Question

I have long since forgotten the password for the root user on one of my boxes. Is there a way I can change it without having to log in to the instance, or will I have to reinstall?

Answer 1

Step 1

Stop database:

shell> /etc/init.d/mysql stop 

Step 2

Restart database

• without password autentification
• without connection to the network

Access to database is only possible through it’s sock file ‘/var/lib/mysql/mysql.sock’.

shell> mysqld --user=mysql --pid-file=/var/lib/mysql/mysqld.pid \        --socket=/var/lib/mysql/mysql.sock --datadir=/var/lib/mysql \        --skip-grant-tables --skip-networking  & 

Step 3

Connect to the database and change password:

shell> mysql --database mysql --socket=/var/lib/mysql/mysql.sock 

If you want to, show all users:

mysql> select User, password from user; 

Set new password:

mysql> update user set password=password('NEW PASS') WHERE User='USERNAME'; 

Leave database connection:

mysql> exit 

Step 4

Restart database server ‘normally’.

shell> kill `cat /var/lib/mysql/mysqld.pid` shell> /etc/init.d/mysql start