Idempotence and Random Variables in Ansible

Question

Is there a way to guarantee idempotence for playbooks that use randomly generated variables?

For example, I want to setup my crontabs to trigger emails on multiple serve

Answer 1

Instead of a random value, you could get something related to the node, like an hash of the hostname or the last byte of the ip address.

This is an example:

- name: Get a pseudo-random minute 
  shell: expr $((16#`echo "{{inventory_hostname}}" | md5sum | cut -c 1-4`)) % 30
  register: minute
  changed_when: false