Updating an SPF / TXT record


Well-Known Member
Sep 26, 2006
cPanel Access Level
Root Administrator
I have few questions regarding the SPF filter. I've checked a few online tutorials, and I'm still not clear, so any clarification at all would be appreciated!

1. When writing the SPF record, do I need to list the IP and MX record that's already in the DNS, or only those that are not listed? For example, if I have an A entry of:

example.com. A

Then does my SPF need to say:

"v=spf1 a mx ip4: mx:example.com -all"

Or does it just need:

"v=spf1 a mx -all"

2. I've read that I should include "ptr" if all of the reverse DNS records resolve to outbound email servers for the domain. How do I test to see if this is true?

3. I see several references to a SPF filter that's separate from the TXT record. Is this something I should create somewhere else, or is it just something that WHM doesn't have in it's DNS zone section yet?


Staff member
Apr 11, 2011
Hello :)

1. You should use the IP address that will be used for sending email. You can use the "Email Authentication" option in cPanel to generate the correct SPF record for you. EX:

v=spf1 +a +mx +ip4: ?all
2. You can check to see if RDNS has been configured for an IP address with the "host" command. EX:

3. The following option is available under the "ACL Options" tab in "WHM Home » Service Configuration » Exim Configuration Manager":

"Reject SPF failures"

This option will ensure mail is rejected at SMTP time if the sender fails SPF checks.

Thank you.