How to configure SPF Record?
This section defines HOWTO configure a Sender Policy Framework (SPF) record for a domain and its mail servers.
The SPF information SHOULD be defined in a standard TXT resource record (RR) and MAY now be defined in an SPF RR type (BIND releases from 9.4.0 support the SPF RR type RFC 4408).
The SPF RR is functionally identical to a TXT record with SPF data as text field:
TXT:name ttl class TXT text
SPF:name ttl class TXT SPF
Here are 2 examples of this DNS records:
TXT:example.com. IN TXT “description”
SPF:example.com. IN TXT “v=spf1 mx include:example.net -all”
Look at the record quotes in the text field. These quotes are required for proper operation.