Sorry for the long question.
What it means is this: I am managing a small LAN that is protected by a router.
router 192.168.1.1 server 192.168.1.9 client 192.168.1.2 client 192.168.1.4
Since I have a static IP from my ISP, which is lets say 245.34.344.34, I can access my LAN at that address.
Now, I have set up my router's port forwarding config to this: when I SSH to 245.34.344.34 out from the internet, it forwards it to server 192.168.1.9:22. And when I FTP to 245.34.344.34, forwards it to client 192.168.1.2:21. Fine.
Then, when I am working from within the LAN, on my client 192.168.1.2 computer and that I want to access 192.168.1.9 through FTP, the router tries to forward it back to 192.168.1.2. But I am not sure what is happening.
On server 192.168.1.9 (which runs ubuntu 14.04.3 LTS (GNU/Linux 3.19.0-47-generic i686), when I
sudo ufw status:
To Action From -- ------ ---- 80 ALLOW Anywhere 443 ALLOW Anywhere 22 ALLOW Anywhere 3000 ALLOW Anywhere 21/tcp ALLOW Anywhere 21 ALLOW Anywhere 80 (v6) ALLOW Anywhere (v6) 443 (v6) ALLOW Anywhere (v6) 22 (v6) ALLOW Anywhere (v6) 3000 (v6) ALLOW Anywhere (v6) 21/tcp (v6) ALLOW Anywhere (v6) 21 (v6) ALLOW Anywhere (v6)
But if I do
PORT STATE SERVICE 22/tcp open ssh 80/tcp open http 631/tcp open ipp 3306/tcp open mysql
Now on client 192.168.1.2,
PORT STATE SERVICE 21/tcp closed ftp 22/tcp open ssh 80/tcp open http 443/tcp closed https 3000/tcp closed ppp
It shows that the server's port 21 is closed.
I don't get it. Must be something obvious...
Can someone please help me understand how to reach my server through FTP from within the LAN?