How DNS Works
The Domain Name System translates human-readable domain names into IP addresses. When you type testrefy.com, your browser asks a recursive resolver for the IP address. The resolver queries root servers, then TLD servers, then authoritative name servers for the domain before returning the answer.
Essential DNS Record Types
- A record: Maps domain to IPv4 address
- AAAA record: Maps domain to IPv6 address
- CNAME record: Alias pointing to another domain
- MX record: Mail server for the domain
- TXT record: Verification and authentication (SPF, DKIM, site verification)
- NS record: Authoritative name servers for the domain
TTL and Propagation
TTL (Time to Live) controls how long DNS resolvers cache a record before checking for updates. A low TTL (300 seconds) is useful when planning DNS changes — set it low before changing, change it, then increase again. DNS changes can take up to 48 hours to propagate globally.
