Authentication

What is SPF?

Sender Policy Framework (SPF) is an email authentication method that specifies which mail servers are authorized to send email on behalf of your domain, helping prevent email spoofing.

SPF (Sender Policy Framework) is an email authentication protocol that helps prevent spammers from sending emails that appear to come from your domain. It works by allowing domain owners to publish a list of authorized mail servers in their DNS records.

When someone sends an email claiming to be from your domain, the receiving mail server checks your SPF record to see if the sending server is authorized. If the server is on the list, the email passes SPF authentication. If not, the email fails SPF and may be rejected or marked as spam.

An SPF record is a TXT record in your DNS that looks something like: "v=spf1 include:_spf.arkhq.io ~all". This tells receiving servers to accept emails from Ark's servers and to soft-fail emails from any other source.

Why SPF Matters

SPF is your first line of defense against email spoofing. Without it, attackers can easily send emails that appear to come from your domain, potentially tricking your customers into revealing sensitive information or clicking malicious links. Email providers heavily weight SPF in their spam filtering decisions, so missing or incorrect SPF records can cause your legitimate emails to end up in spam.

How Ark Handles SPF

When you add a sending domain to Ark, we provide the exact SPF record you need to add to your DNS. Our SPF include mechanism ensures all emails sent through Ark pass SPF authentication. We also monitor your SPF record health and alert you if any issues are detected.

Frequently Asked Questions

What does 'SPF too many DNS lookups' mean?

SPF records are limited to 10 DNS lookups. If your SPF record includes too many external services, it can exceed this limit and fail. Ark's SPF mechanism is optimized to minimize lookups while still providing full authentication.

Should I use ~all or -all in my SPF record?

~all (soft fail) is recommended when first setting up SPF, as it flags unauthorized emails without rejecting them. Once you're confident your SPF record includes all legitimate senders, you can switch to -all (hard fail) for stricter enforcement.

Can I have multiple SPF records?

No, you should only have one SPF record per domain. Multiple SPF records can cause authentication failures. If you use multiple email services, combine them into a single SPF record using 'include:' mechanisms.

How do I check if my SPF record is correct?

You can use online SPF validators or check your email headers for SPF results. Ark's domain verification automatically checks your SPF record and alerts you to any issues.

Related Terms

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Email Authentication

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DNS Records

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