Mysql (MariaDB) Асесс отказано после перезагрузки

Question

Arch Linux, Mariadb 10.1.21-1. 
My commands: 
    yaourt -S mariadb 
    mysql_install_db --user=mysql --basedir=/usr --datadir=/var/lib/mysql 
    sudo systemctl start mariadb 
    mysql_secure_installation 
    yes 
    yes 
    set root pass 
    password 
    yes 
    yes 
    mysql -u root -ppassword 
    CREATE DATABASE db; 
    CREATE USER 'username'@'localhost' IDENTIFIED BY 'password'; 
    GRANT ALL PRIVILEGES ON db.* TO 'username'@'localhost'; 
    quit; 
    mysql -u username -ppassword 
    ALL OK! 
    quit; 
    sudo systemctl stop mariadb; 
    sudo shutdown -r now; 
    ... 
    sudo systemctl start mariadb; 
    mysql -u coolone -ppassword; 
    ERROR 1045 (28000): Access denied for user 'coolone'@'localhost' (using password: YES) 

Answer 1

mysql -u root -ppassword 
    CREATE DATABASE db; 
    CREATE USER 'username'@'localhost' IDENTIFIED BY 'password'; 
    GRANT ALL PRIVILEGES ON db.* TO 'username'@'localhost'; 
    FLUSH PRIVILEGES; 
quit;