DKIM Zimbra 8.6

DKIM is an email authentication method designed to detect email spoofing, for more detail : Wiki DKIM

Make sure your DKIM has been enabled in your zimbra.

su - zimbra
/opt/zimbra/libexec/zmdkimkeyutil -a -d domain.com
148ERADC-FCE5-11E6-AF44-005A1B26B745._domainkey	IN	TXT	( "v=DKIM1; k=rsa; "	  "p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDg2uVLIssdfsfgu62+c7n0sxugzm8Lpr4A7o7veL4kIeifat2hD53P2KKQTV978HxBTQKrEFByLbG0WZuNracNJU9L5NOKtmYnE7ksxF9ODMKqFK+ltsmM9qkVxbU3xQOVdufDlV2Zk8Ya0WMkYWzKgWIwIDAQAB" )  ; ----- DKIM key 148ERADC-FCE5-11E6-AF44-005A1B26B745 for domain.com

Add DNS TXT record:

148ERADC-FCE5-11E6-AF44-005A1B26B745._domainkey IN TXT v=DKIM1; k=rsa;p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDg2uVLIssdfsfgu62+c7n0sxugzm8Lpr4A7o7veL4kIeifat2hD53P2KKQTV978HxBTQKrEFByLbG0WZuNracNJU9L5NOKtmYnE7ksxF9ODMKqFK+ltsmM9qkVxbU3xQOVdufDlV2Zk8Ya0WMkYWzKgWIwIDAQAB

Test DKIM signature by sending email using this website: http://dkimvalidator.com/

DKIM Validator