有时候，我们需要单独安装nginx，来处理大量的下载请求。单独在Centos5安装nginx遇到的rewrite和HTTP cache错误解决办法：
wget http://nginx.org/download/nginx-0.8.33.tar.gz
tar -zxvf nginx-0.8.33.tar.gz
cd nginx-0.8.33
./configure --prefix=/usr/local/nginx
安装Nginx时报错：
./configure: error: the HTTP rewrite module requires the PCRE library.
安装pcre-devel解决问题：
yum -y install pcre-devel
错误提示：./configure: error: the HTTP cache module requires md5 functions
from OpenSSL library. You can either disable the module by using
--without-http-cache option, or install the OpenSSL library into the system,
or build the OpenSSL library statically from the source with nginx by using
--with-http_ssl_module --with-openssl=<path> options.
解决办法：
yum -y install openssl openssl-devel
总结：
yum -y install pcre-devel openssl openssl-devel
./configure --prefix=/usr/local/nginx
make
make install
一切搞定。