前言
前段时间因为某些原因,几大主流网盘都无法使用,正好手头上有台闲置的云服务器,于是就想来搭建一个文件下载服务,用户只需通过一个链接就能下载软件。
Apache快速上手
经过调研,发现Ubuntu采用Apache2这个软件就可以快速满足我的需求。
安装Apache2
代码语言:javascript复制apt-get install apache2
安装好之后,启动Apache2服务:
代码语言:javascript复制/etc/init.d/apache2 start
查看启动状态:
代码语言:javascript复制/etc/init.d/apache2 status
然后,访问服务器的公网ip或域名,就可以看到如下界面,此时说明Apache正常工作:
最后在/var/www/html
路径下,删除index.html
,上传自己想要被下载的文件,再次访问,就可以进行下载了。
(注:如果是云服务器,还需要在安全组开放80和443端口号)
同时,也可以通过域名/文件名
的方式直接给别人一个链接,进行下载。
如果有一台单独的服务器用于临时文件的分享,这样很快就搞定了。 下面来继续进行深入研究,考虑更现实的场景。
修改端口号
Apache2默认采用的是80端口号,因此直接通过公网ip或域名就能访问。现实中,很多服务器本身就部署了许多其它服务,80端口号往往被占用,因此就需要将Apache2改成其它访问端口。
修改端口,首先需要修改/etc/apache2/ports.conf
这个文件:
这里吧80改成其它不冲突的端口号,我这里以1024为例
#Listen 80
Listen 1024
<IfModule ssl_module>
Listen 443
</IfModule>
<IfModule mod_gnutls.c>
Listen 443
</IfModule>
然后修改/etc/apache2/sites-available/000-default.conf
#<VirtualHost *:80>
<VirtualHost *:1024>
# The ServerName directive sets the request scheme, hostname and port that
# the server uses to identify itself. This is used when creating
注:这个文件中还有一个DocumentRoot
,修改该参数可以调整文件系统的根路径。
修改完成之后,重启apache2:
代码语言:javascript复制/etc/init.d/apache2 restart
此时,就可以通过访问域名:1024
的形式访问到同样内容,例如我的服务器访问url为http://xdxsb.top:1024
设置访问限制
个人服务器很容易遭到别人的攻击,如果有人开好多线程来反复请求下载,这就将导致流量带宽消耗巨大,甚至会让服务器宕机。因此,长期提供下载服务的服务器必须设置访问限制。
配置文件参数详解
访问限制主要涉及到/etc/apache2/apache2.conf
这个配置文件,首先来对该文件进行解读。
这个文件内容如下:
