nginx中http-sysguard模块
防止因nginx并发访问量过高或者遭受攻击造成服务器宕机，可根据负载设置界面跳转。
1.下载模块软件包
wget https://github.com/alibaba/nginx-http-sysguard/archive/master.zipunzip /opt/master.zip
2.给nginx打nginx_sysguard补丁
cd /nginx源文件目录patch -p1 nginx-http-sysguard-master/nginx_sysguard_1.3.9.patch
3.编译nginx添加模块
nginx -V查看nginx编译选项
[root@myhost nginx-1.14.0]# nginx -Vnginx version: nginx/1.14.0built by gcc 4.8.5 20150623 (Red Hat 4.8.5-36) (GCC) built with OpenSSL 1.0.2o 27 Mar 2018TLS SNI support enabledconfigure arguments: --user=www --group=www --prefix=/usr/local/nginx --with-http_stub_status_module --with-http_ssl_module --with-http_v2_module --with-http_gzip_static_module --with-http_sub_module --with-stream --with-stream_ssl_module --with-openssl=/opt/hdlnmp/src/openssl-1.0.2o
重新编译,增加模块
./configure --user=www --group=www --prefix=/usr/local/nginx --with-http_stub_status_module --with-http_ssl_module --with-http_v2_module --with-http_gzip_static_module --with-http_sub_module --with-stream --with-stream_ssl_module --with-openssl=/opt/hdlnmp/src/openssl-1.0.2o --add-module=nginx-http-sysguard-mastermake
替换nginx可执行程序
cp /usr/local/nginx/sbin/nginx /usr/local/nginx/sbin/nginx.bakcp ./objs/nginx /usr/local/nginx/sbin/
4.配置nginx文件
添加如下内容，可在http、server、location段配置，load值根据实际需求自行调节。
sysguard on; sysguard_load load=0.01 action=/loadlimit; sysguard_mem swapratio=20% action=/swaplimit; location = /loadlimit { return 503; } location /swaplimit { return 503; }
可修改配置页面跳转
sysguard on; sysguard_load load=0.01 action=/crowded.html; #sysguard_load load=0.01 action=/error_page/index.html;
5.重启nginx
service nginx restart
crowded.html（放到项目根目录）
!DOCTYPE html html head meta charset="UTF-8" meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0" / meta http-equiv="X-UA-Compatible" content="ie=edge" / title 国家海洋博物馆 /title style type="text/css" .box {position: fixed;top: 50%;left: 50%;transform: translate(-50%, -50%);-ms-transform: translate(-50%, -50%);/* IE 9 */-webkit-transform: translate(-50%, -50%);/* Safari and Chrome */-o-transform: translate(-50%, -50%);/* Opera */-moz-transform: translate(-50%, -50%);/* Firefox */}.box img {display: block;width: 3.85rem;}.box p {font-size: 0.28rem;color: #000;text-align: center;line-height: 1.5rem;} /style /head body div class="box" img src="https://img-blog.csdnimg.cn/2022010617585034894.jpeg" / p 太热情了，请稍后再来吧 /p /div script type="text/javascript" (function(doc, win) {var docEl = doc.documentElement,resizeEvt = 'orientationchange' in window ? 'orientationchange' : 'resize',recalc = function() {var clientWidth = docEl.clientWidth;if(!clientWidth) return;if(clientWidth = 750) {docEl.style.fontSize = '100px';} else {docEl.style.fontSize = 100 * (clientWidth / 750) + 'px';}};if(!doc.addEventListener) return;win.addEventListener(resizeEvt, recalc, false);doc.addEventListener('DOMContentLoaded', recalc, false);})(document, window) /script /body /html
nginx中http-sysguard模块
