I would like to know if I can transfer the home Assistant that I have installed on my Raspberry, to a virtual VPS server ?, so that I no longer depend on my Rasberry but on an external server
Technically yes, but then you will depend on a cloud service and a functioning internet connection instead. If you have local IP devices you would like to control from HA, like wifi bulbs or switches or cameras, then you will have to expose them all to the internet so that the VPS can access them. And that is a huge security risk. This could be somehow mitigated if you have the VPS VPN into your LAN though.
And if you use non-routed networks like Zigbee or ZWave, then you will need a local hub/sbc/nuc anyway to bridge them, which you would also have to expose to the internet. Not a great idea.
Short answer: don’t do it, it’s probably not worth the trouble.
You can use a VPS for other things, like reverse tunneling into your home HA without exposing it entirely or to bridge two independent HA installations, like a vacation home, RV, boat, etc, to your home install.
ok thank you very much for your clarification
I do want to control a house in the middle of nowhere, the internet is supplied via 4g and therefore is under cgnat. In short, i do not have a public IP.
What about a reverse conection via vps?
If the devices connect to vps and my smartphone does it to…. This setup might work, isn’t it?
Yes, that works. My home internet is by 4g too. I use a reverse ssh tunnel over a VPS with a static IP to access my instance from the outside.
Could I know how you configured it? I’m in the same situation…
Very honestly, and don’t take this wrong, but if you don’t know how to do this you shouldn’t do this. Setting this up the wrong way (and the naive simple and easy setup is the wrong way) will create a lot of security issues and can fully expose your HA instance without you realizing it. And every setup is going to be different, depending on the VPS used, firewall used, your IP range, etc, so there is no one fits all tutorial.
Good alternatives are a VPN (Wireguard, OpenVPN, Tailscale, etc) or using a preconfigured reverse tunnel with Web Application Firewall, like Cloudflare Zero Trust. There are lots of tutorials settings these up with Home Assistant. I recommend looking into these options.
A quick Google search turned up this tutorial, which looks good from a quick skim.