LVM local loopback device setup (RedHat)

lvm-loopback-1.yml

- hosts: localhost
  connection: local
  gather_facts: yes
  vars:
    volume_path: "/var/lib/lvm-volume1"
    volume_size: "100M"
    volume_name: "loopback-volumes"
  tasks:
    - name: Ensure LVM dependencies are installed
      package:
        name: lvm2
        state: present

    - name: Create LVM volume file
      command: >-
        dd if=/dev/zero of={{ volume_path }} bs=1 count=0 seek={{ volume_size }}
      args:
        creates: "{{ volume_path }}"

    - name: Check for existing LVM loopback device
      shell: >-
        losetup -j {{ volume_path }} -l -O NAME | tail -n-1
      changed_when: false
      register: _existing_loopback_device

    - name: Create LVM loopback device
      command: >-
        losetup -f {{ volume_path }} --show
      register: _new_loopback_device
      when:
        - _existing_loopback_device.stdout == ""

    - name: Set loopback device path
      set_fact:
        _lvm_dev_path: "{{ _new_loopback_device.stdout | default(_existing_loopback_device.stdout, True) }}"

    - name: Create LVM volume group
      lvg:
        vg: "{{ volume_name }}"
        pvs: "{{ _lvm_dev_path }}"
        state: present

    - name: Create service to run losetup for LVM on startup
      copy:
        dest: "/etc/systemd/system/lvm-{{ volume_name }}-losetup.service"
        content: |
          [Unit]
          Description=LVM {{ volume_name }} loopback device setup

          DefaultDependencies=no
          Conflicts=umount.target
          Requires=lvm2-lvmetad.service systemd-udev-settle.service
          Before=local-fs.target umount.target
          After=lvm2-lvmetad.service systemd-udev-settle.service

          [Service]
          Type=oneshot
          ExecStart=/sbin/losetup {{ _lvm_dev_path }} {{ volume_path }}
          ExecStop=/sbin/losetup -d {{ _lvm_dev_path }}
          RemainAfterExit=yes

          [Install]
          WantedBy=local-fs-pre.target

    - name: Create service to run loopback device filesystem checks
      copy:
        dest: "/etc/systemd/system/lvm-{{ volume_name }}-fsck.service"
        content: |
          [Unit]
          Description=LVM {{ volume_name }} filesystem check

          DefaultDependencies=no
          Conflicts=umount.target
          Requires=lvm-{{ volume_name }}-losetup.service
          Before=local-fs.target umount.target
          After=lvm-{{ volume_name }}-losetup.service

          [Service]
          Type=oneshot
          ExecStart=/sbin/fsck -pfv {{ _lvm_dev_path }}

          [Install]
          WantedBy=local-fs-pre.target

    - name: Enable the LVM losetup service
      systemd:
        name: "{{ item }}"
        enabled: yes
        daemon_reload: yes
      loop:
        - "lvm-{{ volume_name }}-losetup"
        - "lvm-{{ volume_name }}-fsck"

lvm-loopback-2.yml

- hosts: localhost
  connection: local
  gather_facts: yes
  vars:
    volume_path: "/var/lib/lvm-volume1"
    volume_size: "100M"
    volume_name: "loopback-volumes"
  tasks:
    - name: Ensure LVM dependencies are installed
      package:
        name: lvm2
        state: present

    - name: Create LVM volume file
      command: >-
        dd if=/dev/zero of={{ volume_path }} bs=1 count=0 seek={{ volume_size }}
      args:
        creates: "{{ volume_path }}"

    - name: Create or get LVM loopback device
      shell: |-
        exit_code=0
        existing_device=$(losetup -j {{ volume_path }} -l -O NAME | tail -n-1)
        if [[ -z "${existing_device}" ]]; then
            losetup -f {{ volume_path }} --show
            exit_code=2
        else
            echo ${existing_device}
        fi
        exit ${exit_code}
      args:
        executable: /bin/bash
      register: _loopback_device
      changed_when: _loopback_device.rc == 2
      failed_when: _loopback_device.rc not in [0,2]

    - name: Create LVM volume group
      lvg:
        vg: "{{ volume_name }}"
        pvs: "{{ _loopback_device.stdout }}"
        state: present

    - name: Create service to run losetup for LVM on startup
      copy:
        dest: "/etc/systemd/system/lvm-{{ volume_name }}-losetup.service"
        content: |
          [Unit]
          Description=LVM {{ volume_name }} loopback device setup

          DefaultDependencies=no
          Conflicts=umount.target
          Requires=lvm2-lvmetad.service systemd-udev-settle.service
          Before=local-fs.target umount.target
          After=lvm2-lvmetad.service systemd-udev-settle.service

          [Service]
          Type=oneshot
          ExecStart=/sbin/losetup {{ _loopback_device.stdout }} {{ volume_path }}
          ExecStop=/sbin/losetup -d {{ _loopback_device.stdout }}
          RemainAfterExit=yes

          [Install]
          WantedBy=local-fs-pre.target

    - name: Create service to run loopback device filesystem checks
      copy:
        dest: "/etc/systemd/system/lvm-{{ volume_name }}-fsck.service"
        content: |
          [Unit]
          Description=LVM {{ volume_name }} filesystem check

          DefaultDependencies=no
          Conflicts=umount.target
          Requires=lvm-{{ volume_name }}-losetup.service
          Before=local-fs.target umount.target
          After=lvm-{{ volume_name }}-losetup.service

          [Service]
          Type=oneshot
          ExecStart=/sbin/fsck -pfv {{ _loopback_device.stdout }}

          [Install]
          WantedBy=local-fs-pre.target

    - name: Enable the LVM losetup service
      systemd:
        name: "{{ item }}"
        enabled: yes
        daemon_reload: yes
      loop:
        - "lvm-{{ volume_name }}-losetup"
        - "lvm-{{ volume_name }}-fsck"