Written 25 Aug 2026. This is a how-to, not a product card. Buy links are not tagged yet.

Point the house at the leftover-box ad block

After Pi-hole is installed, tell the house router to ask the leftover box for names. Phones and laptops need no app. Sites still load. A lot of ads do not.

DNS is the phone book that turns site names into numbers. Your phones and laptops ask something for that lookup every time they open a page. Tonight that something becomes the leftover box. You change one router setting. No app on every device.

Skip until Pi-hole is up

If the admin page from the first useful thing on the leftover box does not open yet, stop. Install Pi-hole first. This note only points the house at a box that already answers names.

A DHCP reservation is strongly recommended first. The house will keep looking for the leftover box at the same address after a reboot. If that number moves, ads come back and this DNS change looks broken.

What you are changing

Only the router DNS setting. You are not buying a new router. You are not forwarding ports. You are not opening Pi-hole to the internet. The leftover box stays on the house network and answers name lookups for the house.

Find the DNS settings

Open a browser on your normal computer. Log into the house router with the address on the sticker, often 192.168.1.1 or 192.168.0.1. Same login as find the leftover box on the house network. That password is on the sticker, or the one you set.

Look for Internet, WAN, DHCP, or LAN DNS. Wording varies by maker. Primary DNS is the leftover box address, the same number you use for SSH and the Pi-hole admin page. Secondary: leave blank for a first pass so devices keep using Pi-hole. A public resolver as secondary is fine only if you understand that when the leftover box is down, phones can bypass Pi-hole and ads return. Blank is the honest first choice.

Save. Some routers want a short wait, or a reboot of the router, before phones pick up the new book.

Safer first test

If you are nervous, set DNS on one laptop or phone only, not on the router yet. Confirm ads drop on that one device. Then set the whole house on the router. Same leftover-box address either way.

Check

Browse a few sites you know used to show ads. Sites should still load. A lot of the banners should not. Open the Pi-hole query log on the admin page if you want to see the house asking the leftover box. If ads came back overnight, start with is the leftover box still on? before you touch the router again.

Undo

Set DNS back to automatic, or back to your ISP. The internet still works without Pi-hole. You did not brick anything.

What next

Leave it a week. Then maybe a file share on this same box. If the leftover is still on house Wi-Fi, put it on a cable: a cable beats Wi-Fi for the leftover box. Skip a mesh kit for this. Waiting is fine.

Skip

• Skip a new mesh kit for ad block.
• Skip buying a Raspberry Pi “because Pi-hole.”
• Skip Unbound on day one.
• Skip per-device ad apps when router DNS already works.
• Skip opening Pi-hole to the internet.