1. 实验环境

System

IP

Host

CentOS 7.4.1708

192.168.100.101

master

CentOS 7.4.1708

192.168.100.102

slave

2. 安装MySQL8

3. 配置主从复制

要想将主节点配置为使用基于二进制日志的复制，必须确保启用了二进制日志记录，并建立唯一的服务器ID

[root@master ~]# cat /etc/my.cnf

[mysqld]

datadir=/var/lib/mysql # 这是数据存放的路径

socket=/var/lib/mysql/mysql.sock # 这是监听的套接字

log-error=/var/log/mysqld.log # 日志输出的路径

pid-file=/var/run/mysqld/mysqld.pid # pid存放的路径

log-bin=on # 开启二进制日志

server-id=1 # 服务器id为1

[root@slave ~]# cat /etc/my.cnf

[mysqld]

datadir=/var/lib/mysql

socket=/var/lib/mysql/mysql.sock

log-error=/var/log/mysqld.log

pid-file=/var/run/mysqld/mysqld.pid

server-id=2

主节点server-id为0：拒绝来自从节点的任何连接

从节点server-id为0：拒绝连接到主节点

4. 配置复制用户

创建一个只能复制的用户。

mysql> CREATE USER 'repl'@'192.168.100.101' IDENTIFIED BY 'MyNewPass4!';

Query OK, 0 rows affected (0.02 sec)

mysql> GRANT REPLICATION SLAVE ON *.* TO 'repl'@'192.168.100.101';

Query OK, 0 rows affected (0.06 sec)

mysql> FLUSH PRIVILEGES;

Query OK, 0 rows affected (0.01 sec)

5. 数据的同步

在配置之前，要注意的是，主节点现在的数据与从节点是不同步的，这可能导致复制失败，所以你可能需要将主节点的数据手动导入到从节点。在此你必须保证数据不被写入，所以你需要阻止写入。

# 这条命令会阻止对所有表的写入操作，但当前客户端断开，则会释放锁定

mysql> FLUSH TABLES WITH READ LOCK;

# 这条命令是确定当前二进制日志文件的名称和位置。

mysql> show master status;

+---------------+----------+--------------+------------------+-------------------+

| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |

+---------------+----------+--------------+------------------+-------------------+

| binlog.000002 | 866 | | | |

+---------------+----------+--------------+------------------+-------------------+

1 row in set (0.00 sec)

6. 配置从节点

mysql> CHANGE MASTER TO

MASTER_HOST='192.168.100.101', # 主节点地址

MASTER_USER='repl', # 主节点用户

MASTER_PASSWORD='MyNewPass4!', # 主节点密码

MASTER_LOG_FILE='binlog.000002', # 二进制日志文件

MASTER_LOG_POS=866; # 二进制日志位置

Query OK, 0 rows affected, 2 warnings (0.05 sec)

mysql> START SLAVE;

Query OK, 0 rows affected (0.04 sec)

mysql> SHOW SLAVE STATUS\G

*************************** 1. row ***************************

Slave_IO_State: Waiting for master to send event

Master_Host: 192.168.100.101

Master_User: repl

Master_Port: 3306

Connect_Retry: 60

Master_Log_File: binlog.000002

Read_Master_Log_Pos: 866

Relay_Log_File: slave-relay-bin.000003

Relay_Log_Pos: 319

Relay_Master_Log_File: binlog.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: 866

Relay_Log_Space: 691

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

Master_UUID: aa8d6cc4-5f26-11e9-b7d7-000c29999aa1

Master_Info_File: mysql.slave_master_info

SQL_Delay: 0

SQL_Remaining_Delay: NULL

Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates

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

Replicate_Rewrite_DB:

Channel_Name:

Master_TLS_Version:

Master_public_key_path:

Get_master_public_key: 0

1 row in set (0.00 sec)

7. 测试主从复制

# 主节点

mysql> CREATE DATABASE REPL;

Query OK, 1 row affected (0.04 sec)

# 从节点

mysql> SHOW DATABASES;

+--------------------+

| Database |

+--------------------+

| REPL |

| information_schema |

| mysql |

| performance_schema |

| sys |

+--------------------+

5 rows in set (0.01 sec)