Cannot access HA UI at all after duckDNS/lets Encrypt attempt - BT Smart Hub

I was following Will Surridge’s video Home Assistant - Back To Basics 4: Duck DNS on setting up DuckDns and Lets Encrypt. I had the domain from some time ago but had not set it up fully.

I installed Lets Encrypt ok and DuckDNS in HA seems to be fine, as regards the logs.

However, I now cannot open the url at all, whether using the homeassistant or ip address method.

My belief is I have done something wrong on the port forwarding step. The issue with these kind of steps in instructions is that rarely do they have the same router setup/front end and so, unless you have in depth knowledge of firewalls/port forwarding, it is difficult to relate to your own router. I have a BT smart hub. I can show what I have done which is set up the basic rules (I think…). However, I couldn’t find the Inbound Services equivalent (6:10 in the video) so think that may be the issue. Should have backed out at that point but i soldiered on.

What I have set up is below. I can access the HA logs via SSH and it looks like HA is starting.

I will supply anything that could be useful but not sure what I should be looking for so will need guidance on such.

https://domain:8123/

Although that did not seem to work initially, I retried it after your reply. It did work using the external domain on this attempt, so I do have access now. Should the local address still work I.e. homeassistant.local:8123 or the other variations without local or with ip address, as these seem to be inaccessible now.

I believe if you are not going to forward your domain to port 8123 and if you have public IP then its a wrong setup.

  1. You need to direct open port to your proxy server IP
  2. You need to forward both port 80 and 443 just because you will require SSL for security
  3. port 8123 should only be made available for local access. Unless your ISP block port 80/443

so this setup will give you access to HA using https://yourdomain.com or http://yourlocalip:8123

or better yet used nabucasa

If he does not have a proxy server, there is no need to forward 443, direct forwarding 8123 to 8123 works fine too.

yes… I agree… like I said… if you are not going to forward your domain to 8123

I realise that this all makes sense to you but I am struggling with understanding what I need to do. I actually believe I had NabuCasa set up when I first started dabbling with home Assistant last year. However, it seemed from posts that I needed to encrypt myself and that is why I followed the video.

Given my lack of real understanding of firewall ports and encryption, is it best that I attempt to uninstall LetsEncrypt and get DuckDNS/NabuCasa working together again (although I will have to look that up too)?

Oh and just to help with your questions regarding my setup:

Raspberry Pi4 Home Assistant installation, not a docker setup
BT Smart Hub 2 basic connection (no special servers involved)

NabuCasa or Nginx Proxy Manager