Master节点必须开启二进制日志功能;

Slave节点必须开启中继日志功能;

Slave节点需关闭二进制日志功能(默认不配置即可);

Master和Slave节点需要配置不同的server-id;

Slave节点需连接到Master节点.

cat /etc/yum.repos.d/mariadb.repo

[mariadb]

name=MariaDB

baseurl=http://mirrors.ustc.edu.cn/mariadb/yum/10.2/centos7-amd64/

gpgkey=http://mirrors.ustc.edu.cn/mariadb/yum/RPM-GPG-KEY-MariaDB

gpgcheck=1

yum -y install MariaDB-server MariaDB-client

# 已经包含半同步复制插件

find /usr/ -name semisync*

/usr/lib64/mysql/plugin/semisync_master.so

/usr/lib64/mysql/plugin/semisync_slave.so

systemctl start mariadb

# 除了将密码改为mariadb123456,其余步骤都按Y

/usr/bin/mysql_secure_installation

# 在Master和Slave首次启动时,安装插件,开启半同步复制

# 在10.0.0.21上安装master插件

install plugin rpl_semi_sync_master soname 'semisync_master.so';

set global rpl_semi_sync_master_enabled =1;

# 在10.0.0.22上安装slave插件

install plugin rpl_semi_sync_slave soname 'semisync_slave.so';

set global rpl_semi_sync_slave_enabled = 1;

# 在10.0.0.21上授权用户,repluser用于复制数据

grant replication slave,replication client on *.* to 'repluser'@'10.0.0.%' identified by 'repluser123456';

flush privileges;

# 主节点配置文件

cat /etc/my.cnf.d/server.cnf

[mysqld]

skip_name_resolve = ON

innodb_file_per_table = ON

server-id = 21

log-bin = master-bin

log-bin-index = master-bin.index

rpl_semi_sync_master_enabled = 1

rpl_semi_sync_master_timeout = 1000

# 从节点配置文件

cat /etc/my.cnf.d/server.cnf

[mysqld]

skip_name_resolve = ON

innodb_file_per_table = ON

server_id = 22

relay_log = slave_relay_bin

relay_log_index = slave_relay_bin.index

rpl_semi_sync_slave_enabled = 1

systemctl restart mariadb.service

# 查看10.0.0.21上的Position位置

show master status\G

File: master-bin.000001

Position: 329

# 在10.0.0.22上show status like '%semi%';发现是OFF,执行change master,开启同步

change master to master_host='10.0.0.21',master_user='repluser',

master_password='repluser123456',master_log_file='master-bin.000001',master_log_pos=329;

start slave;

show variables like '%semi%';

rpl_semi_sync_master_enabled     ON

rpl_semi_sync_master_timeout     1000

rpl_semi_sync_master_trace_level   32

rpl_semi_sync_master_wait_no_slave  ON

rpl_semi_sync_master_wait_point    AFTER_COMMIT

show status like '%semi%';

Rpl_semi_sync_master_clients   1

Rpl_semi_sync_master_no_tx    0

Rpl_semi_sync_master_status   ON

Rpl_semi_sync_master_yes_tx   0

a.首先同步创建数据库testdb;

b.slave执行stop slave;关闭主从复制;

c.master在testdb数据库中创建表create table student(id int,name varchar(20));

没接收到反馈信号,等待1秒后继续执行;

d.master在数据库中再创建subject,不需要等待反馈,直接执行,因为反馈超时,master已切换到异步复制模式;

e.slave执行start slave,数据开始同步,反馈给master,master切换为半同步复制.