dev-allocate-storage.yaml

---
- name: allocate storage
  hosts:
    - ansible1.example.com
    - ansible2.example.com
    - ansible3.example.com
  vars:
    - disk_name: sdb
    - partition_number: 1
    - vg_name: vgdata
    - lv_name: lvdata
    - disk_gb_threshold: 1
    - disk_bytes_threshold: "{{ disk_gb_threshold * 1024 * 1024 * 1024 }}"
    - large_lv_size: 1500M
    - small_lv_size: 800M
    - disk_bytes: "{{ lsblk.stdout }}"
  tasks:

    - name: abort if second disk does not exist
      assert:
        that:
          - "ansible_facts['devices']['{{ disk_name }}'] is defined"
        fail_msg: "no second hard disk"

    - name: get disk size
      command:
        cmd: /bin/lsblk -n -d -o SIZE -b /dev/{{ disk_name }}
      changed_when: false
      register: lsblk

    - name: partition disk
      parted:
        device: "/dev/{{ disk_name }}"
        state: present
        number: "{{ partition_number }}"

    - name: create volume group
      lvg:
        vg: "{{ vg_name }}"
        pvs: "/dev/{{ disk_name }}{{ partition_number }}"

    - name: create large logical volume
      lvol:
        vg: "{{ vg_name }}"
        lv: "{{ lv_name }}"
        size: "{{ large_lv_size }}"
      when: disk_bytes > disk_bytes_threshold

    - name: handle case of small disk
      block:
        - name: create small logical volume
          lvol:
            vg: "{{ vg_name }}"
            lv: "{{ lv_name }}"
            size: "{{ small_lv_size }}"
        - name: notify user if a small disk was found
          debug:
            msg: "small disk found"
      when: disk_bytes <= disk_bytes_threshold

    - name: create filesystem
      filesystem:
        dev: "/dev/{{ vg_name }}/{{ lv_name }}"
        fstype: xfs
...