DIAGNOSTIC PLAYBOOK
Authoritative nameservers disagree on email records
Different authoritative answers can make email checks appear inconsistent without any cache issue. A partially synchronized zone may publish different MX or authentication policies depending on which server answers.
HealthCheck Email editorial team · · Examples are illustrative
How to investigate
- List the zone's authoritative nameservers and query each one for the affected record.
- Compare serials and record values where available, recording response time and server.
- Resolve the zone publication or secondary synchronization issue with the DNS operator.
What this looks like
ILLUSTRATIVE EXAMPLE
One authoritative server has the new MX and another still has the old destination. Senders can receive either answer even after ordinary caches expire.
A mistake to avoid
Repeated public-resolver checks cannot prove authoritative consistency. Query the individual authorities to identify the publication split.
Keep the result in context
The authoritative DNS service publishes records; recursive resolvers may retain earlier answers until their cache expires. Save the queried name, record type, resolver, answer and time. A website loading correctly does not establish that email records are present or that an SMTP server accepts mail.
Take the next step
Use the related check to gather evidence, then compare it with the affected message or service. Keep the result and time with your notes so a later change can be distinguished from the original problem.
Sources and further reading
The protocol references below explain the underlying behavior. Your sending or DNS provider supplies the account-specific settings for its service.