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Published: 2026-07-06 | Updated: 2026-07-06
DNS records tell the Internet how to connect your domain to websites, email, SSL validation, apps, verification services, and security settings. A points to IPv4, AAAA points to IPv6, CNAME points one hostname to another, MX controls email delivery, TXT stores verification and email authentication, CAA controls SSL certificate authorities, and SRV defines service locations for certain apps.

Who This Guide Is For
This guide is for:
· Users learning DNS basics
· Website owners setting up domains
· Business Email users
· Agencies and hosting providers supporting DNS questions
· Users troubleshooting website, email, SSL, CDN, or app connections

Before You Start
Before you start, prepare:
· DNS provider access
· Current nameservers
· DNS backup
· Provider instructions for website or email
· Permission to edit records
· Understanding of affected service

Step-by-Step Instructions
Step 1: Understand DNS Records
DNS records are instructions for website, email, verification, SSL, apps, and security.
· One domain can have many records
Step 2: A Records
A records point hostnames to IPv4 addresses.
· Common for root website and subdomains
Step 3: AAAA Records
AAAA records point hostnames to IPv6 addresses.
· Wrong IPv6 can cause issues for some users
Step 4: CNAME Records
CNAME points one hostname to another hostname.
· Use for www, CDN, website builders, and apps
Step 5: MX Records
MX controls where email is delivered.
· Copy priority values carefully
Step 6: TXT Records
TXT stores text for verification and authentication.
· SPF, DKIM, DMARC, Google, Microsoft, SSL, SaaS
Step 7: SPF Records
SPF is a TXT record listing authorized sending servers.
· Avoid multiple SPF records for same host
Step 8: DKIM Records
DKIM is a TXT or CNAME record used for email signing.
· Copy long values exactly
Step 9: DMARC Records
DMARC tells receivers how to handle SPF/DKIM failures.
· Start carefully before strict policies
Step 10: CAA Records
CAA controls which certificate authorities may issue SSL certificates.
· Restrictive CAA can block SSL issuance
Step 11: SRV Records
SRV defines service location for apps such as voice, chat, or collaboration.
· Copy priority, weight, port, and target
Step 12: NS, SOA, PTR, and DNSSEC Records
NS identifies nameservers, SOA describes the zone, PTR is reverse DNS, and DNSSEC records support validation.
· Most users do not manually edit SOA or all DNSSEC records
Step 13: TTL
TTL controls cache time for records.
· Lower in advance for planned migrations if appropriate

Troubleshooting
Website Is Down
Possible reasons:
· Wrong A/AAAA/CNAME
· Wrong nameservers
· DNSSEC issue
What to do:
· Check active DNS provider and records

Email Not Receiving
Possible reasons:
· MX missing
· SPF/DKIM/DMARC wrong
What to do:
· Restore email records

SSL Cannot Be Issued
Possible reasons:
· CAA blocks CA
· TXT/CNAME validation missing
What to do:
· Review CAA and validation records

Verification Fails
Possible reasons:
· Record added at wrong provider
· Host field wrong
What to do:
· Check authoritative nameservers and exact value

Common Mistakes
Mistake 1: Editing DNS at wrong provider
Review this item before making changes or opening a support ticket.
Mistake 2: Deleting unknown TXT records
Review this item before making changes or opening a support ticket.
Mistake 3: Forgetting MX during migration
Review this item before making changes or opening a support ticket.
Mistake 4: Creating multiple SPF records
Review this item before making changes or opening a support ticket.
Mistake 5: Confusing CNAME with A record
Review this item before making changes or opening a support ticket.
Mistake 6: Forgetting CAA
Review this item before making changes or opening a support ticket.
Mistake 7: Ignoring DNSSEC
Review this item before making changes or opening a support ticket.
Mistake 8: Using wrong host field
Review this item before making changes or opening a support ticket.
Mistake 9: Not copying MX priority
Review this item before making changes or opening a support ticket.
Mistake 10: Changing too many records at once
Review this item before making changes or opening a support ticket.

FAQ
1. What is an A record?
It points to an IPv4 address.
2. What is AAAA?
It points to an IPv6 address.
3. What is CNAME?
It points one hostname to another hostname.
4. What is MX?
It controls email delivery.
5. What is TXT?
It stores verification, authentication, and security text.
6. What is SPF?
A TXT rule for authorized mail senders.
7. What is DKIM?
An email authentication record, usually TXT or CNAME.
8. What is DMARC?
A TXT policy for handling failed mail authentication.
9. What is CAA?
It controls certificate authority issuance.
10. What is TTL?
How long DNS may be cached.
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