mysql增加新用户无法登陆解决方法

今天安装openstack folsom版本，安装完mysql，为各个服务增加对应的数据库和用户后，发现
无法使用新增的用户登陆mysql。我增加用户的方法如下：
mysql -uroot -p$mysql_pass <<eof
create database nova;
grant all privileges on nova.* to 'nova'@'%' identified by '$mysql_pass';
create database glance;
grant all privileges on glance.* to 'glance'@'%' identified by '$mysql_pass';
create database keystone;
grant all privileges on keystone.* to 'keystone'@'%'identified by '$mysql_pass';
create database cinder;
grant all privileges on cinder.* to 'cinder'@'%'identified by '$mysql_pass';
create database quantum;
grant all privileges on quantum.* to 'quantum'@'%'identified by '$mysql_pass';
flush privileges;
eof
但使用用户登陆失败：
root@controller:~# mysql -h localhost -ukeystone -ppassword
error 1045 (28000): access denied for user 'keystone'@'localhost' (using password: yes)
解决方法：
增加普通用户后，执行：
mysql> use mysql
mysql> delete from user where user='';
mysql> flush privileges;
意思是删除匿名用户。
ok，搞定，enjoy！