Introduction
DNS is the system that helps connect domain names to internet services.
When someone visits your domain, DNS helps their device find the correct website infrastructure.
DNS also plays a major role in business email, verification and security settings.
You do not need to become a network engineer, but understanding the common record types can prevent expensive mistakes.
A and AAAA Records
An A record points a hostname to an IPv4 address.
An AAAA record serves a similar role for IPv6.
These records are commonly used to direct a domain or subdomain toward web infrastructure.
Changing them can move traffic away from the current server.
CNAME Records
A CNAME points one hostname to another hostname.
Services often use CNAME records for subdomains, verification or hosted platforms.
Provider instructions should be followed exactly.
Do not create conflicting records for the same hostname without understanding the DNS provider's behavior.
MX Records
MX records tell mail systems where email for the domain should be delivered.
They are critical for business email.
A website migration should not casually replace or remove MX records.
Document them before changing DNS providers or nameservers.
TXT Records
TXT records are used for many verification and policy purposes.
Email systems use them for SPF, DKIM references and DMARC-related configuration.
Search and SaaS platforms may also request TXT verification.
Do not delete unfamiliar TXT records simply because they do not point to a website.
Nameservers
Nameservers determine which DNS provider is authoritative for the domain.
Changing nameservers can effectively replace the complete DNS zone.
Before a nameserver migration, copy every required website, email and verification record.
This is one of the most common ways a website migration accidentally breaks email.
TTL and Propagation
DNS records use a time-to-live value that influences how long resolvers may cache information.
Changes do not always appear to every user instantly.
Plan important migrations rather than making last-minute DNS changes.
Keep the old service available during transition when practical.
Who Should Control DNS?
The business should know which provider hosts DNS and maintain recoverable account access.
Developers may need permissions to make changes.
Record important entries in internal documentation.
DNS should not exist only in one contractor's memory.
Frequently Asked Questions
Is DNS the same as hosting? — No. DNS points the domain toward services, while hosting runs the website or application.
Can changing website hosting break email? — It can if DNS records are changed incorrectly, especially MX and related TXT records.
How long do DNS changes take? — It varies by caching and record TTL; some updates appear quickly while others take longer to be seen everywhere.
Should my developer own DNS? — They can manage it, but the business should retain recoverable control of the account.