# override non-defaults role variables **URL:** \ **Category:** Ansible Project\ **Created:** [January 22, 2015, 4:46pm UTC](https://forum.ansible.com/t/override-non-defaults-role-variables/17356 "2015-01-22T16:46:30Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Antoine\_Jacoutot](https://avatars.discourse-cdn.com/v4/letter/a/977dab/32.png) [@Antoine\_Jacoutot](https://forum.ansible.com/u/Antoine_Jacoutot)\ **Post date:** [January 22, 2015, 4:46pm UTC](https://forum.ansible.com/t/override-non-defaults-role-variables/17356/1 "2015-01-22T16:46:30Z")
Hi. After a lot of reading about variable inheritance in ansible, there’s still something I cannot properly grasp… I hope some folks in here could enlighten me 🙂 So. I have a “foobar” role with some default variables set under defaults/main.yml. So far, so good. But I would like some of these default variables to be for e.g. OS-dependant. I can easily achieve that using vars or with\_first\_found along with ansible\_os\_family. But if I do that, then I am not able to override these variables using group\_vars (/etc/ansible/group\_vars/mygroup (like I am able to override the variables set in defaults/main.yml). I do not want to have to pass variables directly in the inventory file. I am sure I am missing something stupid… Thanks in advance. ---
**Author:** ![James\_Martin1](https://avatars.discourse-cdn.com/v4/letter/j/0ea827/32.png) [@James\_Martin1](https://forum.ansible.com/u/James_Martin1)\ **Post date:** [January 22, 2015, 6:59pm UTC](https://forum.ansible.com/t/override-non-defaults-role-variables/17356/2 "2015-01-22T18:59:18Z")
Antoine, Let’s say for example you have your foobar role, and `#defaults/main.yml foobar_port: 42` And let’s say you have an inventory group called “foobar” which is a list of all your foobar hosts. By using the group\_by module ([http://docs.ansible.com/group\_by\_module.html](http://docs.ansible.com/group_by_module.html)) in a previous play, you can dynamic create a group based on the OS (or any other fact) ` Enter code here… - group\_by: key=machine\_{{ ansible\_distribution }} ` You would also have a `#group_vars/machine_Ubuntu foobar_port: 43` and a `#group_vars/machine_CentOS foobar_port: 44` That would render the 43 or 44, overriding the default role value and be dependent on the OS. - James ---
**Author:** ![Antoine\_Jacoutot](https://avatars.discourse-cdn.com/v4/letter/a/977dab/32.png) [@Antoine\_Jacoutot](https://forum.ansible.com/u/Antoine_Jacoutot)\ **Post date:** [January 23, 2015, 9:59am UTC](https://forum.ansible.com/t/override-non-defaults-role-variables/17356/3 "2015-01-23T09:59:39Z")
Hi James and thanks for the quick answer. I already tried what you proposed but my issue is that the role ended not being self-contained. i.e. I had to put the default os values under /etc/ansible/group\_vars/machine\_\* instead of within the role hierarchy. Or is there a way that I missed? Thanks. ---
**Author:** ![Tomasz\_Kontusz](https://avatars.discourse-cdn.com/v4/letter/t/bc79bd/32.png) [@Tomasz\_Kontusz](https://forum.ansible.com/u/Tomasz_Kontusz)\ **Post date:** [January 23, 2015, 10:42am UTC](https://forum.ansible.com/t/override-non-defaults-role-variables/17356/4 "2015-01-23T10:42:11Z")
There is another way: you can put "foo: ‘{{ default\_foo }}’ in defaults, and only set default\_foo in the per-OS variables Antoine Jacoutot [ajacoutot@bsdfrog.org](mailto:ajacoutot@bsdfrog.org) napisał: ---
**Author:** ![Antoine\_Jacoutot](https://avatars.discourse-cdn.com/v4/letter/a/977dab/32.png) [@Antoine\_Jacoutot](https://forum.ansible.com/u/Antoine_Jacoutot)\ **Post date:** [January 23, 2015, 1:13pm UTC](https://forum.ansible.com/t/override-non-defaults-role-variables/17356/5 "2015-01-23T13:13:45Z")
Ok, It took me a little while to understand what you meant with "only set default\_foo in the per-OS variables" but I think I got it. Thanks Tomasz, that's clever 🙂 For the record, this is what I ended up with and it seems to work fine (I can override one or more vars using the inventory hierarchy under /etc/ansible): (of course I have to duplicate all vars from defaults.yml into the OS-specific vars files, not just the ones that need overriding, but I can leave with that) # tasks/main.yml - name: OS-specific vars   include\_vars: "{{ item }}"   with\_first\_found:    - "defaults\_{{ ansible\_distribution }}.yml"    - "defaults\_{{ ansible\_os\_family }}.yml"    - "defaults.yml" # defaults/main.yml foobar: '{{ def\_foobar }}' # vars/defaults.yml def\_foobar: blahblah # vars/defaults\_CentOS.yml def\_foobar: blahblah-for-centos # var/defaults\_Debian.yml def\_foobar: blahblah-for-debian-family Thank you again Tomasz. Unless someone has a better idea...