I have two machines running docker. A (powerful) and B (tiny vps).
All my services are hosted at home on machine A. All dns records point to A. I want to point them to B and implement split horizon dns in my local network to still directly access A. Ideally A is no longer reachable from outside without going over B.
How can I forward requests on machine B to A over a tunnel like wireguard without loosing the source ip addresses?
I tried to get this working by creating two wireguard containers. I think I only need iptable rules on the WG container A but I am not sure. I am a bit confused about the iptable rules needed to get wireguard to properly forward the request through the tunnel.
What are your solutions for such a setup? Is there a better way to do this? I would also be glad for some keywords/existing solutions.
Additional info:
- Ideally I would like to not leave docker.
- Split horizon dns is no problem.
- I have a static ipv6 and ipv4 on both machines.
- I also have spare ipv6 subnets that I can use for intermediate routing.
- I would like to avoid cloudflare.
Can you elaborate on the IP would not be unique part?
If you can fool the Internet that traffic coming from the VPS has the source IP of your home machine what stops you from assuming another IP to bypass an IP whitelist?
Also if you expect return communication, that would go to your VPS which has faked the IP of your home machine. That technique would be very powerful to create man in the middle attacks, i.e. intercepting traffic intended for someone else and manipulating it without leaving a trace.
IP, by virtue of how the protocol works, needs to be a unique identifier for a machine. There are techniques, like CGNAT, that allows multiple machines to share an IP, but really it works (in simplified terms) like a proxy and thus breaks the direct connection and limits you to specific ports. It’s also added on top of the IP protocol and requires specific things and either way it’s the endpoint, in your case the VPS, which will be the presenting IP.