Hello,
My companies have 10 domains but we only use ONE of 10 domains for sending mail.
So in DMARC record for those 9 unused domains, should I just simply apply “p=reject” for them?
Unused domains should be marked as such using SPF and DMARC DNS TXT records:
@ IN TXT “v=spf1 -all”
_dmarc IN TXT “v=DMARC1; p=reject; rua=mailto:…”
The rua tag and reporting address can be omitted if you do not want to know about attempted abuse.
2 Likes
Something else that you might look at, if you haven’t already, is creating a null MX record for the domains
3 Likes
Hi beekeeper,
Thanks for your suggestion.
Unfortunately, my domain provider does not support null MX record.
I also read some articles which suggest to use private IP or “localhost.” instead of . in target host.
