Fix SMTP connection delay when peer hostname cannot be resolved

site-cookbooks/kosmos_email/recipes/postfix.rb

@@ -27,6 +27,7 @@ node.normal['postfix']['main']['mynetworks'] = ["10.1.1.0/24", "127.0.0.0/8"]
 node.normal['postfix']['main']['smtpd_use_tls'] = "yes"
 node.normal['postfix']['main']['smtpd_tls_cert_file'] = "/etc/letsencrypt/live/#{hostname}/fullchain.pem"
 node.normal['postfix']['main']['smtpd_tls_key_file'] = "/etc/letsencrypt/live/#{hostname}/privkey.pem"
+node.normal['postfix']['main']['smtpd_peername_lookup'] = "no"
 node.normal['postfix']['main']['mailbox_transport'] = "lmtp:unix:private/dovecot-lmtp"
 node.normal['postfix']['main']['virtual_transport'] = "lmtp:unix:private/dovecot-lmtp"
 node.normal['postfix']['main']['smtputf8_enable'] = "no"
@@ -78,6 +79,7 @@ node.normal['postfix']['master'] = {
       "-o syslog_name=postfix/10465",
       "-o smtpd_tls_wrappermode=yes",
       "-o smtpd_sasl_auth_enable=yes",
+      "-o smtpd_relay_restrictions=permit_sasl_authenticated,reject",
       "-o smtpd_recipient_restrictions=permit_mynetworks,permit_sasl_authenticated,reject",
       "-o smtpd_sasl_type=dovecot",
       "-o smtpd_sasl_path=private/auth",