Sender Policy Framework (SPF) is an extension to the email transmitting protocol that allows email services to verify the origin of a received message, thus helping counter forged, unsolicited email (spam). Email services receiving email from the Runbox domains may verify that the messages actually originate with the Runbox servers by looking up the SPF information in the DNS records of our domains.

The SPF policy for Runbox’ own domains states that mail should come from the server IP addresses we specify otherwise the mail will fail the SPF tests done by the receiving servers.

Note: SPF records only indicate to the receiving email service what the domain owner’s policy is for that domain, they are not a guarantee of how the receiving email service will use the SPF information to determine what to do with a message, or that they check the SPF records at all. SPF is also not a way to guarantee a message doesn’t have a forged email address, but it does help to established whether the message was sent from an authorized email server.

Runbox Sender Policy Framework details

If you use your own domain with a Runbox account, and send email using our outgoing SMTP servers, you can use the Runbox SPF record as part of your domain’s configuration. This will ensure that other email services can verify that mail from your domain originates from the Runbox servers and is less likely to be forged.

To do this you must include the Runbox severs in your list of approved senders. The easiest way to do this is to modify your DNS records to include the text below in a TXT record of your zone file.

"v=spf1 redirect=spf.runbox.com"

The interface to your DNS management will most likely contain other fields that need to be completed, the values below should work fine (replacing domainyouown.com with your own domain).

Domain: domainyouown.com.
TTL: 3600
Record Type: TXT
Value: "v=spf1 redirect=spf.runbox.com"

Note: The “dot” at the end of the domain name can be significant in some interfaces and without it the record may not work. You might be able to refer to other records that you know work to see how they are formatted.

The SPF record above states that any server receiving email from your domain should check the SPF record at spf.runbox.com to see if the mail from your domain was sent from an allowed server.

There are other ways you can include the Runbox mail servers in an SPF record, but using the method above means you don’t have to worry if we change the IP addresses of our outgoing mail servers as we will update our record and your domain will redirect to that record.

Sending mail via Runbox and other email services

If you need to send email from your domain through servers other than Runbox, or in addition to Runbox and wish to include an SPF record you will need a different form of SPF record.

To send only via another email service, please see that services documentation for what the SPF record should be.

To send email via Runbox and another service, you might need something in the format below.

"v=spf1 include:spf.runbox.com include:spf.othermailservice.com -all"

In the case above spf.othermailservice.com represents what the other email service tells you the SPF record should be when using their mail servers. It may not always be as simple as the entry above, and we include this information here simply as a guide to the difference between using more than one mail service in an SPF record.

Note: When using more than one mail service like this, “redirect=spf.runbox.com” does not work alongside an “include:” entry and will result in an invalid SPF entry.
The above is an example and may not work in your specific case. If you need help with this please contact Runbox Support.

More information about SPF