访问 http://localhost/phpmyadmin时，出现如下图的错误：MySQL said: Cannot connect: invaild setting.
这个错误花费我不少时间，原来是MySQL的用户名与phpmyadmin设置的用户名不一致。
/opt/lampp/etc/my.cnf
# The MySQL server
[mysqld]
user = nobody
port = 3306
socket = /opt/lampp/var/mysql/mysql.sock
skip-external-locking
key_buffer = 16M
/opt/lampp/phpmyadmin/config.inc.php
/* Authentication type and info */
$cfg['Servers'][$i]['auth_type'] = 'config';
$cfg['Servers'][$i]['user'] = 'root';
$cfg['Servers'][$i]['password'] = '';
$cfg['Servers'][$i]['extension'] = 'mysql';
$cfg['Servers'][$i]['AllowNoPassword'] = true;
将config.inc.php中，[user] ='root' 改为与my.cnf中一致，即[user] = 'nobody'就可以了。
希望能帮到遇到相同问题的同学们。