About SPF records

An SPF record is a type of Domain Name Service (DNS) record that identifies which mail servers are permitted to send email on behalf of your domain.

The purpose of an SPF record is to prevent spammers from sending messages with forged From addresses at your domain. Recipients can refer to the SPF record to determine whether a message purporting to be from your domain comes from an authorized mail server.

For example, suppose that your domain myorg.org uses CERVIS to send email. You create an SPF record that identifies the CERVIS mail servers as authorized mail servers for your domain. When a recipient's mail server receives a message from user@myorg.org, it can check the SPF record for myorg.org to determine whether it is a valid message. If the message comes from a server other than the mail servers listed in the SPF record, the recipient's mail server can reject it as spam.

If your domain does not have an SPF record (or if the CERVIS mail servers are not included in your existing SPF record), some recipient domains may reject messages from your users because they cannot validate that the messages come from an authorized mail server.

If you've already created an SPF record for your domain, you will need to add the CERVIS mail servers into your existing SPF record. 

The UI and terminology may vary depending on your registrar, but the concepts are the same.

Configure SPF records to work with CERVIS

Create an SPF record for your domain

1. Log in to the administrative console for your domain.
2. Locate the page where you can update the DNS records.
   You may need to enable advanced settings.
3. Create a TXT record containing this text: v=spf1 include:_spf.cervistech.com ~all
   
   Publishing an SPF record that uses -all instead of ~all may result in delivery problems.
   
   To authorize an additional mail server, add the server's IP address before just before the ~all argument using the format ip4:address or ip6:address. (See Sender Policy Framework for more details on the SPF format.)
4. Save your changes.

Your new SPF record can take up to 48 hours to go into effect, but this usually happens more quickly.

Check your existing SPF record

You can use the link below to check if your domain has an existing SPF record and whether or not your existing SPF includes the CERVIS mail servers.

• http://mxtoolbox.com/spf.aspx

Avoid adding multiple SPF records

Adding more than one SPF record for a domain can cause problems with mail delivery and spam classification. Instead, we recommend using only one SPF record. 

Multiple SPF records are not recommended and may cause delivery and spam classification issues. According to RFC specs, a domain name must not have multiple records that would cause an authorization check to select more than one record.

If you need to authorize more than one mail server for your domain, we recommend that you update your existing SPF record instead of creating multiple records.

Example

• v=spf1 ip4:184.173.191.234 ~all
• v=spf1 include:_spf.cervistech.com ~all

This text will cause the SPF check to fail because there are multiple records. Instead, add the mail server's IP address before the ~all argument using the format ip4:address or ip6:address to add the server to your existing SPF record:

• v=spf1 ip4:184.173.191.234 include:_spf.cervistech.com ~all

For more details on the SPF format, see Sender Policy Framework.