/^\s*localhost\s*$/                             REJECT  Invalid HELO hostname specified
/^\s*localhost\.localdomain\s*$/                REJECT  Invalid HELO hostname specified
/^\s*127\.([0-9]{1,3}\.){2}[0-9]{1,3}\s*$/      REJECT  Invalid HELO hostname specified
/^\s*10\.([0-9]{1,3}\.){2}[0-9]{1,3}\s*$/       REJECT  Invalid HELO hostname specified
/^\s*192\.168.[0-9]{1,3}\.[0-9]{1,3}\s*$/       REJECT  Invalid HELO hostname specified
/^\s*172\.((1[6-9]\.)|(2[0-9]\.)|(3[0-1]\.))([0-9]{1,3}\.)[0-9]{1,3}\s*$/   REJECT  Invalid HELO hostname specified

{% for host in groups['nodes'] -%}
/^\s*{{ hostvars[host]['external_ipv4'] | regex_escape() }}\s*$/	REJECT  Invalid HELO hostname specified
{% endfor -%}

{% for domain in mail_server.domains -%}
/(^|\.){{ domain | regex_escape() }}\s*$/	REJECT  Invalid HELO hostname specified
{% endfor -%}