Oracle 5.0 Reference Manual page 611

• Make sure that the server has not been configured to ignore network connections or (if you are
attempting to connect remotely) that it has not been configured to listen only locally on its network
interfaces. If the server was started with
connections at all. If the server was started with
for TCP/IP connections only locally on the loopback interface and will not accept remote connections.
• Check to make sure that there is no firewall blocking access to MySQL. Your firewall may be
configured on the basis of the application being executed, or the port number used by MySQL for
communication (3306 by default). Under Linux or Unix, check your IP tables (or similar) configuration
to ensure that the port has not been blocked. Under Windows, applications such as ZoneAlarm or
the Windows XP personal firewall may need to be configured not to block the MySQL port.
• The grant tables must be properly set up so that the server can use them for access control. For
some distribution types (such as binary distributions on Windows, or RPM distributions on Linux),
the installation process initializes the
that do not do this, you must initialize the grant tables manually by running the
script. For details, see
To determine whether you need to initialize the grant tables, look for a
data directory. (The data directory normally is named
installation directory.) Make sure that you have a file named
directory. If not, execute the
server, test the initial privileges by executing this command:
shell> mysql -u root test
The server should let you connect without error.
• After a fresh installation, you should connect to the server and set up your users and their access
permissions:
shell> mysql -u root mysql
The server should let you connect because the MySQL
also a security risk, so setting the password for the
you're setting up your other MySQL accounts. For instructions on setting the initial passwords, see
Section 2.18.2, "Securing the Initial MySQL
• If you have updated an existing MySQL installation to a newer version, did you run the
script? If not, do so. The structure of the grant tables changes occasionally when
mysql_upgrade
new capabilities are added, so after an upgrade you should always make sure that your tables have
the current structure. For instructions, see
MySQL Upgrade".
• If a client program receives the following error message when it tries to connect, it means that the
server expects passwords in a newer format than the client is capable of generating:
shell> mysql
Client does not support authentication protocol requested
by server; consider upgrading MySQL client
For information on how to deal with this, see
Section C.5.2.4, "Client does not support authentication
• Remember that client programs use connection parameters specified in option files or
environment variables. If a client program seems to be sending incorrect default connection
parameters when you have not specified them on the command line, check any applicable option
files and your environment. For example, if you get
any options, make sure that you have not specified an old password in any of your option files!
You can suppress the use of option files by a client program by invoking it with the
[240] option. For example:
defaults
Causes of Access-Denied Errors
--skip-networking
database containing the grant tables. For distributions
mysql
Section 2.18.1, "Unix Postinstallation
mysql_install_db
Accounts".
Section 4.4.9,
Section 6.1.2.4, "Password Hashing in
591
[421], it will not accept TCP/IP
--bind-address=127.0.0.1
Procedures".
mysql
or and is located under your MySQL
data var
user.MYD
script. After running this script and starting the
user has no password initially. That is
root
accounts is something you should do while
root
"mysql_upgrade
protocol".
when you run a client without
Access denied
[401], it will listen
mysql_install_db
directory under the
in the database
mysql
— Check Tables for
MySQL", and
--no-