Default Apache - /etc/httpd/conf/httpd.conf - explain

#

# This is the main Apache server configuration file.  It contains the

# configuration directives that give the server its instructions.

# See <URL:http://httpd.apache.org/docs/2.2/> for detailed information.

# In particular, see

# <URL:http://httpd.apache.org/docs/2.2/mod/directives.html>

# for a discussion of each configuration directive.

#

#

# Do NOT simply read the instructions in here without understanding

# what they do.  They're here only as hints or reminders.  If you are unsure

# consult the online docs. You have been warned. 

#

# The configuration directives are grouped into three basic sections:

#  1. Directives that control the operation of the Apache server process as a

#     whole (the 'global environment').

#  2. Directives that define the parameters of the 'main' or 'default' server,

#     which responds to requests that aren't handled by a virtual host.

#     These directives also provide default values for the settings

#     of all virtual hosts.

#  3. Settings for virtual hosts, which allow Web requests to be sent to

#     different IP addresses or hostnames and have them handled by the

#     same Apache server process.

#

# Configuration and logfile names: If the filenames you specify for many

# of the server's control files begin with "/" (or "drive:/" for Win32), the

# server will use that explicit path.  If the filenames do *not* begin

# with "/", the value of ServerRoot is prepended -- so "logs/foo.log"

# with ServerRoot set to "/etc/httpd" will be interpreted by the

# server as "/etc/httpd/logs/foo.log".

#

### Section 1: Global Environment

#

# The directives in this section affect the overall operation of Apache,

# such as the number of concurrent requests it can handle or where it

# can find its configuration files.

#

#

# Don't give away too much information about all the subcomponents

# we are running.  Comment out this line if you don't mind remote sites

# finding out what major optional modules you are running

ServerTokens OS

#在出现错误页的时候是否显示服务器操作系统的名称，ServerTokens Prod为不显示.

#下面是ServerTokens的一些可能的赋值：

#ServerTokens Prod 显示“Server: Apache”

#ServerTokens Major 显示 “Server: Apache/2″

#ServerTokens Minor 显示“Server: Apache/2.2″

#ServerTokens Min 显示“Server: Apache/2.2.17″

#ServerTokens OS 显示 “Server: Apache/2.2.17 (Unix)”

#ServerTokens Full 显示 “Server: Apache/2.2.17 (Unix) PHP/5.3.5″ (如果你这指定任何的值，这个是默认的返回信息)

#

# 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 LockFile documentation

# (available at <URL:http://httpd.apache.org/docs/2.2/mod/mpm_common.html#lockfile>);

# you will save yourself a lot of trouble.

#

# Do NOT add a slash at the end of the directory path.

#

ServerRoot "/etc/httpd"

#用于指定Apache的运行目录，服务启动之后自动将目录改变为当前目录，在后面使用到的所有相对路径都是想对这个目录下.

#

# PidFile: The file in which the server should record its process

# identification number when it starts.  Note the PIDFILE variable in

# /etc/sysconfig/httpd must be set appropriately if this location is

# changed.

#

PidFile run/httpd.pid

#记录httpd守护进程的pid号码，这是系统识别一个进程的方法，系统中httpd进程可以有多个，但这个PID对应的进程是其他的父进程.

#

# Timeout: The number of seconds before receives and sends time out.

#

Timeout 60

#服务器与客户端断开的时间.

#

# KeepAlive: Whether or not to allow persistent connections (more than

# one request per connection). Set to "Off" to deactivate.

#

KeepAlive Off

#是否持续连接（因为每次连接都得三次握手，如果是访问量不大，建议打开此项，如果网站访问量比较大关闭此项比较好），修改为：KeepAlive On 表示允许程序性联机.

#

# 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

#表示一个连接的最大请求数

#

# KeepAliveTimeout: Number of seconds to wait for the next request from the

# same client on the same connection.

#

KeepAliveTimeout 15

#断开连接前的时间.

##

## Server-Pool Size Regulation (MPM specific)

##

# prefork MPM

# StartServers: number of server processes to start

# MinSpareServers: minimum number of server processes which are kept spare

# MaxSpareServers: maximum number of server processes which are kept spare

# ServerLimit: maximum value for MaxClients for the lifetime of the server

# MaxClients: maximum number of server processes allowed to start

# MaxRequestsPerChild: maximum number of requests a server process serves

<IfModule prefork.c>

StartServers       8

MinSpareServers    5

MaxSpareServers   20

ServerLimit      256

MaxClients       256

MaxRequestsPerChild  4000

</IfModule>

#系统默认的模块，表示为每个访问启动一个进程（即当有多个连接公用一个进程的时候，在同一时刻只能有一个获得服务）。

#StartServer开始服务时启动8个进程，最小空闲5个进程，最多空闲20个进程。

#MaxClient限制同一时刻客户端的最大连接请求数量超过的要进入等候队列。

#MaxRequestsPerChild每个进程生存期内允许服务的最大请求数量，0表示永不结束.

