Failover and recovery mechanism in Nginx load balancing solution
Introduction:
For high-load websites, the use of load balancing is to ensure high availability and One of the important means to improve performance. As a powerful open source web server, Nginx's load balancing function has been widely used. In load balancing, how to implement failover and recovery mechanisms is an important issue that needs to be considered. This article will introduce the failover and recovery mechanism in Nginx load balancing and give specific code examples.
1. Failover mechanism
Failover refers to the ability of the system to seamlessly transfer the load to other normal nodes when one or multiple nodes fail. Nginx provides a variety of failover mechanism configuration options. Here are some commonly used methods.
- Health check-based failover
Nginx’s upstream module provides a failover mechanism based on active health checks. By regularly sending health check requests to the backend server, the availability of the node can be judged and load balancing can be performed based on the check results. When a node fails, Nginx will automatically forward requests to other normal nodes to achieve failover.
The following is an example of a load balancing configuration based on health check:
upstream backend { server backend1.example.com:80; server backend2.example.com:80; check interval=3000 rise=2 fall=3 timeout=1000; } server { listen 80; server_name example.com; location / { proxy_pass http://backend; } }
In the above configuration, a health check request will be sent to the backend server every 3 seconds. When there are two consecutive normal responses, the node is considered to be back to normal; when there are three consecutive abnormal responses, the node is considered to be faulty. Nginx will perform load balancing based on node availability and automatically switch to normal nodes.
- Failover based on active detection
The stream module of Nginx provides a failover mechanism based on active detection. By periodically sending probe requests to the backend server, the availability of nodes can be detected and load balancing can be performed based on the probe results. When a node fails, Nginx will automatically forward the request to other normal nodes to achieve failover.
The following is an example of a load balancing configuration based on active detection:
stream { upstream backend { server backend1.example.com:80; server backend2.example.com:80; check interval=3000 rise=2 fall=3 timeout=1000; } server { listen 80; proxy_pass backend; } }
In the above configuration, a detection request will be sent to the backend server every 3 seconds. When there are two consecutive normal responses, the node is considered to be back to normal; when there are three consecutive abnormal responses, the node is considered to be faulty. Nginx will perform load balancing based on node availability and automatically switch to normal nodes.
2. Failure recovery mechanism
Failure recovery refers to the ability of the system to automatically redistribute the load to the node after a node failure is repaired. Nginx provides a variety of configuration options for failure recovery mechanisms. Here are some commonly used methods.
- Failure recovery based on health check
Nginx’s upstream module also provides a failure recovery mechanism based on active health check. After the node's availability is restored, Nginx will automatically redistribute requests to the node.
The following is an example of a health check-based failure recovery configuration:
upstream backend { server backend1.example.com:80; server backend2.example.com:80; check interval=3000 rise=2 fall=3 timeout=1000; } server { listen 80; server_name example.com; location / { proxy_pass http://backend; } }
In the above configuration, when the availability of a node is restored, Nginx will automatically redistribute requests to the node.
- Weight-based failure recovery
Nginx’s upstream module also provides a weight-based failure recovery mechanism. By setting different weight values for nodes, you can control the load distribution ratio. When the availability of a node is restored, the weight value of the node can be adjusted to gradually return it to normal load status.
The following is an example of a weight-based fault recovery configuration:
upstream backend { server backend1.example.com:80 weight=5; server backend2.example.com:80 weight=1; } server { listen 80; server_name example.com; location / { proxy_pass http://backend; } }
In the above configuration, the weight of the backend server backend1 is 5, and the weight of the backend server backend2 is 1. When the availability of backend1 is restored, its weight value can be adjusted so that it gradually returns to 5 to achieve failure recovery.
Conclusion:
This article introduces the failover and recovery mechanism in the Nginx load balancing solution and gives specific code examples. By properly configuring failover and recovery mechanisms, system availability and performance can be improved. In actual applications, the appropriate configuration method can be selected according to specific needs and scenarios to achieve the optimal load balancing effect.
The above is the detailed content of Failover and recovery mechanism in Nginx load balancing solution. For more information, please follow other related articles on the PHP Chinese website!

本篇文章给大家带来了关于nginx的相关知识,其中主要介绍了nginx拦截爬虫相关的,感兴趣的朋友下面一起来看一下吧,希望对大家有帮助。

高并发系统有三把利器:缓存、降级和限流;限流的目的是通过对并发访问/请求进行限速来保护系统,一旦达到限制速率则可以拒绝服务(定向到错误页)、排队等待(秒杀)、降级(返回兜底数据或默认数据);高并发系统常见的限流有:限制总并发数(数据库连接池)、限制瞬时并发数(如nginx的limit_conn模块,用来限制瞬时并发连接数)、限制时间窗口内的平均速率(nginx的limit_req模块,用来限制每秒的平均速率);另外还可以根据网络连接数、网络流量、cpu或内存负载等来限流。1.限流算法最简单粗暴的

实验环境前端nginx:ip192.168.6.242,对后端的wordpress网站做反向代理实现复杂均衡后端nginx:ip192.168.6.36,192.168.6.205都部署wordpress,并使用相同的数据库1、在后端的两个wordpress上配置rsync+inotify,两服务器都开启rsync服务,并且通过inotify分别向对方同步数据下面配置192.168.6.205这台服务器vim/etc/rsyncd.confuid=nginxgid=nginxport=873ho

nginx php403错误的解决办法:1、修改文件权限或开启selinux;2、修改php-fpm.conf,加入需要的文件扩展名;3、修改php.ini内容为“cgi.fix_pathinfo = 0”;4、重启php-fpm即可。

跨域是开发中经常会遇到的一个场景,也是面试中经常会讨论的一个问题。掌握常见的跨域解决方案及其背后的原理,不仅可以提高我们的开发效率,还能在面试中表现的更加

nginx部署react刷新404的解决办法:1、修改Nginx配置为“server {listen 80;server_name https://www.xxx.com;location / {root xxx;index index.html index.htm;...}”;2、刷新路由,按当前路径去nginx加载页面即可。

nginx禁止访问php的方法:1、配置nginx,禁止解析指定目录下的指定程序;2、将“location ~^/images/.*\.(php|php5|sh|pl|py)${deny all...}”语句放置在server标签内即可。

linux版本:64位centos6.4nginx版本:nginx1.8.0php版本:php5.5.28&php5.4.44注意假如php5.5是主版本已经安装在/usr/local/php目录下,那么再安装其他版本的php再指定不同安装目录即可。安装php#wgethttp://cn2.php.net/get/php-5.4.44.tar.gz/from/this/mirror#tarzxvfphp-5.4.44.tar.gz#cdphp-5.4.44#./configure--pr


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Dreamweaver CS6
Visual web development tools

ZendStudio 13.5.1 Mac
Powerful PHP integrated development environment

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool
