This site can’t be reached on Nodejs Express? - node.js

I'm totally new to Node and I tried to run a test site on a hosting centos 7 (vultr.com). I've got nodejs, express installed.
Hello.js
const express = require('express')
const app = express()
app.get('/', function (req, res) {
res.send('Hello World!')
})
app.listen(3000, function () {
console.log('Example app listening on port 3000!')
})
run node hello.js
On my PC, http://x.x.x.x:3000/ => shows This site can’t be reached
x.x.x.x took too long to respond.
UPDATE:

I think you should consider about your server port. Have you open port 3000 in CentOS?
You can check your open port by typing
iptables -L
I think the firewall blocked your port you can open it by type this command
iptables -A INPUT -p tcp --dport 3000 -j ACCEPT

If you are using remote server, probably your 8080 port is blocked.
If you have root access and port 80 is open you can try and run script with sudo
But the first option is probably your problem

If you use the Google Cloud platform, you can open port 3000 at FIREWALL RULES in VPC network.
It works for me.

Related

AWS public ip with port not working for nodejs

I have installed nodejs in aws ubuntu 18.04 version. Added port 3000 in security Group. but node js not working in my public address with port for eg: http://3.xx.xx.xx:3000.
Note: pm2 running with node js
The solution for this is :-
in your backend inside app.js listen on port 3000 or which ever port you wish to.
Go to amazon console, got to security groups associated with your ec2 instance, and under incoming connection add a custom tcp rule with port 3000 and source should be 0.0.0.0/0 and save it
Run netstat -pan | grep 3000 if you noticed that node.js listen on 127.0.0.1 only not 0.0.0.0 so You can't access node.js from outside because it is listening on localhost IP i.e 127.0.0.1.
You need to configure node.js to listen on 0.0.0.0 so it will be able to accept connections on all the IPs of your machine.
For example:
var http = require('http');
http.createServer(function (req, res) {
res.writeHead(200, {'Content-Type': 'text/plain'});
res.end('Hello World\n');
}).listen(3000, "0.0.0.0");
console.log('Server running at http://0.0.0.0:3000/');
last step if you did not already, go to the Security Groups tab in the EC2 console. Right click the security group you setup and click edit inbound rules.
Click Add Rule. This time we are going to use a custom TCP rule on port 3000, open to anywhere.

How to run nodejs on my public ip in windows?

I using windows 10 and want to run nodejs on port 3000 in my public address (just of me and for remote debugging).
So I open the port as say by this answer and I run this code from expressjs
const express = require('express')
const app = express()
const port = 3000
app.get('/', (req, res) => res.send('Hello World!'))
app.listen(port, () => console.log(`Example app listening on port ${port}!`))
Then I get myip address, and tell my friend to open http://256.266.266.266:3000/ in his chrome browser.
But the answer is This site can’t be reached ERR_CONNECTION_TIMED_OUT. why? how do I connect to my nodejs application in my public ip?
I do not have any antivirus or firewall as far as I know.
Telnet telnet 256.266.266.266 3000 say .Could not open connection to the host, on port...
netstat -an | find "3000" say TCP 0.0.0.0:3000 0.0.0.0:0 LISTENING

How to access meteor app from outside without passing through NginX?

I am hosting a meteor app on an Ubunu Linux machine. The app is listening on port 3000. If I use a webserver, like NginX and forwards the HTTP requests from port 80 to 3000 I can browse to the server from the outside and see reach the app. However, when I try to access the app directly at port 3000, i.e. browse http://myhost:3000 it just tries to connect and nothing happens.
I have made sure that all firewalls are down and that the app is listening on all interfaces, i.e. 0.0.0.0:3000, so that is not the issue.
To verify that port was actually reachable, I created a simple node js webserver:
var http = require('http');
http.createServer(function (req, res) {
res.writeHead(200, {'Content-Type': 'text/html'});
res.write('Hello World!');
res.end();
}).listen(3000);
Now browsing to the the sever, I can see "Hello World!". So obviously this works so why I can not reach meteor has nothing to do with firewalls or unopened ports.
Thus it seems that there is something strange when trying to access a meteor app directly at port 3000. But why? I use the following environment variables:
export MONGO_URL=mongodb://localhost:27017/meteor
export HOST=myhost
export PORT=3000
export ROOT_URL=http://myhost
So what am I missing? Ports are open and I can see that the node process instance is listening on port 3000 when I run netstat -tulpan
I was using the force-ssl meteor package which makes a redirect back to the ROOT_URL without port number. So solution is to remove the package to make it work with a custom port.
I was discussing the solution on the meteor forum where I got the solution:
https://forums.meteor.com/t/can-not-access-meteor-app-without-passing-through-nginx-server/40739/11

Running a simple script on a web server using NodeJS

I'm trying to make a simple JS script run on my web server using NodeJS :
var http = require('http');
var server = http.createServer(function(req,res) {
res.writeHead(200,{"Content-Type":"text/plain"});
res.end("Hello World!");
});
server.listen(8000);
console.log('Server running');
Output when I run this on local :
curl http://127.0.0.1:8000
Hello World!
However, when I try to curl onto my web server it timeout.
I don't know if it's important or not but I have apache2 installed on the web server. Any help would be very much appreciated.
You can't access node.js from outside because it is listening on localhost IP i.e 127.0.0.1. You need to configure node.js to listen on 0.0.0.0 so it will be able to accept connections on all the IPs of your machine.
Try this:
server.listen(8000, "0.0.0.0");
If it still doesn't work and you are using iptables you may have to open port 8000. Try this:
iptables -I INPUT -p tcp --dport 8000 -j ACCEPT

Use a node app from another device locally

I have a server (10.0.0.12) and my laptop (10.0.0.2) on a local network.
When I run curl http://10.0.0.2:3000 on the server, it works fine. When I run curl http://10.0.0.12:3000 on my laptop, it doesn't work saying site is unavailable.
I am able to ping and ssh into the server from my laptop.
Here is my code to finish the connection:
app.set('port', (3000));
app.listen(app.get('port'), function(){
console.log("Node app running on localhost:" + app.get('port'));
}
I've tried passing in an ip address to the listen() function, but made no difference. I tried passing in 10.0.0.12 (the ip address of the server), 127.0.0.1, and 0.0.0.0 all with the same result.
How can I host my node app on a local network and have everyone who is on the local network be able to access it through the browser?
EDIT: I'm running on CentOS 7.
EDIT2: When I run netstat -lnt, it says this:
tcp 0 0 0.0.0.0:3000 0.0.0.0:* LISTEN
Have you tried to just omit the IP address? It should then be available on the IP address of the machine it is running on and the specified port.
As suggested by HA. remove the IP.
As you can see from the documentation:
https://nodejs.org/api/http.html#http_server_listen_port_hostname_backlog_callback
If the hostname is omitted, the server will accept connections directed to any IPv4 address (INADDR_ANY).
P.S. Which is the OS on the server?
Maybe you can try :
app.listen(3000, '0.0.0.0', function(){
console.log("Node app running on 0.0.0.0:3000");
}
A possible issue could be you aren't using the http module?
var http = require('http').Server(app);
http.listen(3000, function () {
console.log('App running on port 3000');
});
A good practice would be set the port like
app.set('port', (3000));
var http = require('http').Server(app);
http.listen(app.get('port'), function () {
console.log('App running on port ' + app.get('port'));
});

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