How does MySQL achieve two-way mutual primary replication?

bidirectional Mutual Master from step:

12 machines Add a cluster machine access to the account given replication slave permissions

mysql> grant replication Slave on * * to ' rep ' @ ' 172.16.1.% ' identified by ' 1234566 ';

22 Machine parameter Configuration

Log_bin =/data/3307/mysql-bin

Log-slave-update

Relay-log =/data/3307/relay-bin Turn on the trunk log

server_id = 1 Another set to 2

Auto_increment-offset = 1 Start value another set to 2

Auto_increment-increment = 2 Step

3 from the boot server

/etc/init.dmysqld restart

42 servers change from one master to another

Change MASTER to

Master_host = ' HOST ', #另一台机器的地址

Master_port = 3306, #另一台机器的端口

Master_user = ' rep ', #另一台机器上第一步分配的用户名

Master_password = ' 123456 ', #另一台机器上第一步分配的密码

Master_log_file = ' mysql-bin.000001 ', #另一台机器上执行得到的文件名

Master_log_pos = 192; #另一台机器上得到的偏移量

If the master-slave replication is based on Gtid, don't look for Binglog and Pos points

Master_auto_position=1; #加上这个参数就可以

How does MySQL achieve two-way mutual primary replication?