DNS

Using a Pi-hole with UniFi

Fahim

• 3 min read
Share
Using a Pi-hole with UniFi
Photo by The New York Public Library / Unsplash

Following up from my previous post, let's assume you want to dive in and try it out. Well, here's how.

Introduction

Setting up Pi-hole to work seamlessly with your UniFi network is a great move. The absolute best way to do this is at the DHCP level.

By giving your Pi-hole's IP address to your devices via DHCP, the devices will talk directly to the Pi-hole for DNS requests. This keeps things fast and ensures your Pi-hole dashboard can actually see which specific device (e.g., "Dad's iPhone" vs. "Living Room Apple TV") is making which request.

Here is how to get it configured:

Step -1: Hardware & Installing Pi-hole

I'm assuming you have this already setup! Maybe a bit beyond the scope of what I was planning to cover here, but what I ended up doing was getting one of those cheap Dell Wyze 5070 thin-clients, installing an LTS ubuntu server instance, and installing Pi-hole on the bare metal device.

Pi-hole provides a highly reliable curl script that downloads and launches the installer.

  1. In your terminal, paste the following command and hit Enter: curl -sSL https://install.pi-hole.net | bash
  2. The script will download the necessary dependencies and then launch a blue-and-red text-based wizard in your terminal.

Step 0: Ensure Pi-hole has a Static IP

Before touching UniFi, make sure the device running your Pi-hole (whether it's a Raspberry Pi, a NAS, or a Proxmox container) has a static, unchanging IP address. If its IP changes, your entire network will lose internet access.

  • Example IP: Let's assume your Pi-hole is at 192.168.1.53.

Step 1: Point UniFi DHCP to your Pi-hole

You need to tell your UniFi gateway to hand out the Pi-hole's IP address whenever a device connects to the network.

  1. Log in to your UniFi Network Application
  2. Navigate to Settings (the gear icon) > Networks.
  3. Click on your primary network (usually named "Default" or "LAN").
  4. Scroll down to the DHCP section. Note: Depending on your UniFi version, you may need to change "Advanced Configuration" from Auto to Manual to see these settings.
  5. Find the DHCP DNS Server setting.
  6. Uncheck "Auto" and enter your Pi-hole's static IP address (192.168.1.53) in the DNS Server 1 field. Leave DNS Server 2 blank, or add a secondary Pi-hole if you have one. Do not put an external DNS like 8.8.8.8 as a secondary, or devices will bypass your Pi-hole.
  7. Click Apply Changes.
  8. (Optional) Repeat this process for any other VLANs (like IoT or Kids networks) that you want filtered.

Step 2: Enable Conditional Forwarding in Pi-hole

Right now, Pi-hole handles the DNS, but it doesn't know the friendly hostnames of your devices (it just sees their IP addresses). Conditional Forwarding tells Pi-hole to ask the UniFi Gateway for those friendly names.

  1. Log in to your Pi-hole Admin Interface.
  2. Go to Settings > DNS tab.
  3. Scroll all the way down to Advanced DNS settings.
  4. Check the box for Use Conditional Forwarding.
  5. Fill in the three fields:
    • Local network in CIDR notation: Usually 192.168.1.0/24 (adjust if your subnet is different).
    • IP address of your DHCP server (router): Your UniFi Gateway IP (usually 192.168.1.1).
    • Local domain name: Usually localdomain unless you changed it in UniFi.
  6. Click Save at the bottom.

Step 3: Refresh Your Devices

The new DNS settings won't apply to your devices until they renew their DHCP leases.

  • For phones and laptops, simply turning Wi-Fi off and back on is enough.
  • For hardwired devices like TVs or consoles, a quick restart will pull the new DNS info.

Once your devices reconnect, you should immediately see traffic populating on your Pi-hole dashboard with proper client names.