MySQL root密碼重置報錯：
mysqladmin: connect to server at 'localhost' failed的解決方案
1 登陸失敗,mysqladmin修改密碼失敗
[root@mysql var]# mysqladmin -u root password '123456'
mysqladmin: connect to server at 'localhost' failed
error: 'Access denied for user 'root'@'localhost' (using password: NO)'
2 停止mysql服務
[root@mysql var]# /etc/init.d/mysqld stop
Shutting down MySQL.... SUCCESS!
3 安全模式啟動
[root@mysql var]# mysqld_safe --skip-grant-tables &
（路徑不一樣：/opt/mysql/product/5.5.25a/bin/mysqld_safe --skip-grant-tables &）
[1] 10912
[root@mysql var]# 110407 17:39:28 mysqld_safe Logging to '/usr/local/mysql/var//mysql.chinascopefinanical.com.err'.
110407 17:39:29 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var/
4 無密碼root帳號登陸
[root@mysql var]# /usr/bin/mysql -u root -p 【注釋，在下面的要求你輸入密碼的時候，你不用管，直接回車鍵一敲就過去了】
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 48
Server version: 5.1.41-log Source distribution
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> use mysql;
Database changed
5 手動update修改密碼
mysql> update mysql.user set authentication_string=password("123456") where user='root' and host='localhost';
Query OK, 1 row affected (0.00 sec)
Rows matched: 1 Changed: 1 Warnings: 0
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
mysql> quit
Bye
[root@mysql var]# mysql -u root -p guNNhtqhjUnfky6ahyVh
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 172
Server version: 5.1.41-log Source distribution
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> quit
Bye
6 正常重新啟動
[root@mysql var]# service mysqld restart
Shutting down MySQL..110407 17:45:29 mysqld_safe mysqld from pid file /usr/local/mysql/var//mysql.chinascopefinanical.com.pid ended
SUCCESS!
Starting MySQL.. SUCCESS!