# This is the main Apache server configuration file. It contains the
# configuration directives that give the server its instructions.
# See http://httpd.apache.org/docs/2.4/ for detailed information about
# the directives and /usr/share/doc/apache2/README.Debian about Debian specific
# hints.
#
#
# Summary of how the Apache 2 configuration works in Debian:
# The Apache 2 web server configuration in Debian is quite different to
# upstream's suggested way to configure the web server. This is because Debian's
# default Apache2 installation attempts to make adding and removing modules,
# virtual hosts, and extra configuration directives as flexible as possible, in
# order to make automating the changes and administering the server as easy as
# possible.
# It is split into several files forming the configuration hierarchy outlined
# below, all located in the /etc/apache2/ directory:
#
# /etc/apache2/
# |-- apache2.conf
# | `-- ports.conf
# |-- mods-enabled
# | |-- *.load
# | `-- *.conf
# |-- conf-enabled
# | `-- *.conf
# `-- sites-enabled
# `-- *.conf
#
#
# * apache2.conf is the main configuration file (this file). It puts the pieces
# together by including all remaining configuration files when starting up the
# web server.
#
# * ports.conf is always included from the main configuration file. It is
# supposed to determine listening ports for incoming connections which can be
# customized anytime.
#
# * Configuration files in the mods-enabled/, conf-enabled/ and sites-enabled/
# directories contain particular configuration snippets which manage modules,
# global configuration fragments, or virtual host configurations,
# respectively.
#
# They are activated by symlinking available configuration files from their
# respective *-available/ counterparts. These should be managed by using our
# helpers a2enmod/a2dismod, a2ensite/a2dissite and a2enconf/a2disconf. See
# their respective man pages for detailed information.
#
# * The binary is called apache2. Due to the use of environment variables, in
# the default configuration, apache2 needs to be started/stopped with
# /etc/init.d/apache2 or apache2ctl. Calling /usr/bin/apache2 directly will not
# work with the default configuration.
# Global configuration
#
#
# ServerRoot: The top of the directory tree under which the server's
# configuration, error, and log files are kept.
#
# NOTE! If you intend to place this on an NFS (or otherwise network)
# mounted filesystem then please read the Mutex documentation (available
# at <URL:http://httpd.apache.org/docs/2.4/mod/core.html#mutex>);
# you will save yourself a lot of trouble.
#
# Do NOT add a slash at the end of the directory path.
#
#ServerRoot "/etc/apache2"
#
# The accept serialization lock file MUST BE STORED ON A LOCAL DISK.
#
#Mutex file:${APACHE_LOCK_DIR} default
#
# The directory where shm and other runtime files will be stored.
#
DefaultRuntimeDir ${APACHE_RUN_DIR}
#
# PidFile: The file in which the server should record its process
# identification number when it starts.
# This needs to be set in /etc/apache2/envvars
#
PidFile ${APACHE_PID_FILE}
#
# Timeout: The number of seconds before receives and sends time out.
#
Timeout 300
#
# KeepAlive: Whether or not to allow persistent connections (more than
# one request per connection). Set to "Off" to deactivate.
#
KeepAlive On
#
# MaxKeepAliveRequests: The maximum number of requests to allow
# during a persistent connection. Set to 0 to allow an unlimited amount.
# We recommend you leave this number high, for maximum performance.
#
MaxKeepAliveRequests 100
#
# KeepAliveTimeout: Number of seconds to wait for the next request from the
# same client on the same connection.
#
KeepAliveTimeout 5
# These need to be set in /etc/apache2/envvars
User ${APACHE_RUN_USER}
Group ${APACHE_RUN_GROUP}
#
# HostnameLookups: Log the names of clients or just their IP addresses
# e.g., www.apache.org (on) or 204.62.129.132 (off).
# The default is off because it'd be overall better for the net if people
# had to knowingly turn this feature on, since enabling it means that
# each client request will result in AT LEAST one lookup request to the
# nameserver.
#
HostnameLookups Off
# ErrorLog: The location of the error log file.
# If you do not specify an ErrorLog directive within a <VirtualHost>
# container, error messages relating to that virtual host will be
# logged here. If you *do* define an error logfile for a <VirtualHost>
# container, that host's errors will be logged there and not here.
#
ErrorLog ${APACHE_LOG_DIR}/error.log
#
# LogLevel: Control the severity of messages logged to the error_log.
# Available values: trace8, ..., trace1, debug, info, notice, warn,
# error, crit, alert, emerg.
# It is also possible to configure the log level for particular modules, e.g.
# "LogLevel info ssl:warn"
#
LogLevel warn
# Include module configuration:
IncludeOptional mods-enabled/*.load
IncludeOptional mods-enabled/*.conf
# Include list of ports to listen on
Include ports.conf
# Sets the default security model of the Apache2 HTTPD server. It does
# not allow access to the root filesystem outside of /usr/share and /var/www.
# The former is used by web applications packaged in Debian,
# the latter may be used for local directories served by the web server. If
# your system is serving content from a sub-directory in /srv you must allow
# access here, or in any related virtual host.
<Directory />
Options FollowSymLinks
AllowOverride None
Require all denied
</Directory>
<Directory /usr/share>
AllowOverride None
Require all granted
</Directory>
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride None
Require all granted
</Directory>
#<Directory /srv/>
# Options Indexes FollowSymLinks
# AllowOverride None
# Require all granted
#</Directory>
# AccessFileName: The name of the file to look for in each directory
# for additional configuration directives. See also the AllowOverride
# directive.
#
AccessFileName .htaccess
#
# The following lines prevent .htaccess and .htpasswd files from being
# viewed by Web clients.
#
<FilesMatch "^.ht">
Require all denied
</FilesMatch>
#
# The following directives define some format nicknames for use with
# a CustomLog directive.
#
# These deviate from the Common Log Format definitions in that they use %O
# (the actual bytes sent including headers) instead of %b (the size of the
# requested file), because the latter makes it impossible to detect partial
# requests.
#
# Note that the use of %{X-Forwarded-For}i instead of %h is not recommended.
# Use mod_remoteip instead.
#
LogFormat "%v:%p %h %l %u %t "%r" %>s %O "%{Referer}i" "%{User-Agent}i"" vhost_combined
