问题

使用匿名用户从 ftp 客户端登录 vsftp 服务器，尝试上传文件失败并显示错误消息：

# ftp vsftpsrv
Connected to vsftpsrv (10.182.38.176).
220 (vsFTPd 2.0.5)
Name (10.182.38.176:root): anonymous
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> pwd
257 "/"
ftp> ls
227 Entering Passive Mode (10,182,38,176,29,34)
150 Here comes the directory listing.
drwxr-xr-x    2 0        0            4096 Jan 09  2013 pub
226 Directory send OK.
ftp> put vsftpd.txt
mput vsftpd.txt? y
227 Entering Passive Mode (10,182,38,176,182,24)
550 Permission denied.
ftp>

解决方案

默认情况下，匿名用户无法上传文件，也无法通过配置文件限制在 vsftp 服务器上创建目录。

注意：匿名用户无法在 vsftpd "/" 目录下上传文件，首先创建一个子目录作为解决方法。

1. 在 vsftp 服务器上，确保下面的行存在并且没有在 /etc/vsftpd/vsftpd.conf 中注释掉：

anon_upload_enable=YES

注意：如果允许匿名用户创建目录，那么也取消注释“anon_mkdir_write_enable=YES”。

2.在vsftp服务器上，在vsftpd“/”目录下创建子目录/var/ftp/

# mkdir /var/ftp/anon_upload

3. 然后将目录所有权更改为 ftp:root 并将权限更改为 0777：

# chown ftp:root /var/ftp/anon_upload/
# chmod 0777 /var/ftp/anon_upload/
# stat /var/ftp/anon_upload/
  File: `/var/ftp/anon_upload/'
  Size: 4096          Blocks: 8          IO Block: 4096   directory
Device: fc00h/64512d    Inode: 719500      Links: 2
Access: (0777/drwxrwxrwx)  Uid: (   14/     ftp)   Gid: (    0/    root)
Access: 2014-02-25 09:27:47.000000000 -0500
Modify: 2014-02-25 09:26:04.000000000 -0500
Change: 2014-02-25 09:38:17.000000000 -0500

4. 在vsftp服务器上重启vsftpd服务：

# service vsftpd restart
Shutting down vsftpd:                                      [  OK  ]
Starting vsftpd for vsftpd:                                [  OK  ]

5. 从ftp客户端登录vsftp服务器，在新建目录下上传文件：

# ftp vsftpsrv
Connected to vsftpsrv (10.182.38.176).
220 (vsFTPd 2.0.5)
Name (10.182.38.176:root): anonymous
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> pwd
257 "/"
ftp> ls
227 Entering Passive Mode (10,182,38,176,205,23)
150 Here comes the directory listing.
drwxrwxrwx    2 14       0            4096 Nov 25 14:26 anon_upload
drwxr-xr-x    2 0        0            4096 Jan 09  2013 pub
226 Directory send OK.
ftp> cd anon_upload
250 Directory successfully changed.
ftp> put vsftpd.txt
local: vsftpd.txt remote: vsftpd.txt
227 Entering Passive Mode (10,182,38,176,34,113)
150 Ok to send data.
226 File receive OK.
38 bytes sent in 1.3e-05 secs (2923.08 Kbytes/sec)
ftp> ls
227 Entering Passive Mode (10,182,38,176,124,56)
150 Here comes the directory listing.
-rw-------    1 14       50             38 Nov 25 14:39 vsftpd.txt
226 Directory send OK.
ftp>

常见错误：

1. 如果上面的解决方法步骤3没有设置，那么匿名用户上传文件会遇到以下错误：

# ftp vsftpsrv
Connected to vsftpsrv (10.182.38.176).
220 (vsFTPd 2.0.5)
Name (10.182.38.176:root): anonymous
331 Please specify the password.
Password:
230 Login successful.
Remote system type is UNIX.
Using binary mode to transfer files.
ftp> pwd
257 "/"
ftp> ls
227 Entering Passive Mode (10,182,38,176,159,123)
150 Here comes the directory listing.
drwxr-xr-x    2 0        0            4096 Nov 25 14:26 anon_upload
drwxr-xr-x    2 0        0            4096 Jan 09  2013 pub
226 Directory send OK.
ftp> cd anon_upload
250 Directory successfully changed.
ftp> pwd
257 "/anon_upload"
ftp> put vsftpd.txt
local: vsftpd.txt remote: vsftpd.txt
227 Entering Passive Mode (10,182,38,176,179,248)
553 Could not create file.
ftp>

2. 如果授予vsftpd“/”目录0775权限：“#chmod -R 0775 /var/ftp”，那么匿名用户登录会因为安全问题而失败：

# ftp vsftpsrv
Connected to vsftpsrv (10.182.38.176).
220 (vsFTPd 2.0.5)
Name (10.182.38.176:root): anonymous
331 Please specify the password.
Password:
500 OOPS: vsftpd: refusing to run with writable anonymous root
Login failed.
ftp>