Cannot acces my domain

[Rainbowgeorge]

Hello everyone,

i'm quite new to Linux in general.

I am trying to set up OwnCloud on my Raspberry Pi 3B+ and i'm pretty much following this guide:
https://www.youtube.com/watch?v=H1tm4-BWNrU
so ive been trying to use nginx and got a domain aswell

Now i am at the point where i can see the nginx welcome page over my local network,
but when i acces my domain i either get error 503 from nginx or my browser says that the server is too slow.
Systemctl status ddclient says its updating, but doesn't tell me an IP-adress in the end

Maybe my ddclient.conf is set up wrong but when i go to my domain provider, it seems like it gets the right IP-adress.
Opening all ports on my router for testing doesnt help aswell.
When i run certbot,it tells me : challange failed for domain

I hope this is in the correct subforum.

Thank you for your help.

EDIT: I think its my ISP, they may not allow opening port 80 IPv4
EDIT2: I was right about my ISP, they gave me acces and now i can see the nginx welcome page

[DanSman]

Because you are new to Linux.

Be careful when hosting your server from your home network. You need to secure your server as much as possible. It's really important! It will not take long and you will see some attacks on your server.

Keep this in mind.

We started a project for the ARM architecture last year - PwOSS - Privacy with Open Source Software. Might be interesting for you. It is based on Arch Linux ARM / Raspberry Pi.

You can install some software, especially a VPN connection. It's a great way to host your own server and reach it only with VPN.
You can follow an installation process available at GitHub
The scratch file is for the first launch of Arch Linux ARM. The other file is for our Raspberry image. We have not yet included the image in GitHub, so I would recommend using the scratch file if you would like to try it out.

However, read a little more before hosting your server from home.

Good luck,
Dan

[Rainbowgeorge]

Thanks for your awnser, i'll definatley look into that!

[RonnyReporter]

The easiest way to make sure your server is secure is by using a default deny firewall. This will block everything unless you open up the port yourself. On a webserver this means you can get away with only opening ports 80/443 and some random port for SSH access. This should protect against pretty much any remote exploits on services running on the server other than nginx/sshd.

To further protect you can set up a rate limiting firewall rule on the ssh port (see Arch wiki) and you can compile a kernel with some memory randomisation and other hardening options enabled. In case there is a remote exploit for say nginx the chances of anyone finding the right offsets to exploit the security flaw are greatly reduced.