Domain Key O
The o tag denotes the outbound signing policy.
Domain key o. Create your domain s key pair a private key and a corresponding public key with the dknewkey command. Domainkeys dkim combines of a public key cryptography and a dns to provide credible domain level authentication for email. The sending domain policy is published using a dns txt record as follows.
The t y value pair means that the domain is using this key in test mode. If your domain is hosted by windows dns server in local lan. Deploy public key by dkim manager.
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