create_nspawn_container.yml

# ansible-playbook -e "machine_name=foo suite=bar ip_address=baz ip_gateway=zab" create_nspawn_container.yml
---
- hosts: nspawn_host
  become: yes
  vars:
    suite: stable
    machine_name: test
    mirror: http://ftp.gr.debian.org/debian
    ip_address: 192.168.1.100/24
    ip_gateway: 192.168.1.1

  tasks:
  - name: debootstrap new machine
    command: debootstrap {{ suite }} {{ machine_name }} {{ mirror }}
    args:
      chdir: /var/lib/machines
      creates: /var/lib/machines/{{ machine_name }}

  - name: disable ifupdown inside the new machine
    file:
      name: "{{ item }}"
      state: absent
    with_items:
      - /var/lib/machines/{{ machine_name }}/etc/systemd/system/multi-user.target.wants/networking.service
      - /var/lib/machines/{{ machine_name }}/etc/systemd/system/network-online.target.wants/networking.service
    tags:
      - networking

  - name: enable networkd and resolved
    file:
      name: /var/lib/machines/{{ machine_name }}/etc/systemd/system/multi-user.target.wants/{{ item }}
      state: link
      src: /lib/systemd/system/{{ item }}
      force: yes
    with_items:
      - systemd-networkd.service
      - systemd-resolved.service
    tags:
      - networking
  
  - name: write network file
    copy:
      content: |
        [Match]
        Name=host0

        [Network]
        Address={{ ip_address }}
        Gateway={{ ip_gateway }}
      dest: /var/lib/machines/{{ machine_name }}/etc/systemd/network/01-host0.network
    tags:
      - networking

  - name: temporarily change resolv.conf in new machine
    copy:
      content: "nameserver 8.8.8.8"
      dest: /var/lib/machines/{{ machine_name }}/etc/resolv.conf
    tags:
      - complete_installation
  
  - name: install misc packages
    command: systemd-nspawn -UD {{ machine_name }} apt-get -y install {{ item }}
    args:
      chdir: /var/lib/machines
    with_items:
      - dbus
    tags:
      - complete_installation

  - name: ln resolv.conf
    file:
      name: /var/lib/machines/{{ machine_name }}/etc/resolv.conf
      state: link
      src: /run/systemd/resolve/resolv.conf
      force: yes
    tags:
      - networking

  - name: create host .nspawn file
    copy:
      content: |
        [Exec]
        Boot=on

        [Network]
        VirtualEthernet=on
      dest: /etc/systemd/nspawn/{{ machine_name }}.nspawn

  - name: Start new container (enable)
    systemd:
      daemon_reload: yes
      name: systemd-nspawn@{{ machine_name }}
      enabled: yes
      state: started
    delay: 4

  - name: change hostname
    command: hostnamectl --machine="{{ machine_name }}" set-hostname "{{ machine_name }}"