MySQL 5.6 Reference Manual Including MySQL NDB Cluster 7.3-7.4 Reference Guide
If you have never assigned a root
password
for MySQL, the server does not require a password at all for
connecting as root
. However, this is
insecure. For instructions on assigning passwords, see
Section 2.10.4, “Securing the Initial MySQL Accounts”.
If you know the root
password and want to
change it, see Section 13.7.1.7, “SET PASSWORD Statement”.
If you assigned a root
password previously
but have forgotten it, you can assign a new password. The
following sections provide instructions for Windows and Unix
and Unix-like systems, as well as generic instructions that
apply to any system.
On Windows, use the following procedure to reset the
password for the MySQL 'root'@'localhost'
account. To change the password for a
root
account with a different host name
part, modify the instructions to use that host name.
Log on to your system as Administrator.
Stop the MySQL server if it is running. For a server that is running as a Windows service, go to the Services manager: From the
menu, select , then , then . Find the MySQL service in the list and stop it.If your server is not running as a service, you may need to use the Task Manager to force it to stop.
Create a text file containing the following statement on a single line. Replace the password with the password that you want to use.
SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MyNewPass');
Save the file. This example assumes that you name the
file C:\mysql-init.txt
.
Open a console window to get to the command prompt: From the cmd as the command to be run.
menu, select , then enter
Start the MySQL server with the
init_file
system
variable set to name the file (notice that the backslash
in the option value is doubled):
C:\>cd "C:\Program Files\MySQL\MySQL Server 5.6\bin"
C:\>mysqld --init-file=C:\\mysql-init.txt
If you installed MySQL to a different location, adjust the cd command accordingly.
The server executes the contents of the file named by
the init_file
system
variable at startup, changing the
'root'@'localhost'
account password.
To have server output to appear in the console window
rather than in a log file, add the
--console
option to the
mysqld command.
If you installed MySQL using the MySQL Installation
Wizard, you may need to specify a
--defaults-file
option.
For example:
C:\>mysqld
--defaults-file="C:\\ProgramData\\MySQL\\MySQL Server 5.6\\my.ini"
--init-file=C:\\mysql-init.txt
The appropriate
--defaults-file
setting
can be found using the Services Manager: From the
menu, select
, then
, then
. Find the MySQL
service in the list, right-click it, and choose the
Properties
option. The Path
to executable
field contains the
--defaults-file
setting.
After the server has started successfully, delete
C:\mysql-init.txt
.
You should now be able to connect to the MySQL server as
root
using the new password. Stop the
MySQL server and restart it normally. If you run the server
as a service, start it from the Windows Services window. If
you start the server manually, use whatever command you
normally use.
On Unix, use the following procedure to reset the password
for the MySQL 'root'@'localhost'
account.
To change the password for a root
account
with a different host name part, modify the instructions to
use that host name.
The instructions assume that you start the MySQL server from
the Unix login account that you normally use for running it.
For example, if you run the server using the
mysql
login account, you should log in as
mysql
before using the instructions.
Alternatively, you can log in as root
,
but in this case you must start
mysqld with the
--user=mysql
option. If you
start the server as root
without using
--user=mysql
, the server may
create root
-owned files in the data
directory, such as log files, and these may cause
permission-related problems for future server startups. If
that happens, you must either change the ownership of the
files to mysql
or remove them.
Log on to your system as the Unix user that the MySQL
server runs as (for example, mysql
).
Stop the MySQL server if it is running. Locate the
.pid
file that contains the
server's process ID. The exact location and name of this
file depend on your distribution, host name, and
configuration. Common locations are
/var/lib/mysql/
,
/var/run/mysqld/
, and
/usr/local/mysql/data/
. Generally,
the file name has an extension of
.pid
and begins with either
mysqld
or your system's host name.
Stop the MySQL server by sending a normal
kill
(not kill -9
)
to the mysqld process. Use the actual
path name of the .pid
file in the
following command:
shell> kill `cat /mysql-data-directory/host_name.pid`
Use backticks (not forward quotation marks) with the
cat
command. These cause the output
of cat
to be substituted into the
kill
command.
Create a text file containing the following statement on a single line. Replace the password with the password that you want to use.
SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MyNewPass');
Save the file. This example assumes that you name the
file /home/me/mysql-init
. The file
contains the password, so do not save it where it can be
read by other users. If you are not logged in as
mysql
(the user the server runs as),
make sure that the file has permissions that permit
mysql
to read it.
Start the MySQL server with the
init_file
system
variable set to name the file:
shell> mysqld --init-file=/home/me/mysql-init &
The server executes the contents of the file named by
the init_file
system
variable at startup, changing the
'root'@'localhost'
account password.
Other options may be necessary as well, depending on how
you normally start your server. For example,
--defaults-file
may be
needed before the
init_file
argument.
After the server has started successfully, delete
/home/me/mysql-init
.
You should now be able to connect to the MySQL server as
root
using the new password. Stop the
server and restart it normally.
The preceding sections provide password-resetting instructions specifically for Windows and Unix and Unix-like systems. Alternatively, on any platform, you can reset the password using the mysql client (but this approach is less secure):
Stop the MySQL server if necessary, then restart it with
the --skip-grant-tables
option. This enables anyone to connect without a
password and with all privileges, and disables
account-management statements such as
SET PASSWORD
. Because
this is insecure, you might want to use
--skip-grant-tables
in
conjunction with enabling the
skip_networking
system
variable to prevent remote clients from connecting.
Connect to the MySQL server using the
mysql client; no password is
necessary because the server was started with
--skip-grant-tables
:
shell> mysql
In the mysql
client, tell the server
to reload the grant tables so that account-management
statements work:
mysql> FLUSH PRIVILEGES;
Then change the 'root'@'localhost'
account password. Replace the password with the password
that you want to use. To change the password for a
root
account with a different host
name part, modify the instructions to use that host
name.
mysql> SET PASSWORD FOR 'root'@'localhost' = PASSWORD('MyNewPass');
You should now be able to connect to the MySQL server as
root
using the new password. Stop the
server and restart it normally (without the
--skip-grant-tables
option
and without enabling the
skip_networking
system
variable).