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spf flattening

SPF flattening: a practical guide for IT teams in 2026

TL;DR:SPF flattening replaces include mechanisms with static IP addresses to stay within DNS lookup limits. Automating this process is essential to maintain accurate records and prevent email delivery failures caused by stale IP data. SPF flattening is defined as the process of replacing include: mechanisms in an SPF

By Shaun Cooke

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