在LINUX下vsftp建立一个FTP服务器，但通过ftp的命令控制台使用FTP时，ls无法查看目录， 当然更无法上传下载文件了!
出错如下 ：
ftp> ls
227 Entering Passive Mode (192,168,2,222,110,161)150 Here comes the directory listing.
226 Directory send OK.
ftp> ls
200 PORT command successful. Consider using PASV.
150 Here comes the directory listing.
226 Directory send OK.
查看ftp的命令
ftp> help
Commands may be abbreviated. Commands are:
! cr mdir proxy send
$ delete mget sendport site
account debug mkdir put size
append dir mls pwd status
ascii disconnect mode quit struct
bell form modtime quote system
binary get mput recv sunique
bye glob newer reget tenex
case hash nmap rstatus trace
ccc help nlist rhelp type
cd idle ntrans rename user
cdup image open reset umask
chmod lcd passive restart verbose
clear ls private rmdir ?
close macdef prompt runique
cprotect mdelete protect safe
通过 passive 开启和关闭 PASV模式， 再ls 也是同样的问题， 最后在网上找到了解决办法，最重要的是manftpd_selinux，解决这个问题只要：
1.setsebool-Pftpd_disable_trans1
2.servicevsftpdrestart
当然了，解决这个问题的办法还有一个， 就是禁用selinux
如何禁用呢？
vi /etc/sysconfig/selinux
SELINUX=enforcing --> SELINUX=disabled
但是这个修改需要重新启动计算机，reboot 一下。
下面是其他常见的setsebool 命令
BOOLEANS
SELinux policy is based on least privilege required and may also be customizable by setting
a boolean with setsebool.
Allow ftp servers to read and write files with the public_content_rw_t file type.
setsebool -P allow_ftpd_anon_write on
Allow ftp servers to read or write files in the user home directories.
setsebool -P ftp_home_dir on
Allow ftp servers to read or write all files on the system.
setsebool -P allow_ftpd_full_access on
Allow ftp servers to use cifs for public file transfer services.
setsebool -P allow_ftpd_use_cifs on
Allow ftp servers to use nfs for public file transfer services.
setsebool -P allow_ftpd_use_nfs on
system-config-selinux is a GUI tool available to customize SELinux policy settings.
