Nginx not serving application to the internet-CodePudding

My Nginx and Node.js application is not serving my application to the internet. When I try to access http://helloworld.example.com in my browser it cannot connecf.

Here is my helloworld.conf file:

upstream backend {
        server localhost:8000;
        keepalive 32;
}

server {
        listen 80;
        server_name helloworld.example.com;

        location / {
                client_max_body_size 50M;
                proxy_set_header X-Real-IP $remote_addr;
                proxy_http_version 1.1;
                proxy_pass http://backend;
        }
}

Here is my Node app:

var http = require('http'); 

var hostname = 'localhost';
var port = 8000;

var server = http.createServer((req, res) => {
        res.statusCode = 200;
        res.setHeader('Content-Type', 'text/plain');
        res.end('Hello World!');
});

server.listen(port, hostname, () => {
        console.log(`Server running at http://${hostname}:${port}`);
});

And heres my service file:

[Unit]
Description=Node.js Application
After=syslog.target network.target

[Service]
Type=simple
User=root
WorkingDirectory=/root
Environment=NODE_ENV=production
ExecStart=/usr/bin/node usr/bin/helloworld.js

Restart=always

[Install]
WantedBy=multi-user.target

The service file status shows active and so does the Nginx config file and the node js app run perfectly. Any help?

CodePudding user response：

Try the following configuration, it's from my NGINX server and works fine

server{

    listen 80;

    server_name localhost;

    location / {

        proxy_pass http://localhost:8000;
        proxy_http_version 1.1;
        proxy_set_header   Host               $host:$server_port;
        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;
    }
}

It listens on port 80 of localhost and for every request it receives, it forwards it to http://localhost:8000.

Not specifying anything except proxy_pass will work too

You can learn more about the directives below proxy_pass from the docs here

To connect the application to the internet you just have to change the server_name property in then config assuming that you domain points correctly to your server.

Changing server_name localhost to server_name helloworld.example.com will make the application available on the internet.

CodePudding user response：

To expose your application to the Internet, to host it from home, you need to make changes to systems outside your local machine.

In a typical setup your local computer is not connected to the internet directly. Instead it goes via a router, which is directly connected to the internet.

To the internet you appear with the address of your router and the internet can address your router by it's address. Normally your router "only" forwards your requests to the internet and accepts the responses. (The technical term here is NAT.) But it does not accept any incoming requests, because the router does not know how to handle the request. (Technically the router also blocks the request because it's Firewall is configured reject request.)

   ------------                      ------------- 
  | your local |<--- WiFi / LAN ----| your router |<---- the internet
  |   machine  |----            --->|             |----->
   ------------                      -------------

To make your application available to the internet you will need to tell the router to forward request to your local machine. How this is done depends on your Router, but the keyword here is Port Forwarding.

To forward a port you need to specify the port and the protocol to forward, in case of http this is port 80 (from the listen 80) and protocol TCP (the protocol http uses under the hood). Most routers automatically open this port in the Firewall, but for others you have to explicitly configure it. You most likely also have to open the port 80 in the firewall of your local machine, so the forwarding request is not rejected by your local machine.

If you have set up this forwarding other can now access your application via your routers (IP) address, for example http://91.11.84.87, but not via a domain name (yet).

To get a domain name you typically need to buy/rent (register) a domain name from a domain registrar and "attach" your routers address to the domain. (The keyword being DNS.) Getting a domain name is a story of it's own.

Typically your routers IP address changes regularly, so you will need to also update that address for your domain then! If you are in luck your registrar and router both support DynDNS: This way your router automatically updates the address with your registrar.

I hope this helps you into the right directions.