Greylisting is recommended for advanced users only. See here for more information.
Enable or disable server wide greylisting. Greylisting will tell the mail server to temporarily reject any email from a sender it does not recognize. If the mail is legitimate, the originating server will try again after a delay, and if sufficient time has elapsed, the email will be accepted.
Greylisting interval -
A period of time that a sender should wait for before retrying sending the mail (in minutes).
Expire interval -
A period of time after which a record in grey list expires (in minutes). The default expire interval is 36 days.
Enable or disable penalties. Penalties are a period of time added to the grey interval in case a sender retried sending mail before the grey interval finished (in minutes).
Penalty interval -
A period of time added to the grey interval in case a sender retried sending mail before the grey interval finished (in minutes).
Whitelist a mail server from greylisting. Remember that you are whitelisting the remote hosts client rDNS record (PTR record) not an email address. Wildcard patterns are supported:
// whitelist a single mail server mail.example.com // whitelist all mail servers from a provider *.example.com
Blacklist a mail server from greylisting. Emails that are blacklisted will be listed under Warden -> Logs -> Reject Log. Blacklisted entries will have the a
451 4.7.1 status with the message
// matches mta-70-12-15.sparkpostmail.com *[0-9][0-9]-[0-9][0-9]-[0-9][0-9]* // matches any of the following keywords in the remote host like mail25.static.mailgun.info dynamic|static|ppp|dyn-ip|dial-up