zimbra enforce SPF checking for incomming email

In this tutorial, I'm enable and configure spf to check for incommning email with cbpolicyd. By default, the SPF checking module is not enable and there are no SPF policies. zimbra logs with "Sender address rejected: Failed SPF check". How to zimbra enforce spf checking for incomming email as below. I'm running commands as zimbra account ( su - zimbra ) Links to below you maybe likes: zimbra 8.6 cbpolicyd example How to install and configure zimbra multi server. How to restrict to user sending mail on zimbra 8.6. How to Restrict Sending to Distribution list in zimbra mail. How to change last login time for all accounts in zimbra ldap. How to zimbra reject authenticated sender login mismatch. To check zimbra policyd spf $ zmprov gs `zmhostname` zimbraCBPolicydCheckSPFEnabled If zimbra spf checking not enable then, to enable policyd checkspf $ zmprov ms `zmhostname` zimbraCBPolicydCheckSPFEnabled TRUE To restart policyd service $ zmcbpolicydctl resta