Linux學習筆記14–架設Apache http伺服器

圖形環境下單擊“Applications → System Settings → Add/Remove Application”功能表項目，
在Server下找的"Web Server"選項，並選中，然後點Update按鈕，按提示安裝。
1-2：
圖1：

圖2：

安裝前需要把載入Linux系統安裝光碟片。
3：
圖3：

安裝好Apache伺服器，可以在命令視窗輸入命令來啟動Apache服務：
[root@CentOS4 ~]# /etc/rc.d/init.d/httpd start
Starting httpd: [  OK  ]
[root@CentOS4 ~]#

啟動之後，初步對HTTP服務進行簡單測試，4：
圖4：

關閉Apache服務：
[root@CentOS4 ~]# /etc/rc.d/init.d/httpd stop
Stopping httpd: [  OK  ]

重新啟動Apache服務：
[root@CentOS4 ~]# /etc/rc.d/init.d/httpd restart
Stopping httpd: [  OK  ]
Starting httpd: [  OK  ]

接下來就簡單瞭解配置HTTP(Apache)伺服器：
設定檔httpd.conf位於/etc/httpd/conf目錄下.

[root@CentOS4 ~]# cat /etc/httpd/conf/httpd.conf
#
# Based upon the NCSA server configuration files originally by Rob McCool.
#
# 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-2.0/> for detailed information about
# the directives.
#
# 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.

... ...

設定檔基本分為三個小節，一個global environment全域環境，一個'main' or 'default' server
主服務/預設伺服器配置，還有一個是Settings for virtual hosts虛擬連接埠配置。

常用配置參數有：
DocumentRoot "/var/www/html"  該參數指定Apache伺服器存放網頁的路徑

圖形介面配置顯示5：
圖5：

MaxClients 118  該參數限制Apache所能提供服務的最高數值，最大可以設定到256。

命令列：
... ...省略部分
# 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
# 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
MaxClients 118
MaxRequestsPerChild 100
</IfModule>
... ...省略部分

圖形介面配置顯示6：
圖6：

Port 80  指定Apache伺服器的監聽連接埠，標準的HTTP伺服器預設連接埠為80。

命令列：
... ...省略部分
# 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
... ...省略部分

圖形介面配置顯示7：
圖7：

ServerName CentOS 設定主機名稱.需要在DNS伺服器註冊該主機名稱才可以使用該名來訪問，不然得指定IP地址。
命令列：
... ...省略部分
# 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 CentOS

... ...省略部分

MaxKeepAliveRequests 100 當使用保持串連(Persistent Connection)功能時，
可以使用本參數決定每次串連所能發出的要求數目的上限.

MaxRequestsPerChild 10  該參數限制每個子進程(Child Process)在結束前所能處理的請求數目，一旦達到該數目，這個子進程就會被中止，以避免長時間佔據Apache(或者Apache伺服器所採用的函數庫)，
防止造成記憶體或者其他系統資源的超負荷。

MaxSpareServers 和MinSpareServers 提供Web服務的HTTP守護進程.

配置Apache時，我們可以選擇圖形介面配置
或者通過修改設定檔httpd.conf參數進行配置。

[完]