Looping through a group's IP numbers

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1

I have a rule like this:

  • name: Create user

mysql_user: name=app
host=={{ item }}
…
with_items:

  • localhost
  • 127.0.0.1
  • “{{ groups[‘webservers’] }}”

-

How can I make the list include IP numbers of each webserver host. I know I can use ansible_eth0.ipv4.address to map from hostname to IP, but I don’t know how to map a whole list to another list. And I can’t see any way to define a variable as the result of a loop.

2

I would split your create user into 2 tasks. 1 for localhost and the other for web servers:

  • name: Create localhost mysql users
    mysql_user: name=app host=“{{ item }}”
    with_items:

  • localhost

  • 127.0.0.1

  • name: Create webservers mysql users
    mysql_user: name=app host=“{{ hostvars[item][‘ansible_eth0’][‘ipv4’][‘address’] }}”
    with_items: groups[‘webservers’]

3

I see, thanks. I’d still be interested if there’s any other way to do it, as it would be useful elsewhere too and prefer not to duplicate plays if possible.

4

The other way to do it would be something like:

  • name: Create mysql servers
    mysql_user: name=app host=“{{ hostvars[item][‘ansible_eth0’][‘ipv4’][‘address’] if hostvars[item][‘ansible_eth0’] is defined else item }}”
    with_items:
  • localhost
  • 127.0.0.1
  • "{{ groups[‘webservers’] }}

The above example should work with 1.5, although I do believe that is over complicated, hard to read and not easily understand.

You could expand that to a regular {% if … %}{{ address }}{% else %}{{ item }}{% endif %} type line, but that gets even longer and harder to read in my opinion with all of the special characters that get mixed into that line.