我他么傻逼了， tengine/nginx 到底怎么配置，蛤？求纠错

目前使用是正常的，但是我已经搞不清楚 location 到底是干啥的了
limit_req 写在外面，使用完全没有问题，所有页面都能限制
禁止指定 UA 及 UA 为空的访问的 if 却不能写外面，只能 /和 php 各写一个，如果只写 /那就只能首页限制，其他页面照样访问
nginx -t 没有报错
但是逻辑有没有问题？判断顺序对吗

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

    #设置只是用 https        
    #add_header Strict-Transport-Security "max-age=31536000; includeSubDomains";

    #记录日志，限制缓存为 1M
    access_log  /var/log/nginx/log/tntsec.log  main buffer=1m;
    #主目录
    root   /var/www/html/tntsec;
    #index
    index  index.php index.html index.htm;

    #系统负载控制
    sysguard on;
     sysguard_load load=10 action=/highload.html;

    #限制并发，白名单
    limit_req_whitelist geo_var_name=white_ip geo_var_value=1;
    #限制并发
    limit_req zone=one burst=5 forbid_action=/nocc.html;
    limit_req zone=two forbid_action=/nocc.html;
    limit_req zone=three burst=5 forbid_action=/nocc.html; 

    #屏蔽指定 IP
    #deny 1.1.1.1;


    #伪静态
    if (!-e $request_filename) {
                 rewrite ^(.*)$ /index.php$1 last;
                         }


    location  / {
    #禁止指定 UA 及 UA 为空的访问
    if ($http_user_agent ~ "FeedDemon|JikeSpider|Indy Library|Alexa Toolbar|AskTbFXTV|AhrefsBot|CrawlDaddy|CoolpadWebkit|Java|Feedly|UniversalFeedParser|ApacheBench|Microsoft URL Control|Swiftbot|ZmEu|oBot|jaunty|Python-urllib|lightDeckReports Bot|YYSpider|DigExt|YisouSpider|HttpClient|MJ12bot|heritrix|EasouSpider|Ezooms|^$" ) {
    access_log off;
         return 403;            
    }

    #判断是不是使用代理访问，使用 CDN 请勿开启
    #if ($http_x_real_ip != $http_x_forwarded_for){
    #                access_log off;
    #                return 403;
    #            }

    #禁止非 GET|HEAD|POST 方式的抓取
    if ($request_method !~ ^(GET|HEAD|POST)$) {
    access_log off;
        return 403;
    }
    }

    location ~ .*\.(css|js|ico|png)(.*) {
                  expires 30d;
                 }
    #       error_page  404              /404.html;
    #       error_page 500 502 503 504 =    /500.html;




    location ~ ^/admin/ {
          deny all;
    }

    location ~ /(usr/uploads|usr/plugins/CommentToMail/cache|usr/plugins/Sitemap/sitemap|usr/plugins/CommentToMail/log)/.*\.(php|php5)?$
    {
    deny all;
    }

    location ~ .*\.php(\/.*)*$ {
    #fastcgi_pass 127.0.0.1:9000;
    #location ~ [^/]\.php(/|$) {
    if ($http_user_agent ~ "FeedDemon|JikeSpider|Indy Library|Alexa Toolbar|AskTbFXTV|AhrefsBot|CrawlDaddy|CoolpadWebkit|Java|Feedly|UniversalFeedParser|ApacheBench|Microsoft URL Control|Swiftbot|ZmEu|oBot|jaunty|Python-urllib|lightDeckReports Bot|YYSpider|DigExt|YisouSpider|HttpClient|MJ12bot|heritrix|EasouSpider|Ezooms|^$" ) {
    access_log off;
        return 403;
    }
    if ($request_method !~ ^(GET|HEAD|POST)$) {
    access_log off;
        return 403;
        }

            fastcgi_split_path_info ^(.+?\.php)(/.*)$;
            fastcgi_pass unix:/dev/shm/fpm-cgi.sock;
            #fastcgi_index index.php;
            fastcgi_param PATH_INFO $fastcgi_path_info; 
            fastcgi_param  PHP_VALUE  "open_basedir=$document_root:/tmp/:/proc/";
            fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
            include fastcgi_params;
            }
    }