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DNS Records Explained for People Who Ship Websites

A, AAAA, CNAME, MX, TXT and the TTL decisions that decide whether your migration is invisible or a two-hour outage.

Paj Digital Labs 1 min read

Records you will actually touch

  • A / AAAA — hostname to IP.
  • CNAME — hostname to another hostname. Never on the zone apex.
  • MX — mail routing, with priority values.
  • TXT — SPF, DKIM, DMARC and domain verification.

TTL is a migration tool

Drop TTL to 300 seconds a day before a cutover, migrate, verify, then raise it back. Skipping this step is why "the site is still on the old server" tickets exist.

Verify from outside your network

bash
dig +short A example.com @1.1.1.1
dig +short TXT example.com @8.8.8.8

Your local resolver lies to you. Always query a public resolver when confirming propagation.

Paj Digital Labs

The engineering journal of Paj Digital Solutions — hosting, server infrastructure and web engineering, written by the people who run the servers.

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