全新vps 上 安装 基本的服务 与基本的安全防御

首先,请务必先在虚拟机上先模拟,而后再到vps 上操做 . 大牛请飘过..

本文是以 ubuntu 12.04 LTS server 为例

SSH篇

新建用户且拥有sudo 权限

如下操做以root 用户操做

useradd test

passwd test

cd /home

mkdir test

chown test /home/test

更改 /etc/sudoers 的可读权限

chmod 640 /etc/sudoers 

vi /etc/sudoers 

找到这一 行："root ALL=(ALL) ALL"在起下面添加"xxx ALL=(ALL) ALL"(这里的xxx是你的用户名)
:wq 保存退出

chmod 440 /etc/sudoers

SSH安装与配置

sudo apt-get install openssh-server

安装好后, 接下来就是配置 密钥 验证, 去除密码登入 (防止vps 被 人密码爆破)

如下7个步骤参考自 这里

1. 如下操做请先在虚拟机试验！
2. 建立目录：mkdir ~/.ssh/，并进入这个新目录：cd ~/.ssh/
3. 执行：ssh-keygen -t rsa 或 ssh-keygen -d  产生出 id_rsa, id_rsa.pub两个文件。
4. 重命名：mv id_rsa.pub authorized_keys
5. 注意：.ssh目录的权限必须是700，即除了用户本身，其余人没有任何读写察看该目录的权限，不然ssh服务器会拒绝登陆。ssh默认的公钥文件是用户home目录下的.ssh目录下的authorized_keys文件，所以须要把产生的公钥以这个文件名放到服务器的用户的~/.ssh/目录下。 更改目录权限：chmod 700 ~/.ssh/ 
6. 把id_rsa文件下载到本地，用ssh客户端导入密钥。 
7. 修改/etc/ssh/sshd_config，把下面这两行去掉注释： 
   PubkeyAuthentication  yes
   AuthorizedKeysFile  .ssh/authorized_keys
   再把“PasswordAuthentication yes”改成“PasswordAuthentication no”，执行：/etc/init.d/sshd reload

注意上面第6 步,须要 puttyGen转换成  id_rsa.ppk 才能 引入, 不然 会报这个错误(假如你也用putty 的话)

unable to use key file (openssh ssh-2 private key)

ssh 上传下载命令: 

下载命令 

格式:  scp username@hostIP:文件所在地址   存储的本地文件目录

eg:  

从远程vps 把密钥 下载到本地的home 

 scp swrite@172.16.31.128:/home/swrite/.ssh/id_rsa   ~ 

上传命令

从本地上传 文件到 远程vps

格式: scp 本地文件路径   username@hostIP:目标文件所在地址

 scp ./linux命令  swrite@172.16.31.128:~

禁止root 用户登入

sudo vi /etc/ssh/sshd_config

更改  
PermitRootLogin no

FTP篇

安装vsftp

sudo apt-get install vsftpd

配置 vsftp

通常配置 也就 那么几个须要更改的

listen=YES       # 服务器监听
anonymous_enable=YES       # 匿名访问容许
local_enable=YES    # 本地主机访问容许
write_enable=YES    # 写容许
anon_upload_enable=YES

anon_mkdir_write_enable=YES  # 匿名建立文件夹容许
dirmessage_enable=YES  # 进入文件夹容许
xferlog_enable=YES   #  ftp 日志记录容许

我把个人配置贴出来吧,可供参考(关闭了匿名访问等权限)

# 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? (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=YES
#
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
anon_mkdir_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=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
#
# 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/private/vsftpd.pem

好了,如今  建立一个ftpuser 的ftp目录  

sudo mkdir  /home/ftp

建立ftp 登入用户:  ftpuser  , ftp 目录为 /home/ftp 

sudo useradd -g ftp -d /home/ftp/ -M ftpuser    

重置密码

sudo passwd ftpuser

改变  /home/ftp 的 所属用户

sudo chown ftpuser /home/ftp

---ps , 假如 你的  /etc/vsftpd.conf  文件 配置了 以下几项

chroot_local_user=YES
chroot_list_enable=YES
# (default follows)
chroot_list_file=/etc/vsftpd.chroot_list

须要 建立  /etc/vsftpd.chroot_list 文件 , 并把 你的ftpuser  添加进去（ftp 用户控制）

touch /etc/vsftpd.chroot_list 

而后把你建立的用户添加进去, 每一个用户一行 

 好了, 你ftp 配置完成

防火墙篇 

哎呀, 忽然困了.. 先去睡觉.. 等之后在来写..

不过, 你能够暂时先参考这里, 

1 iptable 基本原理

2 iptable 配置举例

3  如何保证linux 服务器安全

good night ， 早睡早起。