# worker MPM

# StartServers: initial number of server processes to start

# MaxClients: maximum number of simultaneous client connections

# MinSpareThreads: minimum number of worker threads which are kept spare

# MaxSpareThreads: maximum number of worker threads which are kept spare

# ThreadsPerChild: constant number of worker threads in each server process

# MaxRequestsPerChild: maximum number of requests a server process serves

<IfModule worker.c>

StartServers         4

MaxClients         300

MinSpareThreads     25

MaxSpareThreads     75

ThreadsPerChild     25

MaxRequestsPerChild  0

</IfModule>

#为Apache配置线程访问，即每对WEB服务访问启动一个线程，这样对内存占用率比较小。

#ServerLimit服务器允许配置进程数的上限。

#ThreadLimit每个子进程可能配置的线程上限

#StartServers启动两个httpd进程，

#MaxClients同时最多能发起250个访问，超过的要进入队列等待，其大小有ServerLimit和#ThreadsPerChild的乘积决定

#ThreadsPerChild每个子进程生存期间常驻执行线程数，子线程建立之后将不再增加

#MaxRequestsPerChild每个进程启动的最大线程数，如达到限制数时进程将结束，如置为0则子线程永不结束

#

# Listen: Allows you to bind Apache to specific IP addresses and/or

# ports, in addition to the default. See also the <VirtualHost>

# directive.

#

# Change this to Listen on specific IP addresses as shown below to

# prevent Apache from glomming onto all bound IP addresses (0.0.0.0)

#

#Listen 12.34.56.78:80

Listen 80

#监听的端口，如有多块网卡，默认监听所有网卡

#

# Dynamic Shared Object (DSO) Support

#

# To be able to use the functionality of a module which was built as a DSO you

# have to place corresponding `LoadModule' lines at this location so the

# directives contained in it are actually available _before_ they are used.

# Statically compiled modules (those listed by `httpd -l') do not need

# to be loaded here.

#

# Example:

# LoadModule foo_module modules/mod_foo.so

#

LoadModule auth_basic_module modules/mod_auth_basic.so

LoadModule auth_digest_module modules/mod_auth_digest.so

LoadModule authn_file_module modules/mod_authn_file.so

LoadModule authn_alias_module modules/mod_authn_alias.so

LoadModule authn_anon_module modules/mod_authn_anon.so

LoadModule authn_dbm_module modules/mod_authn_dbm.so

LoadModule authn_default_module modules/mod_authn_default.so

LoadModule authz_host_module modules/mod_authz_host.so

LoadModule authz_user_module modules/mod_authz_user.so

LoadModule authz_owner_module modules/mod_authz_owner.so

LoadModule authz_groupfile_module modules/mod_authz_groupfile.so

LoadModule authz_dbm_module modules/mod_authz_dbm.so

LoadModule authz_default_module modules/mod_authz_default.so

LoadModule ldap_module modules/mod_ldap.so

LoadModule authnz_ldap_module modules/mod_authnz_ldap.so

LoadModule include_module modules/mod_include.so

LoadModule log_config_module modules/mod_log_config.so

LoadModule logio_module modules/mod_logio.so

LoadModule env_module modules/mod_env.so

LoadModule ext_filter_module modules/mod_ext_filter.so

LoadModule mime_magic_module modules/mod_mime_magic.so

LoadModule expires_module modules/mod_expires.so

LoadModule deflate_module modules/mod_deflate.so

LoadModule headers_module modules/mod_headers.so

LoadModule usertrack_module modules/mod_usertrack.so

LoadModule setenvif_module modules/mod_setenvif.so

LoadModule mime_module modules/mod_mime.so

LoadModule dav_module modules/mod_dav.so

LoadModule status_module modules/mod_status.so

LoadModule autoindex_module modules/mod_autoindex.so

LoadModule info_module modules/mod_info.so

LoadModule dav_fs_module modules/mod_dav_fs.so

LoadModule vhost_alias_module modules/mod_vhost_alias.so

LoadModule negotiation_module modules/mod_negotiation.so

LoadModule dir_module modules/mod_dir.so

LoadModule actions_module modules/mod_actions.so

LoadModule speling_module modules/mod_speling.so

LoadModule userdir_module modules/mod_userdir.so

LoadModule alias_module modules/mod_alias.so

LoadModule substitute_module modules/mod_substitute.so

LoadModule rewrite_module modules/mod_rewrite.so

LoadModule proxy_module modules/mod_proxy.so

LoadModule proxy_balancer_module modules/mod_proxy_balancer.so

LoadModule proxy_ftp_module modules/mod_proxy_ftp.so

LoadModule proxy_http_module modules/mod_proxy_http.so

LoadModule proxy_ajp_module modules/mod_proxy_ajp.so

LoadModule proxy_connect_module modules/mod_proxy_connect.so

LoadModule cache_module modules/mod_cache.so

LoadModule suexec_module modules/mod_suexec.so

LoadModule disk_cache_module modules/mod_disk_cache.so

LoadModule cgi_module modules/mod_cgi.so

LoadModule version_module modules/mod_version.so

#启动时加载的模块

#

# The following modules are not loaded by default:

#

#LoadModule asis_module modules/mod_asis.so

#LoadModule authn_dbd_module modules/mod_authn_dbd.so

#LoadModule cern_meta_module modules/mod_cern_meta.so

#LoadModule cgid_module modules/mod_cgid.so

#LoadModule dbd_module modules/mod_dbd.so

#LoadModule dumpio_module modules/mod_dumpio.so

#LoadModule filter_module modules/mod_filter.so

#LoadModule ident_module modules/mod_ident.so

#LoadModule log_forensic_module modules/mod_log_forensic.so

