smtpd_client_restrictions = 
        permit_mynetworks
        sleep 1 
        reject_unauth_pipelining 
    smtpd_delay_reject = no
    smtpd_helo_required = yes
    smtpd_helo_restrictions =
        permit_mynetworks
        reject_non_fqdn_helo_hostname,
        reject_invalid_helo_hostname,
        permit
    smtpd_sender_restrictions =
        permit_mynetworks
        reject_non_fqdn_sender
        reject_unknown_sender_domain
        permit
    smtpd_recipient_restrictions =
        reject_unauth_pipelining,
       reject_non_fqdn_recipient,
       reject_unknown_recipient_domain,
       permit_mynetworks,
       reject_unauth_destination,
       check_sender_access hash:/etc/postfix/sender_access,
       reject_rbl_client zen.spamhaus.org,
       reject_rbl_client bl.spamcop.net,
       check_policy_service unix:postgrey/socket,
       permit