How to change the MySQL root account password on CentOS 7?

I have installed mySQL on a CentOS 7 VM but I have problems logging in with root.

I tried logging in without password or tried any default ones (like mysql, admin etc) I looked in the my.cnf file and there's no password. I tried changing the password by stopping the service and restarting it with:

mysqld_safe --skip-grant-tables &

But I get this message:

mysqld_safe:command not found

I have no idea what else to do.

Solution

What version of mySQL are you using? I''m using 5.7.10 and had the same problem with logging on as root

There is 2 issues - why can't I log in as root to start with, and why can I not use 'mysqld_safe` to start mySQL to reset the root password.

I have no answer to setting up the root password during installation, but here's what you do to reset the root password

Edit: the initial root password on install can be found by running

grep 'temporary password' /var/log/mysqld.log

http://dev.mysql.com/doc/refman/5.7/en/linux-installation-yum-repo.html

systemd is now used to look after mySQL instead of mysqld_safe (which is why you get the -bash: mysqld_safe: command not found error - it's not installed)
The user table structure has changed.

So to reset the root password, you still start mySQL with --skip-grant-tables options and update the user table, but how you do it has changed.

Stop MySQL:
```
sudo systemctl stop mysqld
```

Set the MySQL environment option:

sudo systemctl set-environment MYSQLD_OPTS="--skip-grant-tables"

Start MySQL using the options you just set:
```
sudo systemctl start mysqld
```
Login as root
```
mysql -u root
```

Update the root user password with these mysql commands:

mysql> UPDATE mysql.user SET authentication_string = PASSWORD('MyNewPassword')
    -> WHERE User = 'root' AND Host = 'localhost';
mysql> FLUSH PRIVILEGES;
mysql> quit

Edit: As mentioned my shokulei in the comments, for 5.7.6 and later, you should use:

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'MyNewPass';

Or you'll get a warning

Stop MySQL
```
sudo systemctl stop mysqld
```
Unset the MySQL environment option so it starts normally next time:
```
sudo systemctl unset-environment MYSQLD_OPTS
```
Start MySQL normally:
```
sudo systemctl start mysqld
```
Try to login using your new password:
```
mysql -u root -p
```

Reference

As it says at http://dev.mysql.com/doc/refman/5.7/en/mysqld-safe.html,

Note

As of MySQL 5.7.6, for MySQL installation using an RPM distribution, server startup and shutdown is managed by systemd on several Linux platforms. On these platforms, mysqld_safe is no longer installed because it is unnecessary. For more information, see Section 2.5.10, “Managing MySQL Server with systemd”.

Which takes you to http://dev.mysql.com/doc/refman/5.7/en/server-management-using-systemd.html where it mentions the systemctl set-environment MYSQLD_OPTS= towards the bottom of the page.

The password reset commands are at the bottom of http://dev.mysql.com/doc/refman/5.7/en/resetting-permissions.html