Remote access behind NAT (tunnel, tunnelbroker, 6in4, VPN, port knocking)

I would like to get access to my network from the outside world.

My router is behind NAT and I don’t have a public IP nor access to the router configuration.
How can I get access to my router? Is it possible via tunnelbroker from hurrican electric or do the require my IPv4?

I would rather use a free option than a paid service like a vpn provider.
I use a synology NAS which can be connected via the synology tunnel “quickconnect.to”.
maybe that is an option?

Assuming you also do not have a public IPv6 address on your router which is accessible from outside then you need to start your connection from inside and use a Man in the Middle there are certainly free options although you are using commercial third parties which will try to pull you into a paid tier, but I have a free oracle VPS and also setup Netbird which are still free for limited non commercial use. But there are a lot of other possibilities

This can be a VPN provider which supports port forwarding (e.g. ProtonVPN), or you can rent a Virtual Private Server ( I have an Oracle VPS which can be had for free, see at the bottom of this guide), or use things like Netbird, Zerotier, Cloudflared, Tailscale or ngrok and there are more, I have setup Netbird on several OpenWRT and Windows and Linux clients and it works well, see my notes about setting up Netbird on OpenWRT and the Netbird support thread.

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TunnelBroker doesn't work without a Public IP.

Tailscale. All your clients connect to a server on the internet and the connections between the clients are secured with wireguard. It's like having a private network with all members connected via tailscale. You can a set up your router to allow access to all your devices on its network without having to install tailscale on every one.
In my experience it works perfectly fine even in double nat (router behind router) scenarios.

You need an account but it's free to use for non commercial use. Setup is relatively strait forward I got 2 routers sharing their local networks over tailscale setup quickly using chatgtp.

thank you, this is very helpful.

I am not a network specialist but I would probaby be able to follow your great instructions.
Below some bullet points of what I am trying to achieve.

Would you suggest oracle vps, netbird or tailscale?

  • use personal domain to access services behind NAT without public IP
  • use port knocking
  • access NAS
  • access home automation services
  • access self-hosted website through personal domain name
  • connect to the internet via P2P to my home router which runs a firewall and adware

are these options encrypted P2P?

You can open listning ports with upnp or natpmp clients, like tailscale etc do.
What NAT you have https://natchecker.com/ ?
the "open" and "cone" types more or less map you 1:1 to public IP and you may not even need that.

All those should do the trick (more or less).

When using an oracle VPS you have more freedom to setup things as that will givevyou a public ip address you can use to your liking but of course it is more work then using e.g. tailscale or netbird.
Those are more or less doing the same they give access to your home but cannot provide a public ip address which you can use to accessing a webserver but for this you can use e.g. cloudflared.
With an Oracle vps you can do it all yourself but as said you have to do it all yourself.
Netbird and Tailscalei are a simple and fast way to access your home.

NAT3: Port Restricted Cone NAT

cloudflared, I need to investigate that.

So for pointing my registered domain at my webserver and NAS this only works with oracle I guess?

I will have to investigate these options like Netbird and Tailscale and see what is possible.

That means you can get connections back on the source port of existing connection, i.e you do not need upnp natpmp for UDP-only torrent, not much else works back, some voip may sneak through but better get the port forward via nat traversal protocols.

Yes but cloudflared will also do the trick.

But you do not get seamless access to your home for that you need e.g. netbird or tailscale.

With a VPS you can do it all but as said you need to set it up all yourself