库相关的写操作都不会被记录到二进制日志当中,
那么会造成主服务器上的二进制日志不完整,
一旦将来数据库崩溃,不能做及时点还原,所以建议在从服务器上设置,尽管会浪费大量网络IO和磁盘IO

要只想复制某个库,只需在从服务器的my.cnf配置文件中[mysqld]段中加一行replicate_do_db = db_name即可;
若只想复制某张表,只需在从服务器的my.cnf配置文件中[mysqld]段中加一行replicate_do_db = tb_name即可;
若想使用通配符,则使用replicate_wild_do_table = db[%_],%表示任意长度任意字符,_表示任意单个字符;

从服务器设置完成,重启mysql服务器,然后进入交互式模式,执行mysql> SHOW SLAVE STATUS\G
查看Replicate_Do_DB这一字段,即可验证配置是否生效,具体操作过程如下

首先编辑从服务器的配置文件
[root@Slave ~]# vim /etc/my.cnf 
[mysqld]
replicate-do-db = mydb            # 表示只复制这一个库,如想复制多个,此指令可以使用多次

重启Slave服务器
[root@Slave ~]# service mysqld restart
Shutting down MySQL...                                     [  OK  ]
Starting MySQL...                                          [  OK  ]

然后连接Slave,查看状态信息
[root@Slave ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.5.28 MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW SLAVE STATUS\G
*************************** 1. row ***************************
               Slave_IO_State: Waiting for master to send event
                  Master_Host: 172.16.1.101
                  Master_User: repuser
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: master-bin.000002
          Read_Master_Log_Pos: 358
               Relay_Log_File: relay-log.000009
                Relay_Log_Pos: 254
        Relay_Master_Log_File: master-bin.000002
             Slave_IO_Running: Yes
            Slave_SQL_Running: Yes
              Replicate_Do_DB: mydb                        # 可以看到指令生效了
          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: 358
              Relay_Log_Space: 404
              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
1 row in set (0.00 sec)

接下来我们在主服务器上创建三个库,测试一下
[root@Master ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 11
Server version: 5.5.28-log MySQL Community Server (GPL)

Type 'help;' or '\h' for help. Type '\c' to clear the buffer.

mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema | 
| mysql              | 
| performance_schema | 
| test               | 
+--------------------+
4 rows in set (0.00 sec)

mysql> CREATE DATABASE hellodb;
Query OK, 1 row affected (0.01 sec)

mysql> CREATE DATABASE testdb;
Query OK, 1 row affected (0.01 sec)

mysql> CREATE DATABASE mydb;
Query OK, 1 row affected (0.00 sec)

再在从服务器上查看是否有这三个库
mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema |     
| mydb               |                     # 可以看到只有mydb,因为我们定义了只复制mydb库
| mysql              | 
| performance_schema | 
| test               | 
+--------------------+
5 rows in set (0.00 sec)
如此即可实现mysql的复制过滤功能








转载于:https://blog.51cto.com/soysauce93/1735321