Find number of servers where something is true

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1

Hi, I’m trying to get a count of how many servers have a specific file on them. For example, if /tmp/testFile is on 8 of 25 hosts that I’m running a playbook against, I’d like to register a variable and give it the value of 8. Is this possible?

2

http://docs.ansible.com/ansible/group_by_module.html

will let you make a group by fact, you could then just have a task
on localhost output '{{ groups["has_that_file"] _ length }}".

There's a set_fact task you can use to set a (boolean) fact on hosts,
or just bite the bullet and write a custom fact.

It seems a bit of an odd requirement to be honest, that's the best I can
suggest from what you've posted.

3

sorry that should be:

{{ groups["has_that_file"] | length }}

4

This can also be accomplished using the stat module, and then a little jinja2 pipeline:

  • hosts: all
    tasks:

  • stat:
    path: /tmp
    register: stat_result

  • debug:
    msg: “{{ hostvars|dictsort|selectattr(‘1.stat_result.stat.exists’)|list|length }}”
    run_once: true

This would output something like the following for me:

TASK [debug] *********************************************************************************************************************************************************************
ok: [example.org] => {
“msg”: “8”
}