Email Security

• SFP, DMARC and DKIM - tool - Reference: https://binsec.nl/powershell-script-for-spf-dmarc-and-dkim-validation/
  • Install Powershell script -

    Install-Module DomainHealthChecker

  • Run the command -

    Invoke-SpfDkimDmarc -Name <domain>

https://www.cloudflare.com/learning/dns/dns-records/dns-spf-record/

Example - DNS TXT record for orourke.tv is the below - which includes the SMTP IP address for smtp.reg365.net

v=spf1 ip4:85.233.160.17 –all

HOwever above isn't very good - as it only has a single IP address - and what if IP address changes - hence this is a better config:

v=spf1 include:spf.reg365.net ~all

use '~all' instead a soft fail, instead of '-all' for a hard fail.

Here is another example:

v=spf1 include:_spf.google.com –all