nginx负载均衡

upstream是Nginx的HTTP Upstream模块，这个模块通过一个简单的调度算法来实现客户端IP到后端服务器的负载均衡

Upstream常用参数介绍

语法：server address [parameters]

其中关键字server必选。 address也必选，可以是主机名、域名、ip或unix socket，也可以指定端口号。 parameters是可选参数，可以是如下参数：

down：表示当前server已停用

backup：表示当前server是备用服务器，只有其它非backup后端服务器都挂掉了或者很忙才会分配到请求

weight：表示当前server负载权重，权重越大被请求几率越大。默认是1

max_fails和fail_timeout一般会关联使用，如果某台server在fail_timeout时间内出现了max_fails次连接失败，那么Nginx会认为其已经挂掉了，从而在fail_timeout时间内不再去请求它，fail_timeout默认是10s，max_fails默认是1，即默认情况是只要发生错误就认为服务器挂掉了，如果将max_fails设置为0，则表示取消这项检查。

ups支持的调度算法

ip_hash  根据ip的hash值来做转发

默认是轮询机制

权重 weight=x

fair 根据服务器的响应时间来分配请求

url_hash

综合案例

nginx.conf

http {
    include       mime.types;
    default_type  application/octet-stream;

    #log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
    #                  '$status $body_bytes_sent "$http_referer" '
    #                  '"$http_user_agent" "$http_x_forwarded_for"';
          
    #access_log  logs/access.log  main;
        
    sendfile        on;
    #tcp_nopush     on; 
      
    #keepalive_timeout  0;
    keepalive_timeout  65; 
    
    #gzip  on;
    include /usr/local/nginx/conf/conf.d/*.conf;
    
}

proxy.conf

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

        location /nginx {
                proxy_set_header Host $host;
                proxy_set_header interface_version $host;
                proxy_set_header X-Real_IP $remote_addr;
                proxy_pass http://tomcatserver;
        }
}

upstream.conf

upstream tomcatserver {
        server 192.168.10.68:8080 weight=10;
        server 192.168.10.69:8080 weight=10;
}

创建nginx.war部署到tomcat下

NginxController

package com.example.springbootnginxdemo;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.net.UnknownHostException;
import java.util.*;

/**
 * @ClassName NginxController
 * @Description: TODO
 * @Author mc
 * @Date 2020
 * @Version V1.0
 **/
@RestController
public class NginxController {

    @GetMapping("/getIp")
    public Object getNginxParam(HttpServletRequest request){
        String remoteAddr = request.getRemoteAddr();
        String ngip = request.getHeader("X-Real_IP");
        String param = request.getHeader("interface_version");
        List<String> addrs = test2();

        Map<String,Object> map = new HashMap<>();
        map.put("remoteAddr",remoteAddr);
        map.put("ngip",ngip);
        map.put("param",param);
        map.put("addrs",addrs);
        return map;
    }
    public List<String> test2() {
        List<String> addrs = new ArrayList<>();
        try {
            Enumeration<NetworkInterface> faces = NetworkInterface.getNetworkInterfaces();
            while (faces.hasMoreElements()) { // 遍历网络接口
                NetworkInterface face = faces.nextElement();
                if (face.isLoopback() || face.isVirtual() || !face.isUp()) {
                    continue;
                }
                //System.out.print("网络接口名：" + face.getDisplayName() + "，地址：");
                Enumeration<InetAddress> address = face.getInetAddresses();
                while (address.hasMoreElements()) { // 遍历网络地址
                    InetAddress addr = address.nextElement();
                    if (!addr.isLoopbackAddress() && addr.isSiteLocalAddress() && !addr.isAnyLocalAddress()) {
                        System.out.print(addr.getHostAddress() + " ");
                        addrs.add(addr.getHostAddress());
                    }
                }
                //System.out.println("");
            }
        } catch (SocketException e) {
            e.printStackTrace();
        }
        return addrs;
    }
}

浏览器访问

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