#LoadModule unique_id_module modules/mod_unique_id.so

#

#

# Load config files from the config directory "/etc/httpd/conf.d".

#

Include conf.d/*.conf

#加载的配置文件

#

# ExtendedStatus controls whether Apache will generate "full" status

# information (ExtendedStatus On) or just basic information (ExtendedStatus

# Off) when the "server-status" handler is called. The default is Off.

#

#ExtendedStatus On

#

# If you wish httpd to run as a different user or group, you must run

# httpd as root initially and it will switch. 

#

# User/Group: The name (or #number) of the user/group to run httpd as.

#  . On SCO (ODT 3) use "User nouser" and "Group nogroup".

#  . On HPUX you may not be able to use shared memory as nobody, and the

#    suggested workaround is to create a user www and use that user.

#  NOTE that some kernels refuse to setgid(Group) or semctl(IPC_SET)

#  when the value of (unsigned)Group is above 60000;

#  don't use Group #-1 on these systems!

#

User apache

Group apache

#启动服务后转换的身份，在启动服务时通常以root身份，然后转换身份，这样增加系统安全.

### Section 2: 'Main' server configuration

#

# The directives in this section set up the values used by the 'main'

# server, which responds to any requests that aren't handled by a

# <VirtualHost> definition.  These values also provide defaults for

# any <VirtualHost> containers you may define later in the file.

#

# All of these directives may appear inside <VirtualHost> containers,

# in which case these default settings will be overridden for the

# virtual host being defined.

#

#

# ServerAdmin: Your address, where problems with the server should be

# e-mailed.  This address appears on some server-generated pages, such

# as error documents.  e.g. admin@your-domain.com

#

ServerAdmin root@localhost

#管理员的邮箱

#

# ServerName gives the name and port that the server uses to identify itself.

# This can often be determined automatically, but we recommend you specify

# it explicitly to prevent problems during startup.

#

# If this is not set to valid DNS name for your host, server-generated

# redirections will not work.  See also the UseCanonicalName directive.

#

# If your host doesn't have a registered DNS name, enter its IP address here.

# You will have to access it by its address anyway, and this will make

# redirections work in a sensible way.

#

#ServerName www.example.com:80

#

# UseCanonicalName: Determines how Apache constructs self-referencing

# URLs and the SERVER_NAME and SERVER_PORT variables.

# When set "Off", Apache will use the Hostname and Port supplied

# by the client.  When set "On", Apache will use the value of the

# ServerName directive.

#

UseCanonicalName Off

#如果客户端提供了主机名和端口，Apache将会使用客户端提供的这些信息来构建自引用URL。这些值与用于实现基于域名的虚拟主机的值相同，并且对于同样的客户端可用。CGI变量SERVER_NAME和SERVER_PORT也会由客户端提供的值来构建.

#

# DocumentRoot: The directory out of which you will serve your

# documents. By default, all requests are taken from this directory, but

# symbolic links and aliases may be used to point to other locations.

#

DocumentRoot "/var/www/html"

#网页文件存放的目录

#

# Each directory to which Apache has access can be configured with respect

# to which services and features are allowed and/or disabled in that

# directory (and its subdirectories).

#

# First, we configure the "default" to be a very restrictive set of

# features. 

#

<Directory />

    Options FollowSymLinks

    AllowOverride None

</Directory>

#对根目录的一个权限的设置

#

# Note that from this point forward you must specifically allow

# particular features to be enabled - so if something's not working as

# you might expect, make sure that you have specifically enabled it

# below.

#

#

# This should be changed to whatever you set DocumentRoot to.

#

<Directory "/var/www/html">

#

# Possible values for the Options directive are "None", "All",

# or any combination of:

#   Indexes Includes FollowSymLinks SymLinksifOwnerMatch ExecCGI MultiViews

#

# Note that "MultiViews" must be named *explicitly* --- "Options All"

# doesn't give it to you.

#

# The Options directive is both complicated and important.  Please see

# http://httpd.apache.org/docs/2.2/mod/core.html#options

# for more information.

#

    Options Indexes FollowSymLinks

#

# AllowOverride controls what directives may be placed in .htaccess files.

# It can be "All", "None", or any combination of the keywords:

#   Options FileInfo AuthConfig Limit

#

    AllowOverride None

#

# Controls who can get stuff from this server.

#

    Order allow,deny

    Allow from all

</Directory>

#对/var/www/html目录的一个权限的设置，options中Indexes表示当网页不存在的时候允许索引显示目录中的文件，FollowSymLinks是否允许访问符号链接文件。有的选项有ExecCGI表是否使用CGI，如Options Includes ExecCGI FollowSymLinks表示允许服务器执行CGI及SSI，禁止列出目录。SymLinksOwnerMatch表示当符号链接的文件和目标文件为同一用户拥有时才允许访问。AllowOverrideNone表示不允许这个目录下的访问控制文件来改变这里的配置，这也意味着不用查看这个目录下的访问控制文件，修改为：AllowOverride All 表示允许.htaccess。Order对页面的访问控制顺序后面的一项是默认选项，如allow，deny则默认是deny，Allowfromall表示允许所有的用户，通过和上一项结合可以控制对网站的访问控制.

#

# UserDir: The name of the directory that is appended onto a user's home

# directory if a ~user request is received.

#

# The path to the end user account 'public_html' directory must be

# accessible to the webserver userid.  This usually means that ~userid

# must have permissions of 711, ~userid/public_html must have permissions

# of 755, and documents contained therein must be world-readable.

# Otherwise, the client will only receive a "403 Forbidden" message.

#

# See also: http://httpd.apache.org/docs/misc/FAQ.html#forbidden

#

<IfModule mod_userdir.c>

    #

    # UserDir is disabled by default since it can confirm the presence

    # of a username on the system (depending on home directory

    # permissions).

    #

    UserDir disabled

    #

    # To enable requests to /~user/ to serve the user's public_html

    # directory, remove the "UserDir disabled" line above, and uncomment

    # the following line instead:

    #

    #UserDir public_html

</IfModule>

#是否允许用户访问其家目录，默认是不允许

#

# Control access to UserDir directories.  The following is an example

# for a site where these directories are restricted to read-only.

#

#<Directory /home/*/public_html>

#    AllowOverride FileInfo AuthConfig Limit

#    Options MultiViews Indexes SymLinksIfOwnerMatch IncludesNoExec

#    <Limit GET POST OPTIONS>

#        Order allow,deny

#        Allow from all

#    </Limit>

#    <LimitExcept GET POST OPTIONS>

#        Order deny,allow

#        Deny from all

#    </LimitExcept>

#</Directory>

#如果允许访问用户的家目录中的网页文件，则取消以上注释，并对其中进行修改

#

# DirectoryIndex: sets the file that Apache will serve if a directory

# is requested.

#

# The index.html.var file (a type-map) is used to deliver content-

# negotiated documents.  The MultiViews Option can be used for the

# same purpose, but it is much slower.

#

DirectoryIndex index.html index.html.var

#指定所要访问的主页的默认主页名字，默认首页文件名为index.html

#

# AccessFileName: The name of the file to look for in each directory

# for additional configuration directives.  See also the AllowOverride

# directive.

#

AccessFileName .htaccess

#定义每个目录下的访问控制文件名，缺省为.htaccess

#

# The following lines prevent .htaccess and .htpasswd files from being

# viewed by Web clients.

#

<Files ~ "^\.ht">

    Order allow,deny

    Deny from all

    Satisfy All

</Files>

#控制不让web上的用户来查看.htpasswd和.htaccess这两个文件

#

# TypesConfig describes where the mime.types file (or equivalent) is

# to be found.

#

TypesConfig /etc/mime.types

#用于设置保存有不同MIME类型数据的文件名

#

# DefaultType is the default MIME type the server will use for a document

# if it cannot otherwise determine one, such as from filename extensions.

# If your server contains mostly text or HTML documents, "text/plain" is

# a good value.  If most of your content is binary, such as applications

# or images, you may want to use "application/octet-stream" instead to

# keep browsers from trying to display binary files as though they are

# text.

#

DefaultType text/plain

#默认的网页的类型

#

# The mod_mime_magic module allows the server to use various hints from the

# contents of the file itself to determine its type.  The MIMEMagicFile

# directive tells the module where the hint definitions are located.

#

<IfModule mod_mime_magic.c>

#   MIMEMagicFile /usr/share/magic.mime

    MIMEMagicFile conf/magic

</IfModule>

#指定判断文件真实MIME类型功能的模块

#

# 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

#当打开此项功能时，在记录日志的时候同时记录主机名，这需要服务器来反向解析域名，增加了服务器的负载，通常不建议开启

#

# EnableMMAP: Control whether memory-mapping is used to deliver

# files (assuming that the underlying OS supports it).

# The default is on; turn this off if you serve from NFS-mounted

# filesystems.  On some systems, turning it off (regardless of

# filesystem) can improve performance; for details, please see

# http://httpd.apache.org/docs/2.2/mod/core.html#enablemmap

#

#EnableMMAP off

#如果httpd在传送过程中需要读取一个文件的内容，它是否可以使用内存映射。如果为on表示如果操作系统支持的话，将使用内存映射。在一些多核处理器的系统上，这可能会降低性能，如果在挂载了NFS的DocumentRoot上如果开启此项功能，可能造成因为分段而造成httpd崩溃

#

# EnableSendfile: Control whether the sendfile kernel support is

# used to deliver files (assuming that the OS supports it).

# The default is on; turn this off if you serve from NFS-mounted

# filesystems.  Please see

# http://httpd.apache.org/docs/2.2/mod/core.html#enablesendfile

#

#EnableSendfile off

#这个指令控制httpd是否可以使用操作系统内核的sendfile支持来将文件发送到客户端。默认情况下，当处理一个请求并不需要访问文件内部的数据时(比如发送一个静态的文件内容)，如果操作系统支持，Apache将使用sendfile将文件内容直接发送到客户端而并不读取文件

