MySQL 5.7 Reference Manual Including MySQL NDB Cluster 7.5 and NDB Cluster 7.6
        This section describes how to install the
        validate_password password-validation plugin.
        For general information about installing plugins, see
        Section 5.5.1, “Installing and Uninstalling Plugins”.
      
          If you installed MySQL 5.7 using the
          MySQL Yum
          repository,
          MySQL SLES
          Repository, or
          RPM packages provided
          by Oracle, validate_password is
          enabled by default after you start your MySQL Server for the
          first time.
        
        To be usable by the server, the plugin library file must be
        located in the MySQL plugin directory (the directory named by
        the plugin_dir system
        variable). If necessary, configure the plugin directory location
        by setting the value of
        plugin_dir at server startup.
      
        The plugin library file base name is
        validate_password. The file name suffix
        differs per platform (for example, .so for
        Unix and Unix-like systems, .dll for
        Windows).
      
        To load the plugin at server startup, use the
        --plugin-load-add option to name
        the library file that contains it. With this plugin-loading
        method, the option must be given each time the server starts.
        For example, put these lines in the server
        my.cnf file, adjusting the
        .so suffix for your platform as necessary:
      
[mysqld] plugin-load-add=validate_password.so
        After modifying my.cnf, restart the server
        to cause the new settings to take effect.
      
        Alternatively, to load the plugin at runtime, use this
        statement, adjusting the .so suffix for
        your platform as necessary:
      
INSTALL PLUGIN validate_password SONAME 'validate_password.so';
        INSTALL PLUGIN loads the plugin,
        and also registers it in the mysql.plugins
        system table to cause the plugin to be loaded for each
        subsequent normal server startup without the need for
        --plugin-load-add.
      
        To verify plugin installation, examine the Information Schema
        PLUGINS table or use the
        SHOW PLUGINS statement (see
        Section 5.5.2, “Obtaining Server Plugin Information”). For example:
      
mysql>SELECT PLUGIN_NAME, PLUGIN_STATUSFROM INFORMATION_SCHEMA.PLUGINSWHERE PLUGIN_NAME LIKE 'validate%';+-------------------+---------------+ | PLUGIN_NAME | PLUGIN_STATUS | +-------------------+---------------+ | validate_password | ACTIVE | +-------------------+---------------+
If the plugin fails to initialize, check the server error log for diagnostic messages.
        If the plugin has been previously registered with
        INSTALL PLUGIN or is loaded with
        --plugin-load-add, you can use
        the --validate-password option at server
        startup to control plugin activation. For example, to load the
        plugin at startup and prevent it from being removed at runtime,
        use these options:
      
[mysqld] plugin-load-add=validate_password.so validate-password=FORCE_PLUS_PERMANENT
        If it is desired to prevent the server from running without the
        password-validation plugin, use
        --validate-password with a value
        of FORCE or
        FORCE_PLUS_PERMANENT to force server startup
        to fail if the plugin does not initialize successfully.