Ansible play to expand disk and upgrade Ubuntu

update_os.yml

- block:
  - name: Upgrade OS to latest LTS release
    shell: |
      test $(lsb_release -si) = Ubuntu || exit 0
      parted /dev/sda unit s print | awk '
        /^Disk \// {
          total = substr($3,0,length($3)-1)
        }
        $5 == "extended" {
          xpnum = $1
          xsectors = substr($3,0,length($3)-1)
        }
        $5 == "logical" {
          lpnum = $1
          lsectors = substr($3,0,length($3)-1)
        }
        END {
          if (lsectors > 1 && lsectors < total - 1) {
            printf "resizepart %s %ss\n", xpnum, total - 1
            printf "resizepart %s %ss\n", lpnum, total - 1
          }
        }' | xargs parted --script /dev/sda
      pvresize /dev/sda5
      lvresize /dev/ubuntu-vg/root -l '+100%FREE'
      resize2fs /dev/ubuntu-vg/root
      export DEBIAN_FRONTEND=noninteractive
      apt-get update
      apt-get upgrade -q -y -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confold" --with-new-pkgs
      apt-get autoremove -y
      do-release-upgrade -f DistUpgradeViewNonInteractive
      systemctl reboot
    vars:
      ansible_host: "{{ vm_ipaddress }}"
    become: True
  
  - name: Wait for reboot after OS upgrade
    wait_for:
      port: "{{ ansible_port | default('22') }}"
      host: "{{ vm_ipaddress }}"
    connection: local
    become: no

  when:
    - nutanix.created is defined and nutanix.created
    - "'linux' in group_names"
    - not ansible_check_mode

This play gets run straight after provisioning a VM in Nutanix*. Typically I would run the full Ansible playbook then go back to upgrade the OS interactively but this play does the upgrade for me automatically.

Nutanix provisions a VM from a disk image clone of a minimal Ubuntu installation but with an expanded size.

This play

1. expands the MBR partition table's extended partition (usually sda2)
2. expands the logical volume (sda5) within the extended volume
3. resizes the LVM Physical Volume to cover the expanded logical volume
4. expands the LVM Logical Volume for the root filesystem
5. resizes the Ext4 root filesytem
6. updates the Ubuntu package repos
7. upgrades installed packages on current release
8. upgrades Ubuntu to the latest LTS release

all before knowing anything about the VM except it's IP address.

Pros

• gets run before Ansible has gathered any facts or modified any configs
• ensures I'm left with a fully updated and configured VM

Cons

• it’s very opinionated about how the disks are laid out and named - will only work on Ubuntu
• it assumes you always want the latest LTS release and maybe not all roles can support that version yet
• it adds about 15 minutes to creating a new linux VM

* (actually there is a step in between to set the vm_ipaddress fact)