Very different solutions.

• DuckDNS: you expose your HA to the internet like a public website and register it’s address with DuckDNS so you can look it up.
• Wireguard: you VPN to inside your firewall and can access anything on your private network.

Wireguard all the way. Exposing just a VPN endpoint that can’t be connected to without the right cryptographic keys is a much more secure and maintainable attack surface.

BTW I assume that’s what you meant by “DuckDNS”. Using that service is orthogonal to making HA visible externally, but is (I think) the common pairing.

• Slurm cluster
• MPI development

This is my number one. I hate having everything in one subscription list, battling each other for my attention. My local communities can’t stand up to lemmyworld or beehaw communities in my sub list, and “local” puts all local communities in, most of which don’t interest me.

That’s just one example though, and it’s not all about instances. News about energy policy can’t battle with world politics, so keeping the two in separate lists is important to me even though they are both remote sets of communities for me.

I was rather peeved I had to give an email to create an account on Lemmy. It shouldn’t be needed.