Ansible: Using ansible facts, how can I get a disk device based on the storage controller value and then set the device as a variable

comet003 picture comet003 · Dec 30, 2017 · Viewed 13k times · Source

Context: I have a system that has a combination of disks from different storage controllers, so each type of disk has different purpose. I'm new to ansible and learning as I go. Writing a playbook that gets the disk from each type of controller so I can set them up.

Ex. Below is sample output from #'filter=ansible_devices*' ... sdz device is from SATA controller. On my other hosts it might not always be sdz.. so I want to get the device name and store in a variable if in the facts the device has "host": "SATA controller". I'm thinking maybe I need to traverse through ansible_devices dictionaries, find the key that matches ("host": "SATA controller") and then get the parent dict for it which would be the device. Is there a way to do that.. or easier way? :)

"sdz": {
            "holders": [
                "mpathz"
            ],
            "host": "SATA controller: Intel Corporation C610/X99 series chipset 6-Port SATA Controller [AHCI mode] (rev 05)",
            "links": {
                "ids": [
                    "ata-SAMSUNG_MZ7GE960HMHP-00003_S1Y2NYAFC02269",
                    "wwn-0x50025388003aeb2a"
                ],
                "labels": [],
                "masters": [
                    "dm-19"
                ],
                "uuids": []
            },
            "model": "SAMSUNG MZ7GE960",
            "partitions": {},
            "removable": "0",
            "rotational": "0",
            "sas_address": null,
            "sas_device_handle": null,
            "scheduler_mode": "cfq",
            "sectors": "1875385008",
            "sectorsize": "512",
            "serial": "S1Y2NYAFC02269",
            "size": "894.25 GB",
            "support_discard": "512",
            "vendor": "ATA",
            "virtual": 1,
            "wwn": "0x50025388003aeb2a"

Answer

Rob H picture Rob H · Dec 31, 2017

This tasks fragment in a playbook should do it, assuming ansible_devices is already set as a variable

 tasks:

    - name: get device name
      set_fact:
        device_name: "{{ item.key }}"
      no_log: True
      with_dict: "{{ ansible_devices }}"
      when: "item.value.host.startswith('SATA')"

    - name: show all values for selected device name
      debug: var=ansible_devices[device_name]

    - name: show only device name
      debug: var=device_name

The set_fact will get your device name. The two debug statements will dump all of the device values and just the device name, respectively.