vsftpd 绑定IP,只对内网开放，更安全。
在vsftpd.conf文件中加入:

listen_address=192.168.102.253

查询配置细节:man vsftpd.conflisten_address    If vsftpd is in standalone mode, the default listen address (of all local interfaces) may be  overridden  by  this    setting. Provide a numeric IP address.    Default: (none)