#

# 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 logs/error_log

#错误日志存放的位置

#

# LogLevel: Control the number of messages logged to the error_log.

# Possible values include: debug, info, notice, warn, error, crit,

# alert, emerg.

#

LogLevel warn

#Apache日志的级别

#

# The following directives define some format nicknames for use with

# a CustomLog directive (see below).

#

LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\"" combined

LogFormat "%h %l %u %t \"%r\" %>s %b" common

LogFormat "%{Referer}i -> %U" referer

LogFormat "%{User-agent}i" agent

#定义了日志的格式，并用不同的代号表示

# "combinedio" includes actual counts of actual bytes received (%I) and sent (%O); this

# requires the mod_logio module to be loaded.

#LogFormat "%h %l %u %t \"%r\" %>s %b \"%{Referer}i\" \"%{User-Agent}i\" %I %O" combinedio

#

# The location and format of the access logfile (Common Logfile Format).

# If you do not define any access logfiles within a <VirtualHost>

# container, they will be logged here.  Contrariwise, if you *do*

# define per-<VirtualHost> access logfiles, transactions will be

# logged therein and *not* in this file.

#

#CustomLog logs/access_log common

#

# If you would like to have separate agent and referer logfiles, uncomment

# the following directives.

#

#CustomLog logs/referer_log referer

#CustomLog logs/agent_log agent

#

# For a single logfile with access, agent, and referer information

# (Combined Logfile Format), use the following directive:

#

CustomLog logs/access_log combined

#说明日志记录的位置，这里面使用了相对路径，所以ServerRoot需要指出，日志位置就存放在/etc/httpd/logs

#

# Optionally add a line containing the server version and virtual host

# name to server-generated pages (internal error documents, FTP directory

# listings, mod_status and mod_info output etc., but not CGI generated

# documents or custom error documents).

# Set to "EMail" to also include a mailto: link to the ServerAdmin.

# Set to one of:  On | Off | EMail

#

ServerSignature On

#定义当客户请求的网页不存在，或者错误的时候是否提示apache的版本的一些信息

#

# Aliases: Add here as many aliases as you need (with no limit). The format is

# Alias fakename realname

#

# Note that if you include a trailing / on fakename then the server will

# require it to be present in the URL.  So "/icons" isn't aliased in this

# example, only "/icons/".  If the fakename is slash-terminated, then the

# realname must also be slash terminated, and if the fakename omits the

# trailing slash, the realname must also omit it.

#

# We include the /icons/ alias for FancyIndexed directory listings.  If you

# do not use FancyIndexing, you may comment this out.

#

Alias /icons/ "/var/www/icons/"

#定义一些不在DocumentRoot下的文件，而可以将其映射到网页根目录中，这也是访问其他目录的一种方法，但在声明的时候切记目录后面加”/”

<Directory "/var/www/icons">

    Options Indexes MultiViews FollowSymLinks

    AllowOverride None

    Order allow,deny

    Allow from all

</Directory>

#定义对/var/www/icons/的权限，修改为 Options MultiViews FollowSymLinks表示不在浏览器上显示树状目录结构

#

# WebDAV module configuration section.

#

<IfModule mod_dav_fs.c>

    # Location of the WebDAV lock database.

    DAVLockDB /var/lib/dav/lockdb

</IfModule>

#对mod_dav_fs.c模块儿的管理

#

# ScriptAlias: This controls which directories contain server scripts.

# ScriptAliases are essentially the same as Aliases, except that

# documents in the realname directory are treated as applications and

# run by the server when requested rather than as documents sent to the client.

# The same rules about trailing "/" apply to ScriptAlias directives as to

# Alias.

#

ScriptAlias /cgi-bin/ "/var/www/cgi-bin/"

#对CGI模块儿的的别名，与Alias相似。

#

# "/var/www/cgi-bin" should be changed to whatever your ScriptAliased

# CGI directory exists, if you have that configured.

#

<Directory "/var/www/cgi-bin">

    AllowOverride None

    Options None

    Order allow,deny

    Allow from all

</Directory>

#对/var/www/cgi-bin文件夹的管理，方法同上

#

# Redirect allows you to tell clients about documents which used to exist in

# your server's namespace, but do not anymore. This allows you to tell the

# clients where to look for the relocated document.

# Example:

# Redirect permanent /foo http://www.example.com/bar

#Redirect参数是用来重写URL的，当浏览器访问服务器上的一个已经不存在的资源的时候，服务器返回给浏览器新的URL，告诉浏览器从该URL中获取资源。这主要用于原来存在于服务器上的文档改变位置之后，又需要能够使用老URL能访问到原网页

