mysql> select user,host,password from test.user;
+------+-----------+-------------------------------------------+
| user | host | password     |
+------+-----------+-------------------------------------------+
| root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 |
+------+-----------+-------------------------------------------+
1 row in set (0.00 sec)

mysql> update test.user set password=password("hello") where user="root" and host="localhost";
Query OK, 1 row affected (0.15 sec)
Rows matched: 1 Changed: 1 Warnings: 0

[root@keepalived01 ~]# mysql -phello
Warning: Using a password on the command line interface can be insecure.
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
[root@keepalived01 ~]# kill -HUP 4283
[root@keepalived01 ~]# mysql -phello
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2528
Server version: 5.6.26 MySQL Community Server (GPL)

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mysql>