环境：Centos7.2
Vsftpd版本：3.0.2
SELinux 已关闭
防火墙已关闭
vconf目录正确，文件名正确
virtusers.db生成正确
虚拟用户用户名与vconf下文件名对应正确
本身这套配置应该没问题，因为已经配置过很多台服务器，都是使用的这套配置，唯独这台服务器，同样的配置，就不行了。
vsftpd.conf配置如下：
anonymous_enable=NO
local_enable=YES
write_enable=YES
local_umask=002
anon_upload_enable=NO
anon_mkdir_write_enable=NO
dirmessage_enable=YES
xferlog_enable=YES
connect_from_port_20=YES
chown_uploads=NO
xferlog_file=/opt/log/vsftpd/vsftpd.log
xferlog_std_format=YES
nopriv_user=vsftpd
async_abor_enable=YES
ascii_upload_enable=YES
ascii_download_enable=YES
ftpd_banner=Welcome to Alex FTP service.
chroot_local_user=YES
chroot_list_enable=NO
ls_recurse_enable=NO
listen=YES
pam_service_name=vsftpd
userlist_enable=YES
tcp_wrappers=YES
guest_enable=YES
guest_username=overlord
virtual_use_local_privs=YES
user_config_dir=/etc/vsftpd/vconf
listen_port=21
pasv_min_port=5000
pasv_max_port=5010
pam.d/vsftpd 配置如下：
#%PAM-1.0
auth sufficient pam_userdb.so db=/etc/vsftpd/virtusers
account sufficient pam_userdb.so db=/etc/vsftpd/virtusers
session optional pam_keyinit.so force revoke
auth required pam_listfile.so item=user sense=deny file=/etc/vsftpd/ftpusers onerr=succeed
auth required pam_shells.so
auth include password-auth
account include password-auth
session required pam_loginuid.so
session include password-auth
FTP报错信息：
[root@debug010000002015 ~]# ftp XXX.29.190.XXX
Connected to XXX.29.190.XXX (XXX.29.190.XXX).
220 Welcome to Alex FTP service.
Name (XXX.29.190.XXX:root): dddboy
331 Please specify the password.
Password:
530 Login incorrect.
Login failed.
ftp> quit
221 Goodbye.
tail -f /var/log/secure 日志如下：
Apr 04 12:41:05 debug020000002019.local.alipay.net vsftpd[25977]: pam_unix(vsftpd:auth): check pass; user unknown
Apr 04 12:41:05 debug020000002019.local.alipay.net vsftpd[25977]: pam_unix(vsftpd:auth): authentication failure; logname= uid=0 euid=0 tty=ftp ruser=dlex rhost=158.147.202.138
Apr 04 14:14:51 debug020000002019.local.alipay.net vsftpd[27069]: pam_unix(vsftpd:auth): check pass; user unknown
Apr 04 14:14:51 debug020000002019.local.alipay.net vsftpd[27069]: pam_unix(vsftpd:auth): authentication failure; logname= uid=0 euid=0 tty=ftp ruser=dlex rhost=158.147.202.138
Apr 04 16:47:16 debug020000002019.local.alipay.net vsftpd[28786]: pam_unix(vsftpd:auth): check pass; user unknown
Apr 04 16:47:16 debug020000002019.local.alipay.net vsftpd[28786]: pam_unix(vsftpd:auth): authentication failure; logname= uid=0 euid=0 tty=ftp ruser=dddboy rhost=debug020000002019.local.alipay.net
Apr 04 16:54:35 debug020000002019.local.alipay.net vsftpd[28888]: pam_unix(vsftpd:auth): check pass; user unknown
Apr 04 16:54:35 debug020000002019.local.alipay.net vsftpd[28888]: pam_unix(vsftpd:auth): authentication failure; logname= uid=0 euid=0 tty=ftp ruser=aa rhost=debug020000002019.local.alipay.net
Apr 04 16:58:06 debug020000002019.local.alipay.net vsftpd[28933]: pam_unix(vsftpd:auth): check pass; user unknown
Apr 04 16:58:06 debug020000002019.local.alipay.net vsftpd[28933]: pam_unix(vsftpd:auth): authentication failure; logname= uid=0 euid=0 tty=ftp ruser=dlex rhost=158.147.202.138
