DNS Records Explained

What DNS Does

DNS turns names into destinations. When someone visits a domain, DNS tells their browser which server should answer. It also tells mail servers where to deliver email and lets services prove domain ownership.

Bad DNS changes can break websites, email, SSL, and third-party services, so it is worth understanding the common records.

A and AAAA

An A record points a name to an IPv4 address. An AAAA record points a name to an IPv6 address.

For a typical website, example.com and www.example.com may point to the web server using A records, AAAA records, or both.

CNAME

A CNAME points one name at another name. It is commonly used for www, CDN records, verification records, and hosted services.

Do not use a CNAME at the root of a domain unless your DNS provider supports ALIAS or ANAME-style flattening.

MX

MX records tell the internet where to deliver email for the domain. If MX records are wrong, mail may bounce or go to the old provider.

Changing website hosting should not require changing MX unless email hosting is moving too.

TXT, SPF, DKIM, and DMARC

TXT records store text values used by many services. Email authentication relies heavily on TXT.

SPF lists which servers may send mail for the domain. DKIM publishes keys used to verify signed messages. DMARC tells receivers what to do when SPF and DKIM checks fail.

NS

NS records define which nameservers are authoritative for the domain. Changing nameservers moves DNS control to another provider.

Do this carefully. If the new zone is missing records, the site or mail can break even if the domain itself is fine.

TTL

TTL controls how long DNS answers can be cached. Lower TTL before migrations. Raise it later for stability.

Verdict

DNS is simple until it is not. Before changing records, export or screenshot the current zone and understand whether you are moving website hosting, email hosting, or nameserver control.

See our guides on [Domain Registrar Guide](/guides/domain-registrar-guide), [Email Hosting Options](/guides/email-hosting-options), and [How to Migrate Email Hosting](/guides/how-to-migrate-email-hosting).