Does a SPF record apply only on the domain it’s setup for or also for all it’s subdomains?
For example an SPF record that is configured for the domain
example.com will set the policy for mails ending with
So if that is the only SPF record, does it also apply on mails send from mail addresses ending with
@www.example.com? Or should a second SPF record for the
www subdomain be configured (and so for all other subdomains)?