Remote access behind 2 routers

I’ve always had remote access (with duckdns-url) like a charm. But after installing some new hardware I’m not getting inside anymore…

Before I had just my modem/router from my provider, now I have my own router behind that one from my provider. So that’s what’s getting me stuck at this point.

So my modem/router from the ISP has an (internal) adress:
My own router is recognised by the ISP modem as:

My own router makes an network with Ip’s:

I’m not sure what to put in my portforwarding rules in both routers… Anyone can help me with this problem?

Edit for popular request :slight_smile:

If you want help then at least stop masking your internal IPs. Nobody cares and nobody can do anything with it.
My router is my HA is

See… it doesn’t matter.
Edit your post with real IPs and how it’s connected.
Sitting here guessing is not going to lead anywhere

Fixed this myself. Made an error in one of my configurations… Way too many night-shifts and not enough sleep I think :slight_smile:

If anyone has the same problem, it’s not that hard at all:

At your ISP-router make a Port Map rule like this:

Protocol: TCP
External port: The port your Duckdns is pointing to
Internal port: choose one…
Internal Host: the IP from your own modem

At your own router you make the Port Map rule like this:

Protocol: TCP
External port: the internal port of your ISP-modem/router
Internal port: 8123


Your ISP-router/modem IP (internal):
Your own routers IP:
Your HA-IP:
Your external link: http// (or https)

Your ISP-settings: External port: 4444 / Internal port: 6666/ Internal host
Your own router settings: External port: 6666 / Internal port: 8123 / Internal IP:

I would not advice using this setup.
It will be hard to maintain, especially with hubs.

I’d say use the normal way and make the second router a switch that way you have one network instead of two separate where you need to forward data in-between.

Yeah, I understand your concern.

My problem (and why I have my own router behind the modem) is that I have a lot of problems with my ISP-modem (and I’m not alone…), specially with static IP’s, giving IP’s to wrong devices, crashes when editing configuration… ISP can’t/won’t help and won’t let me use the device as a modem only.