I need to configure SPF record for a subdomain.
DNS for the main domain (I use Google Mail):
IN MX 1 aspmx.l.google.com.
IN MX 10 aspmx3.googlemail.com.
IN MX 10 aspmx5.googlemail.com.
IN MX 10 aspmx4.googlemail.com.
IN MX 10 aspmx2.googlemail.com.
IN MX 5 alt1.aspmx.l.google.com.
IN MX 5 alt2.aspmx.l.google.com.
IN TXT "v=spf1 ip4:xx.xxx.xxx.xx include:_spf.google.com ~all"
mysubdomain IN A xxx.xxx.xxx.xxx
But how to set SPF for mysubdomain.example.com ? I will send email newsletter from this subdomain using phpmail.
Also online email checkers show warning that there is no MX record for my subdomain.
Just add the subdomain in front of the SPF record:
mysubdomain IN TXT "v=spf1 ip4:xx.xxx.xxx.xx include:_spf.google.com ~all"
Similarly, you can set a separate MX, though you don't necessarily need one if it's the same as for the domain:
mysubdomain IN MX 1 aspmx.l.google.com.
mysubdomain IN MX 10 aspmx3.googlemail.com.