有时候为了提高网站后台的安全性，除了后台本身的密码验证外，还可以在apache上设置网站后台目录的密码认证。而有的时候我们需要在一个服务器上运营多个网站，例如，避免服务器资源的浪费，那就可以通过设置apache的虚拟主机来满足项目需求，虚拟主机主要有三种（域名虚拟主机，ip虚拟主机，端口虚拟主机）；
首先安装apache
tar zxf http-2.2.17.tar.gz
cd http-2.2.17
./configure --prefix=/usr/local/httpd --enable-so --enable-rewrite
--enable-charset-lite --enable-cgi
make && make install
/usr/local/httpd/bin/apachectl start
生成加密的http账号密码文件：
/usr/bin/htpasswd -c /usr/local/httpd/conf/.awspwd webadmin
配置apache主配置文件：
<Directory "/usr/local/httpd/htdocs">
Options Indexes FollowSymLinks
AuthNAME "AWStats Directory"
AuthType Basic
AuthUserfile /usr/local/httpd/conf/.awspwd
require valid-user
AllowOverride None
Order allow,deny
Allow from all
</Directory>
重新启动一下服务，通过浏览器验证是否有效
/usr/local/httpd/bin/apachectl restart
基于域名的虚拟主机
ifconfig eth0 20.20.20.1/16
ifconfig eth0:0 20.20.20.3/16
ifconfig eth0:1 20.20.20.4/16
mkdir /usr/local/httpd/htdocs/web1
mkdir /usr/local/httpd/htdocs/web2
echo '<h1>this is web1</h1>' >> /usr/local/httpd/htdocs/web1/index.html
echo '<h1>this is web2</h1>' >> /usr/local/httpd/htdocs/web2/index.html
基于域名的虚拟主机需要域名解析，安装系统光盘的bind服务帮助解析：
mkdir /media/cdrom
mount /dev/cdrom /media/cdrom
rpm -Uvh /media/cdrom/Server/bind-9.3.3-7.el5.i386.rpm
rpm -Uvh /media/cdrom/Server/caching-nameserver-9.3.3-7.el5.i386.rpm
rpm -Uvh /media/cdrom/Server/bind-chroot-9.3.3-7.el5.i386.rpm
cd /var/named/chroot/etc/
cp -p named.caching-nameserver.conf named.conf
vim named.conf
options {
directory "/var/named";
};
zone "jiajia.com" IN {
type master;
file "dragon.com.zone";
};
cd /var/named/chroot/var/named
cp -p localhost.zone dragon.com.zone
vim jiajia.com.zone
$TTL 86400
@ IN SOA dargon.com. admin.dragon.com. (
42 ; serial (d. adams)
3H ; refresh
15M ; retry
1W ; expiry
1D ) ; minimum
IN NS web1.dragon.com
web1 IN A 20.20.20.1
web2 IN A 20.20.20.3
service named restart
echo 'nameserver 20.20.20.1' >/etc/resolv.conf
nslookup web1.dragon.com
nslookup web2.dragon.com
把配置文件写入到httpd.conf里
echo "
namevirtualhost 20.20.20.1
<virtualhost 20.20.20.1>
documentroot /usr/local/httpd/htdocs/web1
servername web1.dragon.com
</virtualhost>
<virtualhost 20.20.20.3>
documentroot /usr/local/httpd/htdocs/web2
servername web2.dragon.com
</virtualhost>
" >>/usr/local/httpd/conf/httpd.conf
/usr/local/httpd/bin/apachectl restart
基于ip地址的虚拟主机：
echo "
<virtualhost 20.20.20.1>
documentroot /usr/local/httpd/htdocs/web1
servername web1.dragon.com
</virtualhost>
<virtualhost 20.20.20.3>
documentroot /usr/local/httpd/htdocs/web2
servername web2.dragon.com
</virtualhost>
" >>/usr/local/httpd/conf/httpd.conf
/usr/local/httpd/bin/apachectl restart
基于端口的虚拟主机
echo "
listen 20.20.20.1:81
listen 20.20.20.1:82
<virtualhost 20.20.20.1:81>
documentroot /usr/local/httpd/htdocs/web1
servername web1.dragon.com
</virtualhost>
<virtualhost 20.20.20.1:82>
documentroot /usr/local/httpd/htdocs/web2
servername web2.dragon.com
</virtualhost>
" >>/usr/local/httpd/conf/httpd.conf
/usr/local/httpd/bin/apachectl restart