当前位置:首页 >> 数据库

mariadb的主从复制、主主复制、半同步复制配置详解

主从服务器的时间要同步,数据库版本最好是一致的,以免造成函数处理、日志读取、日志解析等发生异常。

以下三个主从复制的设置是独立的。

注意防火墙和selinux的影响。

1、简单主从复制的实现

(1)主服务器的配置

1)安装mariadb-server

[root@localhost ~]# yum -y install mariadb-server

2)编辑/etc/my.cnf文件

[root@localhost ~]# vim /etc/my.cnf

    在[mysqld]段的最后添加以下内容

    skip_name_resolve = ON
    innodb_file_per_table = ON
    server-id = 1 (id号不能跟从服务器相同)
    log-bin = master-log (自定义二进制日志文件名)

3)授权可以复制本地数据库信息的主机

[root@localhost ~]# systemctl start mariadb.service (启动mariadb server)

[root@localhost ~]# mysql
 MariaDB [(none)]> grant replication slave,replication client on *.* to 'repluser'@'10.1.51.%' identified by 'replpasswd';
 MariaDB [(none)]> flush privileges;

MariaDB [(none)]> show master status\G (查看主服务器的状态信息,在从服务器中要用到)
*************************** 1. row ***************************
   File: master-log.000003 (正在使用的二进制日志文件)
  Position: 497 (所处的位置)
 Binlog_Do_DB: 
Binlog_Ignore_DB:

(2)从服务器的配置

1)安装mariadb-server

[root@localhost ~]# yum -y install mariadb-server

2)编辑/etc/my.cnf文件

[root@localhost ~]# vim /etc/my.cnf

    在[mysqld]段的最后添加以下内容

    skip_name_resolve = ON
    innodb_file_per_table = ON
    server-id = 2 (id号不能跟主服务器相同)
    relay-log = slave-log (自定义二进制日志文件名)

3)设置要从哪个主服务器的那个位置开始同步

[root@localhost ~]# systemctl start mariadb.service

[root@localhost ~]# mysql
 MariaDB [(none)]> change master to master_host='10.1.51.60',master_user='repluser',master_password='replpasswd',master_log_file='master-log.000003',master_log_pos=497;

MariaDB [(none)]> start slave; (启动复制功能)
MariaDB [(none)]> show slave status\G (查看从服务器的状态,下面显示的是部分内容)
 Master_Host: 10.1.51.60
 Master_User: repluser
 Master_Port: 3306
 Connect_Retry: 60
 Master_Log_File: master-log.000003
 Read_Master_Log_Pos: 497
 Relay_Log_File: slave-log.000002
 Relay_Log_Pos: 530
 Relay_Master_Log_File: master-log.000003
 Slave_IO_Running: Yes 
 Slave_SQL_Running: Yes
 Master_Server_Id: 1

(3)测试

1)在主服务器导入事先准备好的数据库

[root@localhost ~]# mysql < hellodb.sql

2)在从服务器查看是否同步

MariaDB [(none)]> show databases;
+--------------------+
| Database   |
+--------------------+
| information_schema |
| hellodb   |(数据库已经同步)
| mysql    |
| performance_schema |
| test    |
+--------------------+
MariaDB [(none)]> use hellodb;
MariaDB [hellodb]> show tables; (hellodb数据库的表也是同步的)
+-------------------+
| Tables_in_hellodb |
+-------------------+
| classes   |
| coc    |
| courses   |
| scores   |
| students   |
| teachers   |
| toc    |
+-------------------+

2、双主复制的实现

(1)服务器1的配置

1)安装mariadb-server

[root@localhost ~]# yum -y install mariadb-server

2)编辑/etc/my.cnf文件

[root@localhost ~]# vim /etc/my.cnf

    在[mysqld]段的最后添加以下内容

    skip_name_resolve = ON
    innodb_file_per_table = ON
    server-id = 1 (id号不能跟从服务器相同)
    log-bin = master-log (自定义主服务器的二进制日志文件名)
    relay-log = slave-log (自定义从服务器的二进制日志文件名)
    auto_increment_offset = 1
    auto_increment_increment = 2

3)在服务器2上查看的master状态

MariaDB [(none)]> show master status\G
*************************** 1. row ***************************
   File: master-log.000003
  Position: 422
 Binlog_Do_DB: 
Binlog_Ignore_DB:

4)启动mariadb server并进行如下配置

[root@localhost ~]# systemctl start mariadb.service

[root@localhost ~]# mysql

 MariaDB [(none)]> grant replication slave,replication client on *.* to 'repluser'@'10.1.51.%' identified by 'replpasswd';

