DNS Lookups

SPF : Too many included lookups !

SPF PermError: too many DNS lookups, is encountered when a user is rolling out or managing SPF. It arises when SPF 10-DNS-lookup limit is exceeded and such an error causes email deliverability issue.

Read more to know how you can fix this error.

Underlying reason behind the error

First and foremost, it is important to understand the underlying reason behind this error. We know that SPF has 10-DNS lookup limit and irrespective of your email exchanger, it generates 4 DNS lookups. For example, in case of Google’s Gmail, an SPF record like ‘v=spf1 include:[email protected] -all’ generates four DNS lookups. Considering nested and several third-party vendors to send messages from your domain, the limit of 10 DNS lookup limit is likely to exceed.

Issues with manual SPF flattening

SPF manual flattening replaces the include statements in the SPF record with the corresponding IP addresses and removes the need for lookups. It avoids the ‘permerror’ by ensuring too many DNS lookups are not generated.

Some of the issues with manual SPF flattening are given below:

  • SPF record length cannot exceed 255 characters.
  • Email service provider can modify/change/add to their IP address without any notification.
  • Lack of dashboard to monitor email flow, update domain and track activities.
  • Constant need of changes to the DNS to update SPF records.
  • Negative impact on email deliverability.

Cumulatively these issues are bound to fail SPF on the receiver’s side since SPF records are not updated on the new IP addresses email service providers are using.

Dynamic SPF Flattening to the rescue

A more refined and better solution to multiple DNS lookups is Dynamic SPF Flattener. It helps you in the following way:

  • Easy configuration to your domain.
  • One-click instant record flattening with a single include statement.
  • Helps in always maintain the 10 DNS lookup limit
  • Auto update netblock and scans new/changed IP addresses to keep SPF record up-to-date.
  • Always keeps a user-friendly dashboard wherein you can easily monitor changes to the policies, add domains and monitor email flows.

It is recommended to implement Dynamic SPF flattener instead of manual flattener to optimize SPF record and mitigate SPF hard limit.