---
title: "DNS A record change check — Lemwatch Help"
description: "Lemwatch hashes your A records every hour and alerts when the IP list changes — a fast signal for hijacks, misdeploys, or accidental DNS edits."
canonical: "https://lemwatch.com/help/dns-a-record-change-check"
source: "https://lemwatch.com"
---

# DNS A record change check

> Lemwatch hashes your A records every hour and alerts when the IP list changes — a fast signal for hijacks, misdeploys, or accidental DNS edits.

## Quick answer

 Lemwatch resolves your domain's A records hourly, hashes the sorted IP list, and alerts when the hash changes vs the previous cycle.

## What it checks

- All IPv4 A records for the apex and www

- Sorted-set hash so record order doesn't cause false positives

- Detects additions, removals, and swaps

- Cross-checked against 3 public resolvers to filter local anycast noise

## Where to find it in Lemwatch

 **Site details → Health → DNS tab.** Change events also surface in Activity Log with a "DNS change" pill.

## How to respond

- Open the DNS tab to see old vs new IPs side-by-side.

- Confirm the change matches a planned deploy or DNS migration.

- If unplanned, check your registrar audit log for unauthorised edits.

- Add the new IPs to your CDN allowlist if you use origin protection.

- Acknowledge the alert to silence follow-ups for that IP set.

## FAQ

### Will this alert on healthy round-robin rotations?

 No — the sorted-set hash treats [1.1.1.1, 2.2.2.2] and [2.2.2.2, 1.1.1.1] as identical.

### How fast is the alert?

 Within one hourly cycle. Pro plans can drop this to 15 min.

## Related

- DNS diagnostics

- DNS CNAME change check

- DNS NS record check


## Related

- [Help centre](https://lemwatch.com/help)
- [DNS Diagnostics](https://lemwatch.com/help/dns-diagnostics)
- [DNS CNAME change check](https://lemwatch.com/help/dns-cname-change-check)
- [DNS NS record check](https://lemwatch.com/help/dns-ns-record-check)
- [DNS MX record check](https://lemwatch.com/help/dns-mx-record-check)
- [Lemwatch pricing](https://lemwatch.com/pricing)
- [How does Lemwatch detect DNS record changes?](https://lemwatch.com/help/dns-change-monitoring)
- [DMARC record check](https://lemwatch.com/help/dmarc-record-check)