How to change the MySQL root account password on CentOS7?

Question

I have installed mySQL on a Centos7 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 look

Answer 1

I used the advice of Kevin Jones above with the following --skip-networking change for slightly better security:

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

[user@machine ~]$ mysql -u root

Then when attempting to reset the password I received an error, but googling elsewhere suggested I could simply forge ahead. The following worked:

mysql> select user(), current_user();
+--------+-----------------------------------+
| user() | current_user()                    |
+--------+-----------------------------------+
| root@  | skip-grants user@skip-grants host |
+--------+-----------------------------------+
1 row in set (0.00 sec)

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'sup3rPw#'
ERROR 1290 (HY000): The MySQL server is running with the --skip-grant-tables option so it cannot execute this statement
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.02 sec)

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'sup3rPw#'
Query OK, 0 rows affected (0.08 sec)

mysql> exit
Bye
[user@machine ~]$ systemctl stop mysqld
[user@machine ~]$ sudo systemctl unset-environment MYSQLD_OPTS
[user@machine ~]$ systemctl start mysqld

At that point I was able to log in.