(编辑:jimmy 日期: 2024/12/27 浏览:2)
负载均衡可以把用户的请求分摊到多个服务器上进行处理,从而实现了对海量用户的访问支持。负载均衡的架构如图所示:
对于复杂的Web应用来说,用Nginx做前端负载均衡是理所当然的事。
下面,我们用Nginx做NodeJS应用的负载均衡。
1、配置Nginx
修改nginx.conf:
upstream sample { server 127.0.0.1:3000; server 127.0.0.1:3001; keepalive 64; } server { listen 80; .... server_name 127.0.0.1; .... location / { proxy_redirect off; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_set_header X-Forwarded-Proto $scheme; proxy_set_header Host $http_host; proxy_set_header X-NginX-Proxy true; proxy_set_header Connection ""; proxy_http_version 1.1; proxy_pass http://sample; } }
这里在3000端口和3001端口各有一个Node.js服务器,这两个服务器在做同样的工作。在upstream节,配置了两个Node.js服务器。此外,我们还设置了proxy_pass http://sample做HTTP请求代理。
2、构建NodeJS服务器
var http = require('http'); var morgan = require('morgan'); var server1 = http.createServer(function (req, res) { console.log("Request for: " + req.url + "-- port 3000 "); res.writeHead(200, {'Content-Type': 'text/plain'}); res.end('Hello Node.js\n'); }).listen(3000, "127.0.0.1"); var server2 = http.createServer(function (req, res) { console.log("Request for: " + req.url + "-- port 3001 "); res.writeHead(200, {'Content-Type': 'text/plain'}); res.end('Hello Node.js\n'); }).listen(3001, "127.0.0.1"); server1.once('listening', function() { console.log('Server running at http://127.0.0.1:3000/'); }); server2.once('listening', function() { console.log('Server running at http://127.0.0.1:3001/'); });
3、访问Nginx服务器
现在我们可以访问http://127.0.0.1
可以看到如下的输出:
Server running at http://127.0.0.1:3000/ Server running at http://127.0.0.1:3001/ Request for: /-- port 3001 Request for: /favicon.ico-- port 3000 Request for: /favicon.ico-- port 3001 Request for: /-- port 3000 Request for: /favicon.ico-- port 3001 Request for: /favicon.ico-- port 3000 Request for: /-- port 3001 Request for: /favicon.ico-- port 3000 Request for: /favicon.ico-- port 3001 Request for: /-- port 3000 Request for: /favicon.ico-- port 3001 Request for: /favicon.ico-- port 3000