- name: Retrieve IPv4 addresses of SMTP relay host

  shell: "getent ahostsv4 '{{ smtp_relay_host }}' | awk '{ print $1 }' | sort -u"  # noqa 306

  # [306] Shells that use pipes should set the pipefail option

  #   The getent ahostsv4 command has non-zero exit code if the

  #   supplies name cannot be resolved. However, that is a valid

  #   use-case for extracting this information. It effectively means

  #   that no IPv4 firewall rules will be deployed for allowing

  #   incoming connections from the SMTP relay host.

  changed_when: false

  register: smtp_relay_host_ipv4

- name: Retrieve IPv6 addresses of SMTP relay host

  shell: "getent ahostsv6 '{{ smtp_relay_host }}' | awk '{ print $1 }' | grep -v '^::ffff:' | sort -u"  # noqa 306

  # [306] Shells that use pipes should set the pipefail option

  #   The getent ahostsv6 command has non-zero exit code if the

  #   supplies name cannot be resolved. However, that is a valid

  #   use-case for extracting this information. It effectively means

  #   that no IPv6 firewall rules will be deployed for allowing

  #   incoming connections from the SMTP relay host.

  changed_when: false

  register: smtp_relay_host_ipv6

- name: Normalise the SMTP relay host IPv4 addresses variable

  set_fact:

    smtp_relay_host_ipv4: "{{ smtp_relay_host_ipv4.stdout_lines | reject('equalto', '') | list }}"

  when: "smtp_relay_host | length != 0"

- name: Normalise the SMTP relay host IPv6 addresses variable

  set_fact:

    smtp_relay_host_ipv6: "{{ smtp_relay_host_ipv6.stdout_lines | reject('equalto', '') | list }}"

  when: "smtp_relay_host | length != 0"