upstream proxy-www.example.com {
             server 192.168.aa.bb;
        }

#        upstream proxy-mail.example.com {
#              server 192.168.aa.cc;
#        }

        upstream proxy-mirror.example.com {
             server 192.168.aa.dd;
        }

#       ##
#       # Logging Settings
#       ##

#       access_log /var/log/nginx/access.log;
#       error_log /var/log/nginx/error.log debug;


server {
        # сначала по книжке, ISBN 978-5-94074-961-5, стр. 99
#       listen 443 default ssl;
        listen 443 ssl;

        # два хостнейма, см. https://habr.com/post/142363/
#        server_name host04.example.com host05.example.com;
#        server_name host06.example.com;

        ssl on;
        #ssl_prefer_server_ciphers on;
        #ssl protocols TLSv1 SSLv3;
        #ssl_ciphers RC4:HIGH:!aNUL:!MD5:@STRENGTH;
        #ssl_session_cache shared:WEB 10m;
        ssl_certificate /path/to/crt.crt;
        ssl_certificate_key /path/to/key.txt;


        location / {
                # http://nginx.org/ru/docs/http/ngx_http_core_module.html#resolver
                # http://nginx.org/ru/docs/http/ngx_http_proxy_module.html#proxy_pass
                # выкинули из DNS-серверов, будем настраивать с помощью групп upstream -- так проще
                # resolver 8.8.8.8;
                # dig -t SOA example.com
                # resolver ns3-l2.nic.ru;
                # https://sysadmin.ru/articles/oshibka-nginx-upstream-sent-too-big-header-while-reading-response-header-from-upstream
                # fastcgi_buffers 16 16k;
                # fastcgi_buffer_size 32k;
                # https://stackoverflow.com/questions/13894386/upstream-too-big-nginx-codeigniter
                proxy_buffer_size   128k;
                proxy_buffers   4 256k;
                proxy_busy_buffers_size   256k;
                # https://serveradmin.ru/nginx-proxy_pass/
                proxy_pass http://proxy-$host;
                proxy_set_header X-FORWARDED-PROTO https;
                proxy_set_header Host $host;
                proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header X-Real-IP $remote_addr;
        }
}
}