Definition
SPF DNS is a TXT record listing the servers allowed to send mail for your domain. Receivers use it to validate the envelope sender.
Keep records concise and within the DNS lookup limit.
SPF is the first authentication layer, and its DNS record is where delivery validation starts. Keeping the record concise and within lookup limits prevents failures. Reviewing it when you change providers avoids gaps.
Managing SPF
Keep SPF records short and within the DNS limit.
List all legitimate sending hosts and no more.
Why It Matters
SPF is the first authentication layer, and its DNS record is where delivery starts. Understanding it prevents the most common authentication failures.
Best Practices
- Keep SPF records short and within the DNS limit.
- List all legitimate sending hosts and no more.
- Review records when you change providers.
- Use include for third-party senders.
- Monitor SPF pass rates.
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Frequently Asked Questions
It authorises certain servers to send from your domain. SPF is the first authentication layer, and its DNS record is where delivery validation starts.
Too many lookups can break SPF validation. Keeping the record concise and within lookup limits prevents failures.
Poorly; that is why DKIM and DMARC add context. Reviewing it when you change providers avoids gaps.
Ten lookups max. SPF is the first authentication layer, and its DNS record is where delivery validation starts.
Use a DNS lookup or authentication checker. Keeping the record concise and within lookup limits prevents failures.