Disable DHCP but enable custom DNS for cable and wireless connected devices?

I appreciate but the final conclusion is that if i set it to bridge i have no ipv6.
On normal mode i cant select DMZ or change DHCP settings there.

What i want is to use my router as an smart switch with hability to set up custom dns + connect via wifi to the same network, but i dont seem to find a solution, since i always have double nat then.

In terms of OPENWRT what can i do without messing with the isp modem?

There's pretty much nothing to do, if you can't change those settings you're stuck with double nat with no port forwarding capabilities.

Are you sure you can't even change DHCP settings? What ISP are you using and what's the model name of your modem?

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Yes its pretty bad.

Ziggo, Connectbox.

That's possible. I have a full dualstock connection from Ziggo with a Connectbox. Not using bridge mode due to loosing IPv6 connectivity.

In your connectbox, turn of the following features: IPv6 firewall and WiFi (both 2.4 and 5 ghz). IPv6 firewall must be disabled, it won't route traffic to OpenWRT when OpenWRT request its own prefix via IPv6 prefix delegation. OpenWRT should also be the only client on the Connectbox. With the IPv6 firewall disabled, IPv6 clients are directly exposed to the internet (the Connectbox configuration page won't be exposed). Create DHCP reservation for static OpenWRT address optionally. Put your OpenWRT router Don't turn of DHCP, otherwise DMZ won't work. Last, configure your OpenWRT router in the DMZ settings of the Connectbox. Now IPv4 and IPv6 traffic is routed to your OpenWRT router.

Make sure your OpenWRT router create its own network to serve wireless and wired clients, and connect the WAN port to your Connectbox.

Use scripts / DDNS to update IP addresses if you expose services to the web. Ziggo has long IPv4 lease times, I won't change for years. However, the IPv6 lease time is very short, so your prefixes could change after a router reboot.


I dont have the DMZ option available, i spoke with the ISP they changed everything to ipv4 and now i can see DMZ, now i can use it and set but then no ipv6.

Just to provide an alternative angle.
Using PREROUTING firewall rules, you can redirect all DNS requests (typically port 53) to a local DNS server instance like dnsmasq. Unless your devices use DNS over HTTPS or within their own tunnel, all requests will go to that instance.

There are threads with examples like here:

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It might not be the best solution but is probably the easiest: You could double-NAT. Connect the modem to the router's WAN port and let the router have its own subnet.


That's weird. Which Ziggo region are you in? It should be the other way around: putting the modem in bridge mode disables IPv6 and disables all router functionality (including DMZ).

Yes very! The moment they enabled all the options i lost ipv6...

UPC region.

Can you post the information page of your Connectbox?

I will look into it, this is very useful thank you.

Are you in DS-lite area? Such configuration would only be possible with full dual stack.

Yes i'm. I'm speaking with Ziggo.

Seems like if they bring the modem back to normal i have ipv6 but then no dmz option again. Very weird.

And if they enable DMZ then i have no ipv6.

Im pretty sure there's something wrong with your Connectbox configuration (not your fault). Did Ziggo confirm this is unexpected behaviour? Maybe do a factory reset? Ziggo is also able to reset and reconfigure your Connectbox remotly, maybe they can help you.

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I do also think so, makes no sense that i cant have dmz option with IPV6 enabled.

I'm still trying to speak with them.

Can you please post a picture of your menu where you can select DMZ ?

No problem, here you go. The DMZ option can be found at Advanced Settings > Security > DMZ (Geavanceerde instellingen > Beveiliging > DMZ).

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Yeah then something is wrong really, because it all is hidden, the only options i have are firewall and dhcp. i'm waiting them to fix it so i can move with the DMZ stuff.

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Spoke with them, they are going to return to ipv6, there is no other way, with ipv6 i have no option for DMZ, without ipv6 i have DMZ or bridge mode, really sucks.

Im out of options.