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Reference · Glossary

SPF

Sender Policy Framework

Definition

A list, published in your domain’s records, of the servers allowed to send email for your domain.

In plain words

It tells other mail servers which senders are really yours. A domain has one SPF record; a new service is added inside it, never as a second record. The record may make at most 10 DNS lookups.

Why it matters to a firm

A missing or loose SPF record makes forged mail in your name easier to deliver, and a second record or an eleventh lookup makes the whole check fail.

The check behind the finding

nslookup -type=txt yourfirm.ca

Look for the one line that starts v=spf1. Ending in -all is strict; ~all is softer.

The outside watch for your firm: see what is open before anyone else does, with the proof for the lead finding. Check my firm →