nginx配置中$http_host、$host、$host:$proxy_port和$host:$server_port区别
1.proxy_set_header设置的请求头是传递给后端服务器的ngixn反向代理中proxy_set_header的设置: proxy_set_header Host$http_host; proxy_set_header X-Real-IP$remote_addr; proxy_set_header X-Forwarded-For$proxy_add_x_forwarded_f