example.com. IN TXT v=spf1 a mx -all
How to read this line.
The first part (example.com.) tells the world we are only talking about email with @example.com addresses. If you use a different domain name in the email you send, change it here.
The second part (IN) and third part (TXT) are just DNS information talking about how this record is communicated to others. If you are using the IPAD-OS's web manager, these important parts will be automatically added for you.
The fourth part (v=spf1) tells the world this is a record using the SPF version 1 format. New versions of SPF can be created at any time and it won't change the effectiveness of this record.
The fifth part (a) tells the world if they look up the IP address (the A record) for the domain name used on the email address (example.com), the machine that lives at that IP address is allowed to send email.
The sixth part (mx) tells the world any machine that is listed with an MX (Mail Exchange) record for this domain is allowed to send email.
The last part (-all) tells the world that this is the whole story. No other machines are allowed to send email using this domain name.
Add the record above to your DNS zone file.
This is a fully qualified record. You should replace the
example.com part with the domain name you use on your email, not the domain name of your email server. Remember that there must be a period at the end of the domain name to make this a fully qualified record.
This record would probably be the same for any other domain hosted on your IPAD-OS. Simply change the "example.com." part to other domain names and add the new line to the zone file for that domain.
For more information about SPF and ways to refine the rule description for your domain, please visit the spf.pobox.com site.