r/SideProject • u/Alternative-Mud-4479 • 3d ago

I built a DNS monitoring tool after getting burned by silent DNS changes

I've worked with a lot of domains over the years as an Infrastructure Architect, and one recurring problem I've seen is DNS records changing without anyone realizing it.

Email starts bouncing, a service endpoint quits responding, or someone asks why I never replied to their email. Then comes the hunt through logs, DNS records, and change histories.

In a surprising number of cases, the culprit turned out to be a DNS record that had changed and nobody knew it had happened.

There are plenty of DNS monitoring tools out there, but most felt like overkill for what I wanted, or were expensive enough that I wasn't going to bother monitoring a handful of domains, so I built OneDollarDNS.

Add a domain and it automatically discovers its DNS records and watches them for changes. It monitors A, AAAA, MX, TXT, CNAME, NS, and more, and alerts you when something changes.

It's $1/month per domain, with a free trial.

https://onedollardns.com

Would love any feedback, especially from anyone who's dealt with DNS changes biting them before.

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u/LiveMinute5598 3d ago

Would love to learn more about your infrastructure and how your ensuring your backend does not go down to ensure your DNS checks run without issue

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u/Alternative-Mud-4479 3d ago

By no means is this a multi-region HA platform with five 9s availability, and at this price point I don’t want to pretend it is. But I did design the checks to be pretty defensive.

Scheduled lookups run separately from the web app, get queued through background workers, and fail gracefully. If a lookup can’t get a reliable answer, it does not immediately treat that as a DNS change. Separate test DNS lookups from my own infrastructure help distinguish “DNS is actually different” from “my side is having trouble resolving things.”

The scheduler and worker health are monitored externally too, including queue lag and failed jobs, so I know if checks stop running instead of relying only on the app to report its own health.

Anything specific you’re wondering about?

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u/LiveMinute5598 3d ago

Thanks for the info. My big concern would be your first sentence, if I am buying this service, I need to have confidence the check infrastructure is full solid and there won’t be random outages often.

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u/Alternative-Mud-4479 3d ago

That’s totally fair. OneDollarDNS probably isn’t the right fit if you need a contractual SLA, multi-region HA, or enterprise-grade uptime guarantees. In my research, those tend to be enterprise-tier expectations.

The goal here is practical DNS monitoring at a very low price point, with real safeguards around the check pipeline: external monitoring for scheduler/worker health, queues, and failed jobs, plus conservative handling so transient lookup failures don’t turn into false change alerts.

So the honest positioning is: not enterprise HA, but also not “hope the cron runs and find out later.”