How to Install MySQL 5.7 on CentOS 7 and Reset the Root Password

Background

MySQL Server 5.7 was installed on a CentOS 7 system using the official MySQL community RPM package ( mysql57-community-release-el7-7.noarch.rpm). After installation, attempting to log in as root failed with

ERROR 1045 (28000): Access denied for user 'root'@'localhost'

.

Why the login fails

Starting with MySQL 5.7 the server creates the root account with a random temporary password. The traditional mysqld_safe script is no longer provided, and the user table column password has been renamed to authentication_string. Consequently, the usual password‑reset procedures that modify user.password do not work.

Installation (RPM method)

su root
sudo wget http://repo.mysql.com/mysql57-community-release-el7-7.noarch.rpm
sudo rpm -ivh mysql57-community-release-el7-7.noarch.rpm
sudo yum install mysql-server

Key changes in MySQL 5.7

mysqld_safe has been removed; the RPM package does not install it.

The user table column password is now called authentication_string.

Resetting the root password

Use systemd to start MySQL with grant tables disabled, change the password, then restart the service.

sudo systemctl stop mysqld.service

sudo systemctl set-environment MYSQLD_OPTS="--user=mysql --skip-grant-tables --skip-networking"

sudo systemctl start mysqld.service

Connect without authentication: mysql -u root mysql At the MySQL prompt, update the password and flush privileges:

UPDATE mysql.user SET authentication_string=PASSWORD('abcdef') WHERE user='root' AND host='localhost';
FLUSH PRIVILEGES;
QUIT;

sudo systemctl unset-environment MYSQLD_OPTS

sudo systemctl restart mysqld.service

After these steps the root account can log in using the new password (e.g., abcdef).