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Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minuteDNS records tell the internet how to find a service or handle a domain task. A and AAAA records point a name to IPv4 and IPv6 addresses; MX records route incoming email; TXT records carry service-specific text; NS records identify authoritative nameservers; and CNAME records make one name an alias of another. The correct values for a live domain come from its web host, mail provider, or DNS provider—not from a generic example.
What each DNS record means
| Record | What it tells DNS | Common use | Practical constraint |
|---|---|---|---|
| A | The IPv4 address for a name | Pointing a hostname to an IPv4-capable website or service | Use the address supplied by the service hosting it. |
| AAAA | The IPv6 address for a name | Making a hostname resolvable over IPv6 | Publish an address valid for the intended service. |
| MX | The mail exchanger for a domain, with a preference value | Routing incoming email to a provider’s mail servers | Lower numeric preference values are preferred. The target must not be a CNAME alias. |
| TXT | Text associated with a DNS name | Domain verification and email authentication, including SPF, DKIM, and DMARC | The required text and host/name field depend on the service being configured. |
| NS | The authoritative nameserver for a zone or delegated subdomain | Choosing where DNS for a domain or subdomain is managed | Delegation is different from adding ordinary host records; follow the registrar and DNS host’s instructions. |
| CNAME | The canonical target name for an alias | Pointing a name such as www to a provider hostname |
Under ordinary DNS rules, a name with a CNAME cannot also carry other record data. |
How to choose the right record
Pointing a website or application
Use an A record when the service gives you an IPv4 address, and an AAAA record when it gives you an IPv6 address. If the provider instead gives you a hostname to point to, it may instruct you to use a CNAME where the DNS rules and your provider’s setup allow one. Do not guess: the hosting service’s specified value determines the destination.
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Setting up incoming email
Add the MX hostnames and preference values supplied by your mail provider. If it supplies multiple MX records, the preference numbers order them; lower numbers are preferred. The MX target must be a hostname with address records, not a CNAME alias. Mail providers may also request TXT records for domain verification or email authentication. Copy the exact host/name and text they specify.
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A TXT record stores text at a DNS name. Services commonly use TXT records to confirm domain ownership or publish email-authentication data such as SPF, DKIM, and DMARC. TXT is only the record type: arbitrary text will not satisfy a service unless it matches that service’s required format and location.
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Changing authoritative DNS
NS records identify the nameservers authoritative for a zone or delegated subdomain. Changing delegation is not the same as editing a website’s A record or adding a TXT value. Follow the instructions from the registrar and the DNS provider responsible for the intended zone. Multiple nameservers are commonly used; Cloudflare’s guidance says delegation changes can take several hours to appear throughout DNS, but that is practical guidance rather than a guaranteed global deadline.
CNAME rules and common misunderstandings
A CNAME maps an alias name to another DNS name; it does not itself provide an IP address. A browser is not redirected to a different URL by a CNAME. DNS resolution and an HTTP redirect are separate operations.
Under ordinary DNS rules, the alias name containing a CNAME cannot also contain other record data such as A, MX, TXT, or NS records. For the same reason, an MX or NS target must not be a CNAME alias. Some DNS providers offer features such as CNAME flattening at a zone apex; these are provider-specific behaviors, not a change to the ordinary DNS rule. Cloudflare documents its own flattening and proxy behavior in its DNS record types documentation.
A CNAME target may itself resolve through another CNAME, but chains add lookup steps. Prefer a direct target when the provider supports one.
What TTL means when records change
TTL, or time to live, is the period a resolver may cache a DNS response before checking again. If you change a record, some users may continue to receive a previously cached answer while it remains valid. TTL does not promise an instant update worldwide, and provider defaults and controls vary. There is no single propagation time that applies to every DNS change.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Use examples as illustrations, not configuration values
For documentation purposes, www.example.test could be shown with an illustrative A record such as 192.0.2.10, or an illustrative AAAA record such as 2001:db8::10. These are examples, not server addresses to copy into a real domain. Your web host supplies the correct address or target; your mail provider supplies MX hosts and any authentication TXT strings.
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Sources and further reading
- Cloudflare Learning Center: DNS records
- Cloudflare Developers: DNS record types, last updated June 2, 2026. Its proxy, flattening, and dashboard details describe Cloudflare behavior.
- Cloudflare Learning Center: What is a DNS CNAME record?
- Cloudflare Learning Center: DNS NS record
- RFC 1035 (November 1987) defines the A record’s IPv4 address form as four decimal numbers separated by dots.
- RFC 2181 (July 1997) clarifies CNAME restrictions and the requirement that MX and NS targets not be aliases.
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