@Ollie_ 

Hi,

Don't trust those online portcheckers too much. I have seen them reporting ports as "closed" while external access to the service running on that port worked just fine.

First verify that you can access the service on port 22 (normally SSH) of client 192.168.0.69 from another device within the same network.

If that works fine, then verify there is no firewall on the Ubuntu Server blocking access from external IP addresses.

Also, I recommend you don't add extra zeros in front of numbers when you enter IP addresses (like 069). It may work fine on the Archer C6, but in general this is like asking for trouble.

  @woozle 

Thanks for the response!

• I can connect fine to the server from devices on the internal network
• There is no firewall setup; the output of ``sudo ufw status`` is ``Status: inactive``
• I think this is more a problem with the router or the ISP as even traceroute isn't working on the router's external address; when I run traceroute <<external IP>>, it hangs after about 7 hops.

  @Ollie_ 

To rule out some parts of the chain from the Internet to your Ubuntu Server maybe try if you can at least get as far as the C6 itself.

Either setup a VPN Server on the C6 and then connect to it via a VPN client device from the Internet or enable "Remote Management" (can be enabled under "Advanced" -> "Administration") and then connect to the C6's webGUI from another device on the Internet via a web browser.

If even that doesn't work, then it would indeed point to a problem with the ISP.