Every time you query your DNS, it costs the validator (the recipient’s email system) resources like bandwidth and CPU memory. A maximum limit of 10 DNS lookups is imposed to avoid unreasonable load on the validator. If an SPF record exceeds this limit, SPF too many DNS lookups error or technically called the ‘Permerror’ comes up.
Causes of SPF Too Many DNS Lookup Errors
Domain administrators or owners come across the SPF permerror too many DNS lookups issue due to the reckless use of the ‘include’ or the ‘redirect’ modifiers. This even results in a deteriorated email deliverability rate which hampers PR, marketing, and other email-based campaigns.
What Happens if SPF Record DNS Lookup Limit is Exceeded?
When the SPF too many DNS lookup limit is reached, emails sent from that domain don’t reach the desired recipients’ inboxes. Gmail sends such emails to the spam folder, and Microsoft Office 365 blocks these domains automatically if they fail SPF authentication.
How to Fix SPF Too Many DNS Lookups?
Use ip4 and ip6
The ip4 and ip6 mechanisms list a static IP range in the SPF record. They reduce the include statements as well.
Remove ptr and mx Mechanisms
Using ptr and mx mechanisms require more DNS lookups which causes reaching the limit quickly.
Remove include Statements
The include statement allows third-party vendors to send emails using your domain. You should remove include statements that direct SPF checks to senders who don’t send emails on your behalf anymore. This reduces the likelihood of getting SPF too many DNS lookups issue.
SPF Flattening
AutoSPF’s automatic SPF flattening service replaces all the domains in an SPF record with their IP addresses so that you don’t have to perform SPF DNS lookups. However, manual SPF flattening requires constant monitoring and proper configurations, which is difficult to come by.
That’s why we at AutoSPF offer an SPF flattening and notification services for your email-sending domain so that you never face SPF errors for too many DNS lookups.
