Making adblock use IPv6

SecretRookie · June 24, 2025, 5:44am

Hello. I installed adblock according to the support thread and it only partially works.

I think it is because my devices use two DNS servers. One is IPv4 and the other IPv6. So how can I change things in openwrt so that the IPv6 DNS is covered as well? I would manually configure the devices, but my less tech savvy family also uses the network and I think it would take longer to set up, plus I'm afraid it might break the devices on other networks.

I should also mentioned that I use odhcpd and unbound for DHCP/DNS (according to this wiki article). I do not yet know how to reinstall/reinstate DNSMASQ, so if that could solve my problems do please mention how I can reinstall it without breaking my network.

egc · June 24, 2025, 7:06am

Adblock should be able to work with unbound see:

github.com/openwrt/packages

net/adblock/files/README.md

master

<!-- markdownlint-disable -->

# DNS based ad/abuse domain blocking

<a id="description"></a>
## Description
A lot of people already use adblocker plugins within their desktop browsers, but what if you are using your (smart) phone, tablet, watch or any other (wlan) gadget!? Getting rid of annoying ads, trackers and other abuse sites (like facebook) is simple: block them with your router. When the DNS server on your router receives DNS requests, you will sort out queries that ask for the resource records of ad servers and return a simple 'NXDOMAIN'. This is nothing but **N**on-e**X**istent Internet or Intranet domain name, if domain name is unable to resolved using the DNS server, a condition called the 'NXDOMAIN' occurred.

<a id="main-features"></a>
## Main Features
* Support of the following fully pre-configured domain blocklist feeds (free for private usage, for commercial use please check their individual licenses)

| Feed                | Enabled | Size | Focus            | Information                                                                       |
| :------------------ | :-----: | :--- | :--------------- | :-------------------------------------------------------------------------------- |
| 1Hosts              |         | VAR  | compilation      | [Link](https://github.com/badmojr/1Hosts)                                         |
| adaway              |         | S    | mobile           | [Link](https://github.com/AdAway/adaway.github.io)                                |
| adguard             |    x    | L    | general          | [Link](https://adguard.com)                                                       |
| adguard_tracking    |    x    | L    | tracking         | [Link](https://github.com/AdguardTeam/cname-trackers)                             |
| android_tracking    |         | S    | tracking         | [Link](https://github.com/Perflyst/PiHoleBlocklist)                               |
| andryou             |         | L    | compilation      | [Link](https://gitlab.com/andryou/block/-/blob/master/readme.md)                  |

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Did you set it up using unbound as backend?

It is blocking by DNS so it does not matter if it is IPv4 or IPv6

SecretRookie · June 24, 2025, 7:34am

I have selected unbound as the backend, but it still lets some ads through.

Looking into it a little more I only set wan as a Startup Trigger Interface, which might be the actual reason they are getting through.

I have a PPPoE setup, with a wan interface, a wan_6 interface, which is a Virtual dynamic interface (DHCPv6 client) and can't be edited and a wan6 interface that is an alias of the wan_6 interface. Which of these should I add as a Startup Trigger Interface to ensure full coverage of my network.

egc · June 24, 2025, 7:46am

Not all ads are blocked, these solutions only block by DNS address and even that is not blocking 100%.
In-page ads need e.g. a browser extension or proxy to block and youtube ads are even more difficult to block.

I am not sure but if adblock has started (you can see it on the adblock Lici page) then it is fine.

dibdot · June 24, 2025, 7:50am

Nope it's unrelated. Adblock only generates a blocklist for the selected DNS backend - IPv4 or IPv6 does not matter here. Unbound is supported and works quite well (I use it for development as well ).
Bottomline check your unbound settings and make sure, that connected clients always use your local unbound instance for resolving IPv4 and IPv6.

SecretRookie · June 24, 2025, 8:00am

I am aware of the limitations of DNS ad blocking. The types of ads I am seeing now and likely shouldn't are ones that were blocked when I was running AdGuard Home on my Raspberry Pi 4. Particularly in some mobile apps.

It has started, but I'll still add the other interfaces, just to check.

egc · June 24, 2025, 8:12am

Just like already noted make sure your LAN clients are using unbound and not their own private DNS server.

And of course you can look into the block lists you have chosen, depending on your router/memory you can add more extensive block lists