#

# Directives controlling the display of server-generated directory listings.

#

#

# IndexOptions: Controls the appearance of server-generated directory

# listings.

#

IndexOptions FancyIndexing VersionSort NameWidth=* HTMLTable Charset=UTF-8

#

# AddIcon* directives tell the server which icon to show for different

# files or filename extensions.  These are only displayed for

# FancyIndexed directories.

#

AddIconByEncoding (CMP,/icons/compressed.gif) x-compress x-gzip

AddIconByType (TXT,/icons/text.gif) text/*

AddIconByType (IMG,/icons/image2.gif) image/*

AddIconByType (SND,/icons/sound2.gif) audio/*

AddIconByType (VID,/icons/movie.gif) video/*

AddIcon /icons/binary.gif .bin .exe

AddIcon /icons/binhex.gif .hqx

AddIcon /icons/tar.gif .tar

AddIcon /icons/world2.gif .wrl .wrl.gz .vrml .vrm .iv

AddIcon /icons/compressed.gif .Z .z .tgz .gz .zip

AddIcon /icons/a.gif .ps .ai .eps

AddIcon /icons/layout.gif .html .shtml .htm .pdf

AddIcon /icons/text.gif .txt

AddIcon /icons/c.gif .c

AddIcon /icons/p.gif .pl .py

AddIcon /icons/f.gif .for

AddIcon /icons/dvi.gif .dvi

AddIcon /icons/uuencoded.gif .uu

AddIcon /icons/script.gif .conf .sh .shar .csh .ksh .tcl

AddIcon /icons/tex.gif .tex

AddIcon /icons/bomb.gif /core

AddIcon /icons/back.gif ..

AddIcon /icons/hand.right.gif README

AddIcon /icons/folder.gif ^^DIRECTORY^^

AddIcon /icons/blank.gif ^^BLANKICON^^

#

# DefaultIcon is which icon to show for files which do not have an icon

# explicitly set.

#

DefaultIcon /icons/unknown.gif

#

# AddDescription allows you to place a short description after a file in

# server-generated indexes.  These are only displayed for FancyIndexed

# directories.

# Format: AddDescription "description" filename

#

#AddDescription "GZIP compressed document" .gz

#AddDescription "tar archive" .tar

#AddDescription "GZIP compressed tar archive" .tgz

#

# ReadmeName is the name of the README file the server will look for by

# default, and append to directory listings.

#

# HeaderName is the name of a file which should be prepended to

# directory indexes.

ReadmeName README.html

HeaderName HEADER.html

#

# IndexIgnore is a set of filenames which directory indexing should ignore

# and not include in the listing.  Shell-style wildcarding is permitted.

#

IndexIgnore .??* *~ *# HEADER* README* RCS CVS *,v *,t

#当一个HTTP请求的URL为一个目录的时候，服务器返回这个目录中的索引文件，如果目录中不存在索引文件，并且服务器有许可显示目录文件列表的时候，就会显示这个目录中的文件列表，为了使得这个文件列表能具有可理解性，而不仅仅是一个简单的列表，就需要前这些参数。如果使用了IndexOptionsFancyIndexing选项，可以让服务器针对不同的文件引用不同的图标。如果没有就使用DefaultIcon定义缺省图标。同样，使用AddDescription可以为不同类型的文档介入描述

#

# DefaultLanguage and AddLanguage allows you to specify the language of

# a document. You can then use content negotiation to give a browser a

# file in a language the user can understand.

#

# Specify a default language. This means that all data

# going out without a specific language tag (see below) will

# be marked with this one. You probably do NOT want to set

# this unless you are sure it is correct for all cases.

#

# * It is generally better to not mark a page as

# * being a certain language than marking it with the wrong

# * language!

#

# DefaultLanguage nl

#

# Note 1: The suffix does not have to be the same as the language

# keyword --- those with documents in Polish (whose net-standard

# language code is pl) may wish to use "AddLanguage pl .po" to

# avoid the ambiguity with the common suffix for perl scripts.

#

# Note 2: The example entries below illustrate that in some cases

# the two character 'Language' abbreviation is not identical to

# the two character 'Country' code for its country,

# E.g. 'Danmark/dk' versus 'Danish/da'.

#

# Note 3: In the case of 'ltz' we violate the RFC by using a three char

# specifier. There is 'work in progress' to fix this and get

# the reference data for rfc1766 cleaned up.

#

# Catalan (ca) - Croatian (hr) - Czech (cs) - Danish (da) - Dutch (nl)

# English (en) - Esperanto (eo) - Estonian (et) - French (fr) - German (de)

# Greek-Modern (el) - Hebrew (he) - Italian (it) - Japanese (ja)

# Korean (ko) - Luxembourgeois* (ltz) - Norwegian Nynorsk (nn)

# Norwegian (no) - Polish (pl) - Portugese (pt)

# Brazilian Portuguese (pt-BR) - Russian (ru) - Swedish (sv)

# Simplified Chinese (zh-CN) - Spanish (es) - Traditional Chinese (zh-TW)

#

AddLanguage ca .ca

AddLanguage cs .cz .cs

AddLanguage da .dk

AddLanguage de .de

AddLanguage el .el

AddLanguage en .en

AddLanguage eo .eo

AddLanguage es .es

AddLanguage et .et

AddLanguage fr .fr

AddLanguage he .he

AddLanguage hr .hr

AddLanguage it .it

AddLanguage ja .ja

AddLanguage ko .ko

AddLanguage ltz .ltz

AddLanguage nl .nl

AddLanguage nn .nn

AddLanguage no .no

AddLanguage pl .po

AddLanguage pt .pt

AddLanguage pt-BR .pt-br

AddLanguage ru .ru

AddLanguage sv .sv

AddLanguage zh-CN .zh-cn

AddLanguage zh-TW .zh-tw

#添加语言

#

# LanguagePriority allows you to give precedence to some languages

# in case of a tie during content negotiation.

#

# Just list the languages in decreasing order of preference. We have

# more or less alphabetized them here. You probably want to change this.

#

LanguagePriority en ca cs da de el eo es et fr he hr it ja ko ltz nl nn no pl pt pt-BR ru sv zh-CN zh-TW

