cmd 下ftp，出现提示： Use PORT or PASV first.
很多地方说是输入pasv 就可以。选择被动模式。
更准确有效的方法是输入： quote pasv.
参考如下：
The FTP server wants to know whether to use a port-mode channel or passive-mode data channel. Most clients will set this up for you transparently (and generally choose passive 'cos it's newer and better). To send a command to the server you use the 'quote' command. Hence if you type:
quote PASV
then it should all work nicely. As an aside, if you type 'remotehelp' then it should show you all the commands that the server can receive - all these can be used with the 'quote' command.
http://www.linuxforums.org/forum/servers/19666-vsftpd-server-425-use-port-pasv-first.html
