A brief discussion on three methods of asynchronous replication in MySQL 8.0

[root@slave2 ~]# cat /etc/hosts
192.168.2.138 master
192.168.2.192 slave1
192.168.2.130 slave2
mysql> select version();
+-----------+
| version() |
+-----------+
| 8.0.16 |
+-----------+
1 row in set (0.00 sec)

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000004 | 155 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

mysql> create user 'repl'@'%' identified with mysql_native_password by 'wwwwww';
Query OK, 0 rows affected (0.03 sec)
mysql> grant replication client,replication slave on *.* to 'repl'@'%';
Query OK, 0 rows affected (0.04 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

mysql> stop slave;
mysql> change master to master_host='192.168.2.138', master_port=3306, master_user='repl', master_password='wwwwww', master_log_file='mysql-bin.000004', master_log_pos=155;
Query OK, 0 rows affected, 2 warnings (0.00 sec)
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)
mysql> show slave status\G

sql> select * from mysql.user where user='repl'\G

CREATE DATABASE test;
Query OK, 1 row affected (0.04 sec)
mysql> USE test;
Database changed
mysql> CREATE TABLE t(id int(10));
Query OK, 0 rows affected (0.09 sec)
mysql> INSERT INTO t VALUES (111);
Query OK, 1 row affected (0.05 sec)
mysql> INSERT INTO t VALUES (222);
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO t VALUES (333);
Query OK, 1 row affected (0.00 sec)

mysql> create user 'repl'@'%' identified with mysql_native_password by 'wwwwww';
Query OK, 0 rows affected (0.03 sec)
mysql> grant replication client,replication slave on *.* to 'repl'@'%';
Query OK, 0 rows affected (0.04 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)

[root@master ~]# ln -s /usr/local/mysql/bin/mysqladmin /usr/bin/mysqladmin
[root@master ~]# mysqladmin -hlocalhost -uroot -pwwwwww shutdown

[root@master data]# cd /data
[root@master data]# scp -r mysql/ slave1:/data/
[root@master data]# scp -r mysql/ slave2:/data/

[root@slave1 mysql]# cd /data/mysql
[root@slave1 mysql]# rm -rf auto.cnf
[root@slave2 mysql]# cd /data/mysql
[root@slave2 mysql]# rm -rf auto.cnf
 

[root@master data]# service mysqld start
Starting MySQL.. SUCCESS!

mysql> show master status;
+------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+-------------------+
| mysql-bin.000005 | 155 | | | |
+------------------+----------+--------------+------------------+-------------------+
1 row in set (0.00 sec)

mysql> stop slave;
Query OK, 0 rows affected (0.01 sec)
mysql> change master to master_host='192.168.2.138', master_port=3306, master_user='repl', master_password='wwwwww', master_log_file='mysql-bin.000005', master_log_pos=155;
Query OK, 0 rows affected, 2 warnings (0.02 sec)
mysql> start slave;
Query OK, 0 rows affected (0.03 sec)
mysql> show slave status\G

mysql> use test;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> show tables;
+----------------+
| Tables_in_test |
+----------------+
| t |
+----------------+
1 row in set (0.00 sec)
mysql> select * from t;
+------+
|id|
+------+
| 111 |
| 222 |
| 333 |
+------+
3 rows in set (0.00 sec)

mysql> CREATE DATABASE test;
Query OK, 1 row affected (0.04 sec)
mysql> use test;
Database changed
mysql> CREATE TABLE t(id int(10));
Query OK, 0 rows affected (0.10 sec)
mysql> INSERT INTO t VALUES(111);
Query OK, 1 row affected (0.09 sec)
mysql> INSERT INTO t VALUES(222);
Query OK, 1 row affected (0.00 sec)
mysql> INSERT INTO t VALUES(333);
Query OK, 1 row affected (0.05 sec)
mysql> INSERT INTO t VALUES(444);
Query OK, 1 row affected (0.00 sec)

mysql> create user 'repl'@'%' identified with mysql_native_password by 'wwwwww';
Query OK, 0 rows affected (0.01 sec)
mysql> grant replication client,replication slave on *.* to 'repl'@'%';
Query OK, 0 rows affected (0.01 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)
 

mysql> change master to master_host='192.168.2.138', master_port=3306, master_user='repl', master_password='wwwwww';
Query OK, 0 rows affected, 2 warnings (0.04 sec)

[root@slave2 ~]# mysqldump --single-transaction --all-databases --master-data=1 --host=192.168.2.138 --user=root --password=wwwwww --apply-slave-statements | mysql -uroot -pwwwwww -hlocalhost
mysql: [Warning] Using a password on the command line interface can be insecure.
mysqldump: [Warning] Using a password on the command line interface can be insecure.

mysql> show slave status\G

use test;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select * from t;
+------+
|id|
+------+
| 111 |
| 222 |
| 333 |
| 444 |
| 555 |
+------+
5 rows in set (0.00 sec)

mysql> create user 'repl'@'%' identified with mysql_native_password by 'wwwwww';
Query OK, 0 rows affected (0.01 sec)
mysql> grant replication client,replication slave on *.* to 'repl'@'%';
Query OK, 0 rows affected (0.01 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

[root@master ~]# yum -y install libev
[root@master home]# yum localinstall percona-xtrabackup-80-8.0.6-1.el7.x86_64.rpm -y

[root@master home]# ssh-keygen 
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa): 
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:GBLbrw17UVck8RyCa/fbYyLkSNZIRc5p+jPQmpkD+bI root@master
The key's randomart image is:
+---[RSA 2048]----+
| . .o+o+ |
| + +..* . |
| ooo*.o |
| . +.o*.. |
|ooS+oo . |
| =o=Bo . |
| o.=B++ o |
| .o..oo..o.|
| E . o .|
+----[SHA256]-----+
[root@master home]# ssh-copy-id 192.168.2.138
[root@master home]# ssh-copy-id 192.168.2.192
[root@master home]# ssh-copy-id 192.168.2.130

[root@slave1 home]# service mysql stop
[root@slave2 home]# service mysql stop
[root@slave1 home]# rm -rf /data/mysql/*
[root@slave2 home]# rm -rf /data/mysql/*

[root@master tmp]# xtrabackup -uroot -pwwwwww --socket=/data/mysql/mysql.sock --no-lock --backup --compress --stream=xbstream --parallel=4 --target-dir=./ | ssh root@192.168.2.192 "xbstream -x -C /data/mysql/ --decompress"

mysql> grant BACKUP_ADMIN on *.* to 'root'@'%';
Query OK, 0 rows affected (0.01 sec)

[root@slave1 /]# xtrabackup --prepare --target-dir=/data/mysql
[root@slave2 /]# xtrabackup --prepare --target-dir=/data/mysql

[root@slave1 mysql]# cat xtrabackup_binlog_info 
mysql-bin.000008 155
[root@slave2 mysql]# cat xtrabackup_binlog_info 
mysql-bin.000009 155

[root@slave1 data]# service mysqld start
Starting MySQL... SUCCESS! 
[root@slave2 data]# service mysqld start
Starting MySQL... SUCCESS!

mysql> change master to master_host='192.168.2.138', master_port=3306, master_user='repl', master_password='wwwwww', master_log_file='mysql-bin.000008', master_log_pos=155;
Query OK, 0 rows affected, 2 warnings (0.04 sec)
mysql> start slave;
Query OK, 0 rows affected (0.00 sec)
mysql> show slave status\G

mysql> use test;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Database changed
mysql> select * from t;
+------+
|id|
+------+
| 111 |
| 222 |
| 333 |
| 444 |
| 555 |
+------+
5 rows in set (0.00 sec)