Monitoring

    DNS MX record check

    Monitors MX records so a fat-fingered mail edit or expired provider does not silently break customer email.

    Part of DNS monitoring — the full answer, the facts and the alternatives in one place.

    Updated 2026-07-10
    1 min read
    dns
    mx
    email

    Quick answer#

    Lemwatch hashes your MX priority+host set hourly and alerts when it changes or when zero MX records are returned.

    What it checks#

  1. All MX hosts with their priorities
  2. Zero-MX condition (mail delivery will fail)
  3. Whether MX targets resolve (dangling MX)
  4. Cross-check against 3 resolvers

    5. Where to find it in Lemwatch#

    Site details → Health → DNS tab → Mail.

    How to respond#

  5. Confirm the new MX matches your mail provider (Google, Microsoft 365, Fastmail).
  6. If zero-MX, restore records from your registrar backup.
  7. Send a test email through a monitored inbox.
  8. Update SPF to include the new mail provider (see SPF record check).
  9. Acknowledge.

    10. FAQ#

    Does Lemwatch send real email to test?#

    No — DNS record inspection only, no mail traffic.

    What if I have no MX and use a Null MX?#

    Null MX (0 .) is recognised and treated as intentional.

    Related#

  10. DNS A record change check
  11. SPF record check
  12. DMARC record check
    13. Was this article helpful?

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