SPF

[Anthony Bundy]

I have an pair of Ironport c350's as of yet, SPF is not enabled. We have an agency that has their own Filtering solution behind the IronPorts. They have SPF enabled, and one of their senders has also enabled SPF, and as you may have guessed, they are not receiving any mesages from the SPF enabled sender. As I understand it, SPF should be enebled on the IronPorts, and disabled on their end. The key being disabled on their end. Any input apreciated...

[Andreas Mueller]

Hello Anthony,

SPF originally was developed as a way to reduce spam, by including a specific data part in the DNS record of a domain stating which hosts or/and IP addresses are allowed to send mail for that particular domain. There is not such a thing like enabling SPF on a sending mail server, unlike you mean the entry in the DNS TXT records. On the receiving end, SPF check is optional, having it enabled means for each incoming message the receiver will look up the SPF records for the domain in the envelope from, and compare it with the IP the message comes from. So if something does not work, I suggest to have a look at the SPF part in DNS first, and check if it is in the right format, we often see mistakes there.

Regards, Andreas

[Anthony Bundy]

That makes sense. We do not have SPF setup on the DNS. They are attempting to use it from behind our IronPort. Thanks for the info!