First steps
mysql_secure_installation

Passwordpress login mysql

create ~/.my.cnf  with
[client]
password=plaintextpassword
user=root

Create Database

long variant ;
create database testdb;

create user ‘testuser’@’localhost’ identified by ‘password’;

grant all on testdb.* to ‘testuser’ identified by ‘password’;

short one :

create database testdb;

grant all on testdb.* to ‘testuser’ identified by ‘password’;

Reset the MySQL Root Password

systemctl stop mysqld
mysqld_safe –skip-grant-tables &
mysql -u root
use mysql; update user SET PASSWORD=PASSWORD(“password”) WHERE USER=’root’; flush privileges; exit

systemctl start mysqld

Replication

Add in /etc/my.cnf  in [mysqld]

—master—
server_id=1
log-basename=master
log-bin
binlog-format=row
binlog-do-db=$NAME-OF-DB-TO-REPLICATE

—slave—

server-id = 2
replicate-do-db=$NAME-OF-DB-TO-REPLICATE

mysql-master-sql

GRANT REPLICATION SLAVE ON *.* TO 'user'@'%' IDENTIFIED BY 'password';

start slave;

SHOW MASTER STATUS;

!!!!Position and  File !!!

mysql-slave-sql

stop slave;

CHANGE MASTER TO MASTER_HOST=’IP8′, MASTER_USER=’user’, MASTER_PASSWORD=’password’, MASTER_LOG_FILE=’mariadb-bin.000005‘, MASTER_LOG_POS=245 ,MASTER_CONNECT_RETRY=5 ;

start slave;

SHOW SLAVE STATUS\G;