搭建ftp服务器
1：首先，更新软件源，保证源是最新的，这样有利于下面在线通过apt-get install命令安装ftp。
2：使用sudo apt-get install vsftp命令安装vsftp，安装软件需要root权限，我们使用sudo来暂时获取。
3：安装好ftp后默认是会自动创建ftp用户的，然后我们设置ftp用户的密码，输入
4：sudo passwd ftp，然后输入密码，再确认密码。
为 ftp用户创建的目录 默认为/srv/ftp
5：对/etc/vsftpd.conf配置文件进行一定的修改。使用 sudo gedit /etc/vsftpd.conf打开配置文件。
将配置文件中”anonymous_enable=YES （是否允许匿名ftp，若不允许选NO）
取消如下配置前的注释符号：
local_enable=YES（是否允许本地用户登录） 27行附近： #本地用户，liyafei ,密码
write_enable=YES（是否允许本地用户写的权限） 29行附近：
chroot_local_user=YES（是否将所有用户限制在主目录） 121行附近：
chroot_list_enable=YES（是否启动限制用户的名单）
chroot_list_file=/etc/vsftpd.chroot_list（可在文件中设置多个账号）
/*********************** /etc/vsftpd.conf ***************************/
# the user does not have write access to the top level directory within the
# chroot)
chroot_local_user=YES
chroot_list_enable=YES
# (default follows)
chroot_list_file=/etc/vsftpd.chroot_list
#chroot_list_file=/etc/chroot_list
然后重启ftp服务，使用命令sudo service vsftpd restart重启ftp服务浏览器通过ftp://192.168.100.91访问成功该目录成功
成功
https://jingyan.baidu.com/article/a948d6512ef9d00a2dcd2ea3.html
通过filezilla进行上传文件
home目录下可以创建很多用户目录。对/etc/vsftpd.conf进行如下配置
userlist_deny=NO
userlist_file=/etc/allowed_users
seccomp_sandbox=NO
local_root=/home/ftp
那么在/etc/allowed_users中的用户就可以通过用户名和密码登录到服务器访问/home/ftp
/etc/allowed_users 文件内容
user1 user2
那么 user1,user2 用户和 本地用户 就可以访问/home/ftp中的内容.
一般哪一个使用哪一个用户名，就访问哪一个用户的主目录，在home目录下面会为每一个用户创建一个目录。
浏览器默认使用ftp用户，访问srv/ftp目录下的内容。就算其它用户在浏览器登录了，也不行。除非将/srv/ftp 目录删除。
用filezilla客户端对文件进行上传，因为/home/ftp中的文件夹都没有写权限，所以进行上传时提示： 553 Could not create file
我们需要在/home/ftp文件夹下创建一个具有写权限的文件夹 ，例如创建文件夹write;
首先在ftp的目录中创建一个目录，然后设置权限为777
$ sudo mkdir /home/ftp/write
$ sudo chmod -R 777 /home/ftp/write
然后修改vsftp的配置文件/etc/vsftpd.conf文件
在最后添加上
local_root=/home/ftp #这是allowed_users 文件夹中的用户访问的路径，上面的配置文件，已经添加过
保存，然后杀死vsftpd进程，然后重启vsftpd服务器程序。
试试看，将文件上传到write目录，这个时候可以正常的上传文件了。
一定要将创建的目录权限修改为可写w，否则提示错误；
响应: 227 Entering Passive Mode (192,168,100,91,84,116).
命令: STOR 网站设计.docx
响应: 553 Could not create file.
错误: 严重文件传输错误
这时就可以向/home/ftp/write 文件夹中上传文件。
如果以user3用户登录，user3用户的目录又在/home/user3 下面，那么使用java客户端上传文件时，路径是从/home/user3开始的。不再加前面的/home/user3
bashPath=/home/usre3就可以省去。
// if (!ftp.changeWorkingDirectory(basePath+filePath)) { if (!ftp.changeWorkingDirectory(filePath)) {
同样，我们也可以在/srv/ftp文件夹中创建 具有写权限的文件夹，供用户名为ftp的用户 进行添加文件。
当想要加载其中的文件时，需要将文件目录所有者root改为使用的用户。 chown -hR liyafei:liyafei ./liyafei
总结：用户名ftp的用户访问/srv/ftp文件夹
本地用户和allowed_users中的用户访问指定的local_root文件夹
如果需要上传功能，需要在文件夹下创建具有写功能的文件夹
在html页面下载ftp服务器内容，通过在连接中指定用户名和密码，和与用户名密码对应的文件位置就可以下载。
例如：下载uftp用户下的/home/ftp/public/file/vsftpd.conf 文件 。uftp用户对应的根目录为/home/ftp，如下所示
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
直接使用一个超链接： ftp://用户名：密码@ip:端口号/该用户下面的目录，省去 local_root 目录。
<a href='ftp://uftp:1367356@192.168.100.91:21/public/file/vsftpd.conf' download="vsftpd"> 点击FTP下载 </a>
</body>
</html>
配置文件：
# Example config file /etc/vsftpd.conf
#
# 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.
#
#
# Run standalone? vsftpd can run either from an inetd or as a standalone
# daemon started from an initscript.
listen=YES
#
# Run standalone with IPv6?
# Like the listen parameter, except vsftpd will listen on an IPv6 socket
# instead of an IPv4 one. This parameter and the listen parameter are mutually
# exclusive.
#listen_ipv6=YES
#
# Allow anonymous FTP? (Disabled by default)
anonymous_enable=YES
#
# 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
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=YES
#
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
anon_mkdir_write_enable=YES
#
anon_other_write_enable=YES
# Activate directory messages - messages given to remote users when they
# go into a certain directory.
dirmessage_enable=YES
#
# If enabled, vsftpd will display directory listings with the time
# in your local time zone. The default is to display GMT. The
# times returned by the MDTM FTP command are also affected by this
# option.
use_localtime=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.
# Note that the default log file location is /var/log/xferlog in this case.
#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=ftpsecure
#
# 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 blah 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 restrict local users to their home directories. See the FAQ for
# the possible risks in this before using chroot_local_user or
# chroot_list_enable below.
#chroot_local_user=YES
#
# 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().
# (Warning! chroot'ing can be very dangerous. If using chroot, make sure that
# the user does not have write access to the top level directory within the
# chroot)
chroot_local_user=YES
chroot_list_enable=NO
# (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
#
# Customization
#
# Some of vsftpd's settings don't fit the filesystem layout by
# default.
#
# This option should be the name of a directory which is empty. Also, the
# directory should not be writable by the ftp user. This directory is used
# as a secure chroot() jail at times vsftpd does not require filesystem
# access.
secure_chroot_dir=/var/run/vsftpd/empty
#
# This string is the name of the PAM service vsftpd will use.
pam_service_name=vsftpd
#
# This option specifies the location of the RSA certificate to use for SSL
# encrypted connections.
rsa_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem
# This option specifies the location of the RSA key to use for SSL
# encrypted connections.
rsa_private_key_file=/etc/ssl/private/ssl-cert-snakeoil.key
userlist_deny=NO
userlist_file=/etc/allowed_users
seccomp_sandbox=NO
#pasv_enable=YES
#pasv_min_port=3000
#pasv_max_port=4000
local_root=/home/ftp
