Resolving: ‘Client does not support authentication protocol requested by server’

If you get an error about client authentication version when connecting to MySQL then it may be because your server is using the new password format, while your mysql client (or PHP script, or JDBC code) is using the old password format. See: http://dev.mysql.com/doc/mysql/en/Application_password_use.html.

You can change a new password to an old password like this:

mysql> update user set password = old_password('passwordhere') where user = 'phpbb'; flush privileges;
Query OK, 1 row affected (0.04 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> select user, password from user; +-------+-------------------------------------------+ | user | password | +-------+-------------------------------------------+ | root | *BA3E2F47E409A6ABA83D219D70631A02FE28539E | | root | *BA3E2F47E409A6ABA83D219D70631A02FE28539E | | | | | | | | phpbb | 09a6e3834c6d11c9 | +-------+-------------------------------------------+ 5 rows in set (0.00 sec)

In this case root has a new, longer password. While the phpbb user has the shorter, old password format. In PHP something like mysql_connect(‘localhost’, ‘phpbb’, ‘passwordhere’) should now successfully create a connection. Forgot your MySQL Password?

We all forget passwords at some point. Fortunately you can reset your MySQL password if you forget it.

Add a “skip-grant-tables” line to /etc/my.cnf under the mysqld section.

Restart MySQL:

/etc/init.d/mysql* restart

Set your password to what you like:

mysql -e "update user set password = old_password('newpassword') where user = 'root'" mysql

Remove the skip-grant-tables option from /etc/my.cnf.

Restart MySQL:

/etc/init.d/mysql* restart

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