SOA record

The "start of authority" for a zone: primary nameserver, administrative contact, serial number and the timers that govern secondary servers.

What one looks like

example.com. 3600 IN SOA ns1.provider.com. hostmaster.example.com. 2026082601 7200 3600 1209600 3600

Things worth knowing

  • The serial number should increase with every zone edit; secondaries use it to know they must update.
  • The final number is the negative caching TTL — how long a "does not exist" answer is remembered.
  • Every zone has exactly one SOA.

Look up a SOA record yourself

dig (macOS / Linux)

dig SOA example.com +short

nslookup (any OS)

nslookup -type=SOA example.com

Your resolver may still be serving a cached copy — our propagation checker queries 30+ resolvers worldwide so you can see who already has the new SOA record.

Look up a real SOA record

Query any domain live and see every record type with its TTL.

Run a DNS lookup