#Apache支持的语言

#

# ForceLanguagePriority allows you to serve a result page rather than

# MULTIPLE CHOICES (Prefer) [in case of a tie] or NOT ACCEPTABLE (Fallback)

# [in case no accepted languages matched the available variants]

#

ForceLanguagePriority Prefer Fallback

#

# Specify a default charset for all content served; this enables

# interpretation of all content as UTF-8 by default.  To use the

# default browser choice (ISO-8859-1), or to allow the META tags

# in HTML content to override this choice, comment out this

# directive:

#

AddDefaultCharset UTF-8

#默认支持的语言

#

# AddType allows you to add to or override the MIME configuration

# file mime.types for specific file types.

#

#AddType application/x-tar .tgz

#支持的应用如果想支持对php的解析添加这样一行

#

# AddEncoding allows you to have certain browsers uncompress

# information on the fly. Note: Not all browsers support this.

# Despite the name similarity, the following Add* directives have nothing

# to do with the FancyIndexing customization directives above.

#

#AddEncoding x-compress .Z

#AddEncoding x-gzip .gz .tgz

#支持对以.Z和.gz.tgz结尾的文件

# If the AddEncoding directives above are commented-out, then you

# probably should define those extensions to indicate media types:

#

AddType application/x-compress .Z

AddType application/x-gzip .gz .tgz

#添加对上述两种文件的应用

#

#   MIME-types for downloading Certificates and CRLs

#

AddType application/x-x509-ca-cert .crt

AddType application/x-pkcs7-crl    .crl

#

# AddHandler allows you to map certain file extensions to "handlers":

# actions unrelated to filetype. These can be either built into the server

# or added with the Action directive (see below)

#

# To use CGI scripts outside of ScriptAliased directories:

# (You will also need to add "ExecCGI" to the "Options" directive.)

#

#AddHandler cgi-script .cgi

#修改为：AddHandler cgi-script .cgi .pl 表示允许扩展名为.pl的CGI脚本运行

#

# For files that include their own HTTP headers:

#

#AddHandler send-as-is asis

#

# For type maps (negotiated resources):

# (This is enabled by default to allow the Apache "It Worked" page

#  to be distributed in multiple languages.)

#

AddHandler type-map var

#

# Filters allow you to process content before it is sent to the client.

#

# To parse .shtml files for server-side includes (SSI):

# (You will also need to add "Includes" to the "Options" directive.)

#

AddType text/html .shtml

AddOutputFilter INCLUDES .shtml

#添加动态处理类型为server-parsed由服务器预先分析网页内的标记，将标记改为正确的HTML标识

#

# Action lets you define media types that will execute a script whenever

# a matching file is called. This eliminates the need for repeated URL

# pathnames for oft-used CGI file processors.

# Format: Action media/type /cgi-script/location

# Format: Action handler-name /cgi-script/location

#

#

# Customizable error responses come in three flavors:

# 1) plain text 2) local redirects 3) external redirects

#

# Some examples:

#ErrorDocument 500 "The server made a boo boo."

#ErrorDocument 404 /missing.html

#ErrorDocument 404 "/cgi-bin/missing_handler.pl"

#ErrorDocument 402 http://www.example.com/subscription_info.html

#

#当服务器出现404错误的时候，返回missing.html页面

#

# Putting this all together, we can internationalize error responses.

#

# We use Alias to redirect any /error/HTTP_<error>.html.var response to

# our collection of by-error message multi-language collections.  We use

# includes to substitute the appropriate text.

#

# You can modify the messages' appearance without changing any of the

# default HTTP_<error>.html.var files by adding the line:

#

#   Alias /error/include/ "/your/include/path/"

#

# which allows you to create your own set of files by starting with the

# /var/www/error/include/ files and

# copying them to /your/include/path/, even on a per-VirtualHost basis.

#

Alias /error/ "/var/www/error/"

