Mundy

IT Knowledge Base

User Tools

Site Tools


Sidebar

Contact me at dan@mundy.co for any feedback or suggestions.


My other sites:

Search all my sites:

spf

SPF

Tools

  • SPF Test - SPF Verify - SPF Validator - this gives you a one-time email address to send a test mail to, they wait for your email and then show whether it passed SPF test, reverse DNS, RBL, etc. Works well

Notes

example.com.au.      IN TXT     "v=spf1 mx ip4:1.1.1.1/32 include:spf.protection.outlook.com ~all"

the "mx" means that any IP addresses listed in the MX records are allowed to send email
the "ip4:1.1.1.1/32" is an IP address or block of addresses that can send, e.g. your local SMTP relay
the "include:spf.protection.outlook.com" means that Office 365 domain can send email
the "~all" means it's a soft fail. If you had made it a hard fail, using "-all", you'll probably get clients that can't send to some domains
Statement Result Meaning
+all pass Allow all mail
-all fail Only allow mail that matches one of the parameters (IPv4, MX, etc) in the record
~all softfail Allow mail whether or not it matches the parameters in the record
?all neutral No policy statement

Some examples of valid SPF records:

calibreone.com.au	text = "v=spf1 mx include:spf.myconnectwise.net include:spf.protection.outlook.com ~all"

microsoft.com	text = "v=spf1 include:_spf-a.microsoft.com include:_spf-b.microsoft.com include:_spf-c.microsoft.com include:_spf-ssg-a.microsoft.com include:spf-a.hotmail.com ip4:147.243.128.24 ip4:147.243.128.26 ip4:147.243.1.153 ip4:147.243.1.47 ip4:147.243.1.48 -all"

hotmail.com	text = "v=spf1 include:spf-a.outlook.com include:spf-b.outlook.com ip4:157.55.9.128/25 include:spf.protection.outlook.com include:spf-a.hotmail.com include:_spf-ssg-b.microsoft.com include:_spf-ssg-c.microsoft.com ~all"

Example with multiple approved IP addresses:
<code>ato.gov.au	text = "v=spf1 ip4:180.149.192.213 ip4:180.149.192.214 ip4:180.149.192.215 ip4:180.149.192.216 ip4:180.149.192.242 mx include:sge.net -all"
spf.txt · Last modified: 2018/04/09 09:56 (external edit)