boostchicken/nextdns-udm repository overview

⁠Run NextDNS on your UDM

⁠Features

1. Run NextDNS on your UDM with a completely isolated network stack. This will not port conflict or be influenced by any changes on by Ubiquiti.
2. Resolves IP addresses handed out by DHCP on the UDM!
3. Persists through reboots and firmware updates.
4. If you are already using PiHole and want to test NextDNS out, you can just stop your PiHole container and start this one in its place using the same IP/CNI config.

⁠Requirements

1. You have already setup the on boot script described here⁠
2. NextDNS persists through firmware updates. The on-boot script does not. If you update your FM setup on-boot again and everything should work.

⁠Customization

• Feel free to change 20-dns.conflist⁠ to change the IP address of the container. Make sure to update all ip references and the iptables rules in on_boot.sh⁠. The IP address can be anywhere from x.x.x.3 to x.x.x.254. .1 is reserved for the gateway and .2 is reserved for the macvlan bridge.
• If you don't want to use vlan5, just replace br5 with br(vlanid) in on_boot.sh⁠ and 20-dns.conflist⁠, also update all the ips accordingly
• The NextDNS docker image is not supported by NextDNS. It is built out of this repo. If you make any enhancements please contribute back via a Pull Request.
• If you want to inject custom DNS names into NextDNS use --add-host docker commands. The /etc/resolv.conf and /etc/hosts is generated from that and --dns.

⁠Docker

The offical repo is boostchicken/nextdns-udm. Latest will always refer to the latest builds, there are also tags for each NextDNS release (e.g. 1.6.4).

The Dockerfile is included, you can build it locally on your UDM if you don't want to pull from Docker Hub or make customizations

podman build . -t nextdns-udm:latest"

Building from another device is possible. You must have buildx⁠ installed to do cross platform builds. This is useful if you want to mirror to a private repo

docker buildx build --platform linux/arm64 -t nextdns-udm:latest .

⁠Steps

If you have already installed PiHole, skip right to step 6.

1. On your controller, make a Corporate network with no DHCP server and give it a vlan. For this example we are using vlan 5.
2. Install the CNI plugins with by executing install-cni-plugins.sh⁠ on your UDM
3. Copy 20-dns.conflist⁠ to /mnt/data/podman/cni (or a place of your choosing and update on_boot.sh⁠ symlink). This will create your podman macvlan network
4. Update your on_boot.sh to include the commands in on_boot.sh⁠. You can leave out the iptables rules if you don't want to DNAT all DNS calls to your PiHole
5. Execute on_boot.sh
6. Make /mnt/data/nextdns and copy nextdns.conf⁠ to it.
7. Run the NextDNS docker container. Mounting dbus and running in privileged is only required for mDNS. Also, please change the --dns arguments to whatever was provided by NextDNS.

 podman run -d --privileged --network dns \
    --name nextdns \
    -v "/mnt/data/nextdns/:/etc/nextdns/" \
    -v /var/run/dbus/system_bus_socket:/var/run/dbus/system_bus_socket \
    --mount type=bind,source=/config/dnsmasq.lease,target=/tmp/dnsmasq.leases \
    --dns=45.90.28.163 --dns=45.90.30.163 \
    --hostname nextdns \
    boostchicken/nextdns-udm:latest

Note: 8. Update your DNS Servers to 10.0.5.3 (or your custom ip) in all your DHCP configs.