#赋值别名

<IfModule mod_negotiation.c>

<IfModule mod_include.c>

    <Directory "/var/www/error">

        AllowOverride None

        Options IncludesNoExec

        AddOutputFilter Includes html

        AddHandler type-map var

        Order allow,deny

        Allow from all

        LanguagePriority en es de fr

        ForceLanguagePriority Prefer Fallback

    </Directory>

#对/var/www/error网页的权限及操作

#    ErrorDocument 400 /error/HTTP_BAD_REQUEST.html.var

#    ErrorDocument 401 /error/HTTP_UNAUTHORIZED.html.var

#    ErrorDocument 403 /error/HTTP_FORBIDDEN.html.var

#    ErrorDocument 404 /error/HTTP_NOT_FOUND.html.var

#    ErrorDocument 405 /error/HTTP_METHOD_NOT_ALLOWED.html.var

#    ErrorDocument 408 /error/HTTP_REQUEST_TIME_OUT.html.var

#    ErrorDocument 410 /error/HTTP_GONE.html.var

#    ErrorDocument 411 /error/HTTP_LENGTH_REQUIRED.html.var

#    ErrorDocument 412 /error/HTTP_PRECONDITION_FAILED.html.var

#    ErrorDocument 413 /error/HTTP_REQUEST_ENTITY_TOO_LARGE.html.var

#    ErrorDocument 414 /error/HTTP_REQUEST_URI_TOO_LARGE.html.var

#    ErrorDocument 415 /error/HTTP_UNSUPPORTED_MEDIA_TYPE.html.var

#    ErrorDocument 500 /error/HTTP_INTERNAL_SERVER_ERROR.html.var

#    ErrorDocument 501 /error/HTTP_NOT_IMPLEMENTED.html.var

#    ErrorDocument 502 /error/HTTP_BAD_GATEWAY.html.var

#    ErrorDocument 503 /error/HTTP_SERVICE_UNAVAILABLE.html.var

#    ErrorDocument 506 /error/HTTP_VARIANT_ALSO_VARIES.html.var

</IfModule>

</IfModule>

#

# The following directives modify normal HTTP response behavior to

# handle known problems with browser implementations.

#

BrowserMatch "Mozilla/2" nokeepalive

BrowserMatch "MSIE 4\.0b2;" nokeepalive downgrade-1.0 force-response-1.0

BrowserMatch "RealPlayer 4\.0" force-response-1.0

BrowserMatch "Java/1\.0" force-response-1.0

BrowserMatch "JDK/1\.0" force-response-1.0

#设置特殊的参数，以保证对老版本浏览器的兼容，并支持新浏览器的特性

#

# The following directive disables redirects on non-GET requests for

# a directory that does not include the trailing slash.  This fixes a

# problem with Microsoft WebFolders which does not appropriately handle

# redirects for folders with DAV methods.

# Same deal with Apple's DAV filesystem and Gnome VFS support for DAV.

#

BrowserMatch "Microsoft Data Access Internet Publishing Provider" redirect-carefully

BrowserMatch "MS FrontPage" redirect-carefully

BrowserMatch "^WebDrive" redirect-carefully

BrowserMatch "^WebDAVFS/1.[0123]" redirect-carefully

BrowserMatch "^gnome-vfs/1.0" redirect-carefully

BrowserMatch "^XML Spy" redirect-carefully

BrowserMatch "^Dreamweaver-WebDAV-SCM1" redirect-carefully

#

# Allow server status reports generated by mod_status,

# with the URL of http://servername/server-status

# Change the ".example.com" to match your domain to enable.

#

#<Location /server-status>

#    SetHandler server-status

#    Order deny,allow

#    Deny from all

#    Allow from .example.com

#</Location>

#

# Allow remote server configuration reports, with the URL of

#  http://servername/server-info (requires that mod_info.c be loaded).

# Change the ".example.com" to match your domain to enable.

#

#<Location /server-info>

#    SetHandler server-info

#    Order deny,allow

#    Deny from all

#    Allow from .example.com

#</Location>

#

# Proxy Server directives. Uncomment the following lines to

# enable the proxy server:

#

#<IfModule mod_proxy.c>

#ProxyRequests On

#

#<Proxy *>

#    Order deny,allow

#    Deny from all

#    Allow from .example.com

#</Proxy>

#

# Enable/disable the handling of HTTP/1.1 "Via:" headers.

# ("Full" adds the server version; "Block" removes all outgoing Via: headers)

# Set to one of: Off | On | Full | Block

#

#ProxyVia On

#

# To enable a cache of proxied content, uncomment the following lines.

# See http://httpd.apache.org/docs/2.2/mod/mod_cache.html for more details.

#

#<IfModule mod_disk_cache.c>

#   CacheEnable disk /

#   CacheRoot "/var/cache/mod_proxy"

#</IfModule>

#

#</IfModule>

# End of proxy directives.

### Section 3: Virtual Hosts

#

# VirtualHost: If you want to maintain multiple domains/hostnames on your

# machine you can setup VirtualHost containers for them. Most configurations

# use only name-based virtual hosts so the server doesn't need to worry about

# IP addresses. This is indicated by the asterisks in the directives below.

#

# Please see the documentation at

# <URL:http://httpd.apache.org/docs/2.2/vhosts/>

# for further details before you try to setup virtual hosts.

#

# You may use the command line option '-S' to verify your virtual host

# configuration.

#

# Use name-based virtual hosting.

#

#NameVirtualHost *:80

#

# NOTE: NameVirtualHost cannot be used without a port specifier

# (e.g. :80) if mod_ssl is being used, due to the nature of the

# SSL protocol.

#

#

# VirtualHost example:

# Almost any Apache directive may go into a VirtualHost container.

# The first VirtualHost section is used for requests without a known

# server name.

#

#<VirtualHost *:80>

#    ServerAdmin webmaster@dummy-host.example.com

#    DocumentRoot /www/docs/dummy-host.example.com

#    ServerName dummy-host.example.com

#    ErrorLog logs/dummy-host.example.com-error_log

#    CustomLog logs/dummy-host.example.com-access_log common

#</VirtualHost>