今天测试vsftp虚拟账户配置，到现在为止还没成功，问题是虚拟账户无法登陆，
查看日志 more /var/log/secure
Mar 23 14:42:26 localhost vsftpd: pam_unix(vsftpd:auth): authentication failure; logname= uid=0 euid=0 tty=ftp ruser=test rhost=192.168.14.24
Mar 23 14:42:26 localhost vsftpd: pam_succeed_if(vsftpd:auth): error retrieving information about user test
Mar 23 14:44:29 localhost vsftpd: PAM unable to dlopen(/lib/security/pam_userdb.so)
Mar 23 14:44:29 localhost vsftpd: PAM [error: /lib/security/pam_userdb.so: wrong ELF class: ELFCLASS32]
Mar 23 14:44:29 localhost vsftpd: PAM adding faulty module: /lib/security/pam_userdb.so
Mar 23 14:44:29 localhost vsftpd: pam_listfile(vsftpd:auth): Couldn't open /etc/vsftpd/wdftp
Mar 23 14:44:29 localhost vsftpd: pam_unix(vsftpd:auth): check pass; user unknown
Mar 23 14:44:29 localhost vsftpd: pam_unix(vsftpd:auth): authentication failure; logname= uid=0 euid=0 tty=ftp ruser=test rhost=192.168.14.24
Mar 23 14:44:29 localhost vsftpd: pam_succeed_if(vsftpd:auth): error retrieving information about user test
下面将我的配置过程写出来，望大家能帮我指正一下,也希望能给后来者一个提示,如有不详细处请回复：
1.环境VirtualBoax **Centos5.5（64位）,**vsftp2.0.5
2.基础软件安装
yum -y install vsftpd*
yum -y install pam*
yum -y install db4*
3.新建useradd wdftp -s /sbin/nologin
4.新建虚拟账户用户文件
vi /etc/vsftpd/vsftpd_login
test
123456
hello
123321ab
5.生成虚拟账户DB文件
db_load -T -t hash -f /etc/vsftpd/vsftpd_login /etc/vsftpd/vsftpd_login.db
6.新建虚拟账户目录/etc/vsftpd/vsftpd_user_conf，并将第4步中用户一一创建一个文件，其中test用户的配置如下，其它账户一样
local_root=/var/ftp/pub/
#anonymous_enable=NO
write_enable=YES
#local_umask=022
#anon_upload_enable=NO
#anon_mkdir_write_enable=NO
#idle_session_timeout=600
#data_connection_timeout=120
#max_clients=10
#max_per_ip=5
#local_max_rate=50000
7.修改vi /etc/pam.d/vsftpd
#%PAM-1.0
auth sufficient /lib64/security/pam_userdb.so db=/etc/vsftpd/vsftpd_login
account sufficient /lib64/security/pam_userdb.so db=/etc/vsftpd/vsftpd_login
session optional pam_keyinit.so force revoke
auth required pam_listfile.so item=user sense=deny file=/etc/vsftpd/wdftp onerr=succeed
auth required pam_shells.so
auth include system-auth
account include system-auth
session include system-auth
session required pam_loginuid.so
8.vsftpd.conf 配置
# The default compiled in settings are fairly paranoid. This sample file
# loosens things up a bit, to make the ftp daemon more usable.
# Please see vsftpd.conf.5 for all compiled in defaults.
#
# READ THIS: This example file is NOT an exhaustive list of vsftpd options.
# Please read the vsftpd.conf.5 manual page to get a full idea of vsftpd's
# capabilities.
#
# Allow anonymous FTP? (Beware - allowed by default if you comment this out).
anonymous_enable=NO
#
# Uncomment this to allow local users to log in.
local_enable=YES
#
# Uncomment this to enable any form of FTP write command.
write_enable=YES
#
# Default umask for local users is 077. You may wish to change this to 022,
# if your users expect that (022 is used by most other ftpd's)
local_umask=022
#
# Uncomment this to allow the anonymous FTP user to upload files. This only
# has an effect if the above global write enable is activated. Also, you will
# obviously need to create a directory writable by the FTP user.
anon_upload_enable=NO
#
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
anon_mkdir_write_enable=NO
#
# Activate directory messages - messages given to remote users when they
# go into a certain directory.
dirmessage_enable=YES
#
# Activate logging of uploads/downloads.
xferlog_enable=YES
#
# Make sure PORT transfer connections originate from port 20 (ftp-data).
connect_from_port_20=YES
#
# If you want, you can arrange for uploaded anonymous files to be owned by
# a different user. Note! Using "root" for uploaded files is not
# recommended!
#chown_uploads=YES
#chown_username=whoever
#
# You may override where the log file goes if you like. The default is shown
# below.
xferlog_file=/var/log/vsftpd.log
#
# If you want, you can have your log file in standard ftpd xferlog format
xferlog_std_format=YES
#
# You may change the default value for timing out an idle session.
#idle_session_timeout=600
#
# You may change the default value for timing out a data connection.
#data_connection_timeout=120
#
# It is recommended that you define on your system a unique user which the
# ftp server can use as a totally isolated and unprivileged user.
nopriv_user=vsftpd
#
# Enable this and the server will recognise asynchronous ABOR requests. Not
# recommended for security (the code is non-trivial). Not enabling it,
# however, may confuse older FTP clients.
async_abor_enable=YES
#
# By default the server will pretend to allow ASCII mode but in fact ignore
# the request. Turn on the below options to have the server actually do ASCII
# mangling on files when in ASCII mode.
# Beware that on some FTP servers, ASCII support allows a denial of service
# attack (DoS) via the command "SIZE /big/file" in ASCII mode. vsftpd
# predicted this attack and has always been safe, reporting the size of the
# raw file.
# ASCII mangling is a horrible feature of the protocol.
ascii_upload_enable=YES
ascii_download_enable=YES
#
# You may fully customise the login banner string:
ftpd_banner=Welcome to FTP service.
#
# You may specify a file of disallowed anonymous e-mail addresses. Apparently
# useful for combatting certain DoS attacks.
#deny_email_enable=YES
# (default follows)
#banned_email_file=/etc/vsftpd/banned_emails
#
# You may specify an explicit list of local users to chroot() to their home
# directory. If chroot_local_user is YES, then this list becomes a list of
# users to NOT chroot().
#chroot_list_enable=YES
# (default follows)
#chroot_list_file=/etc/vsftpd/chroot_list
#
# You may activate the "-R" option to the builtin ls. This is disabled by
# default to avoid remote users being able to cause excessive I/O on large
# sites. However, some broken FTP clients such as "ncftp" and "mirror" assume
# the presence of the "-R" option, so there is a strong case for enabling it.
#ls_recurse_enable=YES
#
# When "listen" directive is enabled, vsftpd runs in standalone mode and
# listens on IPv4 sockets. This directive cannot be used in conjunction
# with the listen_ipv6 directive.
listen=YES
#
# This directive enables listening on IPv6 sockets. To listen on IPv4 and IPv6
# sockets, you must run two copies of vsftpd whith two configuration files.
# Make sure, that one of the listen options is commented !!
#listen_ipv6=YES
chroot_local_user=YES
pam_service_name=vsftpd
userlist_enable=YES
tcp_wrappers=YES
guest_enable=YES
guest_username=wdftp
virtual_use_local_privs=YES
user_config_dir=/etc/vsftpd/vsftpd_user_conf
9.重启service vsftpd restart
我重新将虚拟机中的linux删掉重新装了一篇，然后重新配置vsftp，按上面的步骤成功了！所以流程上是没有问题的，希望能给各位一点参考。
