This article applies to:

• SEG/MailMarshal
  • Note change in behavior at version 7.1
• SPF (Sender Protection Framework) functionality

Question:

• How can I increase the recursion depth for SPF lookups?

Reply:

• In version 7.0 and below, the default value for allowed recursion depth of SPF records is 5.
• In version 7.1 and above this depth limit has been removed completely, because the standard (RFC 4408) does not include any limitations on depth. 

If you are using SPF and you encounter remote domains with complex SPF recursion, you should upgrade. (For instance, the microsoft.com domain has a complex recursion).

If you cannot upgrade immediately, contact Trustwave Technical Support for a workaraound.

Note:

In version 7.1 and above, you can change some SPF lookup parameters (such as maximum execution time) using registry settings. These parameters should not require change in a well connected production environment. For more information, contact Technical Support.