How to realize master-slave synchronization in mysql5.7

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Preface

It was said before redis Master slave backup of ：

Mysql Master-slave replication means that data can be copied from one Mysql Database nodes are replicated to multiple Mysql Database nodes . Mysql The database adopts asynchronous replication mechanism by default . So for master Nodes and slave Node , Only weak consistency can be guaranteed . May exist master Nodes and slave Inconsistent node data .

redis Synchronization: full synchronization for the first time ,slave take master Copy all the data on .slave Discard previous data , Will receive RDB All files are imported , Then perform incremental synchronization .

and redis Different ,mysql The master-slave synchronization can only be based on the synchronization of data operations after the setup , Unable to synchronize previous data , Therefore, manual synchronization is required

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One 、 principle ？

1.master Node passing foke A thread records data changes to binlog In file
2.slave Node passing io Threads go every time master Node acquisition binlog Log data , Save to relay log In the relay log
3.slave The node detects that the relay log is updated ,sql The thread will synchronize the updated content to slave In nodes

tip： Remember the previous log listener ？？

Two 、 step

1.master build

139.9.186.192 Server as master

1. Pull the mirror , Today pull 5.7 edition 
 docker pull mysql:5.7
2. function mysql-master 
 docker run -d -p 3306:3306 --name mysql-master -e MYSQL_ROOT_PASSWORD=123456 mysql:5.7
3. Updates and Downloads vim plug-in unit 
 1.docker exec -it mysql-master /bin/bash
 2.apt-get update
 3.apt-get install vim
4. open my.cnf file 
 vim /etc/mysql/my.cnf
5. modify my.cnf file , Add the following file 
 [mysqld]  // Required 
 server_id=1 // If you deploy a cluster under the same LAN , So many mysql Of server_id Cannot be the same 
 log-bin=mysql-bin // Log name 
 expire_logs_days=7 // Automatic cleaning log Time 
6. restart mysql-master
7. See if it works 
 1. Get into docker exec -it mysql-master /bin/bash
 2. Use mysql> mysql -u root -p 
 3.mysql> show variables like '%log_bin%'; //log_bin The log is on
8. Create users connected from the Library 
 mysql> grant replication slave on *.* to 'slave'@'%' identified by '123456';
9. View the status of the primary database 
 mysql> show master status // Record file Name and position Connect from the library later 

2.slave build

1.15.233.184 by slave

1. Pull the mirror , PULL 5.7 edition 
 docker pull mysql:5.7
2. function mysql-master 
 docker run -d -p 3306:3306 --name mysql-slave -e MYSQL_ROOT_PASSWORD=123456 mysql:5.7
3. Updates and Downloads vim plug-in unit 
 1.docker exec -it mysql-slave /bin/bash
 2.apt-get update
 3.apt-get install vim
4. open my.cnf file 
 vim /etc/mysql/my.cnf
5. modify my.cnf file 
	[mysqld]
	server_id=2
	read_only=1  // take slave Set the slave library to read only ,0 In read-write status 
6. restart salve, Once again into the 
7. Connect to mysql, Connect to master
 mysql> change master to
 -> master_host='139.9.186.192',
 -> master_user='slave',
 -> master_password='123456',
 -> master_log_file='mysql-bin.000001',  // Fill in what you are asked to record file
 -> master_log_pos=406; // Fill in what you are asked to record position
 mysql> start slave;

test ：

from master Add one test database , that slave Will receive . If in slave add to , that master Will not receive

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