# Variable in a variable

**URL:** <https://forum.ansible.com/t/variable-in-a-variable/21734>\
**Category:** Ansible Project\
**Created:** [June 10, 2016, 2:47pm UTC](https://forum.ansible.com/t/variable-in-a-variable/21734 "2016-06-10T14:47:51Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Wawrzek\_Niewodniczan](https://avatars.discourse-cdn.com/v4/letter/w/bbe5ce/32.png) [@Wawrzek\_Niewodniczan](https://forum.ansible.com/u/Wawrzek_Niewodniczan)\
**Post date:** [June 10, 2016, 2:47pm UTC](https://forum.ansible.com/t/variable-in-a-variable/21734/1 "2016-06-10T14:47:51Z")

</div>

Hi,  
In a Jijna2 template I need a following variable from hostvars.

hostvars['{{project}}-example.com'].ansible\_eth0.ipv4.address

As you can see part of the hostname is dynamical created based  
external variable. I don't think such operation is possible. However,  
I wonder if there is any way to access such a variable.

Thanks,  
Wawrzek

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**Author:** ![Dick\_Davies](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Dick\_Davies](https://forum.ansible.com/u/Dick_Davies)\
**Post date:** [June 10, 2016, 3:21pm UTC](https://forum.ansible.com/t/variable-in-a-variable/21734/2 "2016-06-10T15:21:59Z")

</div>

Have you tried that? We used to use hostvars a lot\* and I'm sure I'd  
have done something like  
this previously.

\* (we got rid of them in the end because if 'project'-example.com was  
down, ansible couldn't run  
&nbsp;&nbsp;&nbsp;&nbsp;on any other boxes. In the end we to solve your sort of problem we  
just added DNS entries for  
&nbsp;&nbsp;&nbsp;&nbsp;those IPs and set vars explicitly in the plays)

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**Author:** ![Josh\_Smift1](https://avatars.discourse-cdn.com/v4/letter/j/bcef8e/32.png) [@Josh\_Smift1](https://forum.ansible.com/u/Josh_Smift1)\
**Post date:** [June 10, 2016, 3:35pm UTC](https://forum.ansible.com/t/variable-in-a-variable/21734/3 "2016-06-10T15:35:14Z")

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> In a Jijna2 template I need a following variable from hostvars.
> 
> hostvars['{{project}}-example.com'].ansible\_eth0.ipv4.address

I'm pretty sure something like

&nbsp;&nbsp;hostvars[project + '-example.com'].ansible\_eth0.ipv4.address

will work. You might need to bracket-ify the whole thing, like

&nbsp;&nbsp;hostvars[project + '-example.com']['ansible\_eth0']['ipv4']['address']

Not sure about that, I don't have a good sense of when Jinja lets you use  
dots to mean keys in a dict, and when it doesn't. And how it knows which  
are variables and which are literals. Anyway, something like that.

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;-Josh (jbs@care.com)

(apologies for the automatic corporate disclaimer that follows)

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<div class="post-metadata">

**Author:** ![Wawrzek\_Niewodniczan](https://avatars.discourse-cdn.com/v4/letter/w/bbe5ce/32.png) [@Wawrzek\_Niewodniczan](https://forum.ansible.com/u/Wawrzek_Niewodniczan)\
**Post date:** [June 10, 2016, 4:05pm UTC](https://forum.ansible.com/t/variable-in-a-variable/21734/4 "2016-06-10T16:05:06Z")

</div>

> \> In a Jijna2 template I need a following variable from hostvars.  
> \>  
> \> hostvars['{{project}}-example.com'].ansible\_eth0.ipv4.address

[...]

> will work. You might need to bracket-ify the whole thing, like
> 
> &nbsp;&nbsp;hostvars[project + '-example.com']['ansible\_eth0']['ipv4']['address']

Seems to work.

Thanks,  
Wawrzek