Port 3003 is not working while ports 3000 - 3002 are working fine

ush189

12/11/23, 7:35 PM

I have several node.js apps on an Ubuntu server working just fine on ports 3000 - 3002. Now I added one more app to port 3003 and it is not working anymore. I switched the apps on port 3002 and 3003 and it's still port 3003 not working, so it's not the app itself causing it.

Also when I do the request from the Ubuntu server itself it is working:

$ curl http://<my-domain>:3003/
Hello World!

But from outside or from the browser I'm getting a timeout:

$ curl http://<my-domain>:3003/
curl: (28) Failed to connect to <my-domain> port 3003 after 21091 ms: Timed out

There is nothing in the iptables...

$ sudo iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

... and the UFW is inactive:

$ sudo ufw status verbose
Status: inactive

Here the netstat output:

$ netstat -tulpn
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
[...]
tcp6       0      0 :::3000                 :::*                    LISTEN      28483/node /home/we
tcp6       0      0 :::3001                 :::*                    LISTEN      28489/node /home/we
tcp6       0      0 :::3002                 :::*                    LISTEN      28531/node /home/we
tcp6       0      0 :::3003                 :::*                    LISTEN      28503/node /home/we
[...]

What else could it be?

279

0 + 2

server

iptables

firewall

networking

Doug Smythies

12/11/23, 7:51 PM

What do you mean by "from outside"? If it means a different network or the WAN, how is port forwarding done? And was port 3033 added?

ush189

12/11/23, 10:41 PM

Your comment got me googling again and it turned out that I needed to also add the port in the firewall settings of my server provider.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Port 3003 is not working while ports 3000 - 3002 are working fine

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