Loop over facts in playbook

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1

Hi

I have some troubles to understand how to loop over facts in playbook. Suppose I have the following:

ansible node01 -m setup -a 'filter=ansible_devices' SSH password: SU password[defaults to SSH password]: node01 | success >> { "ansible_facts": { "ansible_devices": { "sda": { "holders": [], "host": "Serial Attached SCSI controller: VMware PVSCSI SCSI Controller (rev 02)", "model": "Virtual disk", "partitions": { "sda1": { "sectors": "204800", "sectorsize": 512, "size": "100.00 MB", "start": "2048" }, "sda2": { "sectors": "104650752", "sectorsize": 512, "size": "49.90 GB", "start": "206848" } }, "removable": "0", "rotational": "1", "scheduler_mode": "noop", "sectors": "104857600", "sectorsize": "512", "size": "50.00 GB", "support_discard": "0", "vendor": "VMware" }, "sdb": { "holders": [], "host": "Serial Attached SCSI controller: VMware PVSCSI SCSI Controller (rev 02)", "model": "Virtual disk", "partitions": { "sdb1": { "sectors": "10469376", "sectorsize": 512, "size": "4.99 GB", "start": "16384" } }, "removable": "0", "rotational": "1", "scheduler_mode": "noop", "sectors": "10485760", "sectorsize": "512", "size": "5.00 GB", "support_discard": "0", "vendor": "VMware" }, "sdc": { "holders": [], "host": "Serial Attached SCSI controller: VMware PVSCSI SCSI Controller (rev 02)", "model": "Virtual disk", "partitions": {}, "removable": "0", "rotational": "1", "scheduler_mode": "noop", "sectors": "14680064", "sectorsize": "512", "size": "7.00 GB", "support_discard": "0", "vendor": "VMware" } } }, "changed": false }

So there are 3 disks: sda, sdb and sdc. Two of them has partitions, one does not. So I want to loop over all disks and check which disk have partitions and which does not have and then do something about it. I know I can do something like this:

{{ ansible_devices['sda']['partitions'] }}

But when I will run this playbook I will not know neither disk labels nor number of disks.

Any ideas?

Thanks
Edgars

2

Hi Edgars,

You want to use ansible’s with_dict method of looping. Here is an example of looping through that dict and then a sample conditional for it as well
`

This is the sample with_dict loop

  • debug: msg=“The device {{ item.key }} with these partitions {{ item.value.partitions }}”
    with_dict: ansible_devices

This msg will only be printed on the condition that a device has no partitions

  • debug: msg=“The device {{ item.key }} has no partitions”
    with_dict: ansible_devices
    when: not item.value.partitions
    `

Hopefully that helps you out.

3

Great!! Thanks a lot!

Edgars

otrdiena, 2015. gada 24. marts 14:37:34 UTC+1, Jonathan Davila rakstīja:

4

Hey Guys,

I have the exact same issue where I need to find the drive that does not have any partitions on it.

so I have the exact same output from ansible_devices but I can’t figure out how I load the output into ansible so I can run the filter on it

basically i need an output like /dev/sdb or /dev/sdb or whatever the actual device name is that does not have partitions on it so I can then use that value in a subsequent - command: /usr/sbin//fdisk -l for example - command: /usr/sbin/fdisk -l /dev/sdb

any help will be much appreciated

Thanks

5

DS,

Try this.

This simple example will print the device name whenever the device has no partitions

`

  • name: Loop facts
    hosts: localhost
    connection: local
    tasks:
  • name: looping
    debug:
    msg: “{{ item.key }}”
    when: “not {{ item.value.partitions }}”
    with_dict: ansible_devices

`

6

Hey Jonathan,

Thanks for this.

I’ve figured it out using the previous examples and some more googleing :slight_smile:

I got it to execute a shell command which i what I needed it to do:

  • shell: pvcreate /dev/“{{ item.key }}”
    with_dict: ansible_devices
    when: not item.value.partitions and item.key != “sr0” and item.key != “fd0”

Thanks again