我的应用背景与参考文献的差不多。
就是在虚拟机里面连接主机，实现文件的上传与下载。
在debian里输入命令
$ ftp 192.168.1.248
Connected to 192.168.1.248.
220-FileZilla Server version 0.9.34 beta
220-written by Tim Kosse (Tim.Kosse@gmx.de)
220 Please visit http://sourceforge.net/projects/filezilla/
Name (192.168.1.248:cherish): xxxx
331 Password required for xxxx
Password:
230 Logged on
Remote system type is UNIX.
ftp> dir
200 Port command successful
150 Opening data channel for directory list.
425 Can't open data connection
自己尝试在Windows里面连接，发现没有问题，于是不会是FileZilla的问题。
搜索 虚拟机 425 Can't open data connection 找到参考文献，文章说用
用man ftp查看帮助：
-p Use passive mode for data transfers. Allows use of ftp in environments
where a firewall prevents connections from the outside world
back to the client machine. Requires that the ftp server support
the PASV command. This is the default if invoked as pftp.
于是用命令 ftp -p 192.168.1.248成功登入
参考文献
http://blog.csdn.net/imshang/archive/2010/04/23/5522158.aspx