The record that makes recovery possible.
WHAT TO RECORD
Where the domain is registered, and the renewal date Which nameservers are in use Where DNS records are held Who has access to each, and how A full zone export Any glue records, if you run private nameservers Whether DNSSEC is enabled Verification records and which service each belongs to
THAT LAST ONE
The most useful and least kept. A zone full of TXT records nobody can identify is impossible to maintain safely.
Note what each is for.
WHERE TO KEEP IT
Off the hosting account, with your site documentation.
Credentials in a password manager.
WHY
During an incident you need this immediately and cannot investigate.
If someone else must act in your absence, this is what makes it possible.
UPDATING IT
After any change. A document describing last year's configuration misleads.
THE MINIMUM
Registrar, nameservers, where records live, and a zone export.
Four things, ten minutes, covering most of what goes wrong.