 MariaDB [(none)]> change master to master_host='10.1.51.50',master_user='repluser',master_password='replpasswd',master_log_file='master-log.000003',master_log_pos=422;

 MariaDB [(none)]> start slave;

 MariaDB [(none)]> SHOW SLAVE STATUS\G (仅是部分内容)
  Master_Host: 10.1.51.50
  Master_User: repluser
  Master_Port: 3306
  Connect_Retry: 60
  Master_Log_File: master-log.000003
  Read_Master_Log_Pos: 422
  Relay_Log_File: slave-log.000002
  Relay_Log_Pos: 530
  Relay_Master_Log_File: master-log.000003
  Slave_IO_Running: Yes
  Slave_SQL_Running: Yes
  Master_Server_Id: 2

(2)服务器2的配置

1)安装mariadb-server

[root@localhost ~]# yum -y install mariadb-server

2)编辑/etc/my.cnf文件

[root@localhost ~]# vim /etc/my.cnf
    skip_name_resolve = ON
    innodb_file_per_table = ON
    server-id = 2
    relay-log = slave-log
    lob-bin = master-log
    auto_increment_offset = 2
    auto_increment_increment = 2

3)在服务器1查看master状态

MariaDB [(none)]> show master status\G
*************************** 1. row ***************************
            File: master-log.000003
        Position: 245
    Binlog_Do_DB:
Binlog_Ignore_DB:

4)启动mariadb server并配置

[root@localhost ~]# systemctl start mariadb.service

[root@localhost ~]# mysql

 MariaDB [(none)]> grant replication slave,replication client on *.* to 'repluser'@'10.1.51.%' identified by 'replpasswd';

 MariaDB [(none)]> change master to master_host='10.1.51.60',master_user='repluser',master_password='replpasswd',master_log_file='master-log.000003',master_log_pos=245;

 MariaDB [(none)]> start slave;

 MariaDB [(none)]> show slave status\G (仅是部分内容) 
  Master_Host: 10.1.51.60
  Master_User: repluser
  Master_Port: 3306
  Connect_Retry: 60
  Master_Log_File: master-log.000003
  Read_Master_Log_Pos: 422
  Relay_Log_File: slave-log.000003
  Relay_Log_Pos: 530
  Relay_Master_Log_File: master-log.000003
  Slave_IO_Running: Yes
  Slave_SQL_Running: Yes
  Master_Server_Id: 1

(3)测试

1)在任意一台服务器上创建mydb数据库

MariaDB [(none)]> create database mydb;

2)在另一台服务器上查看

MariaDB [(none)]> show databases;
+--------------------+
| Database   |
+--------------------+
| information_schema |
| mydb    |
| mysql    |
| performance_schema |
| test    |
+--------------------+

3、半同步复制的实现

(1)在主服务器上的配置

1)安装mariadb-server

[root@localhost ~]# yum -y install mariadb-server

2)编辑/etc/my.cnf

[root@localhost ~]# vim /etc/my.cnf
    skip_name_resolve = ON
    innodb_file_per_table = ON
    server-id = 1
    log-bin = master-log

3)授权可以复制本地数据库信息的主机

[root@localhost ~]# systemctl start mariadb.service (启动mariadb server)

[root@localhost ~]# mysql
 MariaDB [(none)]> grant replication slave,replication client on *.* to 'repluser'@'10.1.51.%' identified by 'replpasswd';
 MariaDB [(none)]> flush privileges;

MariaDB [(none)]> show master status\G (查看主服务器的状态信息,在从服务器中要用到)
*************************** 1. row ***************************
   File: master-log.000003 (正在使用的二进制日志文件)
  Position: 245 (所处的位置)
 Binlog_Do_DB: 
Binlog_Ignore_DB:

4)安装rpl semi sync_master插件,并启用

[root@localhost ~]# mysql

MariaDB [(none)]> install plugin rpl_semi_sync_master soname 'semisync_master.so';
MariaDB [(none)]> set global rpl_semi_sync_master_enabled = ON;

补充:

MariaDB [(none)]> show plugins;(可查看插件是否激活)
MariaDB [(none)]> show global variables like 'rpl_semi%';(可查看安装的插件是否启用)
MariaDB [(none)]> show global status like '%semi%';(可查看从服务器的个数,此时是0个)

(2)从服务器的配置

1)安装mariadb-server

[root@localhost ~]# yum -y install mariadb-server

2)编辑/etc/my.cnf文件

[root@localhost ~]# vim /etc/my.cnf

    在[mysqld]段的最后添加以下内容

    skip_name_resolve = ON
    innodb_file_per_table = ON
    server-id = 2 (id号不能跟主服务器相同)
    relay-log = slave-log (自定义二进制日志文件名)

