How to do something with nested variables...

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1

Hi AnsiPeeps,

I have a nested structure in vars as so:

data_bricks:
ovirt-node-01:

  • gluster_brick2
  • gluster_brick4
    ovirt-node-02:
  • gluster_brick1
  • gluster_brick3
    ovirt-node-03:
  • gluster_brick2
  • gluster_brick4

(the number of items in the 2nd-level node now is two, but may be higher if necessary…)

So in the associated playbook, I need to do something akin to:

“mkdir -p /{{ item }}/data_brick”

For each item under the second-level item, which happens to be the {{ ansible_hostname }} of the server that I need the commands to be run on - so for instance on “ovirt-node-01” I’d need to run the commands:
“mkdir -p /gluster_brick2/data_brick”

“mkdir -p /gluster_brick4/data_brick”

In the playbook I want to use the above in, I have written a test debug task as so:

  • name: Figure out how to use nested vars
    debug: msg=“brick name is {{ item }}”
    with_subelements:
  • engine_bricks.{{ ansible_hostname }}
    tags: tryme

Which must be horribly wrong, because when I run it against the group of servers having the server names on the second level of the nested vars, it blows up with this error:

TASK: [ist-ovirt-gluster | Figure out how to use nested vars] *****************
fatal: [ovirt-node-02] => subelements lookup expects a list of two items, first a dict or a list, and second a string
fatal: [ovirt-node-01] => subelements lookup expects a list of two items, first a dict or a list, and second a string
fatal: [ovirt-node-03] => subelements lookup expects a list of two items, first a dict or a list, and second a string

I’ve read over http://docs.ansible.com/ansible/playbooks_loops.html a few times, thought i’d want “with_subelements”, but maybe not? Can anyone give me a pointer how to achieve what I’m trying to do?

TIA,
Will

2

Never mind all this, thought about it some more and will handle it with a two-level structure (i.e. a list var) in host_vars