🛠 Pi-hole : bloqueur de pub DNS sur Zero W

Objectives

Transform the Zero W into a Pi-hole filtering DNS server: 512 MB is more than enough, and Wi-Fi eliminates the Ethernet dongle required by the Zero without radio.

Hardware

• 1 Raspberry Pi Zero W connected to Wi-Fi (connection tutorial) and up to date
• Static IP address of the board on the LAN

Steps

1. Install the official installer: curl -sSL https://install.pi-hole.net | bash (read the prompts: the resolution interface will listen on wlan0).
2. Set the address: static DHCP lease on the router, otherwise the DNS will follow a ghost IP.
3. Point clients to the board: either via DHCP option 6 on the router, or manually (DNS = Zero W's IP) on a test device.
4. Monitor activity: pihole -c in the terminal displays blocked/allowed queries live; the web interface is at http://<ip>/admin.

free -m          # le démon pihole-FTL reste sous ~100 Mo
pihole -g        # met à jour les listes de blocage

Verification

nslookup doubleclick.net 127.0.0.1 returns the Zero W's IP (0.0.0.0 depending on configuration): filtering is working.

Common Errors

• Forgetting to update the DNS on the client side: nothing passes through Pi-hole.
• Not monitoring RAM: with 512 MB shared between CPU/GPU, avoid adding a heavy web server alongside it.
• Congested Wi-Fi: perceived latency comes from the radio link, not from Pi-hole.