数据库的主从复制
转载
mariadb的主从复制、主主复制、半同步复制配置详解
转载自:mariadb的主从复制、主主复制、半同步复制配置详解
主1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
在[mysqld]
段的最后添加以下内容
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
在[mysqld]
段的最后添加以下内容
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;
4、半同步复制的优化
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
在[mysqld]
段的最后添加以下内容
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 |
+----------------+