Practical IT Guide

DNS Records Explained

DNS troubleshooting is easier when you know what each record type is intended to do.

Reviewed by Ahmed Gaber · Published September 12, 2026 · Updated September 15, 2026

Start with A and AAAA

A records map names to IPv4 addresses, while AAAA records map names to IPv6 addresses.

Check aliases and nameservers

CNAME records create aliases and NS records identify the authoritative DNS servers for the zone.

Review TXT records carefully

TXT records often carry email-authentication, ownership-verification and service configuration data.

Compare with the intended service

A record can exist and still be wrong. Confirm values against the hosting, mail or SaaS service that should receive traffic.

Use this as a practical starting point. Follow your organization's policies, licensing requirements and vendor documentation for production changes.

Next steps

Turn the guide into action.

Use a related utility, checklist or follow-up guide to complete the workflow.

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FAQ

Common questions

What should I check first when a domain stops resolving?

Start with the authoritative nameservers, then verify A, AAAA or CNAME records against the service that should receive the traffic.

Can a DNS record exist and still be wrong?

Yes. A syntactically valid record can point to the wrong host, use an old provider, or conflict with the intended service design.

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