Domain & DNS basics (simple explanation)

DNS is the system that translates your domain name (example.com) into the server that hosts your website and email. Understanding a few record types helps you troubleshoot issues and make changes safely.

The records you must know

• A record: points a hostname to an IPv4 address (e.g. @ → 203.0.113.10).
• AAAA record: points to an IPv6 address.
• CNAME: aliases one hostname to another (e.g. www → @ or to a CDN hostname).
• MX: tells the world which mail servers receive email for your domain.
• TXT: stores text values used for verification and email security (SPF/DKIM/DMARC).
• NS: nameservers that control the DNS zone (changing NS moves DNS management to another provider).

TTL and propagation (what people call “DNS delay”)

DNS changes are cached. TTL (time-to-live) defines how long resolvers cache a record. Lower TTL before a migration so changes propagate faster, then increase it after things stabilize.

Common mistakes and how to avoid them

• Mixing A and CNAME at the root: root (@) should usually be an A/AAAA record.
• Breaking email by changing MX: always document current MX/TXT before switching.
• Forgetting “www”: set www as CNAME to your main host if needed.

Quick checklist before you edit DNS

1. Export current zone records (screenshot or copy).
2. Lower TTL (e.g. 300 seconds) a few hours before big changes.
3. Change one thing at a time and verify.
4. Monitor website + email for 24 hours.

FAQ

How long does DNS propagation take? Usually minutes to a few hours, but can be up to 24–48 hours depending on caches and TTL.

Should I use a CNAME for “www”? Yes in most cases; it makes changes easier.