军哥lnmp，自建一个conf，把www.bbb.com反代到www.aaa.com/bbb/

server {
listen 80;
server_name www.aaa.com;

location ^~ /bbb {

#配合subs_filter替换字段。
#subs_filter_types text/css text/xml;
#subs_filter ‘”/?’ ‘”/bbb/?’ gi;
#subs_filter ‘”/Skin/’ ‘”/bbb/Skin/’ gi;
#subs_filter ‘/css/’ ‘/bbb/css/’ gi;
#subs_filter ‘”/images/’ ‘”/bbb/images/’ gi;
#subs_filter ‘”/Up/’ ‘”/bbb/Up/’ gi;

#替换模块，下文详解。

proxy_cache_key “$scheme://$host$request_uri”;
#缓存key规则，用于自动清除缓存。

proxy_cache cache_one;
#缓存区名称，必须与前面定义的相同

proxy_cache_valid 200 304 3h;
proxy_cache_valid 301 3d;
proxy_cache_valid any 10s;
#200 304状态缓存3小时
#301状态缓存3天
#其他状态缓存（如502 404）10秒

proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
#向后端传递访客ip

proxy_set_header Referer http://www.bbb.com;
#强制定义Referer，程序验证判断会用到

proxy_set_header Host www.bbb.com;
#定义主机头

proxy_pass http://www.bbb.com/;
#指定后端ip，可用末尾带斜杠的网址代替

proxy_set_header Accept-Encoding “”;
#清除编码，针对启用zip压缩的网站

proxy_cache_use_stale invalid_header error timeout http_502;
#当后端出现错误、超时、502状态时启用过期缓存
}

启用缓存参考

http://huangshanben.com/articles/2900/

Subs_filter模块使用方法参考

https://github.com/yaoweibin/ngx_http_substitutions_filter_module

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