Publishing SPF Records

Setting up your domain to support SPF records is as simple as setting up a DNS TXT record. Let’s say you have the domain, and it originates all email from users from the netblock The SPF TXT record for this domain is    IN    TXT    "v=spf1 ip4: -all"

If the owner of has MX machines that originate messages but that are not in the netblock, those can be added with the mx keyword. If the owner of wants to allow any host that ends in to be authorized to send email, then those can be added with the ptr keyword. The complete SPF record is    IN    TXT    "v=spf1 mx ptr ip4: -all"

The SPF web site ( ...

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