Nginx负载均衡配置场景
Nginx实现负载均衡用到了proxy_pass代理模块核心配置, 将客户端请求代理转发至一组upstream虚拟服务池
Nginx upstream虚拟配置语法
Syntax: upstream name { ... }
Default: -
Context: http
//upstream例子
upstream backend {
server backend1.example.com weight=5;
server backend2.example.com:8080;
server unix:/tmp/backend3;
server backup1.example.com:8080 backup;
}
server {
location / {
proxy_pass http://backend;
}
}
1.创建对应html文件
[root@Nginx ~]# mkdir /soft/{code1,code2,code3} -p
[root@Nginx ~]# cat /soft/code1/index.html
<html>
<title> Code1</title>
<body bgcolor="red">
<h1> Code1-8081 </h1>
</body>
</html>
[root@Nginx ~]# cat /soft/code2/index.html
<html>
<title> Coder2</title>
<body bgcolor="blue">
<h1> Code1-8082</h1>
</body>
</html>
[root@Nginx ~]# cat /soft/code3/index.html
<html>
<title> Coder3</title>
<body bgcolor="green">
<h1> Code1-8083</h1>
</body>
</html>
2.建立对应的releserver.conf配置文件
[root@Nginx ~]# cat /etc/nginx/conf.d/releserver.conf
server {
listen 8081;
root /soft/code1;
index index.html;
}
server {
listen 8082;
root /soft/code2;
index index.html;
}
server {
listen 8083;
root /soft/code3;
index index.html;
}
3.配置Nginx反向代理
[root@Nginx ~]# cat /etc/nginx/conf.d/proxy.conf
upstream node {
server 192.168.69.113:8081;
server 192.168.69.113:8082;
server 192.168.69.113:8083;
}
server {
server_name 192.168.69.113;
listen 80;
location / {
proxy_pass http://node;
include proxy_params;
}
}
Nginx负载均衡状态配置
后端服务器在负载均衡调度中的状态
| 状态 | 概述 |
|---|---|
| down | 当前的server暂时不参与负载均衡 |
| backup | 预留的备份服务器 |
| max_fails | 允许请求失败的次数 |
| fail_timeout | 经过max_fails失败后, 服务暂停时间 |
| max_conns | 限制最大的接收连接数 |
测试backup以及down状态
upstream load_pass {
server 192.168.56.11:8001 down;
server 192.168.56.12:8002 backup;
server 192.168.56.13:8003 max_fails=1 fail_timeout=10s;
}
location / {
proxy_pass http://load_pass;
include proxy_params;
}
//关闭8003测试
Nginx负载均衡调度策略
| 调度算法 | 概述 |
|---|---|
| 轮询 | 按时间顺序逐一分配到不同的后端服务器(默认) |
| weight | 加权轮询,weight值越大,分配到的访问几率越高 |
| ip_hash | 每个请求按访问IP的hash结果分配,这样来自同一IP的固定访问一个后端服务器 |
| url_hash | 按照访问URL的hash结果来分配请求,是每个URL定向到同一个后端服务器 |
| least_conn | 最少链接数,那个机器链接数少就分发 |
| hash关键数值 | hash自定义的key |
Nginx负载均衡权重轮询具体配置
upstream load_pass {
server 192.168.56.11:8001;
server 192.168.56.12:8002 weight=5;
server 192.168.56.13:8003;
}
Nginx负载均衡ip_hash具体配置
//如果客户端都走相同代理, 会导致某一台服务器连接过多
upstream load_pass {
ip_hash;
server 192.168.56.11:8001;
server 192.168.56.12:8002;
server 192.168.56.13:8003;
}
//如果出现通过代理访问会影响后端节点接收状态均衡
Nginx负载均衡url_hash具体配置
upstream load_pass {
hash $request_uri;
server 192.168.56.11:8001;
server 192.168.56.12:8002;
server 192.168.56.13:8003;
}
//针对三台服务器添加相同文件
/soft/code1/url1.html url2.html url3.html
/soft/code2/url1.html url2.html url3.html
/soft/code3/url1.html url2.html url3.html
Nginx负载均衡TCP配置
Nginx四层代理仅能存在于main段
stream {
upstream ssh_proxy {
hash $remote_addr consistent;
server 192.168.56.103:22;
}
upstream mysql_proxy {
hash $remote_addr consistent;
server 192.168.56.103:3306;
}
server {
listen 6666;
proxy_connect_timeout 1s;
proxy_timeout 300s;
proxy_pass ssh_proxy;
}
server {
listen 5555;
proxy_connect_timeout 1s;
proxy_timeout 300s;
proxy_pass mysql_proxy;
}
}