LogFormat "%h %l %u %t "%r" %>s %O "%{Referer}i" "%{User-Agent}i"" combined
LogFormat "%h %l %u %t "%r" %>s %O" common
LogFormat "%{Referer}i -> %U" referer
LogFormat "%{User-agent}i" agent
# Include of directories ignores editors' and dpkg's backup files,
# see README.Debian for details.
# Include generic snippets of statements
IncludeOptional conf-enabled/*.conf
# Include the virtual host configurations:
IncludeOptional sites-enabled/*.conf
# vim: syntax=apache ts=4 sw=4 sts=4 sr noet
参数解释:
- PidFile:记录服务器启动进程号的文件
- Timeout:接收和发送前超时秒数
- KeepAlive:是否允许稳固的连接(每个连接有多个请求),设为"Off"则停用
- MaxKeepAliveRequests:在稳固连接期间允许的最大请求数,设为0表示无限制接入
- KeepAliveTimeout:在同一个连接上从同一台客户上接收请求的秒数
- User/Group:运行的用户和组
- HostnameLookups:指定记录用户端的名字还是IP地址 例如,本指令为on时记录主机名,如www.apache.org;为off时记录IP地址,204.62.129.132。默认值为off,这要比设为on好得多,因为如果设为on则每个用户端请求都将会至少造成对 nameserver 进行一次查询。
- ErrorLog:错误日志文件定位
- LogLevel:控制记录在错误日志文件中的日志信息 可选值:debug,info,notice,warn,error,crit,alert,emerg
- Directory:在标签对里面可以设置各文件夹属性
- Options:控制在特定目录中将使用哪些服务器特性
- All:除MultiViews之外的所有特性,这是默认设置
- ExecCG:允许使用mod_cgi执行CGI脚本
- FollowSymLinks:服务器允许在此目录中使用符号连接,如果此配置位于配置段中,则会被忽略
- Includes:允许使用mod_include提供的服务器端包含
- IncludesNOEXEC:允许服务器端包含,但禁用"#exec cmd"和"#exec cgi",但仍可以从ScriptAlias目录使用"#include virtual"虚拟CGI脚本
- Indexes:如果一个映射到目录的URL被请求,而此目录中又没有DirectoryIndex(例如:index.html),那么服务器会返回由mod_autoindex生成的一个格式化后的目录列表
- MultiViews:允许使用mod_negotiation提供内容协商的"多重视图"(MultiViews)
- SymLinksIfOwnerMatch:服务器仅在符号连接与其目的目录或文件的拥有者具有相同的uid时才使用它。 如果此配置出现在配置段中,则将被忽略
- AllowOverride:确定允许存在于.htaccess文件中的指令类型
语法:AllowOverride All|None|directive-type [directive-type]
如果此指令被设置为None ,那么.htaccess文件将被完全忽略。
directive-type可以是下列各组指令之一:
- AuthConfig : 允许使用与认证授权相关的指令
- FileInfo : 允许使用控制文档类型的指令、控制文档元数据的指令、mod_rewrite中的指令、mod_actions中的Action指令
- Indexes : 允许使用控制目录索引的指令
- Limit : 允许使用控制主机访问的指令
- Order:控制默认的访问状态与Allow和Deny指令生效的顺序
- Deny,Allow : Deny指令在Allow指令之前被评估。默认允许所有访问。任何不匹配Deny指令或者匹配Allow指令的客户都被允许访问
- Allow,Deny : Allow指令在Deny指令之前被评估。默认拒绝所有访问。任何不匹配Allow指令或者匹配Deny指令的客户都将被禁止访问
- Mutual-failure : 只有出现在Allow列表并且不出现在Deny列表中的主机才被允许访问。这种顺序与"Order Allow,Deny"具有同样效果
- Allow:控制哪些主机可以访问服务器的该区域。可以根据主机名、IP地址、 IP地址范围或其他环境变量中捕获的客户端请求特性进行控制。 语法:Allow from all|host|env=env-variable [host|env=env-variable]
- Deny:控制哪些主机被禁止访问服务器的该区域。可以根据主机名、IP地址、 IP地址范围或其他环境变量中捕获的客户端请求特性进行控制。 语法:Deny from all|host|env=env-variable [host|env=env-variable]
- Require:访问限制 - all granted:表示允许所有主机访问 - all denied:表示拒绝所有主机访问 - local:表示仅允许本地主机访问 - [not] host <主机名或域名列表>:表示允许或拒绝指定主机或域名访问 - [not] ip <IP地址或网段列表>:表示允许或拒绝指定的IP地址或网段访问
- Options:控制在特定目录中将使用哪些服务器特性
- AccessFileName:设置分布式配置文件的名字,默认为.htaccess 如果为某个目录启用了分布式配置文件功能,那么在向客户端返回其中的文档时,服务器将在这个文档所在的各级目录中查找此配置文件
- <FilesMatch"^.ht">:拒绝对.ht开头文件的访问,以保护.htaccess文件
- LogFormat:定义访问日志的格式
限制连接量
通过上面对配置文件参数的研究,注意到MaxKeepAliveRequests
这个参数限制了对于单个连接最大的访问量为100,因此无需担心单线程脚本反复频繁请求的问题。
那么对于高并发的请求,Apache是否有默认设置的策略呢?也是有的,从2.0开始,apache引入了MPM(Multi-Processing Module,多进程处理模块),MPM有prefork, worker和event这三种模式[4],可以通过下面的命令查看当前apache所采用的模式:
apachectl -V | grep -i mpm
默认采用的应该是event模式。
这个模式的配置文件位于/etc/apache2/mods-availablempm_event.conf
默认参数:
<IfModule mpm_event_module>
StartServers 2
MinSpareThreads 25
MaxSpareThreads 75
ThreadLimit 64
ThreadsPerChild 25
MaxRequestWorkers 150
MaxConnectionsPerChild 0
</IfModule>
参数解释:
- StartServers:启动时进程数
- MinSpareThreads:最小空闲线程数
- MaxSpareThreads:最大空闲线程数
- ThreadLimit:每个进程可以启动的线程数量上限值
- ThreadsPerChild:每个进程可以启动的线程数量
- MaxRequestWorkers:线程数量最大值
- MaxConnectionsPerChild:最大连接数限制
我这里没去调整,先用JMeter来进行一个多线程并发测试: JMeter下载地址:https://jmeter.apache.org/download_jmeter.cgi
解压之后,运行apache-jmeter-5.5/bin/jmeter.bat
,即可启动。
创建一个线程组,我这设置了1000个线程数,时间设为0.01秒
再设置HTTP请求,填写请求域名,端口号,文件路径
测试结果显示,请求失败率为16%,因此我这小破服务器,基本上1000个并发请求都难以满足。
封禁ip
如果面对恶意攻击,那最快解决问题的办法无疑是封禁它的ip,这里尝试一下封禁本机ip,看看是否有效。
首先查询本机ip,直接在百度搜索ip
,即可查询到公网ip,注意这里一定要是公网ip,通过ipconfig
查询出的是内网ip。
修改配置文件:
代码语言:javascript复制vim /etc/apache2/apache2.conf
修改/var/www/
文件内容:
<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride None
<RequireAll>
Require all granted
Require not ip 111.11.81.152
</RequireAll>
</Directory>
重启服务:
代码语言:javascript复制 /etc/init.d/apache2 restart
再次访问,发现权限受限,说明设置成功。
拓展:如果只允许某个固定ip访问,那么可以这样修改:
代码语言:javascript复制<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride None
# Require all granted
Require ip 111.11.82.8
</Directory>
设置账号密码访问
对于某些私密文件,可以进一步配置账号密码进行身份验证。
首先创建一个文件夹用来保存用户信息:
代码语言:javascript复制mkdir -p /usr/local/conf
然后创建用户:
代码语言:javascript复制htpasswd -c /usr/local/conf/.usr zstar
zstar
是我创建的用户名
输入密码后,Apache会以密文方式存储密码,可以通过下面的方式查看用户名和密码密文:
代码语言:javascript复制cat /usr/local/conf/.usr
再次修改配置文件:
代码语言:javascript复制vim /etc/apache2/apache2.conf
修改内容:
代码语言:javascript复制<Directory /var/www/>
Options Indexes FollowSymLinks
AllowOverride All
AuthName "apache"
AuthType Basic
AuthUserFile "/usr/local/conf/.usr"
Require user zstar
</Directory>
重启服务:
代码语言:javascript复制 /etc/init.d/apache2 restart
再次访问,成功弹出登录验证,说明配置成功。
参考
[1]ubuntu搭建http服务器用于下载ubuntu文件:https://blog.csdn.net/yy1695990107/article/details/116976994 [2]Apache2 httpd.conf 配置详解:https://blog.csdn.net/assassinice/article/details/78854139 [3]Apache的访问控制:https://blog.csdn.net/m0_54434140/article/details/122249712 [4]apache2三种模式及参数调优:https://blog.csdn.net/zhihui1017/article/details/54959194