[root@Web 3306]# mysql -uroot -p -S /data/3306/mysql.sock
Enter password: 
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
[root@Web 3306]# mysql -uroot -p'oldboy3306' -S /data/3306/mysql.sock
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)

[root@Web ~]# netstat -lnt|grep 330
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN
[root@Web ~]# killall mysqld
[root@Web ~]# killall mysqld
[root@Web ~]# killall mysqld
mysqld: no process killed
[root@Web ~]# mysqld_safe --defaults-file=/data/3306/my.cnf --skip-grant-table &
[1] 6015
140607 15:11:58 mysqld_safe Logging to '/data/3306/mysql_oldboy3306.err'.
140607 15:11:59 mysqld_safe Starting mysqld daemon with databases from /data/3306/data

[root@Web ~]# netstat -lnt|grep 330
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN

[root@Web ~]# mysql -uroot -S /data/3306/mysql.sock
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.1.62-log Source distribution

Copyright (c) 2000, 2011, 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.

mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| oldboy3306 |
| test |
+--------------------+
4 rows in set (0.03 sec)

mysql> select user,host,password from mysql.user;
+------+-----------+-------------------------------------------+
| user | host | password |
+------+-----------+-------------------------------------------+
| root | Web | *007FFCA4271EE782CBEE4DB65344C906C10915BB |
| root | 127.0.0.1 | *007FFCA4271EE782CBEE4DB65344C906C10915BB |
+------+-----------+-------------------------------------------+
2 rows in set (0.00 sec)

mysql> quit
Bye