Nginx rush purchase current limiting configuration implementation analysis

  limit_req_zone $server_name zone=sname:10m rate=1r/s; #Limit the server to only one successful access per second #limit_req_zone $binary_remote_addr zone=one:3m rate=1r/s; #Limit IP, only one access per second #limit_req_zone $binary_remote_addr $uri zone=two:3m rate=1r/s; #Limit IP and path without parameters,
    #limit_req_zone $binary_remote_addr $request_uri zone=thre:3m rate=1r/s; #Limit IP and path with parameters server {
    listen 80;
    server_name www.abc.com;
    location / {
        include host/proxy.cnf;
        proxy_pass http://backend;
    }
    location /api/createOrder {
        limit_req zone=sname; #No burst, only one normal request limit_req_status 503; #Set the returned status code to 503
        #limit_req zone=sname burst=5 nodelay; #The maximum concurrency is 5, and real-time processing include host/proxy.cnf;
        proxy_pass http://backend;
        error_page 503 =200 /50x.html; #This is very important. You can set the error status code to 503 and return the result as 200
    }
    location = /50x.html {
        if ($http_user_agent ~* "mobile|android|iPhone|iphone|ios|iOS"){
            #default_type application/json;
            return 200 '{"msg": "The event is too popular, please try again later!","data": {},"code": -1}'; #Set the mobile terminal to return an error message display}
        root html; #If it is a PC, return an HTML page}
    }

#Global configuration limit_req_zone $spider zone=spider:60m rate=200r/m; #Limit the crawler to run 200 times per minute #In a server limit_req zone=spider burst=5 nodelay;
if ($http_user_agent ~* "spider|bot") {
  set $spider $http_user_agent; #Set variables, and limit the speed if you enter here}