An anonymous vsftpd user cannot upload files !? Who knows where the problem is!

An anonymous vsftpd user cannot upload files !? Who knows where the problem is! -- Linux Enterprise Application-Linux server application information. For details, refer to the following section. Anonymous Users cannot upload files.
Configuration file:
Anonymous_enable = YES
# Anon_umask = 022
Local_enable = YES
Write_enable = YES
Local_umask = 022
Anon_upload_enable = YES
Anon_mkdir_write_enable = YES
Dirmessage_enable = YES
Xferlog_enable = YES
Connect_from_port_20 = YES
# Chown_uploads = YES
# Chown_username = whoever
# Xferlog_file =/var/log/vsftpd. log
Xferlog_std_format = YES
# Idle_session_timeout = 600
# Data_connection_timeout = 120
# Nopriv_user = ft1_cure
# Async_abor_enable = YES
Ascii_upload_enable = YES
Ascii_download_enable = YES
Ftpd_banner = Welcome to blah FTP service.
# Deny_email_enable = YES
# Banned_email_file =/etc/vsftpd/banned_emails
# Chroot_list_enable = YES
# Chroot_list_file =/etc/vsftpd/chroot_list
# Ls_recurse_enable = YES
Pam_service_name = vsftpd
Userlist_enable = YES
Listen = YES
Tcp_wrappers = YES
Directory permission:
[Root @ ququ ~] # Ls-l/var/| grep ftp
Drwxr-xr-x 3 root 4096 10-17 ftp
[Root @ ququ ~] # Ls-l/var/ftp
Total 4
Drwxrwxrwx 2 root ftp 4096 10-17 up
Firewall Status:
[Root @ ququ ~] # Cat/etc/selinux/config | grep =
# SELINUX = can take one of these three values:
SELINUX = disabled
# SELINUXTYPE = type of policy in use. Possible values are:
SELINUXTYPE = targeted
[Root @ ququ ~] # Chkconfig -- list | grep iptables
Iptables 0: Disable 1: Disable 2: Enable 3: Enable 4: Enable 5: Enable 6: Disable