SCENARIO:
mydomain.com is the main website, we do send/receive mail using address@mydomain.com. mydomain.com DNS has got an SPF record
"v=spf1 a mx ~all"
mydomain.net is just an alias for mydomain.com, but we do NOT send mail using address@mydomain.net. Therefor mydomain.net DNS has got an SPF record
"v=spf1 -all"
to acknowledge everyone it does not send mail
Since mydomain.net is an alias for mydomain.com I wanted to use CNAME in DNS, thus:
mydomain.net -> CNAME -> mydomain.com
www.mydomain.net -> CNAME -> mydomain.com
But by doing this I noticed that when testing SPF for mydomain.net with a DNS tool like this the SPF returned is the one in mydomain.com "v=spf1 a mx ~all"
and NOT as I would expect the "v=spf1 -all"
Is there a way to use different SPF for the two domains, by still using CNAME