Remove a /dev/md0 root from a running system

remove-md.yml

- hosts: all

  vars:
    root_device: "/dev/sda2"

  tasks:

    - name: Install apt packages
      apt:
        name:
          - debootstrap
        state: present

    - name: Fail and remove {{ root_device }} from the RAID5 set
      shell: |
        mdadm --fail /dev/md0 {{ root_device }}
        mdadm --remove /dev/md0 {{ root_device }}

    - name: format new root
      community.general.filesystem:
        fstype: ext4
        dev: "{{ root_device }}"
        force: true

    - name: Find UUID of {{ root_device }}
      shell: blkid -s UUID -o value {{ root_device }}
      register: blkid

    - name: Set a fact based upon the output
      set_fact:
        blkid: "{{ blkid.stdout_lines[0] }}"

    - name: Temporary mount of the new root drive
      shell: mount {{ root_device }} /mnt

    - name: Install the system
      shell: debootstrap noble /mnt

    - name: Ensure directory exists
      ansible.builtin.file:
        path: /mnt/boot/efi
        state: directory

    - name: Copy files from original root
      shell: rsync -a {{ item }} /mnt{{ item }}
      with_items:
        - /etc/hostname
        - /etc/hosts
        - /etc/fstab
        - /etc/passwd
        - /etc/shadow
        - /etc/group
        - /etc/default/grub
        - /etc/sudoers.d/
        - /etc/ssh/
        - /etc/netplan/
        - /etc/apt/
        - /root/
        - /home/

    - name: Update the new /etc/fstab
      ansible.builtin.lineinfile:
        path: /mnt/etc/fstab
        regexp: '/dev/[^ ]* / ext4 defaults'
        line: "/dev/disk/by-uuid/{{ blkid }} / ext4 defaults 0 1"
        owner: root
        group: root
        mode: '0644'

    - name: Temporary mount from the live environment
      shell: |
        mount --make-private --rbind /dev  /mnt/dev
        mount --make-private --rbind /proc /mnt/proc
        mount --make-private --rbind /sys  /mnt/sys
        mount /dev/sda1 /mnt/boot/efi

    - name: Run apt update
      shell: chroot /mnt apt update

    - name: Install grub
      shell: chroot /mnt apt install -y grub-efi-amd64 grub-efi-amd64-signed \
        linux-image-generic shim-signed

    - name: Install SSHD
      shell: chroot /mnt apt install -y openssh-server

    - name: Update grub
      shell: chroot /mnt update-grub

    - name: Install GRUB
      shell: |
        chroot /mnt grub-install --target=x86_64-efi --efi-directory=/boot/efi \
          --bootloader-id=ubuntu --recheck --no-floppy

    - name: Reboot
      shell: |
        reboot