...

# Django : 2014-02-10
# default: $inet_socket_port = 10024;
#$inet_socket_port = 10024;   # listen on this local TCP port(s)
$inet_socket_port = [10024,10026];  # listen on multiple TCP ports

...

# it is up to MTA to re-route mail from authenticated roaming users or
# from internal hosts to a dedicated TCP port (such as 10026) for filtering
$interface_policy{'10026'} = 'ORIGINATING';

$policy_bank{'ORIGINATING'} = {  # mail supposedly originating from our users
  originating => 1,  # declare that mail was submitted by our smtp client
  allow_disclaimers => 1,  # enables disclaimer insertion if available
  # notify administrator of locally originating malware
  virus_admin_maps => ["virusalert\@$mydomain"],
  spam_admin_maps  => ["virusalert\@$mydomain"],
  warnbadhsender   => 1,
  # forward to a smtpd service providing DKIM signing service
  #forward_method => 'smtp:[127.0.0.1]:10027',
  # force MTA conversion to 7-bit (e.g. before DKIM signing)
  smtpd_discard_ehlo_keywords => ['8BITMIME'],
  bypass_banned_checks_maps => [1],  # allow sending any file names and types
  terminate_dsn_on_notify_success => 0,  # don't remove NOTIFY=SUCCESS option
};

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