setup-ipsec-vpn VS wireguard-install

I can't connect to VPN. I have run VPN on this Raspberry Pi via IPsec. All of a sudden it stopped working. I tried installing IPsec on another Raspberry Pi, with no success, the same problem. I can't connect.

I have set up a vpn server using this, https://github.com/hwdsl2/setup-ipsec-vpn. I am able to log into the server and shut it down if I chose.

ok so here is the deal... I am currently running this script on a rpi at home that also runs a pihole... I do this for 24/7 ad blocking on my phone and to get around blocks on public wifi...

First, go here and use this setup https://github.com/hwdsl2/setup-ipsec-vpn . I put this on a raspberry pi and it works great, but you can put this on an old laptop or really anything.

you can run your own vpn node on some cheap vps server using algo (https://github.com/trailofbits/algo) or this: https://github.com/hwdsl2/setup-ipsec-vpn

after that u can simply run this script https://github.com/Nyr/wireguard-install that helps you automatically install wireguard and create a config ( to add more configs just run it again ). This script also generates QR code that you can simply scan by ur phone

I currently have WG set up on a Linode Ubuntu server (installed from https://github.com/Nyr/wireguard-install) with Pihole setup in the background. I have everything working just fine, except for some websites showing as "Page cannot be displayed". I've looked up in the subreddit and some have recommended changing the MTU (which I've tried on server/client), but that doesn't resolve the issue. In Pihole, it shows that it responds correctly. I did enable IPv6, but this happened before adding IPv6. Running curl from SSH to access the affected site, it tells me 301 Site moved permanently. Here's the server config:

https://github.com/Nyr/wireguard-install

As for the VPN: I always use this installer on a raspy pi (you can do this on a virtual machine): https://github.com/Nyr/wireguard-install But that is only because I hate having to set up keys.

So I got a Libre AML-S905X-CC (Le Potato) to play around with but all the ideas I see online are about emulating games, running a nas, running ad blocker, vpn server, 3d printer, website hosting. All these just seem like these would be better to run on an actual server or the ideas are lame, basic, and overused. I just want some useful things that only these single board computers can do to justify their purpose. I like stuff like the PiKVM or wireless usb like VirtualHere. The Arduino has their spot for robotics and what not, but what do SBC have to offer besides being small and broad purpose? Stuff like can I make it auto start my car in the morning, attached it to a pcie port on my pc, make a cellular wifi hotspot modem thing, make a smart tv, make a robot with AI, bypass wifi router settings, make a smart door deadbolt or smart window blinds, AI caht bots, transmit landline calls to the internet, drones with facial recognition, spy balloons, kiss under the bicycle racks in walmart, watch the rat movie that cooks food, ratatoot toot, overthrow the government? Those types of ideas are stuff I see as useful but also I want to look up later if those are something that exists already.