Zim's Notes

Just work related notes.

Waiting for Resources in Ansible

Some resources may be not in a desired state after running a playbook. Especially when using Azure REST API, resource may be in Creating or Provisioning state. Sometimes it’s necessary to wait unll provisioning state becomes Succeeded.

The best way to do this is to use facts module to periodically query the resource and exit the loop when desired state is achieved. Here’s how to do it.

After the task that creates your virtual machine (or later), put following tasks. Actually only Wait for Virtual Machine to be ready is essential here. All the other tasks are just for demo purposes.

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- name: Get VM facts
  azure_rm_resource_facts:
    api_version: '2018-10-01'
    resource_group: ''
    provider: Compute
    resource_type: virtualMachines
    resource_name: ""
  register: output

- debug:
    var: output.response[0].properties.provisioningState

- name: Wait for Virtual Machine to be ready
  azure_rm_resource_facts:
    api_version: '2018-10-01'
    resource_group: ''
    provider: Compute
    resource_type: virtualMachines
    resource_name: ""
  register: output
  until: output.response[0].properties.provisioningState == 'Succeeded'
  delay: 60
  retries: 5

- debug:
    var: output.response[0].properties.provisioningState

You should see following output:

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TASK [Create a vm with password authentication.] *******************************************
changed: [localhost]

TASK [Get VM facts] ************************************************************************
ok: [localhost]

TASK [debug] ******************************************************************************
ok: [localhost] => {
    "output.response[0].properties.provisioningState": "Creating"
}

TASK [Wait for Virtual Machine to be ready] *****************************************************
FAILED - RETRYING: Wait for Virtual Machine to be ready (5 retries left).
FAILED - RETRYING: Wait for Virtual Machine to be ready (4 retries left).
ok: [localhost]

TASK [debug] ******************************************************************************
ok: [localhost] => {
    "output.response[0].properties.provisioningState": "Succeeded"
}

PLAY RECAP ********************************************************************************
localhost                  : ok=18   changed=1    unreachable=0    failed=0    skipped=0

References:

Ansible documentation on do-until loops: https://docs.ansible.com/ansible/latest/user_guide/playbooks_loops.html#do-until-loops