Multi-Layered DNS

Is Multi-Layered DNS Filtering the Ultimate in Flexibility?

When it comes to managing network traffic at home, most people think a single DNS filtering solution is enough. I beg to differ. For me, layering multiple DNS filtering services has unlocked a level of flexibility that suits my technical needs. However, before you rush to implement a similar setup, let’s explore what it entails, the pros and cons, and whether it’s right for you.

What is DNS Filtering?

At its core, DNS (Domain Name System) filtering works by blocking access to specific domains. Think of it as a gatekeeper that decides whether a device in your network can visit a particular website or service. Common use cases include:

  • Blocking malicious sites for enhanced security.
  • Filtering inappropriate content (e.g., parental controls).
  • Enforcing productivity by restricting social media during work hours.

Most DNS filtering solutions operate on a single layer—you set it up at the router or device level, and that’s it. Simple, right? Well, I wanted more.

Why Multiple Layers?

One DNS filtering service alone often lacks the granularity I desire. By combining multiple layers, I can fine-tune access rules, segment devices, and even allow for selective bypassing when needed. Here's how I’ve structured my setup:

  1. Primary DNS Filter:
    • This sits at the router level (e.g., OpenDNS or CleanBrowsing) and provides a broad, network-wide filtering policy.
    • It’s perfect for catching the obvious bad actors—malware domains, phishing sites, etc.
  2. Per-Device Overrides:
    • Using a service like NextDNS, I set up profiles for individual devices. For example, my work laptop follows stricter productivity rules, while my gaming console has fewer restrictions.
  3. Local DNS Resolver:
    • To add a final layer of control, I run a local DNS resolver (e.g., Pi-hole) that blocks ads and trackers at a granular level. This also gives me detailed analytics about DNS queries on my network.

Benefits of a Multi-Layered Approach

  1. Granular Control:
    • Different devices can follow different rules.
    • Time-based filtering is easier to enforce.
  2. Redundancy:
    • If one DNS service goes down, another layer picks up the slack.
  3. Privacy:
    • A local resolver ensures that sensitive DNS queries stay within my network.
  4. Customisation:
    • I can whitelist or blacklist domains on a per-device basis.

The Downsides

  1. Complexity:
    • Managing multiple layers requires technical knowledge and constant tweaking. It’s not a set-it-and-forget-it solution.
  2. Performance:
    • DNS lookups might be slightly slower due to the additional processing.
  3. Costs:
    • Some premium DNS filtering services charge subscription fees.
  4. Overkill for Many Users:
    • If you don’t have specific needs, a single-layer solution might suffice.

Is This Setup Right for You?

This approach isn’t for everyone. If you value simplicity and don’t need highly customisable filtering, stick with a single-layer solution. Services like Google SafeSearch or your router’s built-in parental controls might be all you need.

However, if you:

  • Enjoy tinkering with network setups.
  • Have diverse devices with different needs.
  • Want ultimate control over what enters and leaves your network.

Then multi-layered DNS filtering might be your next DIY project.

Final Thoughts

For me, layering DNS filtering has been a game-changer. It’s given me the flexibility to manage my home network exactly the way I want. But I’ll admit, it’s not for the faint of heart. The real question is: how much control do you really need?

Let me know in the comments—is multi-layered DNS filtering something you’d try, or is it too much hassle?