Using Nginx for load balancing of NodeJS applications

"Using Nginx for load balancing of NodeJS applications"

Author: chszs, please indicate when reprinting. Blog homepage: http://blog.csdn.net/chszs

Load balancing can allocate user requests to multiple servers for processing, thereby achieving access support for a large number of users. The load balancing architecture is shown in the figure:

For complex web applications, using Nginx for front-end load balancing is a matter of course.

Next, we use Nginx to load balance NodeJS applications.

1. Configure Nginx

Modify 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;
           }
        }

There is a Node.js server on port 3000 and port 3001. These two servers are doing the same job. In the upstream section, two Node.js servers are configured. In addition, we also set proxy_pass http://sample as HTTP request proxy.

2. Build NodeJS server

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. Access Nginx server

Now we can access http://127.0.0.1

You can see the following output:

  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 

The above introduces the use of Nginx for load balancing of NodeJS applications, including the relevant aspects. I hope it will be helpful to friends who are interested in PHP tutorials.