准备工作

服务器1：IP：192.168.4.58 操作系统CentOS6.8 数据库：MySQL5.6
服务器1：IP：192.168.4.88 操作系统CentOS6.8 数据库：MySQL5.6

主从配置的前提条件

1、MySQL版本一致
2、MySQL中的数据一致
3、操作前停止一切更新操作（写入、更新、删除等）

配置步骤

配置master
1、修改配置文件
vim /etc/my.cnf
log-bin=mysql-bin 启用二进制日志，mysql-bin为自己取名字
server-id=58 服务器ID，唯一性，一般是IP地址最后一段
binlog_format=mixed 日志存储格式
2、创建备份专用账户

mysql> GRANT REPLICATION SLAVE ON *.* TO 'backup'@'%' IDENTIFIED BY '123456';
mysql> FLUSH PRIVILEGES;

3、查看master主机状态
mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000001 | 120 | | | |
+------------------+----------+--------------+------------------+-------------------+
注：File 和Position 值待会儿要用到
4、关闭防火墙
[root@master ~]# service iptables stop
配置 slave
1、修改配置文件
vim /etc/my.cnf
log-bin=mysql-bin [可选] 启用二进制日志
relay-log=relay-log 启用中继日志
server-id=88 配置服务器ID
2、配置主从复制
mysql> change master to
master_host='192.168.4.58',master_user='backup',master_password='123456',master_log_file='mysql-bin.000001', master_log_pos=120;

注：
master_host=主服务器IP
master_user=在主服务器上创建的备份用户名
master_password=备份用户密码
master_log_file=查询master(主服务器)的状态得到的File列的值
master_log_pos=Position列的值
start slave：启动从服务器复制功能
3、启动从服务器
mysql> start slave;
4、检查从服务器复制功能状态
mysql> show slave status\G;
1. row
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.4.58
Master_User: backup
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000002
Read_Master_Log_Pos: 120
Relay_Log_File: relay-log.000004
Relay_Log_Pos: 283
Relay_Master_Log_File: mysql-bin.000002
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: 120
Relay_Log_Space: 613
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: 58
Master_UUID: ebb71aca-381c-11e8-8b6d-000c29138f00
Master_Info_File: /data/mysql/master.info
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for the slave I/O thread to update it
Master_Retry_Count: 86400
Master_Bind:
Last_IO_Error_Timestamp:
Last_SQL_Error_Timestamp:
Master_SSL_Crl:
Master_SSL_Crlpath:
Retrieved_Gtid_Set:
Executed_Gtid_Set:
Auto_Position: 0
5、设置从服务器为只读
mysql> SHOW GLOBAL VARIABLES LIKE 'READ%';
+----------------------+--------+
| Variable_name | Value |
+----------------------+--------+
| read_buffer_size | 131072 |
| read_only | OFF |
| read_rnd_buffer_size | 262144 |
+----------------------+--------+
在slave的mysql配置文件中修改： read-only=on（在从服务器上设定，但对具有SUPER权限的用户不生效）

主要查看以下两项：
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Slave_IO及Slave_SQL进程必须正常运行，即YES状态，否则都是错误的状态(如：其中一个NO均属错误)。
以上操作过程，主从服务器配置完成。

主从服务器测试

在主服务器上执行以下操作：
mysql -uroot -ppassword
create database db_test_slave;
use db_test_slave;
create table tb_test(id int(3), name varchar(50));
insert into tb_test values(1,'hello slave');
show databases;
mysql> select * from db_test_slave.tb_test;

在从服务器上执行以下操作：
[root@node2 ~]# mysql -uroot -p123456 -e "show databases;use db_test_slave; select * from tb_test;"
| Database |
+--------------------+
| information_schema |
| db_test_slave |
| mysql |
| performance_schema |
| test |
+--------------------+
+------+-------------+
| id | name |
+------+-------------+
| 1 | hello_slave |
+------+-------------+
看到在主服务器上创建的数据库、数据表、插入的数据记录。

MySQL的半同步复制

1、分别在主从节点上安装相关的插件
master：
安装插件：mysql> INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_master.so';
启动模块：mysql> SET GLOBAL rpl_semi_sync_master_enabled = 1;
（ rpl_semi_sync_master模块名称，semisync_master.so模块文件）
（取消加载插件mysql> UNINSTALL PLUGIN rpl_semi_sync_master;）
2、查看安装的模块
mysql> SHOW GLOBAL VARIABLES LIKE '%rpl%';
+------------------------------------+----------+
| Variable_name | Value |
+------------------------------------+----------+
| rpl_semi_sync_master_enabled | ON |
| rpl_semi_sync_master_timeout | 10000 |
| rpl_semi_sync_master_trace_level | 32 |
| rpl_semi_sync_master_wait_no_slave | ON |
| rpl_stop_slave_timeout | 31536000 |
+------------------------------------+----------+
slave：
安装插件：msyql> INSTALL PLUGIN rpl_semi_sync_slave SONAME 'semisync_slave.so';
启动模块：mysql> SET GLOBAL rpl_semi_sync_slave_enabled = 1;
重启进程使其模块生效：mysql> STOP SLAVE IO_THREAD; START SLAVE IO_THREAD;

mysql> STOP SLAVE IO_THREAD; START SLAVE IO_THREAD; （将从线程关掉在启动才可以）
mysql> show global variables like "rpl%";
+---------------------------------+----------+
| Variable_name | Value |
+---------------------------------+----------+
| rpl_semi_sync_slave_enabled | ON |
| rpl_semi_sync_slave_trace_level | 32 |
| rpl_stop_slave_timeout | 31536000 |
+---------------------------------+----------+