mysql 5.7.14安裝完後登陸報錯，意思是密碼過期
[root@mysql]# mysql -u root -p
Enter password:
ERROR 1862 (HY000): Your password has expired.
To log in you must change it using a client that supports expired passwords.
解決辦法：
1.在my.cnf mysqld 部分加入 skip-grant-tables 參數。
[mysqld]
skip-grant-tables
2.重啓mysql數據庫，然後登陸
[root@llmj-mysql-40-115 tools]# mysql -u root -p
Enter password: #這裏直接回車，不需要密碼即可登陸
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.14-log MySQL Community Server (GPL)
Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.=
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
3.查看mysql的用戶狀態password_expired ：
>select host,user,password_expired,account_locked from mysql.user;
+-----------+-----------+------------------+----------------+
| host | user | password_expired | account_locked |
+-----------+-----------+------------------+----------------+
| localhost | root | Y | N |
| localhost | mysql.sys | N | Y |
+-----------+-----------+------------------+----------------+
3 rows in set (0.00 sec)
y說明密碼已經過期，可以改成N,就是未過期
>update mysql.user set password_expired='N';
Query OK, 1 row affected (0.03 sec)
Rows matched: 2 Changed: 1 Warnings: 0
4.然後註釋掉skip-grant-tables參數重啓mysql，用過期的密碼就可以登陸了，登陸之後可以用下面的命令修改密碼
>alter user user() identified by '123456';
Query OK, 0 rows affected (0.03 sec)
>flush privileges;
Query OK, 0 rows affected (0.03 sec)