nginx配了https后，后端怎么请求http啊

像这种nginx负载均衡器都是具备https去壳功能，外部请求访问nginx，采用的协议是https，nginx与web服务器是http协议，使用代理就可以了。我贴一个demo配置供参考：

user root root;

worker_processes  8;

error_log /usr/local/nginx/logs/error.log info;

pid     /usr/local/nginx/nginx.pid;

worker_rlimit_nofile 65535;

events {
        use epoll;
        worker_connections  65535;
}

http {
        include       mime.types;
        default_type  application/octet-stream;
        sendfile        on;
        tcp_nopush      on;
        gzip            on;
        keepalive_timeout 30;
        keepalive_requests 10;
        client_header_buffer_size 4k;

        open_file_cache max=65535 inactive=60s;
        open_file_cache_valid 80s;
        open_file_cache_min_uses 1;
        open_file_cache_errors on;


        geo $whiteiplist {
                default 1;

                127.0.0.1/32    0;
                218.245.64.130/32       0;
                101.90.254.10/32        0;
        }
        map $whiteiplist $limit{
                1 $binary_remote_addr;
                0 "";
        }
        limit_req_zone $limit zone=ips:10m rate=20r/m;

        upstream testLB {
                server 192.168.40.4:101 weight=5;
                server 192.168.40.4:102 weight=5;
                server 192.168.40.4:103 weight=5;

                check interval=3000 rise=2 fall=5 timeout=1000 type=http;
                check_http_send "GET /hello HTTP/1.0\r\n\r\n";
                check_http_expect_alive http_2xx http_3xx;
        }

        server {
                listen       80;
                server_name  lyf-test-http;

                ssl                  on;
                ssl_certificate      /usr/local/nginx/conf/_.xxx.com.crt;
                ssl_certificate_key  /usr/local/nginx/conf/_.xxx.com.key;
                ssl_session_timeout  5m;
                ssl_protocols  SSLv2 SSLv3 TLSv1;
                ssl_ciphers  HIGH:!aNULL:!MD5;
                ssl_prefer_server_ciphers   on;

                location / {
                        limit_req zone=ips burst=5 nodelay;

                        root   html;
                        index  index.html;
                        proxy_pass http://testLB;
                        proxy_http_version 1.1;
                        proxy_set_header X-Real-IP $remote_addr;
                        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                }
                location /nginx/monitor {
                        allow 218.245.64.130;
                        deny all;
                        access_log off;

                        stub_status on;
                }
                location /nginx/backend/health/check {
                        allow xxx.xxx.xxx.xxx;
                        deny all;
                        access_log off;

                        check_status;
                }
        }
}

功能很全了，包含IP白名单，IP限流，负载均衡，健康检查，真实IP、监控等功能