Smart home devices are effortless to operate: plug them in, connect to Wi-Fi, and forget about them. They work in the background without any noise; the convenience becomes invisible, and so does their activity in the home network. We know that the devices are connected to the network, but we are not aware of what they are doing.

That was me until I installed Pi-hole. I installed it for a completely different reason. I installed it on my Debian server for the sole purpose of implementing network-wide ad blocking. The goal was to see fewer and cleaner ads across every device in my home connected to the local network.

Along with a clean browsing and streaming experience, I have visibility. I observed many requests from devices that weren’t actively being used at that moment. Many smart devices, like smart speakers and smart TV boxes, communicate with the internet even when they are idle. There were regular check-ins, analytics domains, and telemetry endpoints. They didn’t look malicious, but they were there.

The house was quiet, but the network was not.

I didn’t install Pi-hole for surveillance

Ad blocking was the goal — visibility was the surprise

I run a simple and organized home lab. It is powered by a mid-range Debian server running on an old, repurposed laptop. The storage needs are handled by my dated Synology NAS. The server and NAS are used to consume media via Jellyfin, file services via Nextcloud, and photo libraries via Immich. My whole family uses these services in different ways.

Since I had a dedicated server, I decided to install Pi-hole for network-wide ad blocking. It was for a clean browsing experience. Pi-hole was simple to implement and easy to operate. It was lightweight, and its DNS filtering worked efficiently.

Its DNS filtering works in a simple way: any device on my network tries to resolve a domain, and Pi-hole filters the DNS query before any actual connection is established. If it is clean, it allows the request; otherwise; it rejects it. It was a centralized solution for all devices on my network. No hassle of implementing per-device blockers. A perfect solution that can be implemented once and forgotten about.

This was all good and exactly as I expected until I opened the Pi-hole admin panel after a couple of hours of runtime to check whether everything was running properly. The homepage/dashboard itself had a ton of data. Total queries, blocked queries, client activity, query types, blocked domains, and much more. And then there was a dedicated section for all real-time queries. All the queries were logged there. What I assumed would be occasional queries turned out to be constant.

My smart devices never really sit idle

The DNS logs told a different story

I have a number of smart devices in my home. I use an Alexa Echo smart speaker, a Wipro smart bulb, and a Fire TV Stick 4K. My mother uses an Airtel Xstream TV box on her smart TV. Previously, I had no idea what these smart devices were doing in the background.

When the Pi-hole dashboard started populating with real-time queries, I noticed the same device IP appearing repeatedly even when we were not using them. For example, with the Alexa Echo, I observed periodic check-ins, multiple DNS requests within the same second, and calls to cloud services. For my mother’s smart TV box, there were background calls to analytics services, CDN lookups, ad-related domain lookups, and time synchronizations. This was when the TV screen was off and there was no active playback.

One interesting thing was that there was no constant flooding of queries, but rather rhythmic bursts. They happened every few minutes in small clusters, and the log was never fully silent. It felt like a steady heartbeat. I was aware that this behavior was normal for cloud-connected devices. The DNS queries don’t exactly reveal the actual content being transmitted, but they do prove that these devices are dependent on external servers.

The noisiest device wasn’t the one I expected

Some gadgets talk more than others

I assumed the Alexa Echo would top the charts. It’s always connected to the internet. Its voice-triggered and relies heavily on cloud processing. But it wasn’t the Echo. It was the opposite. The Airtel Xstream TV box was the one with the highest number of DNS queries. There were frequent background lookups and multiple ad-related domain requests. There were a number of CDN endpoint calls even when the smart TV was idle.

The TV was off, and no active streaming or playback was in the background. I had no remote interaction with the Android TV box, yet it was still making DNS requests. It is also understandable that streaming platforms rely on ad networks. For a better experience, streaming apps need to preload metadata and sync with content catalogs and configuration data.

That’s when my curiosity turned into experimentation, and I decided to see what would happen if I blocked those requests more aggressively.

Blocking traffic changed how I see “smart”

Control comes with trade-offs

By default, Pi-hole comes with blocklists totaling around 80K entries. This was the first thing I wanted to improve, so I added the OISD blocklist with more than 300K entries on top of the defaults. This took the blocking to a more aggressive level. Pi-hole was now doing its job far more strictly. I did face a few hiccups, as it started blocking more aggressively and broke a few websites that I visit on a regular basis, like Google Analytics and the Mediavine Publisher portal. I had to manually move those domains to the allow list. Surprisingly, Safari’s private relay was affected by the aggressive filtering, making the browsing experience unstable.

With this experimentation, I came to realize that DNS filtering doesn’t mean full control, as smart devices depend heavily on cloud infrastructure. Privacy and convenience felt closely tied in this situation. I had to manually unblock several domains to make many services work.

Pi-hole didn’t make my home less smart — just less blind

I neither uninstalled any of my smart devices nor removed Pi-hole from the network. I didn’t aim for total isolation, but for visibility and control. I am now aware of how often these devices communicate and how dependent they are on external servers. This awareness changed how I manage my network.

Control isn’t about shutting down everything; it's about understanding what’s happening. My home didn’t get less smart. It just stopped being blind.