volume_size parameter ignored in ec2 module

Hey Folks,
I’ve been banging my head against this for a few days with no luck. I’m trying to change the size of my default disk (/dev/xvda1) when spinning up new ec2 boxes with Ansible. I have the following:

`

  • name: provision new boxes

hosts: localhost

gather_facts: False

tasks:

  • name: Provision a set of instances

ec2:

group: “{{ aws_security_group }}”

instance_type: “{{ aws_instance_type }}”

image: “{{ aws_ami_id }}”

region: “{{ aws_region }}”

vpc_subnet_id: “{{ aws_vpc_subnet_id }}”

key_name: “{{ aws_key_name }}”

wait: true

count: “{{ num_machines }}”

instance_tags: “{{ tags }}”

volumes:

  • device_name: /dev/sda1

volume_size: 15
register: ec2
`

Which should set my root device size to 15g. Instead, it just gets ignored and the root device is set to the default 8. What am I doing wrong?