One final important mechanism to discuss is the "include" mechanism. This allows you to specify another domain so that any sender in that domain's SPF record is also allowed under yours. When the include mechanism is encountered, the sending mailserver is checked against the SPF data for the domain named, and if it matches there, the SPF check passes for your domain. This allows you to make provisions for service providers whose servers may sometimes be used in sending email from your domain.

The above record would indicate servers specific to your domain, and include any mailserver which is allowed to send email for easydns.com. You would need to include this if you are using our mailforwarding.

SPF can create problems in email forwarding since the forwarding mailserver would not be listed in the sending domain's SPF data. For this reason you would also want to have your email provider "whitelist" any mailservers you use for forwarding to your email account, if that email provider is enforcing SPF on their mailservers. A server which is whitelisted by the receiving mailserver is not subjected to an SPF check, since it has been listed as an acceptable source of email. If you are using easyDNS email forwarding and your email provider is enforcing SPF, you will want to contact them and have them whitelist smtp.easydns.com and smtp2.easydns.com for your domain to avoid these problems.