3)设置要从哪个主服务器的那个位置开始同步

[root@localhost ~]# systemctl start mariadb.service

[root@localhost ~]# mysql

 MariaDB [(none)]> change master to master_host='10.1.51.60',master_user='repluser',master_password='replpasswd',master_log_file='master-log.000003',master_log_pos=245;

4)安装rpl semi sync_slave插件并启用

[root@localhost ~]# mysql 

 MariaDB [(none)]> install plugin rpl_semi_sync_slave soname 'semisync_slave.so';
 MariaDB [(none)]> set global rpl_semi_sync_slave_enabled = ON;
 MariaDB [(none)]> start slave;

完成上面配置后,可以在主服务器上查看半同步复制的相关信息,命令如下:

MariaDB [(none)]> show global status like '%semi%';
 Rpl_semi_sync_master_clients 1 (从服务器有一台)

(3)测试

测试以个人实际情况而定
1)在主服务器上导入事先准备好的数据库hellodb.sql

MariaDB [hellodb]> source /root/hellodb.sql;

2)在主服务器上查看半同步复制的状态

MariaDB [hellodb]> show master status;
+-------------------+----------+--------------+------------------+
| File    | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+-------------------+----------+--------------+------------------+
| master-log.000003 |  8102 |    |     |
+-------------------+----------+--------------+------------------+

MariaDB [hellodb]> show global status like '%semi%';
+--------------------------------------------+-------+
| Variable_name        | Value |
+--------------------------------------------+-------+
| Rpl_semi_sync_master_clients    | 1  |
| Rpl_semi_sync_master_net_avg_wait_time  | 1684 |
| Rpl_semi_sync_master_net_wait_time   | 60630 |
| Rpl_semi_sync_master_net_waits    | 36 |
| 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  | 1884 |
| Rpl_semi_sync_master_tx_wait_time   | 65965 |
| Rpl_semi_sync_master_tx_waits    | 35 |
| Rpl_semi_sync_master_wait_pos_backtraverse | 0  |
| Rpl_semi_sync_master_wait_sessions   | 0  |
| Rpl_semi_sync_master_yes_tx    | 35 |
+--------------------------------------------+-------+

3)在从服务器上查看是否同步

MariaDB [(none)]> show databases;
MariaDB [(none)]> use hellodb;
MariaDB [hellodb]> select * from students;

补充:基于上面的半同步复制配置复制的过滤器,复制过滤最好在从服务器上设置,步骤如下

(1)从服务器的配置

1)关闭mariadb server

[root@localhost ~]# systemctl stop mariadb.service

2)编辑/etc/my.cnf文件

[root@localhost ~]# vim /etc/my.cnf
 skip_name_resolve = ON
 innodb_file_per_table = ON
 server-id = 2
 relay-log = slave-log
 replicate-do-db = mydb (只复制mydb数据库的内容)

补充:常用的过滤选项如下

    Replicate_Do_DB=
    Replicate_Ignore_DB=
    Replicate_Do_Table=
    Replicate_Ignore_Table=
    Replicate_Wild_Do_Table=
    Replicate_Wild_Ignore_Table=

3)重启mariadb server

[root@localhost ~]# systemctl start mariadb.service

4)重启mariadb server后,半同步复制功能将被关闭,因此要重新启动

MariaDB [(none)]> show global variables like '%semi%';
+---------------------------------+-------+
| Variable_name     | Value |
+---------------------------------+-------+
| rpl_semi_sync_slave_enabled  | OFF |
| rpl_semi_sync_slave_trace_level | 32 |
+---------------------------------+-------+

MariaDB [(none)]> set global rpl_semi_sync_slave_enabled = ON;
MariaDB [(none)]> stop slave;(需先关闭从服务器复制功能再重启)
MariaDB [(none)]> start slave;

(2)测试

1)主服务器上的hellodb数据库创建一个新表semitable

MariaDB [hellodb]> create table semitable (id int);

2)在从服务器上查看hellodb数据库是否有semitable

MariaDB [(none)]> use hellodb
MariaDB [hellodb]> show tables;(并没有)
+-------------------+
| Tables_in_hellodb |
+-------------------+
| classes   |
| coc    |
| courses   |
| scores   |
| students   |
| teachers   |
| toc    |
+-------------------+

3)在主服务器上创建mydb数据库,并为其创建一个tbl1表

MariaDB [hellodb]> create database mydb;

4)在从服务器上查看mydb数据库的是否有tbl1表

MariaDB [hellodb]> use mydb;
MariaDB [mydb]> show tables; (可以查看到)
+----------------+
| Tables_in_mydb |
+----------------+
| tbl1   |
+----------------+