Recently this domain has started to be used by e-mail spammers. (No, I do not run an open mail relay, they are simply spoofing random addresses with my domain as the extension.) As a result I’m getting delivery failure messages bouncing back to me from mail servers that are configured to return such things. So, I looked into implementing SPF on my domains. It won’t completely eliminate bounce messages, because not all mail servers check SPF records, but at least I will have done what I can.
My outgoing mail goes through my ISP’s mail servers, as many mail servers block mail sent directly from home Internet connections. It’s easy enough to use an “include” statement in the SPF record to allow another domain’s SPF recorded mail servers to relay mail for your domain. However, my ISP doesn’t publish SPF records for their mail servers. So the only other option is to include the IP address of their mail servers in my SPF record. The problem with this, is that Force9 have at least 9 outgoing mail servers, each of which has to be added individually and kept up-to-date. One mail server changing IP address could result in intermittent delivery failures which could be hard to detect.
I’ve tried raising the issue on the Force9 forums, but there hasn’t been any interest. So, Force9 / Plus.Net, please implement SPF on your mail servers!Pin It