SPF Record Essentials: How to Manage DNS for Email Security
To enhance email security, leveraging SPF (Sender Policy Framework) records is essential as an effective means of protecting your domain against email spoofing. In this article, we will discuss what SPF records look like and how to update them in your DNS settings.
What is an SPF Record?
SPF (Sender Policy Framework) records, a type of TXT (Text) record within DNS management, are critical in preventing unauthorized individuals from forging the From field in your emails. By setting up an SPF record, a domain owner can define a list of domains and IP addresses authorized to send emails on behalf of their domain, effectively safeguarding against email spoofing. This verification ensures that the emails are legitimately from you.
Much like a guest list at an exclusive event, SPF records control access to your email domain's reputation. The recipient's server acts like a security guard at a private banquet when an email is sent, checking if the sender's domain or IP address is on the SPF guest list. If it's not, the server will either reject the message outright or flag it as suspicious, like turning away an uninvited guest. This mechanism ensures that only approved senders can represent your domain, significantly reducing the risk of spoofing and enhancing your email security.
What Do SPF Records Look Like?
SPF records have required standards. This is how different mail servers can interpret the contents. However, understanding what you see when looking at the record can be confusing. Below are 3 examples of different SPF records.
v=spf1 include:spf.cloudus.oxcs.net ~all
v=spf1 ip4: 216.21.224.0/24 include:_spf.google.com include:domain.ext ~all
v=spf1 include:spf.registeredsite.com include:spf.cloudus.oxcs.net -all
Let’s use the table below to break down each aspect of the contents and see what each one means.
| Mechanism | Meaning |
|---|---|
| v=spf1 | The server knows this is an SPF record. All SPF records must start with this. |
| ip4: | One IPv4 address or a range of addresses can send messages from your domain name. |
| ip6: | One IPv6 address or a range of addresses can send messages from your domain name. |
| a:example.com | The mail servers on example.com are authorized to send messages from your domain name. |
| mx:mail.example.com | This MX record can send messages from your domain name. |
| include:spf.example.com | Third parties (such as your server or online store) are authorized to send email from your domain name. Your email messages may bounce if this isn’t included. |
| ~all or -all | ~all (recommended) Tells the receiving server to mark the message as suspicious (spam or insecure) and then deliver it. This is called a softfail. It helps the recipient understand that the sender needs to be validated. -all Tells the receiving server to reject a message from senders that are not included in the SPF record. This is called a hardfail. |
Updating an SPF Record
To update your SPF record, visit How Do I Manage DNS and Advanced DNS Records. If you manage your account at support.web.com, see How Do I Manage DNS and Advanced DNS Records in support.web.com.
Review
SPF records (Sender Policy Framework) are essential for email security. They specify which servers can send email from your domain, preventing spoofing. This safeguards your users from phishing attacks and improves your email deliverability. By creating an SPF record, you're taking a proactive step to protect your brand reputation and ensure the trust of your recipients.