Nginx: preconent gradation try_files mirror

        location /aa {
            try_files /system/maintenance.html $uri $uri/index.html $uri.html @last;
        }   
        location @last {
            return 207 'last $uri $request_uri';
        }   
        location /bb {
            try_files $uri $uri/index.html $uri.html =405;
        } 

    server {
        listen 80 default_server;
        server_name *.intrinsic.io;
        error_log logs/e.log info;
        resolver 192.168.8.1;
        location / {
            mirror /mirror;
            mirror_request_body on;
        }   
        location = /mirror {
            #internal;
            proxy_pass http://localhost:2020$request_uri;
            proxy_pass_request_body on;
            #proxy_set_header Content-Length '';
            proxy_set_header X-Origin-URI $request_uri;
        }   
    }